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 "classfile/dictionary.hpp"
27 #include "classfile/javaClasses.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "gc/shared/collectedHeap.inline.hpp"
31 #include "logging/log.hpp"
32 #include "memory/heapInspection.hpp"
33 #include "memory/metadataFactory.hpp"
34 #include "memory/metaspaceClosure.hpp"
35 #include "memory/metaspaceShared.hpp"
36 #include "memory/oopFactory.hpp"
37 #include "memory/resourceArea.hpp"
38 #include "oops/access.inline.hpp"
39 #include "oops/instanceKlass.hpp"
40 #include "oops/klass.inline.hpp"
41 #include "oops/oop.inline.hpp"
42 #include "runtime/atomic.hpp"
43 #include "runtime/orderAccess.inline.hpp"
44 #include "trace/traceMacros.hpp"
45 #include "utilities/macros.hpp"
46 #include "utilities/stack.inline.hpp"
47
48 void Klass::set_java_mirror(Handle m) {
49 assert(!m.is_null(), "New mirror should never be null.");
50 assert(_java_mirror.resolve() == NULL, "should only be used to initialize mirror");
51 _java_mirror = class_loader_data()->add_handle(m);
52 }
53
54 oop Klass::java_mirror() const {
55 return _java_mirror.resolve();
56 }
57
58 oop Klass::java_mirror_phantom() {
59 // Loading the klass_holder as a phantom oop ref keeps the class alive.
60 // After the holder has been kept alive, it is safe to return the mirror.
61 (void)klass_holder_phantom();
62 return java_mirror();
63 }
64
65 oop Klass::klass_holder_phantom() {
66 oop* addr = &class_loader_data()->_class_loader;
67 return RootAccess<IN_CONCURRENT_ROOT | ON_PHANTOM_OOP_REF>::oop_load(addr);
68 }
69
70 bool Klass::is_cloneable() const {
71 return _access_flags.is_cloneable_fast() ||
72 is_subtype_of(SystemDictionary::Cloneable_klass());
73 }
74
75 void Klass::set_is_cloneable() {
76 if (name() != vmSymbols::java_lang_invoke_MemberName()) {
77 _access_flags.set_is_cloneable_fast();
78 } else {
79 assert(is_final(), "no subclasses allowed");
80 // MemberName cloning should not be intrinsified and always happen in JVM_Clone.
81 }
82 }
83
84 void Klass::set_name(Symbol* n) {
85 _name = n;
86 if (_name != NULL) _name->increment_refcount();
87 }
88
89 bool Klass::is_subclass_of(const Klass* k) const {
90 // Run up the super chain and check
91 if (this == k) return true;
92
93 Klass* t = const_cast<Klass*>(this)->super();
94
95 while (t != NULL) {
96 if (t == k) return true;
97 t = t->super();
98 }
99 return false;
100 }
101
102 bool Klass::search_secondary_supers(Klass* k) const {
103 // Put some extra logic here out-of-line, before the search proper.
104 // This cuts down the size of the inline method.
105
106 // This is necessary, since I am never in my own secondary_super list.
107 if (this == k)
108 return true;
109 // Scan the array-of-objects for a match
110 int cnt = secondary_supers()->length();
111 for (int i = 0; i < cnt; i++) {
112 if (secondary_supers()->at(i) == k) {
113 ((Klass*)this)->set_secondary_super_cache(k);
114 return true;
115 }
116 }
117 return false;
118 }
119
120 // Return self, except for abstract classes with exactly 1
121 // implementor. Then return the 1 concrete implementation.
122 Klass *Klass::up_cast_abstract() {
123 Klass *r = this;
124 while( r->is_abstract() ) { // Receiver is abstract?
125 Klass *s = r->subklass(); // Check for exactly 1 subklass
126 if( !s || s->next_sibling() ) // Oops; wrong count; give up
127 return this; // Return 'this' as a no-progress flag
128 r = s; // Loop till find concrete class
129 }
130 return r; // Return the 1 concrete class
131 }
132
133 // Find LCA in class hierarchy
134 Klass *Klass::LCA( Klass *k2 ) {
135 Klass *k1 = this;
136 while( 1 ) {
137 if( k1->is_subtype_of(k2) ) return k2;
138 if( k2->is_subtype_of(k1) ) return k1;
139 k1 = k1->super();
140 k2 = k2->super();
141 }
142 }
143
144
145 void Klass::check_valid_for_instantiation(bool throwError, TRAPS) {
146 ResourceMark rm(THREAD);
147 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
148 : vmSymbols::java_lang_InstantiationException(), external_name());
149 }
150
151
152 void Klass::copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS) {
153 THROW(vmSymbols::java_lang_ArrayStoreException());
154 }
155
156
157 void Klass::initialize(TRAPS) {
158 ShouldNotReachHere();
159 }
160
161 bool Klass::compute_is_subtype_of(Klass* k) {
162 assert(k->is_klass(), "argument must be a class");
163 return is_subclass_of(k);
164 }
165
166 Klass* Klass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
167 #ifdef ASSERT
168 tty->print_cr("Error: find_field called on a klass oop."
169 " Likely error: reflection method does not correctly"
170 " wrap return value in a mirror object.");
171 #endif
172 ShouldNotReachHere();
173 return NULL;
174 }
175
176 Method* Klass::uncached_lookup_method(const Symbol* name, const Symbol* signature, OverpassLookupMode overpass_mode) const {
177 #ifdef ASSERT
178 tty->print_cr("Error: uncached_lookup_method called on a klass oop."
179 " Likely error: reflection method does not correctly"
180 " wrap return value in a mirror object.");
181 #endif
182 ShouldNotReachHere();
183 return NULL;
184 }
185
186 void* Klass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS) throw() {
187 return Metaspace::allocate(loader_data, word_size, MetaspaceObj::ClassType, THREAD);
188 }
189
190 // "Normal" instantiation is preceeded by a MetaspaceObj allocation
191 // which zeros out memory - calloc equivalent.
192 // The constructor is also used from CppVtableCloner,
193 // which doesn't zero out the memory before calling the constructor.
194 // Need to set the _java_mirror field explicitly to not hit an assert that the field
195 // should be NULL before setting it.
196 Klass::Klass() : _prototype_header(markOopDesc::prototype()),
197 _shared_class_path_index(-1),
198 _java_mirror(NULL) {
199
200 _primary_supers[0] = this;
201 set_super_check_offset(in_bytes(primary_supers_offset()));
202 }
203
204 jint Klass::array_layout_helper(BasicType etype) {
205 assert(etype >= T_BOOLEAN && etype <= T_OBJECT, "valid etype");
206 // Note that T_ARRAY is not allowed here.
207 int hsize = arrayOopDesc::base_offset_in_bytes(etype);
208 int esize = type2aelembytes(etype);
209 bool isobj = (etype == T_OBJECT);
210 int tag = isobj ? _lh_array_tag_obj_value : _lh_array_tag_type_value;
211 int lh = array_layout_helper(tag, hsize, etype, exact_log2(esize));
212
213 assert(lh < (int)_lh_neutral_value, "must look like an array layout");
214 assert(layout_helper_is_array(lh), "correct kind");
215 assert(layout_helper_is_objArray(lh) == isobj, "correct kind");
216 assert(layout_helper_is_typeArray(lh) == !isobj, "correct kind");
217 assert(layout_helper_header_size(lh) == hsize, "correct decode");
218 assert(layout_helper_element_type(lh) == etype, "correct decode");
219 assert(1 << layout_helper_log2_element_size(lh) == esize, "correct decode");
220
221 return lh;
222 }
223
224 bool Klass::can_be_primary_super_slow() const {
225 if (super() == NULL)
226 return true;
227 else if (super()->super_depth() >= primary_super_limit()-1)
228 return false;
229 else
230 return true;
231 }
232
233 void Klass::initialize_supers(Klass* k, TRAPS) {
234 if (FastSuperclassLimit == 0) {
235 // None of the other machinery matters.
236 set_super(k);
237 return;
238 }
239 if (k == NULL) {
240 set_super(NULL);
241 _primary_supers[0] = this;
242 assert(super_depth() == 0, "Object must already be initialized properly");
243 } else if (k != super() || k == SystemDictionary::Object_klass()) {
244 assert(super() == NULL || super() == SystemDictionary::Object_klass(),
245 "initialize this only once to a non-trivial value");
246 set_super(k);
247 Klass* sup = k;
248 int sup_depth = sup->super_depth();
249 juint my_depth = MIN2(sup_depth + 1, (int)primary_super_limit());
250 if (!can_be_primary_super_slow())
251 my_depth = primary_super_limit();
252 for (juint i = 0; i < my_depth; i++) {
253 _primary_supers[i] = sup->_primary_supers[i];
254 }
255 Klass* *super_check_cell;
256 if (my_depth < primary_super_limit()) {
257 _primary_supers[my_depth] = this;
258 super_check_cell = &_primary_supers[my_depth];
259 } else {
260 // Overflow of the primary_supers array forces me to be secondary.
261 super_check_cell = &_secondary_super_cache;
262 }
263 set_super_check_offset((address)super_check_cell - (address) this);
264
265 #ifdef ASSERT
266 {
267 juint j = super_depth();
268 assert(j == my_depth, "computed accessor gets right answer");
269 Klass* t = this;
270 while (!t->can_be_primary_super()) {
271 t = t->super();
272 j = t->super_depth();
273 }
274 for (juint j1 = j+1; j1 < primary_super_limit(); j1++) {
275 assert(primary_super_of_depth(j1) == NULL, "super list padding");
276 }
277 while (t != NULL) {
278 assert(primary_super_of_depth(j) == t, "super list initialization");
279 t = t->super();
280 --j;
281 }
282 assert(j == (juint)-1, "correct depth count");
283 }
284 #endif
285 }
286
287 if (secondary_supers() == NULL) {
288
289 // Now compute the list of secondary supertypes.
290 // Secondaries can occasionally be on the super chain,
291 // if the inline "_primary_supers" array overflows.
292 int extras = 0;
293 Klass* p;
294 for (p = super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
295 ++extras;
296 }
297
298 ResourceMark rm(THREAD); // need to reclaim GrowableArrays allocated below
299
300 // Compute the "real" non-extra secondaries.
301 GrowableArray<Klass*>* secondaries = compute_secondary_supers(extras);
302 if (secondaries == NULL) {
303 // secondary_supers set by compute_secondary_supers
304 return;
305 }
306
307 GrowableArray<Klass*>* primaries = new GrowableArray<Klass*>(extras);
308
309 for (p = super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
310 int i; // Scan for overflow primaries being duplicates of 2nd'arys
311
312 // This happens frequently for very deeply nested arrays: the
313 // primary superclass chain overflows into the secondary. The
314 // secondary list contains the element_klass's secondaries with
315 // an extra array dimension added. If the element_klass's
316 // secondary list already contains some primary overflows, they
317 // (with the extra level of array-ness) will collide with the
318 // normal primary superclass overflows.
319 for( i = 0; i < secondaries->length(); i++ ) {
320 if( secondaries->at(i) == p )
321 break;
322 }
323 if( i < secondaries->length() )
324 continue; // It's a dup, don't put it in
325 primaries->push(p);
326 }
327 // Combine the two arrays into a metadata object to pack the array.
328 // The primaries are added in the reverse order, then the secondaries.
329 int new_length = primaries->length() + secondaries->length();
330 Array<Klass*>* s2 = MetadataFactory::new_array<Klass*>(
331 class_loader_data(), new_length, CHECK);
332 int fill_p = primaries->length();
333 for (int j = 0; j < fill_p; j++) {
334 s2->at_put(j, primaries->pop()); // add primaries in reverse order.
335 }
336 for( int j = 0; j < secondaries->length(); j++ ) {
337 s2->at_put(j+fill_p, secondaries->at(j)); // add secondaries on the end.
338 }
339
340 #ifdef ASSERT
341 // We must not copy any NULL placeholders left over from bootstrap.
342 for (int j = 0; j < s2->length(); j++) {
343 assert(s2->at(j) != NULL, "correct bootstrapping order");
344 }
345 #endif
346
347 set_secondary_supers(s2);
348 }
349 }
350
351 GrowableArray<Klass*>* Klass::compute_secondary_supers(int num_extra_slots) {
352 assert(num_extra_slots == 0, "override for complex klasses");
353 set_secondary_supers(Universe::the_empty_klass_array());
354 return NULL;
355 }
356
357
358 InstanceKlass* Klass::superklass() const {
359 assert(super() == NULL || super()->is_instance_klass(), "must be instance klass");
360 return _super == NULL ? NULL : InstanceKlass::cast(_super);
361 }
362
363 void Klass::set_subklass(Klass* s) {
364 assert(s != this, "sanity check");
365 _subklass = s;
366 }
367
368 void Klass::set_next_sibling(Klass* s) {
369 assert(s != this, "sanity check");
370 _next_sibling = s;
371 }
372
373 void Klass::append_to_sibling_list() {
374 debug_only(verify();)
375 // add ourselves to superklass' subklass list
376 InstanceKlass* super = superklass();
377 if (super == NULL) return; // special case: class Object
378 assert((!super->is_interface() // interfaces cannot be supers
379 && (super->superklass() == NULL || !is_interface())),
380 "an interface can only be a subklass of Object");
381 Klass* prev_first_subklass = super->subklass();
382 if (prev_first_subklass != NULL) {
383 // set our sibling to be the superklass' previous first subklass
384 set_next_sibling(prev_first_subklass);
385 }
386 // make ourselves the superklass' first subklass
387 super->set_subklass(this);
388 debug_only(verify();)
389 }
390
391 bool Klass::is_loader_alive(BoolObjectClosure* is_alive) {
392 #ifdef ASSERT
393 // The class is alive iff the class loader is alive.
394 oop loader = class_loader();
395 bool loader_alive = (loader == NULL) || is_alive->do_object_b(loader);
396 #endif // ASSERT
397
398 // The class is alive if it's mirror is alive (which should be marked if the
399 // loader is alive) unless it's an anoymous class.
400 bool mirror_alive = is_alive->do_object_b(java_mirror());
401 assert(!mirror_alive || loader_alive, "loader must be alive if the mirror is"
402 " but not the other way around with anonymous classes");
403 return mirror_alive;
404 }
405
406 void Klass::clean_weak_klass_links(BoolObjectClosure* is_alive, bool clean_alive_klasses) {
407 if (!ClassUnloading) {
408 return;
409 }
410
411 Klass* root = SystemDictionary::Object_klass();
412 Stack<Klass*, mtGC> stack;
413
414 stack.push(root);
415 while (!stack.is_empty()) {
416 Klass* current = stack.pop();
417
418 assert(current->is_loader_alive(is_alive), "just checking, this should be live");
419
420 // Find and set the first alive subklass
421 Klass* sub = current->subklass();
422 while (sub != NULL && !sub->is_loader_alive(is_alive)) {
423 #ifndef PRODUCT
424 if (log_is_enabled(Trace, class, unload)) {
425 ResourceMark rm;
426 log_trace(class, unload)("unlinking class (subclass): %s", sub->external_name());
427 }
428 #endif
429 sub = sub->next_sibling();
430 }
431 current->set_subklass(sub);
432 if (sub != NULL) {
433 stack.push(sub);
434 }
435
436 // Find and set the first alive sibling
437 Klass* sibling = current->next_sibling();
438 while (sibling != NULL && !sibling->is_loader_alive(is_alive)) {
439 if (log_is_enabled(Trace, class, unload)) {
440 ResourceMark rm;
441 log_trace(class, unload)("[Unlinking class (sibling) %s]", sibling->external_name());
442 }
443 sibling = sibling->next_sibling();
444 }
445 current->set_next_sibling(sibling);
446 if (sibling != NULL) {
447 stack.push(sibling);
448 }
449
450 // Clean the implementors list and method data.
451 if (clean_alive_klasses && current->is_instance_klass()) {
452 InstanceKlass* ik = InstanceKlass::cast(current);
453 ik->clean_weak_instanceklass_links(is_alive);
454
455 // JVMTI RedefineClasses creates previous versions that are not in
456 // the class hierarchy, so process them here.
457 while ((ik = ik->previous_versions()) != NULL) {
458 ik->clean_weak_instanceklass_links(is_alive);
459 }
460 }
461 }
462 }
463
464 void Klass::metaspace_pointers_do(MetaspaceClosure* it) {
465 if (log_is_enabled(Trace, cds)) {
466 ResourceMark rm;
467 log_trace(cds)("Iter(Klass): %p (%s)", this, external_name());
468 }
469
470 it->push(&_name);
471 it->push(&_secondary_super_cache);
472 it->push(&_secondary_supers);
473 for (int i = 0; i < _primary_super_limit; i++) {
474 it->push(&_primary_supers[i]);
475 }
476 it->push(&_super);
477 it->push(&_subklass);
478 it->push(&_next_sibling);
479 it->push(&_next_link);
480
481 vtableEntry* vt = start_of_vtable();
482 for (int i=0; i<vtable_length(); i++) {
483 it->push(vt[i].method_addr());
484 }
485 }
486
487 void Klass::remove_unshareable_info() {
488 assert (DumpSharedSpaces, "only called for DumpSharedSpaces");
489 TRACE_REMOVE_ID(this);
490 if (log_is_enabled(Trace, cds, unshareable)) {
491 ResourceMark rm;
492 log_trace(cds, unshareable)("remove: %s", external_name());
493 }
494
495 set_subklass(NULL);
496 set_next_sibling(NULL);
497 set_next_link(NULL);
498
499 // Null out class_loader_data because we don't share that yet.
500 set_class_loader_data(NULL);
501 set_is_shared();
502 }
503
504 void Klass::remove_java_mirror() {
505 assert (DumpSharedSpaces, "only called for DumpSharedSpaces");
506 if (log_is_enabled(Trace, cds, unshareable)) {
507 ResourceMark rm;
508 log_trace(cds, unshareable)("remove java_mirror: %s", external_name());
509 }
510 // Just null out the mirror. The class_loader_data() no longer exists.
511 _java_mirror = NULL;
512 }
513
514 void Klass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
515 assert(is_klass(), "ensure C++ vtable is restored");
516 assert(is_shared(), "must be set");
517 TRACE_RESTORE_ID(this);
518 if (log_is_enabled(Trace, cds, unshareable)) {
519 ResourceMark rm;
520 log_trace(cds, unshareable)("restore: %s", external_name());
521 }
522
523 // If an exception happened during CDS restore, some of these fields may already be
524 // set. We leave the class on the CLD list, even if incomplete so that we don't
525 // modify the CLD list outside a safepoint.
526 if (class_loader_data() == NULL) {
527 // Restore class_loader_data to the null class loader data
528 set_class_loader_data(loader_data);
529
530 // Add to null class loader list first before creating the mirror
531 // (same order as class file parsing)
532 loader_data->add_class(this);
533 }
534
535 // Recreate the class mirror.
536 // Only recreate it if not present. A previous attempt to restore may have
537 // gotten an OOM later but keep the mirror if it was created.
538 if (java_mirror() == NULL) {
539 Handle loader(THREAD, loader_data->class_loader());
540 ModuleEntry* module_entry = NULL;
541 Klass* k = this;
542 if (k->is_objArray_klass()) {
543 k = ObjArrayKlass::cast(k)->bottom_klass();
544 }
545 // Obtain klass' module.
546 if (k->is_instance_klass()) {
547 InstanceKlass* ik = (InstanceKlass*) k;
548 module_entry = ik->module();
549 } else {
550 module_entry = ModuleEntryTable::javabase_moduleEntry();
551 }
552 // Obtain java.lang.Module, if available
553 Handle module_handle(THREAD, ((module_entry != NULL) ? module_entry->module() : (oop)NULL));
554 java_lang_Class::create_mirror(this, loader, module_handle, protection_domain, CHECK);
555 }
556 }
557
558 Klass* Klass::array_klass_or_null(int rank) {
559 EXCEPTION_MARK;
560 // No exception can be thrown by array_klass_impl when called with or_null == true.
561 // (In anycase, the execption mark will fail if it do so)
562 return array_klass_impl(true, rank, THREAD);
563 }
564
565
566 Klass* Klass::array_klass_or_null() {
567 EXCEPTION_MARK;
568 // No exception can be thrown by array_klass_impl when called with or_null == true.
569 // (In anycase, the execption mark will fail if it do so)
570 return array_klass_impl(true, THREAD);
571 }
572
573
574 Klass* Klass::array_klass_impl(bool or_null, int rank, TRAPS) {
575 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
576 return NULL;
577 }
578
579
580 Klass* Klass::array_klass_impl(bool or_null, TRAPS) {
581 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
582 return NULL;
583 }
584
585 oop Klass::class_loader() const { return class_loader_data()->class_loader(); }
586
587 // In product mode, this function doesn't have virtual function calls so
588 // there might be some performance advantage to handling InstanceKlass here.
589 const char* Klass::external_name() const {
590 if (is_instance_klass()) {
591 const InstanceKlass* ik = static_cast<const InstanceKlass*>(this);
592 if (ik->is_anonymous()) {
593 intptr_t hash = 0;
594 if (ik->java_mirror() != NULL) {
595 // java_mirror might not be created yet, return 0 as hash.
596 hash = ik->java_mirror()->identity_hash();
597 }
598 char hash_buf[40];
599 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
600 size_t hash_len = strlen(hash_buf);
601
602 size_t result_len = name()->utf8_length();
603 char* result = NEW_RESOURCE_ARRAY(char, result_len + hash_len + 1);
604 name()->as_klass_external_name(result, (int) result_len + 1);
605 assert(strlen(result) == result_len, "");
606 strcpy(result + result_len, hash_buf);
607 assert(strlen(result) == result_len + hash_len, "");
608 return result;
609 }
610 }
611 if (name() == NULL) return "<unknown>";
612 return name()->as_klass_external_name();
613 }
614
615
616 const char* Klass::signature_name() const {
617 if (name() == NULL) return "<unknown>";
618 return name()->as_C_string();
619 }
620
621 // Unless overridden, modifier_flags is 0.
622 jint Klass::compute_modifier_flags(TRAPS) const {
623 return 0;
624 }
625
626 int Klass::atomic_incr_biased_lock_revocation_count() {
627 return (int) Atomic::add(1, &_biased_lock_revocation_count);
628 }
629
630 // Unless overridden, jvmti_class_status has no flags set.
631 jint Klass::jvmti_class_status() const {
632 return 0;
633 }
634
635
636 // Printing
637
638 void Klass::print_on(outputStream* st) const {
639 ResourceMark rm;
640 // print title
641 st->print("%s", internal_name());
642 print_address_on(st);
643 st->cr();
644 }
645
646 void Klass::oop_print_on(oop obj, outputStream* st) {
647 ResourceMark rm;
648 // print title
649 st->print_cr("%s ", internal_name());
650 obj->print_address_on(st);
651
652 if (WizardMode) {
653 // print header
654 obj->mark()->print_on(st);
655 }
656
657 // print class
658 st->print(" - klass: ");
659 obj->klass()->print_value_on(st);
660 st->cr();
661 }
662
663 void Klass::oop_print_value_on(oop obj, outputStream* st) {
664 // print title
665 ResourceMark rm; // Cannot print in debug mode without this
666 st->print("%s", internal_name());
667 obj->print_address_on(st);
668 }
669
670 #if INCLUDE_SERVICES
671 // Size Statistics
672 void Klass::collect_statistics(KlassSizeStats *sz) const {
673 sz->_klass_bytes = sz->count(this);
674 sz->_mirror_bytes = sz->count(java_mirror());
675 sz->_secondary_supers_bytes = sz->count_array(secondary_supers());
676
677 sz->_ro_bytes += sz->_secondary_supers_bytes;
678 sz->_rw_bytes += sz->_klass_bytes + sz->_mirror_bytes;
679 }
680 #endif // INCLUDE_SERVICES
681
682 // Verification
683
684 void Klass::verify_on(outputStream* st) {
685
686 // This can be expensive, but it is worth checking that this klass is actually
687 // in the CLD graph but not in production.
688 assert(Metaspace::contains((address)this), "Should be");
689
690 guarantee(this->is_klass(),"should be klass");
691
692 if (super() != NULL) {
693 guarantee(super()->is_klass(), "should be klass");
694 }
695 if (secondary_super_cache() != NULL) {
696 Klass* ko = secondary_super_cache();
697 guarantee(ko->is_klass(), "should be klass");
698 }
699 for ( uint i = 0; i < primary_super_limit(); i++ ) {
700 Klass* ko = _primary_supers[i];
701 if (ko != NULL) {
702 guarantee(ko->is_klass(), "should be klass");
703 }
704 }
705
706 if (java_mirror() != NULL) {
707 guarantee(oopDesc::is_oop(java_mirror()), "should be instance");
708 }
709 }
710
711 void Klass::oop_verify_on(oop obj, outputStream* st) {
712 guarantee(oopDesc::is_oop(obj), "should be oop");
713 guarantee(obj->klass()->is_klass(), "klass field is not a klass");
714 }
715
716 klassVtable Klass::vtable() const {
717 return klassVtable(const_cast<Klass*>(this), start_of_vtable(), vtable_length() / vtableEntry::size());
718 }
719
720 vtableEntry* Klass::start_of_vtable() const {
721 return (vtableEntry*) ((address)this + in_bytes(vtable_start_offset()));
722 }
723
724 Method* Klass::method_at_vtable(int index) {
725 #ifndef PRODUCT
726 assert(index >= 0, "valid vtable index");
727 if (DebugVtables) {
728 verify_vtable_index(index);
729 }
730 #endif
731 return start_of_vtable()[index].method();
732 }
733
734 ByteSize Klass::vtable_start_offset() {
735 return in_ByteSize(InstanceKlass::header_size() * wordSize);
736 }
737
738 #ifndef PRODUCT
739
740 bool Klass::verify_vtable_index(int i) {
741 int limit = vtable_length()/vtableEntry::size();
742 assert(i >= 0 && i < limit, "index %d out of bounds %d", i, limit);
743 return true;
744 }
745
746 bool Klass::verify_itable_index(int i) {
747 assert(is_instance_klass(), "");
748 int method_count = klassItable::method_count_for_interface(this);
749 assert(i >= 0 && i < method_count, "index out of bounds");
750 return true;
751 }
752
753 #endif