1 /*
2 * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "aot/aotLoader.hpp"
27 #include "classfile/classFileParser.hpp"
28 #include "classfile/classFileStream.hpp"
29 #include "classfile/classLoader.hpp"
30 #include "classfile/javaClasses.hpp"
31 #include "classfile/moduleEntry.hpp"
32 #include "classfile/systemDictionary.hpp"
33 #include "classfile/systemDictionaryShared.hpp"
34 #include "classfile/verifier.hpp"
35 #include "classfile/vmSymbols.hpp"
36 #include "code/dependencyContext.hpp"
37 #include "compiler/compileBroker.hpp"
38 #include "gc/shared/collectedHeap.inline.hpp"
39 #include "gc/shared/specialized_oop_closures.hpp"
40 #include "interpreter/oopMapCache.hpp"
41 #include "interpreter/rewriter.hpp"
42 #include "jvmtifiles/jvmti.h"
43 #include "logging/log.hpp"
44 #include "logging/logMessage.hpp"
45 #include "logging/logStream.hpp"
46 #include "memory/heapInspection.hpp"
47 #include "memory/iterator.inline.hpp"
48 #include "memory/metadataFactory.hpp"
49 #include "memory/metaspaceClosure.hpp"
50 #include "memory/metaspaceShared.hpp"
51 #include "memory/oopFactory.hpp"
52 #include "memory/resourceArea.hpp"
53 #include "oops/fieldStreams.hpp"
54 #include "oops/instanceClassLoaderKlass.hpp"
55 #include "oops/instanceKlass.inline.hpp"
56 #include "oops/instanceMirrorKlass.hpp"
57 #include "oops/instanceOop.hpp"
58 #include "oops/klass.inline.hpp"
59 #include "oops/method.hpp"
60 #include "oops/oop.inline.hpp"
61 #include "oops/symbol.hpp"
62 #include "prims/jvm.h"
63 #include "prims/jvmtiExport.hpp"
64 #include "prims/jvmtiRedefineClasses.hpp"
65 #include "prims/jvmtiThreadState.hpp"
66 #include "prims/methodComparator.hpp"
67 #include "runtime/atomic.hpp"
68 #include "runtime/fieldDescriptor.hpp"
69 #include "runtime/handles.inline.hpp"
70 #include "runtime/javaCalls.hpp"
71 #include "runtime/mutexLocker.hpp"
72 #include "runtime/orderAccess.inline.hpp"
73 #include "runtime/thread.inline.hpp"
74 #include "services/classLoadingService.hpp"
75 #include "services/threadService.hpp"
76 #include "utilities/dtrace.hpp"
77 #include "utilities/macros.hpp"
78 #include "utilities/stringUtils.hpp"
79 #ifdef COMPILER1
80 #include "c1/c1_Compiler.hpp"
81 #endif
82
83 #ifdef DTRACE_ENABLED
84
85
86 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
87 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
88 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
89 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
90 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
91 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
92 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
93 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
94 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
95 { \
96 char* data = NULL; \
97 int len = 0; \
98 Symbol* clss_name = name(); \
99 if (clss_name != NULL) { \
100 data = (char*)clss_name->bytes(); \
101 len = clss_name->utf8_length(); \
102 } \
103 HOTSPOT_CLASS_INITIALIZATION_##type( \
104 data, len, (void*)class_loader(), thread_type); \
105 }
106
107 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
108 { \
109 char* data = NULL; \
110 int len = 0; \
111 Symbol* clss_name = name(); \
112 if (clss_name != NULL) { \
113 data = (char*)clss_name->bytes(); \
114 len = clss_name->utf8_length(); \
115 } \
116 HOTSPOT_CLASS_INITIALIZATION_##type( \
117 data, len, (void*)class_loader(), thread_type, wait); \
118 }
119
120 #else // ndef DTRACE_ENABLED
121
122 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
123 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
124
125 #endif // ndef DTRACE_ENABLED
126
127 volatile int InstanceKlass::_total_instanceKlass_count = 0;
128
129 static inline bool is_class_loader(const Symbol* class_name,
130 const ClassFileParser& parser) {
131 assert(class_name != NULL, "invariant");
132
133 if (class_name == vmSymbols::java_lang_ClassLoader()) {
134 return true;
135 }
136
137 if (SystemDictionary::ClassLoader_klass_loaded()) {
138 const Klass* const super_klass = parser.super_klass();
139 if (super_klass != NULL) {
140 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
141 return true;
142 }
143 }
144 }
145 return false;
146 }
147
148 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
149 const int size = InstanceKlass::size(parser.vtable_size(),
150 parser.itable_size(),
151 nonstatic_oop_map_size(parser.total_oop_map_count()),
152 parser.is_interface(),
153 parser.is_anonymous(),
154 should_store_fingerprint());
155
156 const Symbol* const class_name = parser.class_name();
157 assert(class_name != NULL, "invariant");
158 ClassLoaderData* loader_data = parser.loader_data();
159 assert(loader_data != NULL, "invariant");
160
161 InstanceKlass* ik;
162
163 // Allocation
164 if (REF_NONE == parser.reference_type()) {
165 if (class_name == vmSymbols::java_lang_Class()) {
166 // mirror
167 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
168 }
169 else if (is_class_loader(class_name, parser)) {
170 // class loader
171 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
172 }
173 else {
174 // normal
175 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
176 }
177 }
178 else {
179 // reference
180 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
181 }
182
183 // Check for pending exception before adding to the loader data and incrementing
184 // class count. Can get OOM here.
185 if (HAS_PENDING_EXCEPTION) {
186 return NULL;
187 }
188
189 assert(ik != NULL, "invariant");
190
191 const bool publicize = !parser.is_internal();
192
193 // Add all classes to our internal class loader list here,
194 // including classes in the bootstrap (NULL) class loader.
195 loader_data->add_class(ik, publicize);
196 Atomic::inc(&_total_instanceKlass_count);
197
198 return ik;
199 }
200
201
202 // copy method ordering from resource area to Metaspace
203 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
204 if (m != NULL) {
205 // allocate a new array and copy contents (memcpy?)
206 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
207 for (int i = 0; i < m->length(); i++) {
208 _method_ordering->at_put(i, m->at(i));
209 }
210 } else {
211 _method_ordering = Universe::the_empty_int_array();
212 }
213 }
214
215 // create a new array of vtable_indices for default methods
216 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
217 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
218 assert(default_vtable_indices() == NULL, "only create once");
219 set_default_vtable_indices(vtable_indices);
220 return vtable_indices;
221 }
222
223 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
224 _static_field_size(parser.static_field_size()),
225 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
226 _itable_len(parser.itable_size()),
227 _reference_type(parser.reference_type()) {
228 set_vtable_length(parser.vtable_size());
229 set_kind(kind);
230 set_access_flags(parser.access_flags());
231 set_is_anonymous(parser.is_anonymous());
232 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
233 false));
234
235 assert(NULL == _methods, "underlying memory not zeroed?");
236 assert(is_instance_klass(), "is layout incorrect?");
237 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
238 }
239
240 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
241 Array<Method*>* methods) {
242 if (methods != NULL && methods != Universe::the_empty_method_array() &&
243 !methods->is_shared()) {
244 for (int i = 0; i < methods->length(); i++) {
245 Method* method = methods->at(i);
246 if (method == NULL) continue; // maybe null if error processing
247 // Only want to delete methods that are not executing for RedefineClasses.
248 // The previous version will point to them so they're not totally dangling
249 assert (!method->on_stack(), "shouldn't be called with methods on stack");
250 MetadataFactory::free_metadata(loader_data, method);
251 }
252 MetadataFactory::free_array<Method*>(loader_data, methods);
253 }
254 }
255
256 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
257 const Klass* super_klass,
258 Array<Klass*>* local_interfaces,
259 Array<Klass*>* transitive_interfaces) {
260 // Only deallocate transitive interfaces if not empty, same as super class
261 // or same as local interfaces. See code in parseClassFile.
262 Array<Klass*>* ti = transitive_interfaces;
263 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
264 // check that the interfaces don't come from super class
265 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
266 InstanceKlass::cast(super_klass)->transitive_interfaces();
267 if (ti != sti && ti != NULL && !ti->is_shared()) {
268 MetadataFactory::free_array<Klass*>(loader_data, ti);
269 }
270 }
271
272 // local interfaces can be empty
273 if (local_interfaces != Universe::the_empty_klass_array() &&
274 local_interfaces != NULL && !local_interfaces->is_shared()) {
275 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
276 }
277 }
278
279 // This function deallocates the metadata and C heap pointers that the
280 // InstanceKlass points to.
281 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
282
283 // Orphan the mirror first, CMS thinks it's still live.
284 if (java_mirror() != NULL) {
285 java_lang_Class::set_klass(java_mirror(), NULL);
286 }
287
288 // Also remove mirror from handles
289 loader_data->remove_handle(_java_mirror);
290
291 // Need to take this class off the class loader data list.
292 loader_data->remove_class(this);
293
294 // The array_klass for this class is created later, after error handling.
295 // For class redefinition, we keep the original class so this scratch class
296 // doesn't have an array class. Either way, assert that there is nothing
297 // to deallocate.
298 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
299
300 // Release C heap allocated data that this might point to, which includes
301 // reference counting symbol names.
302 release_C_heap_structures();
303
304 deallocate_methods(loader_data, methods());
305 set_methods(NULL);
306
307 if (method_ordering() != NULL &&
308 method_ordering() != Universe::the_empty_int_array() &&
309 !method_ordering()->is_shared()) {
310 MetadataFactory::free_array<int>(loader_data, method_ordering());
311 }
312 set_method_ordering(NULL);
313
314 // default methods can be empty
315 if (default_methods() != NULL &&
316 default_methods() != Universe::the_empty_method_array() &&
317 !default_methods()->is_shared()) {
318 MetadataFactory::free_array<Method*>(loader_data, default_methods());
319 }
320 // Do NOT deallocate the default methods, they are owned by superinterfaces.
321 set_default_methods(NULL);
322
323 // default methods vtable indices can be empty
324 if (default_vtable_indices() != NULL &&
325 !default_vtable_indices()->is_shared()) {
326 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
327 }
328 set_default_vtable_indices(NULL);
329
330
331 // This array is in Klass, but remove it with the InstanceKlass since
332 // this place would be the only caller and it can share memory with transitive
333 // interfaces.
334 if (secondary_supers() != NULL &&
335 secondary_supers() != Universe::the_empty_klass_array() &&
336 secondary_supers() != transitive_interfaces() &&
337 !secondary_supers()->is_shared()) {
338 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
339 }
340 set_secondary_supers(NULL);
341
342 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
343 set_transitive_interfaces(NULL);
344 set_local_interfaces(NULL);
345
346 if (fields() != NULL && !fields()->is_shared()) {
347 MetadataFactory::free_array<jushort>(loader_data, fields());
348 }
349 set_fields(NULL, 0);
350
351 // If a method from a redefined class is using this constant pool, don't
352 // delete it, yet. The new class's previous version will point to this.
353 if (constants() != NULL) {
354 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
355 if (!constants()->is_shared()) {
356 MetadataFactory::free_metadata(loader_data, constants());
357 }
358 // Delete any cached resolution errors for the constant pool
359 SystemDictionary::delete_resolution_error(constants());
360
361 set_constants(NULL);
362 }
363
364 if (inner_classes() != NULL &&
365 inner_classes() != Universe::the_empty_short_array() &&
366 !inner_classes()->is_shared()) {
367 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
368 }
369 set_inner_classes(NULL);
370
371 // We should deallocate the Annotations instance if it's not in shared spaces.
372 if (annotations() != NULL && !annotations()->is_shared()) {
373 MetadataFactory::free_metadata(loader_data, annotations());
374 }
375 set_annotations(NULL);
376 }
377
378 bool InstanceKlass::should_be_initialized() const {
379 return !is_initialized();
380 }
381
382 klassItable InstanceKlass::itable() const {
383 return klassItable(const_cast<InstanceKlass*>(this));
384 }
385
386 void InstanceKlass::eager_initialize(Thread *thread) {
387 if (!EagerInitialization) return;
388
389 if (this->is_not_initialized()) {
390 // abort if the the class has a class initializer
391 if (this->class_initializer() != NULL) return;
392
393 // abort if it is java.lang.Object (initialization is handled in genesis)
394 Klass* super_klass = super();
395 if (super_klass == NULL) return;
396
397 // abort if the super class should be initialized
398 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
399
400 // call body to expose the this pointer
401 eager_initialize_impl();
402 }
403 }
404
405 // JVMTI spec thinks there are signers and protection domain in the
406 // instanceKlass. These accessors pretend these fields are there.
407 // The hprof specification also thinks these fields are in InstanceKlass.
408 oop InstanceKlass::protection_domain() const {
409 // return the protection_domain from the mirror
410 return java_lang_Class::protection_domain(java_mirror());
411 }
412
413 // To remove these from requires an incompatible change and CCC request.
414 objArrayOop InstanceKlass::signers() const {
415 // return the signers from the mirror
416 return java_lang_Class::signers(java_mirror());
417 }
418
419 oop InstanceKlass::init_lock() const {
420 // return the init lock from the mirror
421 oop lock = java_lang_Class::init_lock(java_mirror());
422 // Prevent reordering with any access of initialization state
423 OrderAccess::loadload();
424 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
425 "only fully initialized state can have a null lock");
426 return lock;
427 }
428
429 // Set the initialization lock to null so the object can be GC'ed. Any racing
430 // threads to get this lock will see a null lock and will not lock.
431 // That's okay because they all check for initialized state after getting
432 // the lock and return.
433 void InstanceKlass::fence_and_clear_init_lock() {
434 // make sure previous stores are all done, notably the init_state.
435 OrderAccess::storestore();
436 java_lang_Class::set_init_lock(java_mirror(), NULL);
437 assert(!is_not_initialized(), "class must be initialized now");
438 }
439
440 void InstanceKlass::eager_initialize_impl() {
441 EXCEPTION_MARK;
442 HandleMark hm(THREAD);
443 Handle h_init_lock(THREAD, init_lock());
444 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
445
446 // abort if someone beat us to the initialization
447 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
448
449 ClassState old_state = init_state();
450 link_class_impl(true, THREAD);
451 if (HAS_PENDING_EXCEPTION) {
452 CLEAR_PENDING_EXCEPTION;
453 // Abort if linking the class throws an exception.
454
455 // Use a test to avoid redundantly resetting the state if there's
456 // no change. Set_init_state() asserts that state changes make
457 // progress, whereas here we might just be spinning in place.
458 if (old_state != _init_state)
459 set_init_state(old_state);
460 } else {
461 // linking successfull, mark class as initialized
462 set_init_state(fully_initialized);
463 fence_and_clear_init_lock();
464 // trace
465 if (log_is_enabled(Info, class, init)) {
466 ResourceMark rm(THREAD);
467 log_info(class, init)("[Initialized %s without side effects]", external_name());
468 }
469 }
470 }
471
472
473 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
474 // process. The step comments refers to the procedure described in that section.
475 // Note: implementation moved to static method to expose the this pointer.
476 void InstanceKlass::initialize(TRAPS) {
477 if (this->should_be_initialized()) {
478 initialize_impl(CHECK);
479 // Note: at this point the class may be initialized
480 // OR it may be in the state of being initialized
481 // in case of recursive initialization!
482 } else {
483 assert(is_initialized(), "sanity check");
484 }
485 }
486
487
488 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) {
489 // 1) Verify the bytecodes
490 Verifier::Mode mode =
491 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
492 return Verifier::verify(this, mode, should_verify_class(), THREAD);
493 }
494
495
496 // Used exclusively by the shared spaces dump mechanism to prevent
497 // classes mapped into the shared regions in new VMs from appearing linked.
498
499 void InstanceKlass::unlink_class() {
500 assert(is_linked(), "must be linked");
501 _init_state = loaded;
502 }
503
504 void InstanceKlass::link_class(TRAPS) {
505 assert(is_loaded(), "must be loaded");
506 if (!is_linked()) {
507 link_class_impl(true, CHECK);
508 }
509 }
510
511 // Called to verify that a class can link during initialization, without
512 // throwing a VerifyError.
513 bool InstanceKlass::link_class_or_fail(TRAPS) {
514 assert(is_loaded(), "must be loaded");
515 if (!is_linked()) {
516 link_class_impl(false, CHECK_false);
517 }
518 return is_linked();
519 }
520
521 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) {
522 if (DumpSharedSpaces && is_in_error_state()) {
523 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
524 // the class has failed verification. Throwing the NoClassDefFoundError here is just
525 // a convenient way to stop repeat attempts to verify the same (bad) class.
526 //
527 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
528 // if we are executing Java code. This is not a problem for CDS dumping phase since
529 // it doesn't execute any Java code.
530 ResourceMark rm(THREAD);
531 Exceptions::fthrow(THREAD_AND_LOCATION,
532 vmSymbols::java_lang_NoClassDefFoundError(),
533 "Class %s, or one of its supertypes, failed class initialization",
534 external_name());
535 return false;
536 }
537 // return if already verified
538 if (is_linked()) {
539 return true;
540 }
541
542 // Timing
543 // timer handles recursion
544 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
545 JavaThread* jt = (JavaThread*)THREAD;
546
547 // link super class before linking this class
548 Klass* super_klass = super();
549 if (super_klass != NULL) {
550 if (super_klass->is_interface()) { // check if super class is an interface
551 ResourceMark rm(THREAD);
552 Exceptions::fthrow(
553 THREAD_AND_LOCATION,
554 vmSymbols::java_lang_IncompatibleClassChangeError(),
555 "class %s has interface %s as super class",
556 external_name(),
557 super_klass->external_name()
558 );
559 return false;
560 }
561
562 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
563 ik_super->link_class_impl(throw_verifyerror, CHECK_false);
564 }
565
566 // link all interfaces implemented by this class before linking this class
567 Array<Klass*>* interfaces = local_interfaces();
568 int num_interfaces = interfaces->length();
569 for (int index = 0; index < num_interfaces; index++) {
570 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index));
571 interk->link_class_impl(throw_verifyerror, CHECK_false);
572 }
573
574 // in case the class is linked in the process of linking its superclasses
575 if (is_linked()) {
576 return true;
577 }
578
579 // trace only the link time for this klass that includes
580 // the verification time
581 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
582 ClassLoader::perf_class_link_selftime(),
583 ClassLoader::perf_classes_linked(),
584 jt->get_thread_stat()->perf_recursion_counts_addr(),
585 jt->get_thread_stat()->perf_timers_addr(),
586 PerfClassTraceTime::CLASS_LINK);
587
588 // verification & rewriting
589 {
590 HandleMark hm(THREAD);
591 Handle h_init_lock(THREAD, init_lock());
592 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
593 // rewritten will have been set if loader constraint error found
594 // on an earlier link attempt
595 // don't verify or rewrite if already rewritten
596 //
597
598 if (!is_linked()) {
599 if (!is_rewritten()) {
600 {
601 bool verify_ok = verify_code(throw_verifyerror, THREAD);
602 if (!verify_ok) {
603 return false;
604 }
605 }
606
607 // Just in case a side-effect of verify linked this class already
608 // (which can sometimes happen since the verifier loads classes
609 // using custom class loaders, which are free to initialize things)
610 if (is_linked()) {
611 return true;
612 }
613
614 // also sets rewritten
615 rewrite_class(CHECK_false);
616 } else if (is_shared()) {
617 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
618 }
619
620 // relocate jsrs and link methods after they are all rewritten
621 link_methods(CHECK_false);
622
623 // Initialize the vtable and interface table after
624 // methods have been rewritten since rewrite may
625 // fabricate new Method*s.
626 // also does loader constraint checking
627 //
628 // initialize_vtable and initialize_itable need to be rerun for
629 // a shared class if the class is not loaded by the NULL classloader.
630 ClassLoaderData * loader_data = class_loader_data();
631 if (!(is_shared() &&
632 loader_data->is_the_null_class_loader_data())) {
633 ResourceMark rm(THREAD);
634 vtable().initialize_vtable(true, CHECK_false);
635 itable().initialize_itable(true, CHECK_false);
636 }
637 #ifdef ASSERT
638 else {
639 vtable().verify(tty, true);
640 // In case itable verification is ever added.
641 // itable().verify(tty, true);
642 }
643 #endif
644 set_init_state(linked);
645 if (JvmtiExport::should_post_class_prepare()) {
646 Thread *thread = THREAD;
647 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
648 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
649 }
650 }
651 }
652 return true;
653 }
654
655
656 // Rewrite the byte codes of all of the methods of a class.
657 // The rewriter must be called exactly once. Rewriting must happen after
658 // verification but before the first method of the class is executed.
659 void InstanceKlass::rewrite_class(TRAPS) {
660 assert(is_loaded(), "must be loaded");
661 if (is_rewritten()) {
662 assert(is_shared(), "rewriting an unshared class?");
663 return;
664 }
665 Rewriter::rewrite(this, CHECK);
666 set_rewritten();
667 }
668
669 // Now relocate and link method entry points after class is rewritten.
670 // This is outside is_rewritten flag. In case of an exception, it can be
671 // executed more than once.
672 void InstanceKlass::link_methods(TRAPS) {
673 int len = methods()->length();
674 for (int i = len-1; i >= 0; i--) {
675 methodHandle m(THREAD, methods()->at(i));
676
677 // Set up method entry points for compiler and interpreter .
678 m->link_method(m, CHECK);
679 }
680 }
681
682 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
683 void InstanceKlass::initialize_super_interfaces(TRAPS) {
684 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
685 for (int i = 0; i < local_interfaces()->length(); ++i) {
686 Klass* iface = local_interfaces()->at(i);
687 InstanceKlass* ik = InstanceKlass::cast(iface);
688
689 // Initialization is depth first search ie. we start with top of the inheritance tree
690 // has_nonstatic_concrete_methods drives searching superinterfaces since it
691 // means has_nonstatic_concrete_methods in its superinterface hierarchy
692 if (ik->has_nonstatic_concrete_methods()) {
693 ik->initialize_super_interfaces(CHECK);
694 }
695
696 // Only initialize() interfaces that "declare" concrete methods.
697 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
698 ik->initialize(CHECK);
699 }
700 }
701 }
702
703 void InstanceKlass::initialize_impl(TRAPS) {
704 HandleMark hm(THREAD);
705
706 // Make sure klass is linked (verified) before initialization
707 // A class could already be verified, since it has been reflected upon.
708 link_class(CHECK);
709
710 DTRACE_CLASSINIT_PROBE(required, -1);
711
712 bool wait = false;
713
714 // refer to the JVM book page 47 for description of steps
715 // Step 1
716 {
717 Handle h_init_lock(THREAD, init_lock());
718 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
719
720 Thread *self = THREAD; // it's passed the current thread
721
722 // Step 2
723 // If we were to use wait() instead of waitInterruptibly() then
724 // we might end up throwing IE from link/symbol resolution sites
725 // that aren't expected to throw. This would wreak havoc. See 6320309.
726 while(is_being_initialized() && !is_reentrant_initialization(self)) {
727 wait = true;
728 ol.waitUninterruptibly(CHECK);
729 }
730
731 // Step 3
732 if (is_being_initialized() && is_reentrant_initialization(self)) {
733 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
734 return;
735 }
736
737 // Step 4
738 if (is_initialized()) {
739 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
740 return;
741 }
742
743 // Step 5
744 if (is_in_error_state()) {
745 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
746 ResourceMark rm(THREAD);
747 const char* desc = "Could not initialize class ";
748 const char* className = external_name();
749 size_t msglen = strlen(desc) + strlen(className) + 1;
750 char* message = NEW_RESOURCE_ARRAY(char, msglen);
751 if (NULL == message) {
752 // Out of memory: can't create detailed error message
753 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
754 } else {
755 jio_snprintf(message, msglen, "%s%s", desc, className);
756 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
757 }
758 }
759
760 // Step 6
761 set_init_state(being_initialized);
762 set_init_thread(self);
763 }
764
765 // Step 7
766 // Next, if C is a class rather than an interface, initialize it's super class and super
767 // interfaces.
768 if (!is_interface()) {
769 Klass* super_klass = super();
770 if (super_klass != NULL && super_klass->should_be_initialized()) {
771 super_klass->initialize(THREAD);
772 }
773 // If C implements any interface that declares a non-static, concrete method,
774 // the initialization of C triggers initialization of its super interfaces.
775 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
776 // having a superinterface that declares, non-static, concrete methods
777 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
778 initialize_super_interfaces(THREAD);
779 }
780
781 // If any exceptions, complete abruptly, throwing the same exception as above.
782 if (HAS_PENDING_EXCEPTION) {
783 Handle e(THREAD, PENDING_EXCEPTION);
784 CLEAR_PENDING_EXCEPTION;
785 {
786 EXCEPTION_MARK;
787 // Locks object, set state, and notify all waiting threads
788 set_initialization_state_and_notify(initialization_error, THREAD);
789 CLEAR_PENDING_EXCEPTION;
790 }
791 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
792 THROW_OOP(e());
793 }
794 }
795
796
797 // Look for aot compiled methods for this klass, including class initializer.
798 AOTLoader::load_for_klass(this, THREAD);
799
800 // Step 8
801 {
802 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
803 JavaThread* jt = (JavaThread*)THREAD;
804 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
805 // Timer includes any side effects of class initialization (resolution,
806 // etc), but not recursive entry into call_class_initializer().
807 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
808 ClassLoader::perf_class_init_selftime(),
809 ClassLoader::perf_classes_inited(),
810 jt->get_thread_stat()->perf_recursion_counts_addr(),
811 jt->get_thread_stat()->perf_timers_addr(),
812 PerfClassTraceTime::CLASS_CLINIT);
813 call_class_initializer(THREAD);
814 }
815
816 // Step 9
817 if (!HAS_PENDING_EXCEPTION) {
818 set_initialization_state_and_notify(fully_initialized, CHECK);
819 {
820 debug_only(vtable().verify(tty, true);)
821 }
822 }
823 else {
824 // Step 10 and 11
825 Handle e(THREAD, PENDING_EXCEPTION);
826 CLEAR_PENDING_EXCEPTION;
827 // JVMTI has already reported the pending exception
828 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
829 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
830 {
831 EXCEPTION_MARK;
832 set_initialization_state_and_notify(initialization_error, THREAD);
833 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
834 // JVMTI has already reported the pending exception
835 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
836 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
837 }
838 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
839 if (e->is_a(SystemDictionary::Error_klass())) {
840 THROW_OOP(e());
841 } else {
842 JavaCallArguments args(e);
843 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
844 vmSymbols::throwable_void_signature(),
845 &args);
846 }
847 }
848 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
849 }
850
851
852 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
853 Handle h_init_lock(THREAD, init_lock());
854 if (h_init_lock() != NULL) {
855 ObjectLocker ol(h_init_lock, THREAD);
856 set_init_state(state);
857 fence_and_clear_init_lock();
858 ol.notify_all(CHECK);
859 } else {
860 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
861 set_init_state(state);
862 }
863 }
864
865 // The embedded _implementor field can only record one implementor.
866 // When there are more than one implementors, the _implementor field
867 // is set to the interface Klass* itself. Following are the possible
868 // values for the _implementor field:
869 // NULL - no implementor
870 // implementor Klass* - one implementor
871 // self - more than one implementor
872 //
873 // The _implementor field only exists for interfaces.
874 void InstanceKlass::add_implementor(Klass* k) {
875 assert(Compile_lock->owned_by_self(), "");
876 assert(is_interface(), "not interface");
877 // Filter out my subinterfaces.
878 // (Note: Interfaces are never on the subklass list.)
879 if (InstanceKlass::cast(k)->is_interface()) return;
880
881 // Filter out subclasses whose supers already implement me.
882 // (Note: CHA must walk subclasses of direct implementors
883 // in order to locate indirect implementors.)
884 Klass* sk = k->super();
885 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
886 // We only need to check one immediate superclass, since the
887 // implements_interface query looks at transitive_interfaces.
888 // Any supers of the super have the same (or fewer) transitive_interfaces.
889 return;
890
891 Klass* ik = implementor();
892 if (ik == NULL) {
893 set_implementor(k);
894 } else if (ik != this) {
895 // There is already an implementor. Use itself as an indicator of
896 // more than one implementors.
897 set_implementor(this);
898 }
899
900 // The implementor also implements the transitive_interfaces
901 for (int index = 0; index < local_interfaces()->length(); index++) {
902 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
903 }
904 }
905
906 void InstanceKlass::init_implementor() {
907 if (is_interface()) {
908 set_implementor(NULL);
909 }
910 }
911
912
913 void InstanceKlass::process_interfaces(Thread *thread) {
914 // link this class into the implementors list of every interface it implements
915 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
916 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
917 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
918 assert(interf->is_interface(), "expected interface");
919 interf->add_implementor(this);
920 }
921 }
922
923 bool InstanceKlass::can_be_primary_super_slow() const {
924 if (is_interface())
925 return false;
926 else
927 return Klass::can_be_primary_super_slow();
928 }
929
930 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
931 // The secondaries are the implemented interfaces.
932 Array<Klass*>* interfaces = transitive_interfaces();
933 int num_secondaries = num_extra_slots + interfaces->length();
934 if (num_secondaries == 0) {
935 // Must share this for correct bootstrapping!
936 set_secondary_supers(Universe::the_empty_klass_array());
937 return NULL;
938 } else if (num_extra_slots == 0) {
939 // The secondary super list is exactly the same as the transitive interfaces.
940 // Redefine classes has to be careful not to delete this!
941 set_secondary_supers(interfaces);
942 return NULL;
943 } else {
944 // Copy transitive interfaces to a temporary growable array to be constructed
945 // into the secondary super list with extra slots.
946 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
947 for (int i = 0; i < interfaces->length(); i++) {
948 secondaries->push(interfaces->at(i));
949 }
950 return secondaries;
951 }
952 }
953
954 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
955 if (k->is_interface()) {
956 return implements_interface(k);
957 } else {
958 return Klass::compute_is_subtype_of(k);
959 }
960 }
961
962 bool InstanceKlass::implements_interface(Klass* k) const {
963 if (this == k) return true;
964 assert(k->is_interface(), "should be an interface class");
965 for (int i = 0; i < transitive_interfaces()->length(); i++) {
966 if (transitive_interfaces()->at(i) == k) {
967 return true;
968 }
969 }
970 return false;
971 }
972
973 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
974 // Verify direct super interface
975 if (this == k) return true;
976 assert(k->is_interface(), "should be an interface class");
977 for (int i = 0; i < local_interfaces()->length(); i++) {
978 if (local_interfaces()->at(i) == k) {
979 return true;
980 }
981 }
982 return false;
983 }
984
985 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
986 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
987 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
988 report_java_out_of_memory("Requested array size exceeds VM limit");
989 JvmtiExport::post_array_size_exhausted();
990 THROW_OOP_0(Universe::out_of_memory_error_array_size());
991 }
992 int size = objArrayOopDesc::object_size(length);
993 Klass* ak = array_klass(n, CHECK_NULL);
994 objArrayOop o =
995 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL);
996 return o;
997 }
998
999 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1000 if (TraceFinalizerRegistration) {
1001 tty->print("Registered ");
1002 i->print_value_on(tty);
1003 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1004 }
1005 instanceHandle h_i(THREAD, i);
1006 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1007 JavaValue result(T_VOID);
1008 JavaCallArguments args(h_i);
1009 methodHandle mh (THREAD, Universe::finalizer_register_method());
1010 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1011 return h_i();
1012 }
1013
1014 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1015 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1016 int size = size_helper(); // Query before forming handle.
1017
1018 instanceOop i;
1019
1020 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL);
1021 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1022 i = register_finalizer(i, CHECK_NULL);
1023 }
1024 return i;
1025 }
1026
1027 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1028 if (is_interface() || is_abstract()) {
1029 ResourceMark rm(THREAD);
1030 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1031 : vmSymbols::java_lang_InstantiationException(), external_name());
1032 }
1033 if (this == SystemDictionary::Class_klass()) {
1034 ResourceMark rm(THREAD);
1035 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1036 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1037 }
1038 }
1039
1040 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1041 // Need load-acquire for lock-free read
1042 if (array_klasses_acquire() == NULL) {
1043 if (or_null) return NULL;
1044
1045 ResourceMark rm;
1046 JavaThread *jt = (JavaThread *)THREAD;
1047 {
1048 // Atomic creation of array_klasses
1049 MutexLocker mc(Compile_lock, THREAD); // for vtables
1050 MutexLocker ma(MultiArray_lock, THREAD);
1051
1052 // Check if update has already taken place
1053 if (array_klasses() == NULL) {
1054 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1055 // use 'release' to pair with lock-free load
1056 release_set_array_klasses(k);
1057 }
1058 }
1059 }
1060 // _this will always be set at this point
1061 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1062 if (or_null) {
1063 return oak->array_klass_or_null(n);
1064 }
1065 return oak->array_klass(n, THREAD);
1066 }
1067
1068 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1069 return array_klass_impl(or_null, 1, THREAD);
1070 }
1071
1072 static int call_class_initializer_counter = 0; // for debugging
1073
1074 Method* InstanceKlass::class_initializer() const {
1075 Method* clinit = find_method(
1076 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1077 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1078 return clinit;
1079 }
1080 return NULL;
1081 }
1082
1083 void InstanceKlass::call_class_initializer(TRAPS) {
1084 if (ReplayCompiles &&
1085 (ReplaySuppressInitializers == 1 ||
1086 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1087 // Hide the existence of the initializer for the purpose of replaying the compile
1088 return;
1089 }
1090
1091 methodHandle h_method(THREAD, class_initializer());
1092 assert(!is_initialized(), "we cannot initialize twice");
1093 LogTarget(Info, class, init) lt;
1094 if (lt.is_enabled()) {
1095 ResourceMark rm;
1096 LogStream ls(lt);
1097 ls.print("%d Initializing ", call_class_initializer_counter++);
1098 name()->print_value_on(&ls);
1099 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1100 }
1101 if (h_method() != NULL) {
1102 JavaCallArguments args; // No arguments
1103 JavaValue result(T_VOID);
1104 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1105 }
1106 }
1107
1108
1109 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1110 InterpreterOopMap* entry_for) {
1111 // Lazily create the _oop_map_cache at first request
1112 // Lock-free access requires load_acquire.
1113 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1114 if (oop_map_cache == NULL) {
1115 MutexLocker x(OopMapCacheAlloc_lock);
1116 // Check if _oop_map_cache was allocated while we were waiting for this lock
1117 if ((oop_map_cache = _oop_map_cache) == NULL) {
1118 oop_map_cache = new OopMapCache();
1119 // Ensure _oop_map_cache is stable, since it is examined without a lock
1120 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1121 }
1122 }
1123 // _oop_map_cache is constant after init; lookup below does its own locking.
1124 oop_map_cache->lookup(method, bci, entry_for);
1125 }
1126
1127
1128 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1129 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1130 Symbol* f_name = fs.name();
1131 Symbol* f_sig = fs.signature();
1132 if (f_name == name && f_sig == sig) {
1133 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1134 return true;
1135 }
1136 }
1137 return false;
1138 }
1139
1140
1141 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1142 const int n = local_interfaces()->length();
1143 for (int i = 0; i < n; i++) {
1144 Klass* intf1 = local_interfaces()->at(i);
1145 assert(intf1->is_interface(), "just checking type");
1146 // search for field in current interface
1147 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1148 assert(fd->is_static(), "interface field must be static");
1149 return intf1;
1150 }
1151 // search for field in direct superinterfaces
1152 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1153 if (intf2 != NULL) return intf2;
1154 }
1155 // otherwise field lookup fails
1156 return NULL;
1157 }
1158
1159
1160 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1161 // search order according to newest JVM spec (5.4.3.2, p.167).
1162 // 1) search for field in current klass
1163 if (find_local_field(name, sig, fd)) {
1164 return const_cast<InstanceKlass*>(this);
1165 }
1166 // 2) search for field recursively in direct superinterfaces
1167 { Klass* intf = find_interface_field(name, sig, fd);
1168 if (intf != NULL) return intf;
1169 }
1170 // 3) apply field lookup recursively if superclass exists
1171 { Klass* supr = super();
1172 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1173 }
1174 // 4) otherwise field lookup fails
1175 return NULL;
1176 }
1177
1178
1179 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1180 // search order according to newest JVM spec (5.4.3.2, p.167).
1181 // 1) search for field in current klass
1182 if (find_local_field(name, sig, fd)) {
1183 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1184 }
1185 // 2) search for field recursively in direct superinterfaces
1186 if (is_static) {
1187 Klass* intf = find_interface_field(name, sig, fd);
1188 if (intf != NULL) return intf;
1189 }
1190 // 3) apply field lookup recursively if superclass exists
1191 { Klass* supr = super();
1192 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1193 }
1194 // 4) otherwise field lookup fails
1195 return NULL;
1196 }
1197
1198
1199 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1200 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1201 if (fs.offset() == offset) {
1202 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1203 if (fd->is_static() == is_static) return true;
1204 }
1205 }
1206 return false;
1207 }
1208
1209
1210 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1211 Klass* klass = const_cast<InstanceKlass*>(this);
1212 while (klass != NULL) {
1213 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1214 return true;
1215 }
1216 klass = klass->super();
1217 }
1218 return false;
1219 }
1220
1221
1222 void InstanceKlass::methods_do(void f(Method* method)) {
1223 // Methods aren't stable until they are loaded. This can be read outside
1224 // a lock through the ClassLoaderData for profiling
1225 if (!is_loaded()) {
1226 return;
1227 }
1228
1229 int len = methods()->length();
1230 for (int index = 0; index < len; index++) {
1231 Method* m = methods()->at(index);
1232 assert(m->is_method(), "must be method");
1233 f(m);
1234 }
1235 }
1236
1237
1238 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1239 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1240 if (fs.access_flags().is_static()) {
1241 fieldDescriptor& fd = fs.field_descriptor();
1242 cl->do_field(&fd);
1243 }
1244 }
1245 }
1246
1247
1248 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1249 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1250 if (fs.access_flags().is_static()) {
1251 fieldDescriptor& fd = fs.field_descriptor();
1252 f(&fd, mirror, CHECK);
1253 }
1254 }
1255 }
1256
1257
1258 static int compare_fields_by_offset(int* a, int* b) {
1259 return a[0] - b[0];
1260 }
1261
1262 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1263 InstanceKlass* super = superklass();
1264 if (super != NULL) {
1265 super->do_nonstatic_fields(cl);
1266 }
1267 fieldDescriptor fd;
1268 int length = java_fields_count();
1269 // In DebugInfo nonstatic fields are sorted by offset.
1270 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1271 int j = 0;
1272 for (int i = 0; i < length; i += 1) {
1273 fd.reinitialize(this, i);
1274 if (!fd.is_static()) {
1275 fields_sorted[j + 0] = fd.offset();
1276 fields_sorted[j + 1] = i;
1277 j += 2;
1278 }
1279 }
1280 if (j > 0) {
1281 length = j;
1282 // _sort_Fn is defined in growableArray.hpp.
1283 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1284 for (int i = 0; i < length; i += 2) {
1285 fd.reinitialize(this, fields_sorted[i + 1]);
1286 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1287 cl->do_field(&fd);
1288 }
1289 }
1290 FREE_C_HEAP_ARRAY(int, fields_sorted);
1291 }
1292
1293
1294 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1295 if (array_klasses() != NULL)
1296 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1297 }
1298
1299 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1300 if (array_klasses() != NULL)
1301 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1302 }
1303
1304 #ifdef ASSERT
1305 static int linear_search(const Array<Method*>* methods,
1306 const Symbol* name,
1307 const Symbol* signature) {
1308 const int len = methods->length();
1309 for (int index = 0; index < len; index++) {
1310 const Method* const m = methods->at(index);
1311 assert(m->is_method(), "must be method");
1312 if (m->signature() == signature && m->name() == name) {
1313 return index;
1314 }
1315 }
1316 return -1;
1317 }
1318 #endif
1319
1320 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1321 int len = methods->length();
1322 // methods are sorted, so do binary search
1323 int l = 0;
1324 int h = len - 1;
1325 while (l <= h) {
1326 int mid = (l + h) >> 1;
1327 Method* m = methods->at(mid);
1328 assert(m->is_method(), "must be method");
1329 int res = m->name()->fast_compare(name);
1330 if (res == 0) {
1331 return mid;
1332 } else if (res < 0) {
1333 l = mid + 1;
1334 } else {
1335 h = mid - 1;
1336 }
1337 }
1338 return -1;
1339 }
1340
1341 // find_method looks up the name/signature in the local methods array
1342 Method* InstanceKlass::find_method(const Symbol* name,
1343 const Symbol* signature) const {
1344 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1345 }
1346
1347 Method* InstanceKlass::find_method_impl(const Symbol* name,
1348 const Symbol* signature,
1349 OverpassLookupMode overpass_mode,
1350 StaticLookupMode static_mode,
1351 PrivateLookupMode private_mode) const {
1352 return InstanceKlass::find_method_impl(methods(),
1353 name,
1354 signature,
1355 overpass_mode,
1356 static_mode,
1357 private_mode);
1358 }
1359
1360 // find_instance_method looks up the name/signature in the local methods array
1361 // and skips over static methods
1362 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1363 const Symbol* name,
1364 const Symbol* signature) {
1365 Method* const meth = InstanceKlass::find_method_impl(methods,
1366 name,
1367 signature,
1368 find_overpass,
1369 skip_static,
1370 find_private);
1371 assert(((meth == NULL) || !meth->is_static()),
1372 "find_instance_method should have skipped statics");
1373 return meth;
1374 }
1375
1376 // find_instance_method looks up the name/signature in the local methods array
1377 // and skips over static methods
1378 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1379 return InstanceKlass::find_instance_method(methods(), name, signature);
1380 }
1381
1382 // Find looks up the name/signature in the local methods array
1383 // and filters on the overpass, static and private flags
1384 // This returns the first one found
1385 // note that the local methods array can have up to one overpass, one static
1386 // and one instance (private or not) with the same name/signature
1387 Method* InstanceKlass::find_local_method(const Symbol* name,
1388 const Symbol* signature,
1389 OverpassLookupMode overpass_mode,
1390 StaticLookupMode static_mode,
1391 PrivateLookupMode private_mode) const {
1392 return InstanceKlass::find_method_impl(methods(),
1393 name,
1394 signature,
1395 overpass_mode,
1396 static_mode,
1397 private_mode);
1398 }
1399
1400 // Find looks up the name/signature in the local methods array
1401 // and filters on the overpass, static and private flags
1402 // This returns the first one found
1403 // note that the local methods array can have up to one overpass, one static
1404 // and one instance (private or not) with the same name/signature
1405 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1406 const Symbol* name,
1407 const Symbol* signature,
1408 OverpassLookupMode overpass_mode,
1409 StaticLookupMode static_mode,
1410 PrivateLookupMode private_mode) {
1411 return InstanceKlass::find_method_impl(methods,
1412 name,
1413 signature,
1414 overpass_mode,
1415 static_mode,
1416 private_mode);
1417 }
1418
1419 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1420 const Symbol* name,
1421 const Symbol* signature) {
1422 return InstanceKlass::find_method_impl(methods,
1423 name,
1424 signature,
1425 find_overpass,
1426 find_static,
1427 find_private);
1428 }
1429
1430 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1431 const Symbol* name,
1432 const Symbol* signature,
1433 OverpassLookupMode overpass_mode,
1434 StaticLookupMode static_mode,
1435 PrivateLookupMode private_mode) {
1436 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1437 return hit >= 0 ? methods->at(hit): NULL;
1438 }
1439
1440 // true if method matches signature and conforms to skipping_X conditions.
1441 static bool method_matches(const Method* m,
1442 const Symbol* signature,
1443 bool skipping_overpass,
1444 bool skipping_static,
1445 bool skipping_private) {
1446 return ((m->signature() == signature) &&
1447 (!skipping_overpass || !m->is_overpass()) &&
1448 (!skipping_static || !m->is_static()) &&
1449 (!skipping_private || !m->is_private()));
1450 }
1451
1452 // Used directly for default_methods to find the index into the
1453 // default_vtable_indices, and indirectly by find_method
1454 // find_method_index looks in the local methods array to return the index
1455 // of the matching name/signature. If, overpass methods are being ignored,
1456 // the search continues to find a potential non-overpass match. This capability
1457 // is important during method resolution to prefer a static method, for example,
1458 // over an overpass method.
1459 // There is the possibility in any _method's array to have the same name/signature
1460 // for a static method, an overpass method and a local instance method
1461 // To correctly catch a given method, the search criteria may need
1462 // to explicitly skip the other two. For local instance methods, it
1463 // is often necessary to skip private methods
1464 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1465 const Symbol* name,
1466 const Symbol* signature,
1467 OverpassLookupMode overpass_mode,
1468 StaticLookupMode static_mode,
1469 PrivateLookupMode private_mode) {
1470 const bool skipping_overpass = (overpass_mode == skip_overpass);
1471 const bool skipping_static = (static_mode == skip_static);
1472 const bool skipping_private = (private_mode == skip_private);
1473 const int hit = binary_search(methods, name);
1474 if (hit != -1) {
1475 const Method* const m = methods->at(hit);
1476
1477 // Do linear search to find matching signature. First, quick check
1478 // for common case, ignoring overpasses if requested.
1479 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1480 return hit;
1481 }
1482
1483 // search downwards through overloaded methods
1484 int i;
1485 for (i = hit - 1; i >= 0; --i) {
1486 const Method* const m = methods->at(i);
1487 assert(m->is_method(), "must be method");
1488 if (m->name() != name) {
1489 break;
1490 }
1491 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1492 return i;
1493 }
1494 }
1495 // search upwards
1496 for (i = hit + 1; i < methods->length(); ++i) {
1497 const Method* const m = methods->at(i);
1498 assert(m->is_method(), "must be method");
1499 if (m->name() != name) {
1500 break;
1501 }
1502 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1503 return i;
1504 }
1505 }
1506 // not found
1507 #ifdef ASSERT
1508 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1509 linear_search(methods, name, signature);
1510 assert(-1 == index, "binary search should have found entry %d", index);
1511 #endif
1512 }
1513 return -1;
1514 }
1515
1516 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1517 return find_method_by_name(methods(), name, end);
1518 }
1519
1520 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1521 const Symbol* name,
1522 int* end_ptr) {
1523 assert(end_ptr != NULL, "just checking");
1524 int start = binary_search(methods, name);
1525 int end = start + 1;
1526 if (start != -1) {
1527 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1528 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1529 *end_ptr = end;
1530 return start;
1531 }
1532 return -1;
1533 }
1534
1535 // uncached_lookup_method searches both the local class methods array and all
1536 // superclasses methods arrays, skipping any overpass methods in superclasses.
1537 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1538 const Symbol* signature,
1539 OverpassLookupMode overpass_mode) const {
1540 OverpassLookupMode overpass_local_mode = overpass_mode;
1541 const Klass* klass = this;
1542 while (klass != NULL) {
1543 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1544 signature,
1545 overpass_local_mode,
1546 find_static,
1547 find_private);
1548 if (method != NULL) {
1549 return method;
1550 }
1551 klass = klass->super();
1552 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1553 }
1554 return NULL;
1555 }
1556
1557 #ifdef ASSERT
1558 // search through class hierarchy and return true if this class or
1559 // one of the superclasses was redefined
1560 bool InstanceKlass::has_redefined_this_or_super() const {
1561 const Klass* klass = this;
1562 while (klass != NULL) {
1563 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1564 return true;
1565 }
1566 klass = klass->super();
1567 }
1568 return false;
1569 }
1570 #endif
1571
1572 // lookup a method in the default methods list then in all transitive interfaces
1573 // Do NOT return private or static methods
1574 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1575 Symbol* signature) const {
1576 Method* m = NULL;
1577 if (default_methods() != NULL) {
1578 m = find_method(default_methods(), name, signature);
1579 }
1580 // Look up interfaces
1581 if (m == NULL) {
1582 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1583 }
1584 return m;
1585 }
1586
1587 // lookup a method in all the interfaces that this class implements
1588 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1589 // They should only be found in the initial InterfaceMethodRef
1590 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1591 Symbol* signature,
1592 DefaultsLookupMode defaults_mode) const {
1593 Array<Klass*>* all_ifs = transitive_interfaces();
1594 int num_ifs = all_ifs->length();
1595 InstanceKlass *ik = NULL;
1596 for (int i = 0; i < num_ifs; i++) {
1597 ik = InstanceKlass::cast(all_ifs->at(i));
1598 Method* m = ik->lookup_method(name, signature);
1599 if (m != NULL && m->is_public() && !m->is_static() &&
1600 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1601 return m;
1602 }
1603 }
1604 return NULL;
1605 }
1606
1607 /* jni_id_for_impl for jfieldIds only */
1608 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1609 MutexLocker ml(JfieldIdCreation_lock);
1610 // Retry lookup after we got the lock
1611 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1612 if (probe == NULL) {
1613 // Slow case, allocate new static field identifier
1614 probe = new JNIid(this, offset, jni_ids());
1615 set_jni_ids(probe);
1616 }
1617 return probe;
1618 }
1619
1620
1621 /* jni_id_for for jfieldIds only */
1622 JNIid* InstanceKlass::jni_id_for(int offset) {
1623 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1624 if (probe == NULL) {
1625 probe = jni_id_for_impl(offset);
1626 }
1627 return probe;
1628 }
1629
1630 u2 InstanceKlass::enclosing_method_data(int offset) const {
1631 const Array<jushort>* const inner_class_list = inner_classes();
1632 if (inner_class_list == NULL) {
1633 return 0;
1634 }
1635 const int length = inner_class_list->length();
1636 if (length % inner_class_next_offset == 0) {
1637 return 0;
1638 }
1639 const int index = length - enclosing_method_attribute_size;
1640 assert(offset < enclosing_method_attribute_size, "invalid offset");
1641 return inner_class_list->at(index + offset);
1642 }
1643
1644 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1645 u2 method_index) {
1646 Array<jushort>* inner_class_list = inner_classes();
1647 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1648 int length = inner_class_list->length();
1649 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1650 int index = length - enclosing_method_attribute_size;
1651 inner_class_list->at_put(
1652 index + enclosing_method_class_index_offset, class_index);
1653 inner_class_list->at_put(
1654 index + enclosing_method_method_index_offset, method_index);
1655 }
1656 }
1657
1658 // Lookup or create a jmethodID.
1659 // This code is called by the VMThread and JavaThreads so the
1660 // locking has to be done very carefully to avoid deadlocks
1661 // and/or other cache consistency problems.
1662 //
1663 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1664 size_t idnum = (size_t)method_h->method_idnum();
1665 jmethodID* jmeths = methods_jmethod_ids_acquire();
1666 size_t length = 0;
1667 jmethodID id = NULL;
1668
1669 // We use a double-check locking idiom here because this cache is
1670 // performance sensitive. In the normal system, this cache only
1671 // transitions from NULL to non-NULL which is safe because we use
1672 // release_set_methods_jmethod_ids() to advertise the new cache.
1673 // A partially constructed cache should never be seen by a racing
1674 // thread. We also use release_store() to save a new jmethodID
1675 // in the cache so a partially constructed jmethodID should never be
1676 // seen either. Cache reads of existing jmethodIDs proceed without a
1677 // lock, but cache writes of a new jmethodID requires uniqueness and
1678 // creation of the cache itself requires no leaks so a lock is
1679 // generally acquired in those two cases.
1680 //
1681 // If the RedefineClasses() API has been used, then this cache can
1682 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1683 // Cache creation requires no leaks and we require safety between all
1684 // cache accesses and freeing of the old cache so a lock is generally
1685 // acquired when the RedefineClasses() API has been used.
1686
1687 if (jmeths != NULL) {
1688 // the cache already exists
1689 if (!idnum_can_increment()) {
1690 // the cache can't grow so we can just get the current values
1691 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1692 } else {
1693 // cache can grow so we have to be more careful
1694 if (Threads::number_of_threads() == 0 ||
1695 SafepointSynchronize::is_at_safepoint()) {
1696 // we're single threaded or at a safepoint - no locking needed
1697 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1698 } else {
1699 MutexLocker ml(JmethodIdCreation_lock);
1700 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1701 }
1702 }
1703 }
1704 // implied else:
1705 // we need to allocate a cache so default length and id values are good
1706
1707 if (jmeths == NULL || // no cache yet
1708 length <= idnum || // cache is too short
1709 id == NULL) { // cache doesn't contain entry
1710
1711 // This function can be called by the VMThread so we have to do all
1712 // things that might block on a safepoint before grabbing the lock.
1713 // Otherwise, we can deadlock with the VMThread or have a cache
1714 // consistency issue. These vars keep track of what we might have
1715 // to free after the lock is dropped.
1716 jmethodID to_dealloc_id = NULL;
1717 jmethodID* to_dealloc_jmeths = NULL;
1718
1719 // may not allocate new_jmeths or use it if we allocate it
1720 jmethodID* new_jmeths = NULL;
1721 if (length <= idnum) {
1722 // allocate a new cache that might be used
1723 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1724 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1725 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1726 // cache size is stored in element[0], other elements offset by one
1727 new_jmeths[0] = (jmethodID)size;
1728 }
1729
1730 // allocate a new jmethodID that might be used
1731 jmethodID new_id = NULL;
1732 if (method_h->is_old() && !method_h->is_obsolete()) {
1733 // The method passed in is old (but not obsolete), we need to use the current version
1734 Method* current_method = method_with_idnum((int)idnum);
1735 assert(current_method != NULL, "old and but not obsolete, so should exist");
1736 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1737 } else {
1738 // It is the current version of the method or an obsolete method,
1739 // use the version passed in
1740 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1741 }
1742
1743 if (Threads::number_of_threads() == 0 ||
1744 SafepointSynchronize::is_at_safepoint()) {
1745 // we're single threaded or at a safepoint - no locking needed
1746 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1747 &to_dealloc_id, &to_dealloc_jmeths);
1748 } else {
1749 MutexLocker ml(JmethodIdCreation_lock);
1750 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1751 &to_dealloc_id, &to_dealloc_jmeths);
1752 }
1753
1754 // The lock has been dropped so we can free resources.
1755 // Free up either the old cache or the new cache if we allocated one.
1756 if (to_dealloc_jmeths != NULL) {
1757 FreeHeap(to_dealloc_jmeths);
1758 }
1759 // free up the new ID since it wasn't needed
1760 if (to_dealloc_id != NULL) {
1761 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1762 }
1763 }
1764 return id;
1765 }
1766
1767 // Figure out how many jmethodIDs haven't been allocated, and make
1768 // sure space for them is pre-allocated. This makes getting all
1769 // method ids much, much faster with classes with more than 8
1770 // methods, and has a *substantial* effect on performance with jvmti
1771 // code that loads all jmethodIDs for all classes.
1772 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1773 int new_jmeths = 0;
1774 int length = methods()->length();
1775 for (int index = start_offset; index < length; index++) {
1776 Method* m = methods()->at(index);
1777 jmethodID id = m->find_jmethod_id_or_null();
1778 if (id == NULL) {
1779 new_jmeths++;
1780 }
1781 }
1782 if (new_jmeths != 0) {
1783 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1784 }
1785 }
1786
1787 // Common code to fetch the jmethodID from the cache or update the
1788 // cache with the new jmethodID. This function should never do anything
1789 // that causes the caller to go to a safepoint or we can deadlock with
1790 // the VMThread or have cache consistency issues.
1791 //
1792 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1793 size_t idnum, jmethodID new_id,
1794 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1795 jmethodID** to_dealloc_jmeths_p) {
1796 assert(new_id != NULL, "sanity check");
1797 assert(to_dealloc_id_p != NULL, "sanity check");
1798 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1799 assert(Threads::number_of_threads() == 0 ||
1800 SafepointSynchronize::is_at_safepoint() ||
1801 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1802
1803 // reacquire the cache - we are locked, single threaded or at a safepoint
1804 jmethodID* jmeths = methods_jmethod_ids_acquire();
1805 jmethodID id = NULL;
1806 size_t length = 0;
1807
1808 if (jmeths == NULL || // no cache yet
1809 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1810 if (jmeths != NULL) {
1811 // copy any existing entries from the old cache
1812 for (size_t index = 0; index < length; index++) {
1813 new_jmeths[index+1] = jmeths[index+1];
1814 }
1815 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1816 }
1817 release_set_methods_jmethod_ids(jmeths = new_jmeths);
1818 } else {
1819 // fetch jmethodID (if any) from the existing cache
1820 id = jmeths[idnum+1];
1821 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1822 }
1823 if (id == NULL) {
1824 // No matching jmethodID in the existing cache or we have a new
1825 // cache or we just grew the cache. This cache write is done here
1826 // by the first thread to win the foot race because a jmethodID
1827 // needs to be unique once it is generally available.
1828 id = new_id;
1829
1830 // The jmethodID cache can be read while unlocked so we have to
1831 // make sure the new jmethodID is complete before installing it
1832 // in the cache.
1833 OrderAccess::release_store(&jmeths[idnum+1], id);
1834 } else {
1835 *to_dealloc_id_p = new_id; // save new id for later delete
1836 }
1837 return id;
1838 }
1839
1840
1841 // Common code to get the jmethodID cache length and the jmethodID
1842 // value at index idnum if there is one.
1843 //
1844 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1845 size_t idnum, size_t *length_p, jmethodID* id_p) {
1846 assert(cache != NULL, "sanity check");
1847 assert(length_p != NULL, "sanity check");
1848 assert(id_p != NULL, "sanity check");
1849
1850 // cache size is stored in element[0], other elements offset by one
1851 *length_p = (size_t)cache[0];
1852 if (*length_p <= idnum) { // cache is too short
1853 *id_p = NULL;
1854 } else {
1855 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1856 }
1857 }
1858
1859
1860 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1861 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1862 size_t idnum = (size_t)method->method_idnum();
1863 jmethodID* jmeths = methods_jmethod_ids_acquire();
1864 size_t length; // length assigned as debugging crumb
1865 jmethodID id = NULL;
1866 if (jmeths != NULL && // If there is a cache
1867 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1868 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1869 }
1870 return id;
1871 }
1872
1873 inline DependencyContext InstanceKlass::dependencies() {
1874 DependencyContext dep_context(&_dep_context);
1875 return dep_context;
1876 }
1877
1878 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
1879 return dependencies().mark_dependent_nmethods(changes);
1880 }
1881
1882 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1883 dependencies().add_dependent_nmethod(nm);
1884 }
1885
1886 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1887 dependencies().remove_dependent_nmethod(nm, delete_immediately);
1888 }
1889
1890 #ifndef PRODUCT
1891 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1892 dependencies().print_dependent_nmethods(verbose);
1893 }
1894
1895 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1896 return dependencies().is_dependent_nmethod(nm);
1897 }
1898 #endif //PRODUCT
1899
1900 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
1901 clean_implementors_list(is_alive);
1902 clean_method_data(is_alive);
1903
1904 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
1905 DependencyContext dep_context(&_dep_context);
1906 dep_context.expunge_stale_entries();
1907 }
1908
1909 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
1910 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
1911 if (is_interface()) {
1912 if (ClassUnloading) {
1913 Klass* impl = implementor();
1914 if (impl != NULL) {
1915 if (!impl->is_loader_alive(is_alive)) {
1916 // remove this guy
1917 Klass** klass = adr_implementor();
1918 assert(klass != NULL, "null klass");
1919 if (klass != NULL) {
1920 *klass = NULL;
1921 }
1922 }
1923 }
1924 }
1925 }
1926 }
1927
1928 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
1929 for (int m = 0; m < methods()->length(); m++) {
1930 MethodData* mdo = methods()->at(m)->method_data();
1931 if (mdo != NULL) {
1932 mdo->clean_method_data(is_alive);
1933 }
1934 }
1935 }
1936
1937 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
1938 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
1939 ResourceMark rm;
1940 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
1941 return false;
1942 }
1943
1944 Array<Klass*>* local_interfaces = this->local_interfaces();
1945 if (local_interfaces != NULL) {
1946 int length = local_interfaces->length();
1947 for (int i = 0; i < length; i++) {
1948 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
1949 if (!intf->has_passed_fingerprint_check()) {
1950 ResourceMark rm;
1951 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
1952 return false;
1953 }
1954 }
1955 }
1956
1957 return true;
1958 }
1959
1960 bool InstanceKlass::should_store_fingerprint() {
1961 #if INCLUDE_AOT
1962 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
1963 if (CalculateClassFingerprint) {
1964 // (1) We are running AOT to generate a shared library.
1965 return true;
1966 }
1967 if (DumpSharedSpaces) {
1968 // (2) We are running -Xshare:dump to create a shared archive
1969 return true;
1970 }
1971 #endif
1972
1973 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
1974 // but do not store the 64-bit fingerprint to save space.
1975 return false;
1976 }
1977
1978 bool InstanceKlass::has_stored_fingerprint() const {
1979 #if INCLUDE_AOT
1980 return should_store_fingerprint() || is_shared();
1981 #else
1982 return false;
1983 #endif
1984 }
1985
1986 uint64_t InstanceKlass::get_stored_fingerprint() const {
1987 address adr = adr_fingerprint();
1988 if (adr != NULL) {
1989 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
1990 }
1991 return 0;
1992 }
1993
1994 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
1995 address adr = adr_fingerprint();
1996 if (adr != NULL) {
1997 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
1998
1999 ResourceMark rm;
2000 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2001 }
2002 }
2003
2004 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2005 Klass::metaspace_pointers_do(it);
2006
2007 if (log_is_enabled(Trace, cds)) {
2008 ResourceMark rm;
2009 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2010 }
2011
2012 it->push(&_annotations);
2013 it->push((Klass**)&_array_klasses);
2014 it->push(&_constants);
2015 it->push(&_inner_classes);
2016 it->push(&_array_name);
2017 #if INCLUDE_JVMTI
2018 it->push(&_previous_versions);
2019 #endif
2020 it->push(&_methods);
2021 it->push(&_default_methods);
2022 it->push(&_local_interfaces);
2023 it->push(&_transitive_interfaces);
2024 it->push(&_method_ordering);
2025 it->push(&_default_vtable_indices);
2026 it->push(&_fields);
2027
2028 if (itable_length() > 0) {
2029 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2030 int method_table_offset_in_words = ioe->offset()/wordSize;
2031 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2032 / itableOffsetEntry::size();
2033
2034 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2035 if (ioe->interface_klass() != NULL) {
2036 it->push(ioe->interface_klass_addr());
2037 itableMethodEntry* ime = ioe->first_method_entry(this);
2038 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2039 for (int index = 0; index < n; index ++) {
2040 it->push(ime[index].method_addr());
2041 }
2042 }
2043 }
2044 }
2045 }
2046
2047 void InstanceKlass::remove_unshareable_info() {
2048 Klass::remove_unshareable_info();
2049
2050 if (is_in_error_state()) {
2051 // Classes are attempted to link during dumping and may fail,
2052 // but these classes are still in the dictionary and class list in CLD.
2053 // Check in_error state first because in_error is > linked state, so
2054 // is_linked() is true.
2055 // If there's a linking error, there is nothing else to remove.
2056 return;
2057 }
2058
2059 // Unlink the class
2060 if (is_linked()) {
2061 unlink_class();
2062 }
2063 init_implementor();
2064
2065 constants()->remove_unshareable_info();
2066
2067 for (int i = 0; i < methods()->length(); i++) {
2068 Method* m = methods()->at(i);
2069 m->remove_unshareable_info();
2070 }
2071
2072 // do array classes also.
2073 if (array_klasses() != NULL) {
2074 array_klasses()->remove_unshareable_info();
2075 }
2076
2077 // These are not allocated from metaspace, but they should should all be empty
2078 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2079 guarantee(_source_debug_extension == NULL, "must be");
2080 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2081 guarantee(_osr_nmethods_head == NULL, "must be");
2082
2083 #if INCLUDE_JVMTI
2084 guarantee(_breakpoints == NULL, "must be");
2085 guarantee(_previous_versions == NULL, "must be");
2086 #endif
2087
2088 _init_thread = NULL;
2089 _methods_jmethod_ids = NULL;
2090 _jni_ids = NULL;
2091 _oop_map_cache = NULL;
2092 }
2093
2094 void InstanceKlass::remove_java_mirror() {
2095 Klass::remove_java_mirror();
2096
2097 // do array classes also.
2098 if (array_klasses() != NULL) {
2099 array_klasses()->remove_java_mirror();
2100 }
2101 }
2102
2103 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2104 set_package(loader_data, CHECK);
2105 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2106
2107 Array<Method*>* methods = this->methods();
2108 int num_methods = methods->length();
2109 for (int index2 = 0; index2 < num_methods; ++index2) {
2110 methodHandle m(THREAD, methods->at(index2));
2111 m->restore_unshareable_info(CHECK);
2112 }
2113 if (JvmtiExport::has_redefined_a_class()) {
2114 // Reinitialize vtable because RedefineClasses may have changed some
2115 // entries in this vtable for super classes so the CDS vtable might
2116 // point to old or obsolete entries. RedefineClasses doesn't fix up
2117 // vtables in the shared system dictionary, only the main one.
2118 // It also redefines the itable too so fix that too.
2119 ResourceMark rm(THREAD);
2120 vtable().initialize_vtable(false, CHECK);
2121 itable().initialize_itable(false, CHECK);
2122 }
2123
2124 // restore constant pool resolved references
2125 constants()->restore_unshareable_info(CHECK);
2126
2127 if (array_klasses() != NULL) {
2128 // Array classes have null protection domain.
2129 // --> see ArrayKlass::complete_create_array_klass()
2130 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2131 }
2132 }
2133
2134 // returns true IFF is_in_error_state() has been changed as a result of this call.
2135 bool InstanceKlass::check_sharing_error_state() {
2136 assert(DumpSharedSpaces, "should only be called during dumping");
2137 bool old_state = is_in_error_state();
2138
2139 if (!is_in_error_state()) {
2140 bool bad = false;
2141 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2142 if (sup->is_in_error_state()) {
2143 bad = true;
2144 break;
2145 }
2146 }
2147 if (!bad) {
2148 Array<Klass*>* interfaces = transitive_interfaces();
2149 for (int i = 0; i < interfaces->length(); i++) {
2150 Klass* iface = interfaces->at(i);
2151 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2152 bad = true;
2153 break;
2154 }
2155 }
2156 }
2157
2158 if (bad) {
2159 set_in_error_state();
2160 }
2161 }
2162
2163 return (old_state != is_in_error_state());
2164 }
2165
2166 #if INCLUDE_JVMTI
2167 static void clear_all_breakpoints(Method* m) {
2168 m->clear_all_breakpoints();
2169 }
2170 #endif
2171
2172 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2173 // notify the debugger
2174 if (JvmtiExport::should_post_class_unload()) {
2175 JvmtiExport::post_class_unload(ik);
2176 }
2177
2178 // notify ClassLoadingService of class unload
2179 ClassLoadingService::notify_class_unloaded(ik);
2180 }
2181
2182 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2183 // Clean up C heap
2184 ik->release_C_heap_structures();
2185 ik->constants()->release_C_heap_structures();
2186 }
2187
2188 void InstanceKlass::release_C_heap_structures() {
2189 // Can't release the constant pool here because the constant pool can be
2190 // deallocated separately from the InstanceKlass for default methods and
2191 // redefine classes.
2192
2193 // Deallocate oop map cache
2194 if (_oop_map_cache != NULL) {
2195 delete _oop_map_cache;
2196 _oop_map_cache = NULL;
2197 }
2198
2199 // Deallocate JNI identifiers for jfieldIDs
2200 JNIid::deallocate(jni_ids());
2201 set_jni_ids(NULL);
2202
2203 jmethodID* jmeths = methods_jmethod_ids_acquire();
2204 if (jmeths != (jmethodID*)NULL) {
2205 release_set_methods_jmethod_ids(NULL);
2206 FreeHeap(jmeths);
2207 }
2208
2209 // Release dependencies.
2210 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2211 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2212 // context can contain live dependencies, since there's a race between nmethod &
2213 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2214 // dependencies aren't removed from the context associated with the class (see
2215 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2216 // live dependencies pointing to unloaded nmethods and causes a crash in
2217 // DC::remove_all_dependents() when it touches unloaded nmethod.
2218 dependencies().wipe();
2219
2220 #if INCLUDE_JVMTI
2221 // Deallocate breakpoint records
2222 if (breakpoints() != 0x0) {
2223 methods_do(clear_all_breakpoints);
2224 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2225 }
2226
2227 // deallocate the cached class file
2228 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_space(_cached_class_file)) {
2229 os::free(_cached_class_file);
2230 _cached_class_file = NULL;
2231 }
2232 #endif
2233
2234 // Decrement symbol reference counts associated with the unloaded class.
2235 if (_name != NULL) _name->decrement_refcount();
2236 // unreference array name derived from this class name (arrays of an unloaded
2237 // class can't be referenced anymore).
2238 if (_array_name != NULL) _array_name->decrement_refcount();
2239 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2240
2241 assert(_total_instanceKlass_count >= 1, "Sanity check");
2242 Atomic::dec(&_total_instanceKlass_count);
2243 }
2244
2245 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2246 if (array == NULL) {
2247 _source_debug_extension = NULL;
2248 } else {
2249 // Adding one to the attribute length in order to store a null terminator
2250 // character could cause an overflow because the attribute length is
2251 // already coded with an u4 in the classfile, but in practice, it's
2252 // unlikely to happen.
2253 assert((length+1) > length, "Overflow checking");
2254 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2255 for (int i = 0; i < length; i++) {
2256 sde[i] = array[i];
2257 }
2258 sde[length] = '\0';
2259 _source_debug_extension = sde;
2260 }
2261 }
2262
2263 address InstanceKlass::static_field_addr(int offset) {
2264 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2265 }
2266
2267
2268 const char* InstanceKlass::signature_name() const {
2269 int hash_len = 0;
2270 char hash_buf[40];
2271
2272 // If this is an anonymous class, append a hash to make the name unique
2273 if (is_anonymous()) {
2274 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2275 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2276 hash_len = (int)strlen(hash_buf);
2277 }
2278
2279 // Get the internal name as a c string
2280 const char* src = (const char*) (name()->as_C_string());
2281 const int src_length = (int)strlen(src);
2282
2283 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2284
2285 // Add L as type indicator
2286 int dest_index = 0;
2287 dest[dest_index++] = 'L';
2288
2289 // Add the actual class name
2290 for (int src_index = 0; src_index < src_length; ) {
2291 dest[dest_index++] = src[src_index++];
2292 }
2293
2294 // If we have a hash, append it
2295 for (int hash_index = 0; hash_index < hash_len; ) {
2296 dest[dest_index++] = hash_buf[hash_index++];
2297 }
2298
2299 // Add the semicolon and the NULL
2300 dest[dest_index++] = ';';
2301 dest[dest_index] = '\0';
2302 return dest;
2303 }
2304
2305 // Used to obtain the package name from a fully qualified class name.
2306 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2307 if (name == NULL) {
2308 return NULL;
2309 } else {
2310 if (name->utf8_length() <= 0) {
2311 return NULL;
2312 }
2313 ResourceMark rm;
2314 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2315 if (package_name == NULL) {
2316 return NULL;
2317 }
2318 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2319 return pkg_name;
2320 }
2321 }
2322
2323 ModuleEntry* InstanceKlass::module() const {
2324 if (!in_unnamed_package()) {
2325 return _package_entry->module();
2326 }
2327 const Klass* host = host_klass();
2328 if (host == NULL) {
2329 return class_loader_data()->unnamed_module();
2330 }
2331 return host->class_loader_data()->unnamed_module();
2332 }
2333
2334 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2335
2336 // ensure java/ packages only loaded by boot or platform builtin loaders
2337 Handle class_loader(THREAD, loader_data->class_loader());
2338 check_prohibited_package(name(), class_loader, CHECK);
2339
2340 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2341
2342 if (pkg_name != NULL && loader_data != NULL) {
2343
2344 // Find in class loader's package entry table.
2345 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2346
2347 // If the package name is not found in the loader's package
2348 // entry table, it is an indication that the package has not
2349 // been defined. Consider it defined within the unnamed module.
2350 if (_package_entry == NULL) {
2351 ResourceMark rm;
2352
2353 if (!ModuleEntryTable::javabase_defined()) {
2354 // Before java.base is defined during bootstrapping, define all packages in
2355 // the java.base module. If a non-java.base package is erroneously placed
2356 // in the java.base module it will be caught later when java.base
2357 // is defined by ModuleEntryTable::verify_javabase_packages check.
2358 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2359 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2360 } else {
2361 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2362 _package_entry = loader_data->packages()->lookup(pkg_name,
2363 loader_data->unnamed_module());
2364 }
2365
2366 // A package should have been successfully created
2367 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2368 name()->as_C_string(), loader_data->loader_name());
2369 }
2370
2371 if (log_is_enabled(Debug, module)) {
2372 ResourceMark rm;
2373 ModuleEntry* m = _package_entry->module();
2374 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2375 external_name(),
2376 pkg_name->as_C_string(),
2377 loader_data->loader_name(),
2378 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2379 }
2380 } else {
2381 ResourceMark rm;
2382 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2383 external_name(),
2384 (loader_data != NULL) ? loader_data->loader_name() : "NULL",
2385 UNNAMED_MODULE);
2386 }
2387 }
2388
2389
2390 // different versions of is_same_class_package
2391
2392 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2393 oop classloader1 = this->class_loader();
2394 PackageEntry* classpkg1 = this->package();
2395 if (class2->is_objArray_klass()) {
2396 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2397 }
2398
2399 oop classloader2;
2400 PackageEntry* classpkg2;
2401 if (class2->is_instance_klass()) {
2402 classloader2 = class2->class_loader();
2403 classpkg2 = class2->package();
2404 } else {
2405 assert(class2->is_typeArray_klass(), "should be type array");
2406 classloader2 = NULL;
2407 classpkg2 = NULL;
2408 }
2409
2410 // Same package is determined by comparing class loader
2411 // and package entries. Both must be the same. This rule
2412 // applies even to classes that are defined in the unnamed
2413 // package, they still must have the same class loader.
2414 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2415 return true;
2416 }
2417
2418 return false;
2419 }
2420
2421 // return true if this class and other_class are in the same package. Classloader
2422 // and classname information is enough to determine a class's package
2423 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2424 const Symbol* other_class_name) const {
2425 if (class_loader() != other_class_loader) {
2426 return false;
2427 }
2428 if (name()->fast_compare(other_class_name) == 0) {
2429 return true;
2430 }
2431
2432 {
2433 ResourceMark rm;
2434
2435 bool bad_class_name = false;
2436 const char* other_pkg =
2437 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2438 if (bad_class_name) {
2439 return false;
2440 }
2441 // Check that package_from_name() returns NULL, not "", if there is no package.
2442 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2443
2444 const Symbol* const this_package_name =
2445 this->package() != NULL ? this->package()->name() : NULL;
2446
2447 if (this_package_name == NULL || other_pkg == NULL) {
2448 // One of the two doesn't have a package. Only return true if the other
2449 // one also doesn't have a package.
2450 return (const char*)this_package_name == other_pkg;
2451 }
2452
2453 // Check if package is identical
2454 return this_package_name->equals(other_pkg);
2455 }
2456 }
2457
2458 // Returns true iff super_method can be overridden by a method in targetclassname
2459 // See JLS 3rd edition 8.4.6.1
2460 // Assumes name-signature match
2461 // "this" is InstanceKlass of super_method which must exist
2462 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2463 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2464 // Private methods can not be overridden
2465 if (super_method->is_private()) {
2466 return false;
2467 }
2468 // If super method is accessible, then override
2469 if ((super_method->is_protected()) ||
2470 (super_method->is_public())) {
2471 return true;
2472 }
2473 // Package-private methods are not inherited outside of package
2474 assert(super_method->is_package_private(), "must be package private");
2475 return(is_same_class_package(targetclassloader(), targetclassname));
2476 }
2477
2478 // Only boot and platform class loaders can define classes in "java/" packages.
2479 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2480 Handle class_loader,
2481 TRAPS) {
2482 if (!class_loader.is_null() &&
2483 !SystemDictionary::is_platform_class_loader(class_loader()) &&
2484 class_name != NULL) {
2485 ResourceMark rm(THREAD);
2486 char* name = class_name->as_C_string();
2487 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2488 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2489 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2490 name = pkg_name->as_C_string();
2491 const char* class_loader_name = SystemDictionary::loader_name(class_loader());
2492 StringUtils::replace_no_expand(name, "/", ".");
2493 const char* msg_text1 = "Class loader (instance of): ";
2494 const char* msg_text2 = " tried to load prohibited package name: ";
2495 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2496 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2497 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2498 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2499 }
2500 }
2501 return;
2502 }
2503
2504 // tell if two classes have the same enclosing class (at package level)
2505 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2506 if (class2 == this) return true;
2507 if (!class2->is_instance_klass()) return false;
2508
2509 // must be in same package before we try anything else
2510 if (!is_same_class_package(class2))
2511 return false;
2512
2513 // As long as there is an outer_this.getEnclosingClass,
2514 // shift the search outward.
2515 const InstanceKlass* outer_this = this;
2516 for (;;) {
2517 // As we walk along, look for equalities between outer_this and class2.
2518 // Eventually, the walks will terminate as outer_this stops
2519 // at the top-level class around the original class.
2520 bool ignore_inner_is_member;
2521 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2522 CHECK_false);
2523 if (next == NULL) break;
2524 if (next == class2) return true;
2525 outer_this = InstanceKlass::cast(next);
2526 }
2527
2528 // Now do the same for class2.
2529 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2530 for (;;) {
2531 bool ignore_inner_is_member;
2532 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2533 CHECK_false);
2534 if (next == NULL) break;
2535 // Might as well check the new outer against all available values.
2536 if (next == this) return true;
2537 if (next == outer_this) return true;
2538 outer2 = InstanceKlass::cast(next);
2539 }
2540
2541 // If by this point we have not found an equality between the
2542 // two classes, we know they are in separate package members.
2543 return false;
2544 }
2545
2546 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2547 constantPoolHandle i_cp(THREAD, constants());
2548 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2549 int ioff = iter.inner_class_info_index();
2550 if (ioff != 0) {
2551 // Check to see if the name matches the class we're looking for
2552 // before attempting to find the class.
2553 if (i_cp->klass_name_at_matches(this, ioff)) {
2554 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2555 if (this == inner_klass) {
2556 *ooff = iter.outer_class_info_index();
2557 *noff = iter.inner_name_index();
2558 return true;
2559 }
2560 }
2561 }
2562 }
2563 return false;
2564 }
2565
2566 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2567 InstanceKlass* outer_klass = NULL;
2568 *inner_is_member = false;
2569 int ooff = 0, noff = 0;
2570 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2571 if (has_inner_classes_attr) {
2572 constantPoolHandle i_cp(THREAD, constants());
2573 if (ooff != 0) {
2574 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2575 outer_klass = InstanceKlass::cast(ok);
2576 *inner_is_member = true;
2577 }
2578 if (NULL == outer_klass) {
2579 // It may be anonymous; try for that.
2580 int encl_method_class_idx = enclosing_method_class_index();
2581 if (encl_method_class_idx != 0) {
2582 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2583 outer_klass = InstanceKlass::cast(ok);
2584 *inner_is_member = false;
2585 }
2586 }
2587 }
2588
2589 // If no inner class attribute found for this class.
2590 if (NULL == outer_klass) return NULL;
2591
2592 // Throws an exception if outer klass has not declared k as an inner klass
2593 // We need evidence that each klass knows about the other, or else
2594 // the system could allow a spoof of an inner class to gain access rights.
2595 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2596 return outer_klass;
2597 }
2598
2599 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2600 jint access = access_flags().as_int();
2601
2602 // But check if it happens to be member class.
2603 InnerClassesIterator iter(this);
2604 for (; !iter.done(); iter.next()) {
2605 int ioff = iter.inner_class_info_index();
2606 // Inner class attribute can be zero, skip it.
2607 // Strange but true: JVM spec. allows null inner class refs.
2608 if (ioff == 0) continue;
2609
2610 // only look at classes that are already loaded
2611 // since we are looking for the flags for our self.
2612 Symbol* inner_name = constants()->klass_name_at(ioff);
2613 if (name() == inner_name) {
2614 // This is really a member class.
2615 access = iter.inner_access_flags();
2616 break;
2617 }
2618 }
2619 // Remember to strip ACC_SUPER bit
2620 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2621 }
2622
2623 jint InstanceKlass::jvmti_class_status() const {
2624 jint result = 0;
2625
2626 if (is_linked()) {
2627 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2628 }
2629
2630 if (is_initialized()) {
2631 assert(is_linked(), "Class status is not consistent");
2632 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2633 }
2634 if (is_in_error_state()) {
2635 result |= JVMTI_CLASS_STATUS_ERROR;
2636 }
2637 return result;
2638 }
2639
2640 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2641 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2642 int method_table_offset_in_words = ioe->offset()/wordSize;
2643 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2644 / itableOffsetEntry::size();
2645
2646 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2647 // If the interface isn't implemented by the receiver class,
2648 // the VM should throw IncompatibleClassChangeError.
2649 if (cnt >= nof_interfaces) {
2650 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2651 }
2652
2653 Klass* ik = ioe->interface_klass();
2654 if (ik == holder) break;
2655 }
2656
2657 itableMethodEntry* ime = ioe->first_method_entry(this);
2658 Method* m = ime[index].method();
2659 if (m == NULL) {
2660 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2661 }
2662 return m;
2663 }
2664
2665
2666 #if INCLUDE_JVMTI
2667 // update default_methods for redefineclasses for methods that are
2668 // not yet in the vtable due to concurrent subclass define and superinterface
2669 // redefinition
2670 // Note: those in the vtable, should have been updated via adjust_method_entries
2671 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2672 // search the default_methods for uses of either obsolete or EMCP methods
2673 if (default_methods() != NULL) {
2674 for (int index = 0; index < default_methods()->length(); index ++) {
2675 Method* old_method = default_methods()->at(index);
2676 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2677 continue; // skip uninteresting entries
2678 }
2679 assert(!old_method->is_deleted(), "default methods may not be deleted");
2680
2681 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2682
2683 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2684 assert(old_method != new_method, "sanity check");
2685
2686 default_methods()->at_put(index, new_method);
2687 if (log_is_enabled(Info, redefine, class, update)) {
2688 ResourceMark rm;
2689 if (!(*trace_name_printed)) {
2690 log_info(redefine, class, update)
2691 ("adjust: klassname=%s default methods from name=%s",
2692 external_name(), old_method->method_holder()->external_name());
2693 *trace_name_printed = true;
2694 }
2695 log_debug(redefine, class, update, vtables)
2696 ("default method update: %s(%s) ",
2697 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2698 }
2699 }
2700 }
2701 }
2702 #endif // INCLUDE_JVMTI
2703
2704 // On-stack replacement stuff
2705 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2706 // only one compilation can be active
2707 {
2708 // This is a short non-blocking critical region, so the no safepoint check is ok.
2709 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2710 assert(n->is_osr_method(), "wrong kind of nmethod");
2711 n->set_osr_link(osr_nmethods_head());
2712 set_osr_nmethods_head(n);
2713 // Raise the highest osr level if necessary
2714 if (TieredCompilation) {
2715 Method* m = n->method();
2716 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2717 }
2718 }
2719
2720 // Get rid of the osr methods for the same bci that have lower levels.
2721 if (TieredCompilation) {
2722 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2723 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2724 if (inv != NULL && inv->is_in_use()) {
2725 inv->make_not_entrant();
2726 }
2727 }
2728 }
2729 }
2730
2731 // Remove osr nmethod from the list. Return true if found and removed.
2732 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2733 // This is a short non-blocking critical region, so the no safepoint check is ok.
2734 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2735 assert(n->is_osr_method(), "wrong kind of nmethod");
2736 nmethod* last = NULL;
2737 nmethod* cur = osr_nmethods_head();
2738 int max_level = CompLevel_none; // Find the max comp level excluding n
2739 Method* m = n->method();
2740 // Search for match
2741 bool found = false;
2742 while(cur != NULL && cur != n) {
2743 if (TieredCompilation && m == cur->method()) {
2744 // Find max level before n
2745 max_level = MAX2(max_level, cur->comp_level());
2746 }
2747 last = cur;
2748 cur = cur->osr_link();
2749 }
2750 nmethod* next = NULL;
2751 if (cur == n) {
2752 found = true;
2753 next = cur->osr_link();
2754 if (last == NULL) {
2755 // Remove first element
2756 set_osr_nmethods_head(next);
2757 } else {
2758 last->set_osr_link(next);
2759 }
2760 }
2761 n->set_osr_link(NULL);
2762 if (TieredCompilation) {
2763 cur = next;
2764 while (cur != NULL) {
2765 // Find max level after n
2766 if (m == cur->method()) {
2767 max_level = MAX2(max_level, cur->comp_level());
2768 }
2769 cur = cur->osr_link();
2770 }
2771 m->set_highest_osr_comp_level(max_level);
2772 }
2773 return found;
2774 }
2775
2776 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2777 // This is a short non-blocking critical region, so the no safepoint check is ok.
2778 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2779 nmethod* osr = osr_nmethods_head();
2780 int found = 0;
2781 while (osr != NULL) {
2782 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2783 if (osr->method() == m) {
2784 osr->mark_for_deoptimization();
2785 found++;
2786 }
2787 osr = osr->osr_link();
2788 }
2789 return found;
2790 }
2791
2792 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2793 // This is a short non-blocking critical region, so the no safepoint check is ok.
2794 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2795 nmethod* osr = osr_nmethods_head();
2796 nmethod* best = NULL;
2797 while (osr != NULL) {
2798 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2799 // There can be a time when a c1 osr method exists but we are waiting
2800 // for a c2 version. When c2 completes its osr nmethod we will trash
2801 // the c1 version and only be able to find the c2 version. However
2802 // while we overflow in the c1 code at back branches we don't want to
2803 // try and switch to the same code as we are already running
2804
2805 if (osr->method() == m &&
2806 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2807 if (match_level) {
2808 if (osr->comp_level() == comp_level) {
2809 // Found a match - return it.
2810 return osr;
2811 }
2812 } else {
2813 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2814 if (osr->comp_level() == CompLevel_highest_tier) {
2815 // Found the best possible - return it.
2816 return osr;
2817 }
2818 best = osr;
2819 }
2820 }
2821 }
2822 osr = osr->osr_link();
2823 }
2824 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2825 return best;
2826 }
2827 return NULL;
2828 }
2829
2830 // -----------------------------------------------------------------------------------------------------
2831 // Printing
2832
2833 #ifndef PRODUCT
2834
2835 #define BULLET " - "
2836
2837 static const char* state_names[] = {
2838 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2839 };
2840
2841 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2842 for (int i = 0; i < len; i++) {
2843 intptr_t e = start[i];
2844 st->print("%d : " INTPTR_FORMAT, i, e);
2845 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2846 st->print(" ");
2847 ((Metadata*)e)->print_value_on(st);
2848 }
2849 st->cr();
2850 }
2851 }
2852
2853 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
2854 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
2855 }
2856
2857 void InstanceKlass::print_on(outputStream* st) const {
2858 assert(is_klass(), "must be klass");
2859 Klass::print_on(st);
2860
2861 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2862 st->print(BULLET"klass size: %d", size()); st->cr();
2863 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2864 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
2865 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2866 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2867 st->print(BULLET"sub: ");
2868 Klass* sub = subklass();
2869 int n;
2870 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2871 if (n < MaxSubklassPrintSize) {
2872 sub->print_value_on(st);
2873 st->print(" ");
2874 }
2875 }
2876 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
2877 st->cr();
2878
2879 if (is_interface()) {
2880 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2881 if (nof_implementors() == 1) {
2882 st->print_cr(BULLET"implementor: ");
2883 st->print(" ");
2884 implementor()->print_value_on(st);
2885 st->cr();
2886 }
2887 }
2888
2889 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2890 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2891 if (Verbose || WizardMode) {
2892 Array<Method*>* method_array = methods();
2893 for (int i = 0; i < method_array->length(); i++) {
2894 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2895 }
2896 }
2897 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2898 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
2899 if (Verbose && default_methods() != NULL) {
2900 Array<Method*>* method_array = default_methods();
2901 for (int i = 0; i < method_array->length(); i++) {
2902 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2903 }
2904 }
2905 if (default_vtable_indices() != NULL) {
2906 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
2907 }
2908 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2909 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2910 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
2911 if (class_loader_data() != NULL) {
2912 st->print(BULLET"class loader data: ");
2913 class_loader_data()->print_value_on(st);
2914 st->cr();
2915 }
2916 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
2917 if (source_file_name() != NULL) {
2918 st->print(BULLET"source file: ");
2919 source_file_name()->print_value_on(st);
2920 st->cr();
2921 }
2922 if (source_debug_extension() != NULL) {
2923 st->print(BULLET"source debug extension: ");
2924 st->print("%s", source_debug_extension());
2925 st->cr();
2926 }
2927 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
2928 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
2929 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
2930 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
2931 {
2932 bool have_pv = false;
2933 // previous versions are linked together through the InstanceKlass
2934 for (InstanceKlass* pv_node = previous_versions();
2935 pv_node != NULL;
2936 pv_node = pv_node->previous_versions()) {
2937 if (!have_pv)
2938 st->print(BULLET"previous version: ");
2939 have_pv = true;
2940 pv_node->constants()->print_value_on(st);
2941 }
2942 if (have_pv) st->cr();
2943 }
2944
2945 if (generic_signature() != NULL) {
2946 st->print(BULLET"generic signature: ");
2947 generic_signature()->print_value_on(st);
2948 st->cr();
2949 }
2950 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
2951 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
2952 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
2953 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
2954 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
2955 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
2956 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2957 FieldPrinter print_static_field(st);
2958 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2959 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2960 FieldPrinter print_nonstatic_field(st);
2961 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
2962 ik->do_nonstatic_fields(&print_nonstatic_field);
2963
2964 st->print(BULLET"non-static oop maps: ");
2965 OopMapBlock* map = start_of_nonstatic_oop_maps();
2966 OopMapBlock* end_map = map + nonstatic_oop_map_count();
2967 while (map < end_map) {
2968 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2969 map++;
2970 }
2971 st->cr();
2972 }
2973
2974 #endif //PRODUCT
2975
2976 void InstanceKlass::print_value_on(outputStream* st) const {
2977 assert(is_klass(), "must be klass");
2978 if (Verbose || WizardMode) access_flags().print_on(st);
2979 name()->print_value_on(st);
2980 }
2981
2982 #ifndef PRODUCT
2983
2984 void FieldPrinter::do_field(fieldDescriptor* fd) {
2985 _st->print(BULLET);
2986 if (_obj == NULL) {
2987 fd->print_on(_st);
2988 _st->cr();
2989 } else {
2990 fd->print_on_for(_st, _obj);
2991 _st->cr();
2992 }
2993 }
2994
2995
2996 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
2997 Klass::oop_print_on(obj, st);
2998
2999 if (this == SystemDictionary::String_klass()) {
3000 typeArrayOop value = java_lang_String::value(obj);
3001 juint length = java_lang_String::length(obj);
3002 if (value != NULL &&
3003 value->is_typeArray() &&
3004 length <= (juint) value->length()) {
3005 st->print(BULLET"string: ");
3006 java_lang_String::print(obj, st);
3007 st->cr();
3008 if (!WizardMode) return; // that is enough
3009 }
3010 }
3011
3012 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3013 FieldPrinter print_field(st, obj);
3014 do_nonstatic_fields(&print_field);
3015
3016 if (this == SystemDictionary::Class_klass()) {
3017 st->print(BULLET"signature: ");
3018 java_lang_Class::print_signature(obj, st);
3019 st->cr();
3020 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3021 st->print(BULLET"fake entry for mirror: ");
3022 mirrored_klass->print_value_on_maybe_null(st);
3023 st->cr();
3024 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3025 st->print(BULLET"fake entry for array: ");
3026 array_klass->print_value_on_maybe_null(st);
3027 st->cr();
3028 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3029 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3030 Klass* real_klass = java_lang_Class::as_Klass(obj);
3031 if (real_klass != NULL && real_klass->is_instance_klass()) {
3032 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3033 }
3034 } else if (this == SystemDictionary::MethodType_klass()) {
3035 st->print(BULLET"signature: ");
3036 java_lang_invoke_MethodType::print_signature(obj, st);
3037 st->cr();
3038 }
3039 }
3040
3041 #endif //PRODUCT
3042
3043 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3044 st->print("a ");
3045 name()->print_value_on(st);
3046 obj->print_address_on(st);
3047 if (this == SystemDictionary::String_klass()
3048 && java_lang_String::value(obj) != NULL) {
3049 ResourceMark rm;
3050 int len = java_lang_String::length(obj);
3051 int plen = (len < 24 ? len : 12);
3052 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3053 st->print(" = \"%s\"", str);
3054 if (len > plen)
3055 st->print("...[%d]", len);
3056 } else if (this == SystemDictionary::Class_klass()) {
3057 Klass* k = java_lang_Class::as_Klass(obj);
3058 st->print(" = ");
3059 if (k != NULL) {
3060 k->print_value_on(st);
3061 } else {
3062 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3063 st->print("%s", tname ? tname : "type?");
3064 }
3065 } else if (this == SystemDictionary::MethodType_klass()) {
3066 st->print(" = ");
3067 java_lang_invoke_MethodType::print_signature(obj, st);
3068 } else if (java_lang_boxing_object::is_instance(obj)) {
3069 st->print(" = ");
3070 java_lang_boxing_object::print(obj, st);
3071 } else if (this == SystemDictionary::LambdaForm_klass()) {
3072 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3073 if (vmentry != NULL) {
3074 st->print(" => ");
3075 vmentry->print_value_on(st);
3076 }
3077 } else if (this == SystemDictionary::MemberName_klass()) {
3078 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3079 if (vmtarget != NULL) {
3080 st->print(" = ");
3081 vmtarget->print_value_on(st);
3082 } else {
3083 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3084 st->print(".");
3085 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3086 }
3087 }
3088 }
3089
3090 const char* InstanceKlass::internal_name() const {
3091 return external_name();
3092 }
3093
3094 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3095 const char* module_name,
3096 const ClassFileStream* cfs) const {
3097 if (!log_is_enabled(Info, class, load)) {
3098 return;
3099 }
3100
3101 ResourceMark rm;
3102 LogMessage(class, load) msg;
3103 stringStream info_stream;
3104
3105 // Name and class hierarchy info
3106 info_stream.print("%s", external_name());
3107
3108 // Source
3109 if (cfs != NULL) {
3110 if (cfs->source() != NULL) {
3111 if (module_name != NULL) {
3112 if (ClassLoader::is_jrt(cfs->source())) {
3113 info_stream.print(" source: jrt:/%s", module_name);
3114 } else {
3115 info_stream.print(" source: %s", cfs->source());
3116 }
3117 } else {
3118 info_stream.print(" source: %s", cfs->source());
3119 }
3120 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3121 Thread* THREAD = Thread::current();
3122 Klass* caller =
3123 THREAD->is_Java_thread()
3124 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3125 : NULL;
3126 // caller can be NULL, for example, during a JVMTI VM_Init hook
3127 if (caller != NULL) {
3128 info_stream.print(" source: instance of %s", caller->external_name());
3129 } else {
3130 // source is unknown
3131 }
3132 } else {
3133 oop class_loader = loader_data->class_loader();
3134 info_stream.print(" source: %s", class_loader->klass()->external_name());
3135 }
3136 } else {
3137 info_stream.print(" source: shared objects file");
3138 }
3139
3140 msg.info("%s", info_stream.as_string());
3141
3142 if (log_is_enabled(Debug, class, load)) {
3143 stringStream debug_stream;
3144
3145 // Class hierarchy info
3146 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3147 p2i(this), p2i(superklass()));
3148
3149 // Interfaces
3150 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3151 debug_stream.print(" interfaces:");
3152 int length = local_interfaces()->length();
3153 for (int i = 0; i < length; i++) {
3154 debug_stream.print(" " INTPTR_FORMAT,
3155 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3156 }
3157 }
3158
3159 // Class loader
3160 debug_stream.print(" loader: [");
3161 loader_data->print_value_on(&debug_stream);
3162 debug_stream.print("]");
3163
3164 // Classfile checksum
3165 if (cfs) {
3166 debug_stream.print(" bytes: %d checksum: %08x",
3167 cfs->length(),
3168 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3169 cfs->length()));
3170 }
3171
3172 msg.debug("%s", debug_stream.as_string());
3173 }
3174 }
3175
3176 #if INCLUDE_SERVICES
3177 // Size Statistics
3178 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3179 Klass::collect_statistics(sz);
3180
3181 sz->_inst_size = wordSize * size_helper();
3182 sz->_vtab_bytes = wordSize * vtable_length();
3183 sz->_itab_bytes = wordSize * itable_length();
3184 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3185
3186 int n = 0;
3187 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3188 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3189 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3190 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3191 n += (sz->_fields_bytes = sz->count_array(fields()));
3192 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3193 sz->_ro_bytes += n;
3194
3195 const ConstantPool* cp = constants();
3196 if (cp) {
3197 cp->collect_statistics(sz);
3198 }
3199
3200 const Annotations* anno = annotations();
3201 if (anno) {
3202 anno->collect_statistics(sz);
3203 }
3204
3205 const Array<Method*>* methods_array = methods();
3206 if (methods()) {
3207 for (int i = 0; i < methods_array->length(); i++) {
3208 Method* method = methods_array->at(i);
3209 if (method) {
3210 sz->_method_count ++;
3211 method->collect_statistics(sz);
3212 }
3213 }
3214 }
3215 }
3216 #endif // INCLUDE_SERVICES
3217
3218 // Verification
3219
3220 class VerifyFieldClosure: public OopClosure {
3221 protected:
3222 template <class T> void do_oop_work(T* p) {
3223 oop obj = oopDesc::load_decode_heap_oop(p);
3224 if (!oopDesc::is_oop_or_null(obj)) {
3225 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3226 Universe::print_on(tty);
3227 guarantee(false, "boom");
3228 }
3229 }
3230 public:
3231 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3232 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3233 };
3234
3235 void InstanceKlass::verify_on(outputStream* st) {
3236 #ifndef PRODUCT
3237 // Avoid redundant verifies, this really should be in product.
3238 if (_verify_count == Universe::verify_count()) return;
3239 _verify_count = Universe::verify_count();
3240 #endif
3241
3242 // Verify Klass
3243 Klass::verify_on(st);
3244
3245 // Verify that klass is present in ClassLoaderData
3246 guarantee(class_loader_data()->contains_klass(this),
3247 "this class isn't found in class loader data");
3248
3249 // Verify vtables
3250 if (is_linked()) {
3251 // $$$ This used to be done only for m/s collections. Doing it
3252 // always seemed a valid generalization. (DLD -- 6/00)
3253 vtable().verify(st);
3254 }
3255
3256 // Verify first subklass
3257 if (subklass() != NULL) {
3258 guarantee(subklass()->is_klass(), "should be klass");
3259 }
3260
3261 // Verify siblings
3262 Klass* super = this->super();
3263 Klass* sib = next_sibling();
3264 if (sib != NULL) {
3265 if (sib == this) {
3266 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3267 }
3268
3269 guarantee(sib->is_klass(), "should be klass");
3270 guarantee(sib->super() == super, "siblings should have same superklass");
3271 }
3272
3273 // Verify implementor fields
3274 Klass* im = implementor();
3275 if (im != NULL) {
3276 guarantee(is_interface(), "only interfaces should have implementor set");
3277 guarantee(im->is_klass(), "should be klass");
3278 guarantee(!im->is_interface() || im == this,
3279 "implementors cannot be interfaces");
3280 }
3281
3282 // Verify local interfaces
3283 if (local_interfaces()) {
3284 Array<Klass*>* local_interfaces = this->local_interfaces();
3285 for (int j = 0; j < local_interfaces->length(); j++) {
3286 Klass* e = local_interfaces->at(j);
3287 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3288 }
3289 }
3290
3291 // Verify transitive interfaces
3292 if (transitive_interfaces() != NULL) {
3293 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3294 for (int j = 0; j < transitive_interfaces->length(); j++) {
3295 Klass* e = transitive_interfaces->at(j);
3296 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3297 }
3298 }
3299
3300 // Verify methods
3301 if (methods() != NULL) {
3302 Array<Method*>* methods = this->methods();
3303 for (int j = 0; j < methods->length(); j++) {
3304 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3305 }
3306 for (int j = 0; j < methods->length() - 1; j++) {
3307 Method* m1 = methods->at(j);
3308 Method* m2 = methods->at(j + 1);
3309 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3310 }
3311 }
3312
3313 // Verify method ordering
3314 if (method_ordering() != NULL) {
3315 Array<int>* method_ordering = this->method_ordering();
3316 int length = method_ordering->length();
3317 if (JvmtiExport::can_maintain_original_method_order() ||
3318 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3319 guarantee(length == methods()->length(), "invalid method ordering length");
3320 jlong sum = 0;
3321 for (int j = 0; j < length; j++) {
3322 int original_index = method_ordering->at(j);
3323 guarantee(original_index >= 0, "invalid method ordering index");
3324 guarantee(original_index < length, "invalid method ordering index");
3325 sum += original_index;
3326 }
3327 // Verify sum of indices 0,1,...,length-1
3328 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3329 } else {
3330 guarantee(length == 0, "invalid method ordering length");
3331 }
3332 }
3333
3334 // Verify default methods
3335 if (default_methods() != NULL) {
3336 Array<Method*>* methods = this->default_methods();
3337 for (int j = 0; j < methods->length(); j++) {
3338 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3339 }
3340 for (int j = 0; j < methods->length() - 1; j++) {
3341 Method* m1 = methods->at(j);
3342 Method* m2 = methods->at(j + 1);
3343 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3344 }
3345 }
3346
3347 // Verify JNI static field identifiers
3348 if (jni_ids() != NULL) {
3349 jni_ids()->verify(this);
3350 }
3351
3352 // Verify other fields
3353 if (array_klasses() != NULL) {
3354 guarantee(array_klasses()->is_klass(), "should be klass");
3355 }
3356 if (constants() != NULL) {
3357 guarantee(constants()->is_constantPool(), "should be constant pool");
3358 }
3359 const Klass* host = host_klass();
3360 if (host != NULL) {
3361 guarantee(host->is_klass(), "should be klass");
3362 }
3363 }
3364
3365 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3366 Klass::oop_verify_on(obj, st);
3367 VerifyFieldClosure blk;
3368 obj->oop_iterate_no_header(&blk);
3369 }
3370
3371
3372 // JNIid class for jfieldIDs only
3373 // Note to reviewers:
3374 // These JNI functions are just moved over to column 1 and not changed
3375 // in the compressed oops workspace.
3376 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3377 _holder = holder;
3378 _offset = offset;
3379 _next = next;
3380 debug_only(_is_static_field_id = false;)
3381 }
3382
3383
3384 JNIid* JNIid::find(int offset) {
3385 JNIid* current = this;
3386 while (current != NULL) {
3387 if (current->offset() == offset) return current;
3388 current = current->next();
3389 }
3390 return NULL;
3391 }
3392
3393 void JNIid::deallocate(JNIid* current) {
3394 while (current != NULL) {
3395 JNIid* next = current->next();
3396 delete current;
3397 current = next;
3398 }
3399 }
3400
3401
3402 void JNIid::verify(Klass* holder) {
3403 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3404 int end_field_offset;
3405 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3406
3407 JNIid* current = this;
3408 while (current != NULL) {
3409 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3410 #ifdef ASSERT
3411 int o = current->offset();
3412 if (current->is_static_field_id()) {
3413 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3414 }
3415 #endif
3416 current = current->next();
3417 }
3418 }
3419
3420
3421 #ifdef ASSERT
3422 void InstanceKlass::set_init_state(ClassState state) {
3423 bool good_state = is_shared() ? (_init_state <= state)
3424 : (_init_state < state);
3425 assert(good_state || state == allocated, "illegal state transition");
3426 _init_state = (u1)state;
3427 }
3428 #endif
3429
3430 #if INCLUDE_JVMTI
3431
3432 // RedefineClasses() support for previous versions
3433
3434 // Globally, there is at least one previous version of a class to walk
3435 // during class unloading, which is saved because old methods in the class
3436 // are still running. Otherwise the previous version list is cleaned up.
3437 bool InstanceKlass::_has_previous_versions = false;
3438
3439 // Returns true if there are previous versions of a class for class
3440 // unloading only. Also resets the flag to false. purge_previous_version
3441 // will set the flag to true if there are any left, i.e., if there's any
3442 // work to do for next time. This is to avoid the expensive code cache
3443 // walk in CLDG::do_unloading().
3444 bool InstanceKlass::has_previous_versions_and_reset() {
3445 bool ret = _has_previous_versions;
3446 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3447 ret ? "true" : "false");
3448 _has_previous_versions = false;
3449 return ret;
3450 }
3451
3452 // Purge previous versions before adding new previous versions of the class and
3453 // during class unloading.
3454 void InstanceKlass::purge_previous_version_list() {
3455 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3456 assert(has_been_redefined(), "Should only be called for main class");
3457
3458 // Quick exit.
3459 if (previous_versions() == NULL) {
3460 return;
3461 }
3462
3463 // This klass has previous versions so see what we can cleanup
3464 // while it is safe to do so.
3465
3466 int deleted_count = 0; // leave debugging breadcrumbs
3467 int live_count = 0;
3468 ClassLoaderData* loader_data = class_loader_data();
3469 assert(loader_data != NULL, "should never be null");
3470
3471 ResourceMark rm;
3472 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3473
3474 // previous versions are linked together through the InstanceKlass
3475 InstanceKlass* pv_node = previous_versions();
3476 InstanceKlass* last = this;
3477 int version = 0;
3478
3479 // check the previous versions list
3480 for (; pv_node != NULL; ) {
3481
3482 ConstantPool* pvcp = pv_node->constants();
3483 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3484
3485 if (!pvcp->on_stack()) {
3486 // If the constant pool isn't on stack, none of the methods
3487 // are executing. Unlink this previous_version.
3488 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3489 // so will be deallocated during the next phase of class unloading.
3490 log_trace(redefine, class, iklass, purge)
3491 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3492 // For debugging purposes.
3493 pv_node->set_is_scratch_class();
3494 // Unlink from previous version list.
3495 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3496 InstanceKlass* next = pv_node->previous_versions();
3497 pv_node->link_previous_versions(NULL); // point next to NULL
3498 last->link_previous_versions(next);
3499 // Add to the deallocate list after unlinking
3500 loader_data->add_to_deallocate_list(pv_node);
3501 pv_node = next;
3502 deleted_count++;
3503 version++;
3504 continue;
3505 } else {
3506 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3507 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3508 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3509 live_count++;
3510 // found a previous version for next time we do class unloading
3511 _has_previous_versions = true;
3512 }
3513
3514 // At least one method is live in this previous version.
3515 // Reset dead EMCP methods not to get breakpoints.
3516 // All methods are deallocated when all of the methods for this class are no
3517 // longer running.
3518 Array<Method*>* method_refs = pv_node->methods();
3519 if (method_refs != NULL) {
3520 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3521 for (int j = 0; j < method_refs->length(); j++) {
3522 Method* method = method_refs->at(j);
3523
3524 if (!method->on_stack()) {
3525 // no breakpoints for non-running methods
3526 if (method->is_running_emcp()) {
3527 method->set_running_emcp(false);
3528 }
3529 } else {
3530 assert (method->is_obsolete() || method->is_running_emcp(),
3531 "emcp method cannot run after emcp bit is cleared");
3532 log_trace(redefine, class, iklass, purge)
3533 ("purge: %s(%s): prev method @%d in version @%d is alive",
3534 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3535 }
3536 }
3537 }
3538 // next previous version
3539 last = pv_node;
3540 pv_node = pv_node->previous_versions();
3541 version++;
3542 }
3543 log_trace(redefine, class, iklass, purge)
3544 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3545 }
3546
3547 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3548 int emcp_method_count) {
3549 int obsolete_method_count = old_methods->length() - emcp_method_count;
3550
3551 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3552 _previous_versions != NULL) {
3553 // We have a mix of obsolete and EMCP methods so we have to
3554 // clear out any matching EMCP method entries the hard way.
3555 int local_count = 0;
3556 for (int i = 0; i < old_methods->length(); i++) {
3557 Method* old_method = old_methods->at(i);
3558 if (old_method->is_obsolete()) {
3559 // only obsolete methods are interesting
3560 Symbol* m_name = old_method->name();
3561 Symbol* m_signature = old_method->signature();
3562
3563 // previous versions are linked together through the InstanceKlass
3564 int j = 0;
3565 for (InstanceKlass* prev_version = _previous_versions;
3566 prev_version != NULL;
3567 prev_version = prev_version->previous_versions(), j++) {
3568
3569 Array<Method*>* method_refs = prev_version->methods();
3570 for (int k = 0; k < method_refs->length(); k++) {
3571 Method* method = method_refs->at(k);
3572
3573 if (!method->is_obsolete() &&
3574 method->name() == m_name &&
3575 method->signature() == m_signature) {
3576 // The current RedefineClasses() call has made all EMCP
3577 // versions of this method obsolete so mark it as obsolete
3578 log_trace(redefine, class, iklass, add)
3579 ("%s(%s): flush obsolete method @%d in version @%d",
3580 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3581
3582 method->set_is_obsolete();
3583 break;
3584 }
3585 }
3586
3587 // The previous loop may not find a matching EMCP method, but
3588 // that doesn't mean that we can optimize and not go any
3589 // further back in the PreviousVersion generations. The EMCP
3590 // method for this generation could have already been made obsolete,
3591 // but there still may be an older EMCP method that has not
3592 // been made obsolete.
3593 }
3594
3595 if (++local_count >= obsolete_method_count) {
3596 // no more obsolete methods so bail out now
3597 break;
3598 }
3599 }
3600 }
3601 }
3602 }
3603
3604 // Save the scratch_class as the previous version if any of the methods are running.
3605 // The previous_versions are used to set breakpoints in EMCP methods and they are
3606 // also used to clean MethodData links to redefined methods that are no longer running.
3607 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3608 int emcp_method_count) {
3609 assert(Thread::current()->is_VM_thread(),
3610 "only VMThread can add previous versions");
3611
3612 ResourceMark rm;
3613 log_trace(redefine, class, iklass, add)
3614 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3615
3616 // Clean out old previous versions for this class
3617 purge_previous_version_list();
3618
3619 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3620 // a previous redefinition may be made obsolete by this redefinition.
3621 Array<Method*>* old_methods = scratch_class->methods();
3622 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3623
3624 // If the constant pool for this previous version of the class
3625 // is not marked as being on the stack, then none of the methods
3626 // in this previous version of the class are on the stack so
3627 // we don't need to add this as a previous version.
3628 ConstantPool* cp_ref = scratch_class->constants();
3629 if (!cp_ref->on_stack()) {
3630 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3631 // For debugging purposes.
3632 scratch_class->set_is_scratch_class();
3633 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3634 return;
3635 }
3636
3637 if (emcp_method_count != 0) {
3638 // At least one method is still running, check for EMCP methods
3639 for (int i = 0; i < old_methods->length(); i++) {
3640 Method* old_method = old_methods->at(i);
3641 if (!old_method->is_obsolete() && old_method->on_stack()) {
3642 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3643 // we can add breakpoints for it.
3644
3645 // We set the method->on_stack bit during safepoints for class redefinition
3646 // and use this bit to set the is_running_emcp bit.
3647 // After the safepoint, the on_stack bit is cleared and the running emcp
3648 // method may exit. If so, we would set a breakpoint in a method that
3649 // is never reached, but this won't be noticeable to the programmer.
3650 old_method->set_running_emcp(true);
3651 log_trace(redefine, class, iklass, add)
3652 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3653 } else if (!old_method->is_obsolete()) {
3654 log_trace(redefine, class, iklass, add)
3655 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3656 }
3657 }
3658 }
3659
3660 // Add previous version if any methods are still running.
3661 // Set has_previous_version flag for processing during class unloading.
3662 _has_previous_versions = true;
3663 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3664 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3665 scratch_class->link_previous_versions(previous_versions());
3666 link_previous_versions(scratch_class);
3667 } // end add_previous_version()
3668
3669 #endif // INCLUDE_JVMTI
3670
3671 Method* InstanceKlass::method_with_idnum(int idnum) {
3672 Method* m = NULL;
3673 if (idnum < methods()->length()) {
3674 m = methods()->at(idnum);
3675 }
3676 if (m == NULL || m->method_idnum() != idnum) {
3677 for (int index = 0; index < methods()->length(); ++index) {
3678 m = methods()->at(index);
3679 if (m->method_idnum() == idnum) {
3680 return m;
3681 }
3682 }
3683 // None found, return null for the caller to handle.
3684 return NULL;
3685 }
3686 return m;
3687 }
3688
3689
3690 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3691 if (idnum >= methods()->length()) {
3692 return NULL;
3693 }
3694 Method* m = methods()->at(idnum);
3695 if (m != NULL && m->orig_method_idnum() == idnum) {
3696 return m;
3697 }
3698 // Obsolete method idnum does not match the original idnum
3699 for (int index = 0; index < methods()->length(); ++index) {
3700 m = methods()->at(index);
3701 if (m->orig_method_idnum() == idnum) {
3702 return m;
3703 }
3704 }
3705 // None found, return null for the caller to handle.
3706 return NULL;
3707 }
3708
3709
3710 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3711 InstanceKlass* holder = get_klass_version(version);
3712 if (holder == NULL) {
3713 return NULL; // The version of klass is gone, no method is found
3714 }
3715 Method* method = holder->method_with_orig_idnum(idnum);
3716 return method;
3717 }
3718
3719 #if INCLUDE_JVMTI
3720 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3721 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) {
3722 // Ignore the archived class stream data
3723 return NULL;
3724 } else {
3725 return _cached_class_file;
3726 }
3727 }
3728
3729 jint InstanceKlass::get_cached_class_file_len() {
3730 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3731 }
3732
3733 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3734 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3735 }
3736
3737 #if INCLUDE_CDS
3738 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3739 if (DumpSharedSpaces) {
3740 return _cached_class_file;
3741 } else {
3742 assert(this->is_shared(), "class should be shared");
3743 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) {
3744 return _cached_class_file;
3745 } else {
3746 return NULL;
3747 }
3748 }
3749 }
3750 #endif
3751 #endif