1 /*
2 * Copyright (c) 1997, 2015, 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 #ifndef SHARE_VM_OOPS_INSTANCEKLASS_HPP
26 #define SHARE_VM_OOPS_INSTANCEKLASS_HPP
27
28 #include "classfile/classLoaderData.hpp"
29 #include "memory/referenceType.hpp"
30 #include "oops/annotations.hpp"
31 #include "oops/constMethod.hpp"
32 #include "oops/fieldInfo.hpp"
33 #include "oops/instanceOop.hpp"
34 #include "oops/klassVtable.hpp"
35 #include "runtime/atomic.hpp"
36 #include "runtime/handles.hpp"
37 #include "runtime/os.hpp"
38 #include "utilities/accessFlags.hpp"
39 #include "utilities/bitMap.inline.hpp"
40 #include "utilities/macros.hpp"
41 #include "trace/traceMacros.hpp"
42
43 // An InstanceKlass is the VM level representation of a Java class.
44 // It contains all information needed for at class at execution runtime.
45
46 // InstanceKlass layout:
47 // [C++ vtbl pointer ] Klass
48 // [subtype cache ] Klass
49 // [instance size ] Klass
50 // [java mirror ] Klass
51 // [super ] Klass
52 // [access_flags ] Klass
53 // [name ] Klass
54 // [first subklass ] Klass
55 // [next sibling ] Klass
56 // [array klasses ]
57 // [methods ]
58 // [local interfaces ]
59 // [transitive interfaces ]
60 // [fields ]
61 // [constants ]
62 // [class loader ]
63 // [source file name ]
64 // [inner classes ]
65 // [static field size ]
66 // [nonstatic field size ]
67 // [static oop fields size ]
68 // [nonstatic oop maps size ]
69 // [has finalize method ]
70 // [deoptimization mark bit ]
71 // [initialization state ]
72 // [initializing thread ]
73 // [Java vtable length ]
74 // [oop map cache (stack maps) ]
75 // [EMBEDDED Java vtable ] size in words = vtable_len
76 // [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
77 // The embedded nonstatic oop-map blocks are short pairs (offset, length)
78 // indicating where oops are located in instances of this klass.
79 // [EMBEDDED implementor of the interface] only exist for interface
80 // [EMBEDDED host klass ] only exist for an anonymous class (JSR 292 enabled)
81
82
83 // forward declaration for class -- see below for definition
84 class SuperTypeClosure;
85 class JNIid;
86 class jniIdMapBase;
87 class BreakpointInfo;
88 class fieldDescriptor;
89 class DepChange;
90 class nmethodBucket;
91 class PreviousVersionNode;
92 class JvmtiCachedClassFieldMap;
93 class MemberNameTable;
94
95 // This is used in iterators below.
96 class FieldClosure: public StackObj {
97 public:
98 virtual void do_field(fieldDescriptor* fd) = 0;
99 };
100
101 #ifndef PRODUCT
102 // Print fields.
103 // If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields.
104 class FieldPrinter: public FieldClosure {
105 oop _obj;
106 outputStream* _st;
107 public:
108 FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {}
109 void do_field(fieldDescriptor* fd);
110 };
111 #endif // !PRODUCT
112
113 // ValueObjs embedded in klass. Describes where oops are located in instances of
114 // this klass.
115 class OopMapBlock VALUE_OBJ_CLASS_SPEC {
116 public:
117 // Byte offset of the first oop mapped by this block.
118 int offset() const { return _offset; }
119 void set_offset(int offset) { _offset = offset; }
120
121 // Number of oops in this block.
122 uint count() const { return _count; }
123 void set_count(uint count) { _count = count; }
124
125 // sizeof(OopMapBlock) in HeapWords.
126 static const int size_in_words() {
127 return align_size_up(int(sizeof(OopMapBlock)), HeapWordSize) >>
128 LogHeapWordSize;
129 }
130
131 private:
132 int _offset;
133 uint _count;
134 };
135
136 struct JvmtiCachedClassFileData;
137
138 class InstanceKlass: public Klass {
139 friend class VMStructs;
140 friend class ClassFileParser;
141 friend class CompileReplay;
142
143 protected:
144 // Constructor
145 InstanceKlass(int vtable_len,
146 int itable_len,
147 int static_field_size,
148 int nonstatic_oop_map_size,
149 ReferenceType rt,
150 AccessFlags access_flags,
151 bool is_anonymous);
152 public:
153 static InstanceKlass* allocate_instance_klass(
154 ClassLoaderData* loader_data,
155 int vtable_len,
156 int itable_len,
157 int static_field_size,
158 int nonstatic_oop_map_size,
159 ReferenceType rt,
160 AccessFlags access_flags,
161 Symbol* name,
162 Klass* super_klass,
163 bool is_anonymous,
164 TRAPS);
165
166 InstanceKlass() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); }
167
168 // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
169 // of the class loading & initialization procedure, and the use of the states.
170 enum ClassState {
171 allocated, // allocated (but not yet linked)
172 loaded, // loaded and inserted in class hierarchy (but not linked yet)
173 linked, // successfully linked/verified (but not initialized yet)
174 being_initialized, // currently running class initializer
175 fully_initialized, // initialized (successfull final state)
176 initialization_error // error happened during initialization
177 };
178
179 static int number_of_instance_classes() { return _total_instanceKlass_count; }
180
181 private:
182 static volatile int _total_instanceKlass_count;
183
184 protected:
185 // Annotations for this class
186 Annotations* _annotations;
187 // Array classes holding elements of this class.
188 Klass* _array_klasses;
189 // Constant pool for this class.
190 ConstantPool* _constants;
191 // The InnerClasses attribute and EnclosingMethod attribute. The
192 // _inner_classes is an array of shorts. If the class has InnerClasses
193 // attribute, then the _inner_classes array begins with 4-tuples of shorts
194 // [inner_class_info_index, outer_class_info_index,
195 // inner_name_index, inner_class_access_flags] for the InnerClasses
196 // attribute. If the EnclosingMethod attribute exists, it occupies the
197 // last two shorts [class_index, method_index] of the array. If only
198 // the InnerClasses attribute exists, the _inner_classes array length is
199 // number_of_inner_classes * 4. If the class has both InnerClasses
200 // and EnclosingMethod attributes the _inner_classes array length is
201 // number_of_inner_classes * 4 + enclosing_method_attribute_size.
202 Array<jushort>* _inner_classes;
203
204 // the source debug extension for this klass, NULL if not specified.
205 // Specified as UTF-8 string without terminating zero byte in the classfile,
206 // it is stored in the instanceklass as a NULL-terminated UTF-8 string
207 char* _source_debug_extension;
208 // Array name derived from this class which needs unreferencing
209 // if this class is unloaded.
210 Symbol* _array_name;
211
212 // Number of heapOopSize words used by non-static fields in this klass
213 // (including inherited fields but after header_size()).
214 int _nonstatic_field_size;
215 int _static_field_size; // number words used by static fields (oop and non-oop) in this klass
216 // Constant pool index to the utf8 entry of the Generic signature,
217 // or 0 if none.
218 u2 _generic_signature_index;
219 // Constant pool index to the utf8 entry for the name of source file
220 // containing this klass, 0 if not specified.
221 u2 _source_file_name_index;
222 u2 _static_oop_field_count;// number of static oop fields in this klass
223 u2 _java_fields_count; // The number of declared Java fields
224 int _nonstatic_oop_map_size;// size in words of nonstatic oop map blocks
225
226 // _is_marked_dependent can be set concurrently, thus cannot be part of the
227 // _misc_flags.
228 bool _is_marked_dependent; // used for marking during flushing and deoptimization
229 bool _has_unloaded_dependent;
230
231 enum {
232 _misc_rewritten = 1 << 0, // methods rewritten.
233 _misc_has_nonstatic_fields = 1 << 1, // for sizing with UseCompressedOops
234 _misc_should_verify_class = 1 << 2, // allow caching of preverification
235 _misc_is_anonymous = 1 << 3, // has embedded _host_klass field
236 _misc_is_contended = 1 << 4, // marked with contended annotation
237 _misc_has_default_methods = 1 << 5, // class/superclass/implemented interfaces has default methods
238 _misc_declares_default_methods = 1 << 6 // directly declares default methods (any access)
239 };
240 u2 _misc_flags;
241 u2 _minor_version; // minor version number of class file
242 u2 _major_version; // major version number of class file
243 Thread* _init_thread; // Pointer to current thread doing initialization (to handle recusive initialization)
244 int _vtable_len; // length of Java vtable (in words)
245 int _itable_len; // length of Java itable (in words)
246 OopMapCache* volatile _oop_map_cache; // OopMapCache for all methods in the klass (allocated lazily)
247 MemberNameTable* _member_names; // Member names
248 JNIid* _jni_ids; // First JNI identifier for static fields in this class
249 jmethodID* _methods_jmethod_ids; // jmethodIDs corresponding to method_idnum, or NULL if none
250 nmethodBucket* _dependencies; // list of dependent nmethods
251 nmethod* _osr_nmethods_head; // Head of list of on-stack replacement nmethods for this class
252 BreakpointInfo* _breakpoints; // bpt lists, managed by Method*
253 // Array of interesting part(s) of the previous version(s) of this
254 // InstanceKlass. See PreviousVersionWalker below.
255 GrowableArray<PreviousVersionNode *>* _previous_versions;
256 // JVMTI fields can be moved to their own structure - see 6315920
257 // JVMTI: cached class file, before retransformable agent modified it in CFLH
258 JvmtiCachedClassFileData* _cached_class_file;
259
260 volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change
261
262 // Class states are defined as ClassState (see above).
263 // Place the _init_state here to utilize the unused 2-byte after
264 // _idnum_allocated_count.
265 u1 _init_state; // state of class
266 u1 _reference_type; // reference type
267
268 JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration
269
270 NOT_PRODUCT(int _verify_count;) // to avoid redundant verifies
271
272 // Method array.
273 Array<Method*>* _methods;
274 // Default Method Array, concrete methods inherited from interfaces
275 Array<Method*>* _default_methods;
276 // Interface (Klass*s) this class declares locally to implement.
277 Array<Klass*>* _local_interfaces;
278 // Interface (Klass*s) this class implements transitively.
279 Array<Klass*>* _transitive_interfaces;
280 // Int array containing the original order of method in the class file (for JVMTI).
281 Array<int>* _method_ordering;
282 // Int array containing the vtable_indices for default_methods
283 // offset matches _default_methods offset
284 Array<int>* _default_vtable_indices;
285
286 // Instance and static variable information, starts with 6-tuples of shorts
287 // [access, name index, sig index, initval index, low_offset, high_offset]
288 // for all fields, followed by the generic signature data at the end of
289 // the array. Only fields with generic signature attributes have the generic
290 // signature data set in the array. The fields array looks like following:
291 //
292 // f1: [access, name index, sig index, initial value index, low_offset, high_offset]
293 // f2: [access, name index, sig index, initial value index, low_offset, high_offset]
294 // ...
295 // fn: [access, name index, sig index, initial value index, low_offset, high_offset]
296 // [generic signature index]
297 // [generic signature index]
298 // ...
299 Array<u2>* _fields;
300
301 // embedded Java vtable follows here
302 // embedded Java itables follows here
303 // embedded static fields follows here
304 // embedded nonstatic oop-map blocks follows here
305 // embedded implementor of this interface follows here
306 // The embedded implementor only exists if the current klass is an
307 // iterface. The possible values of the implementor fall into following
308 // three cases:
309 // NULL: no implementor.
310 // A Klass* that's not itself: one implementor.
311 // Itself: more than one implementors.
312 // embedded host klass follows here
313 // The embedded host klass only exists in an anonymous class for
314 // dynamic language support (JSR 292 enabled). The host class grants
315 // its access privileges to this class also. The host class is either
316 // named, or a previously loaded anonymous class. A non-anonymous class
317 // or an anonymous class loaded through normal classloading does not
318 // have this embedded field.
319 //
320
321 friend class SystemDictionary;
322
323 public:
324 bool has_nonstatic_fields() const {
325 return (_misc_flags & _misc_has_nonstatic_fields) != 0;
326 }
327 void set_has_nonstatic_fields(bool b) {
328 if (b) {
329 _misc_flags |= _misc_has_nonstatic_fields;
330 } else {
331 _misc_flags &= ~_misc_has_nonstatic_fields;
332 }
333 }
334
335 // field sizes
336 int nonstatic_field_size() const { return _nonstatic_field_size; }
337 void set_nonstatic_field_size(int size) { _nonstatic_field_size = size; }
338
339 int static_field_size() const { return _static_field_size; }
340 void set_static_field_size(int size) { _static_field_size = size; }
341
342 int static_oop_field_count() const { return (int)_static_oop_field_count; }
343 void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
344
345 // Java vtable
346 int vtable_length() const { return _vtable_len; }
347 void set_vtable_length(int len) { _vtable_len = len; }
348
349 // Java itable
350 int itable_length() const { return _itable_len; }
351 void set_itable_length(int len) { _itable_len = len; }
352
353 // array klasses
354 Klass* array_klasses() const { return _array_klasses; }
355 void set_array_klasses(Klass* k) { _array_klasses = k; }
356
357 // methods
358 Array<Method*>* methods() const { return _methods; }
359 void set_methods(Array<Method*>* a) { _methods = a; }
360 Method* method_with_idnum(int idnum);
361 Method* method_with_orig_idnum(int idnum);
362 Method* method_with_orig_idnum(int idnum, int version);
363
364 // method ordering
365 Array<int>* method_ordering() const { return _method_ordering; }
366 void set_method_ordering(Array<int>* m) { _method_ordering = m; }
367 void copy_method_ordering(intArray* m, TRAPS);
368
369 // default_methods
370 Array<Method*>* default_methods() const { return _default_methods; }
371 void set_default_methods(Array<Method*>* a) { _default_methods = a; }
372
373 // default method vtable_indices
374 Array<int>* default_vtable_indices() const { return _default_vtable_indices; }
375 void set_default_vtable_indices(Array<int>* v) { _default_vtable_indices = v; }
376 Array<int>* create_new_default_vtable_indices(int len, TRAPS);
377
378 // interfaces
379 Array<Klass*>* local_interfaces() const { return _local_interfaces; }
380 void set_local_interfaces(Array<Klass*>* a) {
381 guarantee(_local_interfaces == NULL || a == NULL, "Just checking");
382 _local_interfaces = a; }
383
384 Array<Klass*>* transitive_interfaces() const { return _transitive_interfaces; }
385 void set_transitive_interfaces(Array<Klass*>* a) {
386 guarantee(_transitive_interfaces == NULL || a == NULL, "Just checking");
387 _transitive_interfaces = a;
388 }
389
390 private:
391 friend class fieldDescriptor;
392 FieldInfo* field(int index) const { return FieldInfo::from_field_array(_fields, index); }
393
394 public:
395 int field_offset (int index) const { return field(index)->offset(); }
396 int field_access_flags(int index) const { return field(index)->access_flags(); }
397 Symbol* field_name (int index) const { return field(index)->name(constants()); }
398 Symbol* field_signature (int index) const { return field(index)->signature(constants()); }
399
400 // Number of Java declared fields
401 int java_fields_count() const { return (int)_java_fields_count; }
402
403 Array<u2>* fields() const { return _fields; }
404 void set_fields(Array<u2>* f, u2 java_fields_count) {
405 guarantee(_fields == NULL || f == NULL, "Just checking");
406 _fields = f;
407 _java_fields_count = java_fields_count;
408 }
409
410 // inner classes
411 Array<u2>* inner_classes() const { return _inner_classes; }
412 void set_inner_classes(Array<u2>* f) { _inner_classes = f; }
413
414 enum InnerClassAttributeOffset {
415 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
416 inner_class_inner_class_info_offset = 0,
417 inner_class_outer_class_info_offset = 1,
418 inner_class_inner_name_offset = 2,
419 inner_class_access_flags_offset = 3,
420 inner_class_next_offset = 4
421 };
422
423 enum EnclosingMethodAttributeOffset {
424 enclosing_method_class_index_offset = 0,
425 enclosing_method_method_index_offset = 1,
426 enclosing_method_attribute_size = 2
427 };
428
429 // method override check
430 bool is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS);
431
432 // package
433 bool is_same_class_package(Klass* class2);
434 bool is_same_class_package(oop classloader2, Symbol* classname2);
435 static bool is_same_class_package(oop class_loader1, Symbol* class_name1, oop class_loader2, Symbol* class_name2);
436
437 // find an enclosing class (defined where original code was, in jvm.cpp!)
438 Klass* compute_enclosing_class(bool* inner_is_member, TRAPS) {
439 instanceKlassHandle self(THREAD, this);
440 return compute_enclosing_class_impl(self, inner_is_member, THREAD);
441 }
442 static Klass* compute_enclosing_class_impl(instanceKlassHandle self,
443 bool* inner_is_member, TRAPS);
444
445 // tell if two classes have the same enclosing class (at package level)
446 bool is_same_package_member(Klass* class2, TRAPS) {
447 instanceKlassHandle self(THREAD, this);
448 return is_same_package_member_impl(self, class2, THREAD);
449 }
450 static bool is_same_package_member_impl(instanceKlassHandle self,
451 Klass* class2, TRAPS);
452
453 // initialization state
454 bool is_loaded() const { return _init_state >= loaded; }
455 bool is_linked() const { return _init_state >= linked; }
456 bool is_initialized() const { return _init_state == fully_initialized; }
457 bool is_not_initialized() const { return _init_state < being_initialized; }
458 bool is_being_initialized() const { return _init_state == being_initialized; }
459 bool is_in_error_state() const { return _init_state == initialization_error; }
460 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; }
461 ClassState init_state() { return (ClassState)_init_state; }
462 bool is_rewritten() const { return (_misc_flags & _misc_rewritten) != 0; }
463
464 // defineClass specified verification
465 bool should_verify_class() const {
466 return (_misc_flags & _misc_should_verify_class) != 0;
467 }
468 void set_should_verify_class(bool value) {
469 if (value) {
470 _misc_flags |= _misc_should_verify_class;
471 } else {
472 _misc_flags &= ~_misc_should_verify_class;
473 }
474 }
475
476 // marking
477 bool is_marked_dependent() const { return _is_marked_dependent; }
478 void set_is_marked_dependent(bool value) { _is_marked_dependent = value; }
479
480 bool has_unloaded_dependent() const { return _has_unloaded_dependent; }
481 void set_has_unloaded_dependent(bool value) { _has_unloaded_dependent = value; }
482
483 // initialization (virtuals from Klass)
484 bool should_be_initialized() const; // means that initialize should be called
485 void initialize(TRAPS);
486 void link_class(TRAPS);
487 bool link_class_or_fail(TRAPS); // returns false on failure
488 void unlink_class();
489 void rewrite_class(TRAPS);
490 void link_methods(TRAPS);
491 Method* class_initializer();
492
493 // set the class to initialized if no static initializer is present
494 void eager_initialize(Thread *thread);
495
496 // reference type
497 ReferenceType reference_type() const { return (ReferenceType)_reference_type; }
498 void set_reference_type(ReferenceType t) {
499 assert(t == (u1)t, "overflow");
500 _reference_type = (u1)t;
501 }
502
503 static ByteSize reference_type_offset() { return in_ByteSize(offset_of(InstanceKlass, _reference_type)); }
504
505 // find local field, returns true if found
506 bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
507 // find field in direct superinterfaces, returns the interface in which the field is defined
508 Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
509 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
510 Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
511 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
512 Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
513
514 // find a non-static or static field given its offset within the class.
515 bool contains_field_offset(int offset) {
516 return instanceOopDesc::contains_field_offset(offset, nonstatic_field_size());
517 }
518
519 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
520 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
521
522 // find a local method (returns NULL if not found)
523 Method* find_method(Symbol* name, Symbol* signature) const;
524 static Method* find_method(Array<Method*>* methods, Symbol* name, Symbol* signature);
525
526 // find a local method, but skip static methods
527 Method* find_instance_method(Symbol* name, Symbol* signature);
528 static Method* find_instance_method(Array<Method*>* methods, Symbol* name, Symbol* signature);
529
530 // true if method matches signature and conforms to skipping_X conditions.
531 static bool method_matches(Method* m, Symbol* signature, bool skipping_overpass, bool skipping_static);
532
533 // find a local method index in default_methods (returns -1 if not found)
534 static int find_method_index(Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass, bool skipping_static);
535
536 // lookup operation (returns NULL if not found)
537 Method* uncached_lookup_method(Symbol* name, Symbol* signature, MethodLookupMode mode) const;
538
539 // lookup a method in all the interfaces that this class implements
540 // (returns NULL if not found)
541 Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature, MethodLookupMode mode) const;
542
543 // lookup a method in local defaults then in all interfaces
544 // (returns NULL if not found)
545 Method* lookup_method_in_ordered_interfaces(Symbol* name, Symbol* signature) const;
546
547 // Find method indices by name. If a method with the specified name is
548 // found the index to the first method is returned, and 'end' is filled in
549 // with the index of first non-name-matching method. If no method is found
550 // -1 is returned.
551 int find_method_by_name(Symbol* name, int* end);
552 static int find_method_by_name(Array<Method*>* methods, Symbol* name, int* end);
553
554 // constant pool
555 ConstantPool* constants() const { return _constants; }
556 void set_constants(ConstantPool* c) { _constants = c; }
557
558 // protection domain
559 oop protection_domain() const;
560
561 // signers
562 objArrayOop signers() const;
563
564 // host class
565 Klass* host_klass() const {
566 Klass** hk = (Klass**)adr_host_klass();
567 if (hk == NULL) {
568 return NULL;
569 } else {
570 assert(*hk != NULL, "host klass should always be set if the address is not null");
571 return *hk;
572 }
573 }
574 void set_host_klass(Klass* host) {
575 assert(is_anonymous(), "not anonymous");
576 Klass** addr = (Klass**)adr_host_klass();
577 assert(addr != NULL, "no reversed space");
578 if (addr != NULL) {
579 *addr = host;
580 }
581 }
582 bool is_anonymous() const {
583 return (_misc_flags & _misc_is_anonymous) != 0;
584 }
585 void set_is_anonymous(bool value) {
586 if (value) {
587 _misc_flags |= _misc_is_anonymous;
588 } else {
589 _misc_flags &= ~_misc_is_anonymous;
590 }
591 }
592
593 // Oop that keeps the metadata for this class from being unloaded
594 // in places where the metadata is stored in other places, like nmethods
595 oop klass_holder() const {
596 return is_anonymous() ? java_mirror() : class_loader();
597 }
598
599 bool is_contended() const {
600 return (_misc_flags & _misc_is_contended) != 0;
601 }
602 void set_is_contended(bool value) {
603 if (value) {
604 _misc_flags |= _misc_is_contended;
605 } else {
606 _misc_flags &= ~_misc_is_contended;
607 }
608 }
609
610 // source file name
611 Symbol* source_file_name() const {
612 return (_source_file_name_index == 0) ?
613 (Symbol*)NULL : _constants->symbol_at(_source_file_name_index);
614 }
615 u2 source_file_name_index() const {
616 return _source_file_name_index;
617 }
618 void set_source_file_name_index(u2 sourcefile_index) {
619 _source_file_name_index = sourcefile_index;
620 }
621
622 // minor and major version numbers of class file
623 u2 minor_version() const { return _minor_version; }
624 void set_minor_version(u2 minor_version) { _minor_version = minor_version; }
625 u2 major_version() const { return _major_version; }
626 void set_major_version(u2 major_version) { _major_version = major_version; }
627
628 // source debug extension
629 char* source_debug_extension() const { return _source_debug_extension; }
630 void set_source_debug_extension(char* array, int length);
631
632 // symbol unloading support (refcount already added)
633 Symbol* array_name() { return _array_name; }
634 void set_array_name(Symbol* name) { assert(_array_name == NULL || name == NULL, "name already created"); _array_name = name; }
635
636 // nonstatic oop-map blocks
637 static int nonstatic_oop_map_size(unsigned int oop_map_count) {
638 return oop_map_count * OopMapBlock::size_in_words();
639 }
640 unsigned int nonstatic_oop_map_count() const {
641 return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
642 }
643 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
644 void set_nonstatic_oop_map_size(int words) {
645 _nonstatic_oop_map_size = words;
646 }
647
648 // RedefineClasses() support for previous versions:
649 void add_previous_version(instanceKlassHandle ikh, BitMap *emcp_methods,
650 int emcp_method_count);
651 // If the _previous_versions array is non-NULL, then this klass
652 // has been redefined at least once even if we aren't currently
653 // tracking a previous version.
654 bool has_been_redefined() const { return _previous_versions != NULL; }
655 bool has_previous_version() const;
656 void init_previous_versions() {
657 _previous_versions = NULL;
658 }
659 GrowableArray<PreviousVersionNode *>* previous_versions() const {
660 return _previous_versions;
661 }
662
663 InstanceKlass* get_klass_version(int version);
664 static void purge_previous_versions(InstanceKlass* ik);
665
666 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
667 void set_cached_class_file(JvmtiCachedClassFileData *data) {
668 _cached_class_file = data;
669 }
670 JvmtiCachedClassFileData * get_cached_class_file() { return _cached_class_file; }
671 jint get_cached_class_file_len();
672 unsigned char * get_cached_class_file_bytes();
673
674 // JVMTI: Support for caching of field indices, types, and offsets
675 void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
676 _jvmti_cached_class_field_map = descriptor;
677 }
678 JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
679 return _jvmti_cached_class_field_map;
680 }
681
682 bool has_default_methods() const {
683 return (_misc_flags & _misc_has_default_methods) != 0;
684 }
685 void set_has_default_methods(bool b) {
686 if (b) {
687 _misc_flags |= _misc_has_default_methods;
688 } else {
689 _misc_flags &= ~_misc_has_default_methods;
690 }
691 }
692
693 bool declares_default_methods() const {
694 return (_misc_flags & _misc_declares_default_methods) != 0;
695 }
696 void set_declares_default_methods(bool b) {
697 if (b) {
698 _misc_flags |= _misc_declares_default_methods;
699 } else {
700 _misc_flags &= ~_misc_declares_default_methods;
701 }
702 }
703
704 // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
705 inline u2 next_method_idnum();
706 void set_initial_method_idnum(u2 value) { _idnum_allocated_count = value; }
707
708 // generics support
709 Symbol* generic_signature() const {
710 return (_generic_signature_index == 0) ?
711 (Symbol*)NULL : _constants->symbol_at(_generic_signature_index);
712 }
713 u2 generic_signature_index() const {
714 return _generic_signature_index;
715 }
716 void set_generic_signature_index(u2 sig_index) {
717 _generic_signature_index = sig_index;
718 }
719
720 u2 enclosing_method_data(int offset);
721 u2 enclosing_method_class_index() {
722 return enclosing_method_data(enclosing_method_class_index_offset);
723 }
724 u2 enclosing_method_method_index() {
725 return enclosing_method_data(enclosing_method_method_index_offset);
726 }
727 void set_enclosing_method_indices(u2 class_index,
728 u2 method_index);
729
730 // jmethodID support
731 static jmethodID get_jmethod_id(instanceKlassHandle ik_h,
732 methodHandle method_h);
733 static jmethodID get_jmethod_id_fetch_or_update(instanceKlassHandle ik_h,
734 size_t idnum, jmethodID new_id, jmethodID* new_jmeths,
735 jmethodID* to_dealloc_id_p,
736 jmethodID** to_dealloc_jmeths_p);
737 static void get_jmethod_id_length_value(jmethodID* cache, size_t idnum,
738 size_t *length_p, jmethodID* id_p);
739 jmethodID jmethod_id_or_null(Method* method);
740
741 // annotations support
742 Annotations* annotations() const { return _annotations; }
743 void set_annotations(Annotations* anno) { _annotations = anno; }
744
745 AnnotationArray* class_annotations() const {
746 return (_annotations != NULL) ? _annotations->class_annotations() : NULL;
747 }
748 Array<AnnotationArray*>* fields_annotations() const {
749 return (_annotations != NULL) ? _annotations->fields_annotations() : NULL;
750 }
751 AnnotationArray* class_type_annotations() const {
752 return (_annotations != NULL) ? _annotations->class_type_annotations() : NULL;
753 }
754 Array<AnnotationArray*>* fields_type_annotations() const {
755 return (_annotations != NULL) ? _annotations->fields_type_annotations() : NULL;
756 }
757 // allocation
758 instanceOop allocate_instance(TRAPS);
759
760 // additional member function to return a handle
761 instanceHandle allocate_instance_handle(TRAPS) { return instanceHandle(THREAD, allocate_instance(THREAD)); }
762
763 objArrayOop allocate_objArray(int n, int length, TRAPS);
764 // Helper function
765 static instanceOop register_finalizer(instanceOop i, TRAPS);
766
767 // Check whether reflection/jni/jvm code is allowed to instantiate this class;
768 // if not, throw either an Error or an Exception.
769 virtual void check_valid_for_instantiation(bool throwError, TRAPS);
770
771 // initialization
772 void call_class_initializer(TRAPS);
773 void set_initialization_state_and_notify(ClassState state, TRAPS);
774
775 // OopMapCache support
776 OopMapCache* oop_map_cache() { return _oop_map_cache; }
777 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
778 void mask_for(methodHandle method, int bci, InterpreterOopMap* entry);
779
780 // JNI identifier support (for static fields - for jni performance)
781 JNIid* jni_ids() { return _jni_ids; }
782 void set_jni_ids(JNIid* ids) { _jni_ids = ids; }
783 JNIid* jni_id_for(int offset);
784
785 // maintenance of deoptimization dependencies
786 int mark_dependent_nmethods(DepChange& changes);
787 void add_dependent_nmethod(nmethod* nm);
788 void remove_dependent_nmethod(nmethod* nm);
789
790 // On-stack replacement support
791 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; };
792 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; };
793 void add_osr_nmethod(nmethod* n);
794 void remove_osr_nmethod(nmethod* n);
795 int mark_osr_nmethods(const Method* m);
796 nmethod* lookup_osr_nmethod(const Method* m, int bci, int level, bool match_level) const;
797
798 // Breakpoint support (see methods on Method* for details)
799 BreakpointInfo* breakpoints() const { return _breakpoints; };
800 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
801
802 // support for stub routines
803 static ByteSize init_state_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_state)); }
804 TRACE_DEFINE_OFFSET;
805 static ByteSize init_thread_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_thread)); }
806
807 // subclass/subinterface checks
808 bool implements_interface(Klass* k) const;
809 bool is_same_or_direct_interface(Klass* k) const;
810
811 // Access to the implementor of an interface.
812 Klass* implementor() const
813 {
814 Klass** k = adr_implementor();
815 if (k == NULL) {
816 return NULL;
817 } else {
818 return *k;
819 }
820 }
821
822 void set_implementor(Klass* k) {
823 assert(is_interface(), "not interface");
824 Klass** addr = adr_implementor();
825 assert(addr != NULL, "null addr");
826 if (addr != NULL) {
827 *addr = k;
828 }
829 }
830
831 int nof_implementors() const {
832 Klass* k = implementor();
833 if (k == NULL) {
834 return 0;
835 } else if (k != this) {
836 return 1;
837 } else {
838 return 2;
839 }
840 }
841
842 void add_implementor(Klass* k); // k is a new class that implements this interface
843 void init_implementor(); // initialize
844
845 // link this class into the implementors list of every interface it implements
846 void process_interfaces(Thread *thread);
847
848 // virtual operations from Klass
849 bool is_leaf_class() const { return _subklass == NULL; }
850 GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots);
851 bool compute_is_subtype_of(Klass* k);
852 bool can_be_primary_super_slow() const;
853 int oop_size(oop obj) const { return size_helper(); }
854 bool oop_is_instance_slow() const { return true; }
855
856 // Iterators
857 void do_local_static_fields(FieldClosure* cl);
858 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
859 void do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle, TRAPS);
860
861 void methods_do(void f(Method* method));
862 void array_klasses_do(void f(Klass* k));
863 void array_klasses_do(void f(Klass* k, TRAPS), TRAPS);
864 bool super_types_do(SuperTypeClosure* blk);
865
866 // Casting from Klass*
867 static InstanceKlass* cast(Klass* k) {
868 assert(k->is_klass(), "must be");
869 assert(k->oop_is_instance(), "cast to InstanceKlass");
870 return (InstanceKlass*) k;
871 }
872
873 InstanceKlass* java_super() const {
874 return (super() == NULL) ? NULL : cast(super());
875 }
876
877 // Sizing (in words)
878 static int header_size() { return align_object_offset(sizeof(InstanceKlass)/HeapWordSize); }
879
880 static int size(int vtable_length, int itable_length,
881 int nonstatic_oop_map_size,
882 bool is_interface, bool is_anonymous) {
883 return align_object_size(header_size() +
884 align_object_offset(vtable_length) +
885 align_object_offset(itable_length) +
886 ((is_interface || is_anonymous) ?
887 align_object_offset(nonstatic_oop_map_size) :
888 nonstatic_oop_map_size) +
889 (is_interface ? (int)sizeof(Klass*)/HeapWordSize : 0) +
890 (is_anonymous ? (int)sizeof(Klass*)/HeapWordSize : 0));
891 }
892 int size() const { return size(vtable_length(),
893 itable_length(),
894 nonstatic_oop_map_size(),
895 is_interface(),
896 is_anonymous());
897 }
898 #if INCLUDE_SERVICES
899 virtual void collect_statistics(KlassSizeStats *sz) const;
900 #endif
901
902 static int vtable_start_offset() { return header_size(); }
903 static int vtable_length_offset() { return offset_of(InstanceKlass, _vtable_len) / HeapWordSize; }
904
905 intptr_t* start_of_vtable() const { return ((intptr_t*)this) + vtable_start_offset(); }
906 intptr_t* start_of_itable() const { return start_of_vtable() + align_object_offset(vtable_length()); }
907 int itable_offset_in_words() const { return start_of_itable() - (intptr_t*)this; }
908
909 intptr_t* end_of_itable() const { return start_of_itable() + itable_length(); }
910
911 address static_field_addr(int offset);
912
913 OopMapBlock* start_of_nonstatic_oop_maps() const {
914 return (OopMapBlock*)(start_of_itable() + align_object_offset(itable_length()));
915 }
916
917 Klass** end_of_nonstatic_oop_maps() const {
918 return (Klass**)(start_of_nonstatic_oop_maps() +
919 nonstatic_oop_map_count());
920 }
921
922 Klass** adr_implementor() const {
923 if (is_interface()) {
924 return (Klass**)end_of_nonstatic_oop_maps();
925 } else {
926 return NULL;
927 }
928 };
929
930 Klass** adr_host_klass() const {
931 if (is_anonymous()) {
932 Klass** adr_impl = adr_implementor();
933 if (adr_impl != NULL) {
934 return adr_impl + 1;
935 } else {
936 return end_of_nonstatic_oop_maps();
937 }
938 } else {
939 return NULL;
940 }
941 }
942
943 // Use this to return the size of an instance in heap words:
944 int size_helper() const {
945 return layout_helper_to_size_helper(layout_helper());
946 }
947
948 // This bit is initialized in classFileParser.cpp.
949 // It is false under any of the following conditions:
950 // - the class is abstract (including any interface)
951 // - the class has a finalizer (if !RegisterFinalizersAtInit)
952 // - the class size is larger than FastAllocateSizeLimit
953 // - the class is java/lang/Class, which cannot be allocated directly
954 bool can_be_fastpath_allocated() const {
955 return !layout_helper_needs_slow_path(layout_helper());
956 }
957
958 // Java vtable/itable
959 klassVtable* vtable() const; // return new klassVtable wrapper
960 inline Method* method_at_vtable(int index);
961 klassItable* itable() const; // return new klassItable wrapper
962 Method* method_at_itable(Klass* holder, int index, TRAPS);
963
964 #if INCLUDE_JVMTI
965 void adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed);
966 #endif // INCLUDE_JVMTI
967
968 // Garbage collection
969 void oop_follow_contents(oop obj);
970 int oop_adjust_pointers(oop obj);
971
972 void clean_implementors_list(BoolObjectClosure* is_alive);
973 void clean_method_data(BoolObjectClosure* is_alive);
974 void clean_dependent_nmethods();
975
976 // Explicit metaspace deallocation of fields
977 // For RedefineClasses and class file parsing errors, we need to deallocate
978 // instanceKlasses and the metadata they point to.
979 void deallocate_contents(ClassLoaderData* loader_data);
980 static void deallocate_methods(ClassLoaderData* loader_data,
981 Array<Method*>* methods);
982 void static deallocate_interfaces(ClassLoaderData* loader_data,
983 Klass* super_klass,
984 Array<Klass*>* local_interfaces,
985 Array<Klass*>* transitive_interfaces);
986
987 // The constant pool is on stack if any of the methods are executing or
988 // referenced by handles.
989 bool on_stack() const { return _constants->on_stack(); }
990
991 // callbacks for actions during class unloading
992 static void notify_unload_class(InstanceKlass* ik);
993 static void release_C_heap_structures(InstanceKlass* ik);
994
995 // Parallel Scavenge and Parallel Old
996 PARALLEL_GC_DECLS
997
998 // Naming
999 const char* signature_name() const;
1000
1001 // Iterators
1002 int oop_oop_iterate(oop obj, ExtendedOopClosure* blk) {
1003 return oop_oop_iterate_v(obj, blk);
1004 }
1005
1006 int oop_oop_iterate_m(oop obj, ExtendedOopClosure* blk, MemRegion mr) {
1007 return oop_oop_iterate_v_m(obj, blk, mr);
1008 }
1009
1010 #define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix) \
1011 int oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk); \
1012 int oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk, \
1013 MemRegion mr);
1014
1015 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL)
1016 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DECL)
1017
1018 #if INCLUDE_ALL_GCS
1019 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \
1020 int oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* blk);
1021
1022 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
1023 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
1024 #endif // INCLUDE_ALL_GCS
1025
1026 u2 idnum_allocated_count() const { return _idnum_allocated_count; }
1027
1028 public:
1029 void set_in_error_state() {
1030 assert(DumpSharedSpaces, "only call this when dumping archive");
1031 _init_state = initialization_error;
1032 }
1033 bool check_sharing_error_state();
1034
1035 private:
1036 // initialization state
1037 #ifdef ASSERT
1038 void set_init_state(ClassState state);
1039 #else
1040 void set_init_state(ClassState state) { _init_state = (u1)state; }
1041 #endif
1042 void set_rewritten() { _misc_flags |= _misc_rewritten; }
1043 void set_init_thread(Thread *thread) { _init_thread = thread; }
1044
1045 // The RedefineClasses() API can cause new method idnums to be needed
1046 // which will cause the caches to grow. Safety requires different
1047 // cache management logic if the caches can grow instead of just
1048 // going from NULL to non-NULL.
1049 bool idnum_can_increment() const { return has_been_redefined(); }
1050 jmethodID* methods_jmethod_ids_acquire() const
1051 { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); }
1052 void release_set_methods_jmethod_ids(jmethodID* jmeths)
1053 { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); }
1054
1055 // Lock during initialization
1056 public:
1057 // Lock for (1) initialization; (2) access to the ConstantPool of this class.
1058 // Must be one per class and it has to be a VM internal object so java code
1059 // cannot lock it (like the mirror).
1060 // It has to be an object not a Mutex because it's held through java calls.
1061 oop init_lock() const;
1062 private:
1063 void fence_and_clear_init_lock();
1064
1065 // Static methods that are used to implement member methods where an exposed this pointer
1066 // is needed due to possible GCs
1067 static bool link_class_impl (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
1068 static bool verify_code (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
1069 static void initialize_impl (instanceKlassHandle this_oop, TRAPS);
1070 static void initialize_super_interfaces (instanceKlassHandle this_oop, TRAPS);
1071 static void eager_initialize_impl (instanceKlassHandle this_oop);
1072 static void set_initialization_state_and_notify_impl (instanceKlassHandle this_oop, ClassState state, TRAPS);
1073 static void call_class_initializer_impl (instanceKlassHandle this_oop, TRAPS);
1074 static Klass* array_klass_impl (instanceKlassHandle this_oop, bool or_null, int n, TRAPS);
1075 static void do_local_static_fields_impl (instanceKlassHandle this_oop, void f(fieldDescriptor* fd, Handle, TRAPS), Handle, TRAPS);
1076 /* jni_id_for_impl for jfieldID only */
1077 static JNIid* jni_id_for_impl (instanceKlassHandle this_oop, int offset);
1078
1079 // Returns the array class for the n'th dimension
1080 Klass* array_klass_impl(bool or_null, int n, TRAPS);
1081
1082 // Returns the array class with this class as element type
1083 Klass* array_klass_impl(bool or_null, TRAPS);
1084
1085 // find a local method (returns NULL if not found)
1086 Method* find_method_impl(Symbol* name, Symbol* signature, bool skipping_overpass) const;
1087 static Method* find_method_impl(Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass, bool skipping_static);
1088
1089 // Free CHeap allocated fields.
1090 void release_C_heap_structures();
1091 public:
1092 // CDS support - remove and restore oops from metadata. Oops are not shared.
1093 virtual void remove_unshareable_info();
1094 virtual void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS);
1095
1096 // jvm support
1097 jint compute_modifier_flags(TRAPS) const;
1098
1099 // JSR-292 support
1100 MemberNameTable* member_names() { return _member_names; }
1101 void set_member_names(MemberNameTable* member_names) { _member_names = member_names; }
1102 bool add_member_name(Handle member_name);
1103
1104 public:
1105 // JVMTI support
1106 jint jvmti_class_status() const;
1107
1108 public:
1109 // Printing
1110 #ifndef PRODUCT
1111 void print_on(outputStream* st) const;
1112 #endif
1113 void print_value_on(outputStream* st) const;
1114
1115 void oop_print_value_on(oop obj, outputStream* st);
1116
1117 #ifndef PRODUCT
1118 void oop_print_on (oop obj, outputStream* st);
1119
1120 void print_dependent_nmethods(bool verbose = false);
1121 bool is_dependent_nmethod(nmethod* nm);
1122 #endif
1123
1124 const char* internal_name() const;
1125
1126 // Verification
1127 void verify_on(outputStream* st);
1128
1129 void oop_verify_on(oop obj, outputStream* st);
1130 };
1131
1132 inline Method* InstanceKlass::method_at_vtable(int index) {
1133 #ifndef PRODUCT
1134 assert(index >= 0, "valid vtable index");
1135 if (DebugVtables) {
1136 verify_vtable_index(index);
1137 }
1138 #endif
1139 vtableEntry* ve = (vtableEntry*)start_of_vtable();
1140 return ve[index].method();
1141 }
1142
1143 // for adding methods
1144 // UNSET_IDNUM return means no more ids available
1145 inline u2 InstanceKlass::next_method_idnum() {
1146 if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1147 return ConstMethod::UNSET_IDNUM; // no more ids available
1148 } else {
1149 return _idnum_allocated_count++;
1150 }
1151 }
1152
1153
1154 /* JNIid class for jfieldIDs only */
1155 class JNIid: public CHeapObj<mtClass> {
1156 friend class VMStructs;
1157 private:
1158 Klass* _holder;
1159 JNIid* _next;
1160 int _offset;
1161 #ifdef ASSERT
1162 bool _is_static_field_id;
1163 #endif
1164
1165 public:
1166 // Accessors
1167 Klass* holder() const { return _holder; }
1168 int offset() const { return _offset; }
1169 JNIid* next() { return _next; }
1170 // Constructor
1171 JNIid(Klass* holder, int offset, JNIid* next);
1172 // Identifier lookup
1173 JNIid* find(int offset);
1174
1175 bool find_local_field(fieldDescriptor* fd) {
1176 return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1177 }
1178
1179 static void deallocate(JNIid* id);
1180 // Debugging
1181 #ifdef ASSERT
1182 bool is_static_field_id() const { return _is_static_field_id; }
1183 void set_is_static_field_id() { _is_static_field_id = true; }
1184 #endif
1185 void verify(Klass* holder);
1186 };
1187
1188
1189 // If breakpoints are more numerous than just JVMTI breakpoints,
1190 // consider compressing this data structure.
1191 // It is currently a simple linked list defined in method.hpp.
1192
1193 class BreakpointInfo;
1194
1195
1196 // A collection point for interesting information about the previous
1197 // version(s) of an InstanceKlass. A GrowableArray of PreviousVersionNodes
1198 // is attached to the InstanceKlass as needed. See PreviousVersionWalker below.
1199 class PreviousVersionNode : public CHeapObj<mtClass> {
1200 private:
1201 ConstantPool* _prev_constant_pool;
1202
1203 // If the previous version of the InstanceKlass doesn't have any
1204 // EMCP methods, then _prev_EMCP_methods will be NULL. If all the
1205 // EMCP methods have been collected, then _prev_EMCP_methods can
1206 // have a length of zero.
1207 GrowableArray<Method*>* _prev_EMCP_methods;
1208
1209 public:
1210 PreviousVersionNode(ConstantPool* prev_constant_pool,
1211 GrowableArray<Method*>* prev_EMCP_methods);
1212 ~PreviousVersionNode();
1213 ConstantPool* prev_constant_pool() const {
1214 return _prev_constant_pool;
1215 }
1216 GrowableArray<Method*>* prev_EMCP_methods() const {
1217 return _prev_EMCP_methods;
1218 }
1219 };
1220
1221
1222 // Helper object for walking previous versions.
1223 class PreviousVersionWalker : public StackObj {
1224 private:
1225 Thread* _thread;
1226 GrowableArray<PreviousVersionNode *>* _previous_versions;
1227 int _current_index;
1228
1229 // A pointer to the current node object so we can handle the deletes.
1230 PreviousVersionNode* _current_p;
1231
1232 // The constant pool handle keeps all the methods in this class from being
1233 // deallocated from the metaspace during class unloading.
1234 constantPoolHandle _current_constant_pool_handle;
1235
1236 public:
1237 PreviousVersionWalker(Thread* thread, InstanceKlass *ik);
1238
1239 // Return the interesting information for the next previous version
1240 // of the klass. Returns NULL if there are no more previous versions.
1241 PreviousVersionNode* next_previous_version();
1242 };
1243
1244
1245 //
1246 // nmethodBucket is used to record dependent nmethods for
1247 // deoptimization. nmethod dependencies are actually <klass, method>
1248 // pairs but we really only care about the klass part for purposes of
1249 // finding nmethods which might need to be deoptimized. Instead of
1250 // recording the method, a count of how many times a particular nmethod
1251 // was recorded is kept. This ensures that any recording errors are
1252 // noticed since an nmethod should be removed as many times are it's
1253 // added.
1254 //
1255 class nmethodBucket: public CHeapObj<mtClass> {
1256 friend class VMStructs;
1257 private:
1258 nmethod* _nmethod;
1259 int _count;
1260 nmethodBucket* _next;
1261
1262 public:
1263 nmethodBucket(nmethod* nmethod, nmethodBucket* next) {
1264 _nmethod = nmethod;
1265 _next = next;
1266 _count = 1;
1267 }
1268 int count() { return _count; }
1269 int increment() { _count += 1; return _count; }
1270 int decrement();
1271 nmethodBucket* next() { return _next; }
1272 void set_next(nmethodBucket* b) { _next = b; }
1273 nmethod* get_nmethod() { return _nmethod; }
1274 };
1275
1276 // An iterator that's used to access the inner classes indices in the
1277 // InstanceKlass::_inner_classes array.
1278 class InnerClassesIterator : public StackObj {
1279 private:
1280 Array<jushort>* _inner_classes;
1281 int _length;
1282 int _idx;
1283 public:
1284
1285 InnerClassesIterator(instanceKlassHandle k) {
1286 _inner_classes = k->inner_classes();
1287 if (k->inner_classes() != NULL) {
1288 _length = _inner_classes->length();
1289 // The inner class array's length should be the multiple of
1290 // inner_class_next_offset if it only contains the InnerClasses
1291 // attribute data, or it should be
1292 // n*inner_class_next_offset+enclosing_method_attribute_size
1293 // if it also contains the EnclosingMethod data.
1294 assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1295 _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1296 "just checking");
1297 // Remove the enclosing_method portion if exists.
1298 if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1299 _length -= InstanceKlass::enclosing_method_attribute_size;
1300 }
1301 } else {
1302 _length = 0;
1303 }
1304 _idx = 0;
1305 }
1306
1307 int length() const {
1308 return _length;
1309 }
1310
1311 void next() {
1312 _idx += InstanceKlass::inner_class_next_offset;
1313 }
1314
1315 bool done() const {
1316 return (_idx >= _length);
1317 }
1318
1319 u2 inner_class_info_index() const {
1320 return _inner_classes->at(
1321 _idx + InstanceKlass::inner_class_inner_class_info_offset);
1322 }
1323
1324 void set_inner_class_info_index(u2 index) {
1325 _inner_classes->at_put(
1326 _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1327 }
1328
1329 u2 outer_class_info_index() const {
1330 return _inner_classes->at(
1331 _idx + InstanceKlass::inner_class_outer_class_info_offset);
1332 }
1333
1334 void set_outer_class_info_index(u2 index) {
1335 _inner_classes->at_put(
1336 _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1337 }
1338
1339 u2 inner_name_index() const {
1340 return _inner_classes->at(
1341 _idx + InstanceKlass::inner_class_inner_name_offset);
1342 }
1343
1344 void set_inner_name_index(u2 index) {
1345 _inner_classes->at_put(
1346 _idx + InstanceKlass::inner_class_inner_name_offset, index);
1347 }
1348
1349 u2 inner_access_flags() const {
1350 return _inner_classes->at(
1351 _idx + InstanceKlass::inner_class_access_flags_offset);
1352 }
1353 };
1354
1355 #endif // SHARE_VM_OOPS_INSTANCEKLASS_HPP