1 /*
2 * Copyright (c) 1997, 2024, 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_OOPS_INSTANCEKLASS_HPP
26 #define SHARE_OOPS_INSTANCEKLASS_HPP
27
28 #include "memory/referenceType.hpp"
29 #include "oops/annotations.hpp"
30 #include "oops/constMethod.hpp"
31 #include "oops/fieldInfo.hpp"
32 #include "oops/instanceKlassFlags.hpp"
33 #include "oops/instanceOop.hpp"
34 #include "runtime/handles.hpp"
35 #include "runtime/javaThread.hpp"
36 #include "utilities/accessFlags.hpp"
37 #include "utilities/align.hpp"
38 #include "utilities/growableArray.hpp"
39 #include "utilities/macros.hpp"
40 #if INCLUDE_JFR
41 #include "jfr/support/jfrKlassExtension.hpp"
42 #endif
43
44 class ConstantPool;
45 class DeoptimizationScope;
46 class klassItable;
47 class Monitor;
48 class RecordComponent;
49
50 // An InstanceKlass is the VM level representation of a Java class.
51 // It contains all information needed for at class at execution runtime.
52
53 // InstanceKlass embedded field layout (after declared fields):
54 // [EMBEDDED Java vtable ] size in words = vtable_len
55 // [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
56 // The embedded nonstatic oop-map blocks are short pairs (offset, length)
57 // indicating where oops are located in instances of this klass.
58 // [EMBEDDED implementor of the interface] only exist for interface
59
60
61 // forward declaration for class -- see below for definition
62 #if INCLUDE_JVMTI
63 class BreakpointInfo;
64 #endif
65 class ClassFileParser;
66 class ClassFileStream;
67 class KlassDepChange;
68 class DependencyContext;
69 class fieldDescriptor;
70 class jniIdMapBase;
71 class JNIid;
72 class JvmtiCachedClassFieldMap;
73 class nmethodBucket;
74 class OopMapCache;
75 class InterpreterOopMap;
76 class PackageEntry;
77 class ModuleEntry;
78
79 // This is used in iterators below.
80 class FieldClosure: public StackObj {
81 public:
82 virtual void do_field(fieldDescriptor* fd) = 0;
83 };
84
85 // Print fields.
86 // If "obj" argument to constructor is null, prints static fields, otherwise prints non-static fields.
87 class FieldPrinter: public FieldClosure {
88 oop _obj;
89 outputStream* _st;
90 public:
91 FieldPrinter(outputStream* st, oop obj = nullptr) : _obj(obj), _st(st) {}
92 void do_field(fieldDescriptor* fd);
93 };
94
95 // Describes where oops are located in instances of this klass.
96 class OopMapBlock {
97 public:
98 // Byte offset of the first oop mapped by this block.
99 int offset() const { return _offset; }
100 void set_offset(int offset) { _offset = offset; }
101
102 // Number of oops in this block.
103 uint count() const { return _count; }
104 void set_count(uint count) { _count = count; }
105
106 void increment_count(int diff) { _count += diff; }
107
108 int offset_span() const { return _count * heapOopSize; }
109
110 int end_offset() const {
111 return offset() + offset_span();
112 }
113
114 bool is_contiguous(int another_offset) const {
115 return another_offset == end_offset();
116 }
117
118 // sizeof(OopMapBlock) in words.
119 static int size_in_words() {
120 return align_up((int)sizeof(OopMapBlock), wordSize) >>
121 LogBytesPerWord;
122 }
123
124 static int compare_offset(const OopMapBlock* a, const OopMapBlock* b) {
125 return a->offset() - b->offset();
126 }
127
128 private:
129 int _offset;
130 uint _count;
131 };
132
133 struct JvmtiCachedClassFileData;
134
135 class InstanceKlass: public Klass {
136 friend class VMStructs;
137 friend class JVMCIVMStructs;
138 friend class ClassFileParser;
139 friend class CompileReplay;
140
141 public:
142 static const KlassKind Kind = InstanceKlassKind;
143
144 protected:
145 InstanceKlass(const ClassFileParser& parser, KlassKind kind = Kind, ReferenceType reference_type = REF_NONE);
146
147 public:
148 InstanceKlass();
149
150 // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
151 // of the class loading & initialization procedure, and the use of the states.
152 enum ClassState : u1 {
153 allocated, // allocated (but not yet linked)
154 loaded, // loaded and inserted in class hierarchy (but not linked yet)
155 linked, // successfully linked/verified (but not initialized yet)
156 being_initialized, // currently running class initializer
157 fully_initialized, // initialized (successful final state)
158 initialization_error // error happened during initialization
159 };
160
161 private:
162 static InstanceKlass* allocate_instance_klass(const ClassFileParser& parser, TRAPS);
163
164 protected:
165 // If you add a new field that points to any metaspace object, you
166 // must add this field to InstanceKlass::metaspace_pointers_do().
167
168 // Annotations for this class
169 Annotations* _annotations;
170 // Package this class is defined in
171 PackageEntry* _package_entry;
172 // Array classes holding elements of this class.
173 ObjArrayKlass* volatile _array_klasses;
174 // Constant pool for this class.
175 ConstantPool* _constants;
176 // The InnerClasses attribute and EnclosingMethod attribute. The
177 // _inner_classes is an array of shorts. If the class has InnerClasses
178 // attribute, then the _inner_classes array begins with 4-tuples of shorts
179 // [inner_class_info_index, outer_class_info_index,
180 // inner_name_index, inner_class_access_flags] for the InnerClasses
181 // attribute. If the EnclosingMethod attribute exists, it occupies the
182 // last two shorts [class_index, method_index] of the array. If only
183 // the InnerClasses attribute exists, the _inner_classes array length is
184 // number_of_inner_classes * 4. If the class has both InnerClasses
185 // and EnclosingMethod attributes the _inner_classes array length is
186 // number_of_inner_classes * 4 + enclosing_method_attribute_size.
187 Array<jushort>* _inner_classes;
188
189 // The NestMembers attribute. An array of shorts, where each is a
190 // class info index for the class that is a nest member. This data
191 // has not been validated.
192 Array<jushort>* _nest_members;
193
194 // Resolved nest-host klass: either true nest-host or self if we are not
195 // nested, or an error occurred resolving or validating the nominated
196 // nest-host. Can also be set directly by JDK API's that establish nest
197 // relationships.
198 // By always being set it makes nest-member access checks simpler.
199 InstanceKlass* _nest_host;
200
201 // The PermittedSubclasses attribute. An array of shorts, where each is a
202 // class info index for the class that is a permitted subclass.
203 Array<jushort>* _permitted_subclasses;
204
205 // The contents of the Record attribute.
206 Array<RecordComponent*>* _record_components;
207
208 // the source debug extension for this klass, null if not specified.
209 // Specified as UTF-8 string without terminating zero byte in the classfile,
210 // it is stored in the instanceklass as a null-terminated UTF-8 string
211 const char* _source_debug_extension;
212
213 // Number of heapOopSize words used by non-static fields in this klass
214 // (including inherited fields but after header_size()).
215 int _nonstatic_field_size;
216 int _static_field_size; // number words used by static fields (oop and non-oop) in this klass
217 int _nonstatic_oop_map_size; // size in words of nonstatic oop map blocks
218 int _itable_len; // length of Java itable (in words)
219
220 // The NestHost attribute. The class info index for the class
221 // that is the nest-host of this class. This data has not been validated.
222 u2 _nest_host_index;
223 u2 _this_class_index; // constant pool entry
224 u2 _static_oop_field_count; // number of static oop fields in this klass
225
226 volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change
227
228 // _is_marked_dependent can be set concurrently, thus cannot be part of the
229 // _misc_flags.
230 bool _is_marked_dependent; // used for marking during flushing and deoptimization
231
232 // Class states are defined as ClassState (see above).
233 // Place the _init_state here to utilize the unused 2-byte after
234 // _idnum_allocated_count.
235 volatile ClassState _init_state; // state of class
236
237 u1 _reference_type; // reference type
238
239 // State is set either at parse time or while executing, atomically to not disturb other state
240 InstanceKlassFlags _misc_flags;
241
242 JavaThread* volatile _init_thread; // Pointer to current thread doing initialization (to handle recursive initialization)
243
244 OopMapCache* volatile _oop_map_cache; // OopMapCache for all methods in the klass (allocated lazily)
245 JNIid* _jni_ids; // First JNI identifier for static fields in this class
246 jmethodID* volatile _methods_jmethod_ids; // jmethodIDs corresponding to method_idnum, or null if none
247 nmethodBucket* volatile _dep_context; // packed DependencyContext structure
248 uint64_t volatile _dep_context_last_cleaned;
249 nmethod* _osr_nmethods_head; // Head of list of on-stack replacement nmethods for this class
250 #if INCLUDE_JVMTI
251 BreakpointInfo* _breakpoints; // bpt lists, managed by Method*
252 // Linked instanceKlasses of previous versions
253 InstanceKlass* _previous_versions;
254 // JVMTI fields can be moved to their own structure - see 6315920
255 // JVMTI: cached class file, before retransformable agent modified it in CFLH
256 JvmtiCachedClassFileData* _cached_class_file;
257 #endif
258
259 #if INCLUDE_JVMTI
260 JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration
261 #endif
262
263 NOT_PRODUCT(int _verify_count;) // to avoid redundant verifies
264 NOT_PRODUCT(volatile int _shared_class_load_count;) // ensure a shared class is loaded only once
265
266 // Method array.
267 Array<Method*>* _methods;
268 // Default Method Array, concrete methods inherited from interfaces
269 Array<Method*>* _default_methods;
270 // Interfaces (InstanceKlass*s) this class declares locally to implement.
271 Array<InstanceKlass*>* _local_interfaces;
272 // Interfaces (InstanceKlass*s) this class implements transitively.
273 Array<InstanceKlass*>* _transitive_interfaces;
274 // Int array containing the original order of method in the class file (for JVMTI).
275 Array<int>* _method_ordering;
276 // Int array containing the vtable_indices for default_methods
277 // offset matches _default_methods offset
278 Array<int>* _default_vtable_indices;
279
280 // Fields information is stored in an UNSIGNED5 encoded stream (see fieldInfo.hpp)
281 Array<u1>* _fieldinfo_stream;
282 Array<FieldStatus>* _fields_status;
283
284 // embedded Java vtable follows here
285 // embedded Java itables follows here
286 // embedded static fields follows here
287 // embedded nonstatic oop-map blocks follows here
288 // embedded implementor of this interface follows here
289 // The embedded implementor only exists if the current klass is an
290 // interface. The possible values of the implementor fall into following
291 // three cases:
292 // null: no implementor.
293 // A Klass* that's not itself: one implementor.
294 // Itself: more than one implementors.
295 //
296
297 friend class SystemDictionary;
298
299 static bool _disable_method_binary_search;
300
301 // Controls finalizer registration
302 static bool _finalization_enabled;
303
304 public:
305
306 // Queries finalization state
307 static bool is_finalization_enabled() { return _finalization_enabled; }
308
309 // Sets finalization state
310 static void set_finalization_enabled(bool val) { _finalization_enabled = val; }
311
312 // The three BUILTIN class loader types
313 bool is_shared_boot_class() const { return _misc_flags.is_shared_boot_class(); }
314 bool is_shared_platform_class() const { return _misc_flags.is_shared_platform_class(); }
315 bool is_shared_app_class() const { return _misc_flags.is_shared_app_class(); }
316 // The UNREGISTERED class loader type
317 bool is_shared_unregistered_class() const { return _misc_flags.is_shared_unregistered_class(); }
318
319 // Check if the class can be shared in CDS
320 bool is_shareable() const;
321
322 bool shared_loading_failed() const { return _misc_flags.shared_loading_failed(); }
323
324 void set_shared_loading_failed() { _misc_flags.set_shared_loading_failed(true); }
325
326 #if INCLUDE_CDS
327 int shared_class_loader_type() const;
328 void set_shared_class_loader_type(s2 loader_type) { _misc_flags.set_shared_class_loader_type(loader_type); }
329 void assign_class_loader_type() { _misc_flags.assign_class_loader_type(_class_loader_data); }
330 #endif
331
332 bool has_nonstatic_fields() const { return _misc_flags.has_nonstatic_fields(); }
333 void set_has_nonstatic_fields(bool b) { _misc_flags.set_has_nonstatic_fields(b); }
334
335 bool has_localvariable_table() const { return _misc_flags.has_localvariable_table(); }
336 void set_has_localvariable_table(bool b) { _misc_flags.set_has_localvariable_table(b); }
337
338 // field sizes
339 int nonstatic_field_size() const { return _nonstatic_field_size; }
340 void set_nonstatic_field_size(int size) { _nonstatic_field_size = size; }
341
342 int static_field_size() const { return _static_field_size; }
343 void set_static_field_size(int size) { _static_field_size = size; }
344
345 int static_oop_field_count() const { return (int)_static_oop_field_count; }
346 void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
347
348 // Java itable
349 int itable_length() const { return _itable_len; }
350 void set_itable_length(int len) { _itable_len = len; }
351
352 // array klasses
353 ObjArrayKlass* array_klasses() const { return _array_klasses; }
354 inline ObjArrayKlass* array_klasses_acquire() const; // load with acquire semantics
355 inline void release_set_array_klasses(ObjArrayKlass* k); // store with release semantics
356 void set_array_klasses(ObjArrayKlass* k) { _array_klasses = k; }
357
358 // methods
359 Array<Method*>* methods() const { return _methods; }
360 void set_methods(Array<Method*>* a) { _methods = a; }
361 Method* method_with_idnum(int idnum);
362 Method* method_with_orig_idnum(int idnum);
363 Method* method_with_orig_idnum(int idnum, int version);
364
365 // method ordering
366 Array<int>* method_ordering() const { return _method_ordering; }
367 void set_method_ordering(Array<int>* m) { _method_ordering = m; }
368 void copy_method_ordering(const intArray* m, TRAPS);
369
370 // default_methods
371 Array<Method*>* default_methods() const { return _default_methods; }
372 void set_default_methods(Array<Method*>* a) { _default_methods = a; }
373
374 // default method vtable_indices
375 Array<int>* default_vtable_indices() const { return _default_vtable_indices; }
376 void set_default_vtable_indices(Array<int>* v) { _default_vtable_indices = v; }
377 Array<int>* create_new_default_vtable_indices(int len, TRAPS);
378
379 // interfaces
380 Array<InstanceKlass*>* local_interfaces() const { return _local_interfaces; }
381 void set_local_interfaces(Array<InstanceKlass*>* a) {
382 guarantee(_local_interfaces == nullptr || a == nullptr, "Just checking");
383 _local_interfaces = a; }
384
385 Array<InstanceKlass*>* transitive_interfaces() const { return _transitive_interfaces; }
386 void set_transitive_interfaces(Array<InstanceKlass*>* a) {
387 guarantee(_transitive_interfaces == nullptr || a == nullptr, "Just checking");
388 _transitive_interfaces = a;
389 }
390
391 private:
392 friend class fieldDescriptor;
393 FieldInfo field(int index) const;
394
395 public:
396 int field_offset (int index) const { return field(index).offset(); }
397 int field_access_flags(int index) const { return field(index).access_flags().as_int(); }
398 FieldInfo::FieldFlags field_flags(int index) const { return field(index).field_flags(); }
399 FieldStatus field_status(int index) const { return fields_status()->at(index); }
400 inline Symbol* field_name (int index) const;
401 inline Symbol* field_signature (int index) const;
402
403 // Number of Java declared fields
404 int java_fields_count() const;
405 int total_fields_count() const;
406
407 Array<u1>* fieldinfo_stream() const { return _fieldinfo_stream; }
408 void set_fieldinfo_stream(Array<u1>* fis) { _fieldinfo_stream = fis; }
409
410 Array<FieldStatus>* fields_status() const {return _fields_status; }
411 void set_fields_status(Array<FieldStatus>* array) { _fields_status = array; }
412
413 // inner classes
414 Array<u2>* inner_classes() const { return _inner_classes; }
415 void set_inner_classes(Array<u2>* f) { _inner_classes = f; }
416
417 // nest members
418 Array<u2>* nest_members() const { return _nest_members; }
419 void set_nest_members(Array<u2>* m) { _nest_members = m; }
420
421 // nest-host index
422 jushort nest_host_index() const { return _nest_host_index; }
423 void set_nest_host_index(u2 i) { _nest_host_index = i; }
424 // dynamic nest member support
425 void set_nest_host(InstanceKlass* host);
426
427 // record components
428 Array<RecordComponent*>* record_components() const { return _record_components; }
429 void set_record_components(Array<RecordComponent*>* record_components) {
430 _record_components = record_components;
431 }
432 bool is_record() const;
433
434 // permitted subclasses
435 Array<u2>* permitted_subclasses() const { return _permitted_subclasses; }
436 void set_permitted_subclasses(Array<u2>* s) { _permitted_subclasses = s; }
437
438 private:
439 // Called to verify that k is a member of this nest - does not look at k's nest-host,
440 // nor does it resolve any CP entries or load any classes.
441 bool has_nest_member(JavaThread* current, InstanceKlass* k) const;
442
443 public:
444 // Call this only if you know that the nest host has been initialized.
445 InstanceKlass* nest_host_not_null() {
446 assert(_nest_host != nullptr, "must be");
447 return _nest_host;
448 }
449 // Used to construct informative IllegalAccessError messages at a higher level,
450 // if there was an issue resolving or validating the nest host.
451 // Returns null if there was no error.
452 const char* nest_host_error();
453 // Returns nest-host class, resolving and validating it if needed.
454 // Returns null if resolution is not possible from the calling context.
455 InstanceKlass* nest_host(TRAPS);
456 // Check if this klass is a nestmate of k - resolves this nest-host and k's
457 bool has_nestmate_access_to(InstanceKlass* k, TRAPS);
458
459 // Called to verify that k is a permitted subclass of this class
460 bool has_as_permitted_subclass(const InstanceKlass* k) const;
461
462 enum InnerClassAttributeOffset {
463 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
464 inner_class_inner_class_info_offset = 0,
465 inner_class_outer_class_info_offset = 1,
466 inner_class_inner_name_offset = 2,
467 inner_class_access_flags_offset = 3,
468 inner_class_next_offset = 4
469 };
470
471 enum EnclosingMethodAttributeOffset {
472 enclosing_method_class_index_offset = 0,
473 enclosing_method_method_index_offset = 1,
474 enclosing_method_attribute_size = 2
475 };
476
477 // package
478 PackageEntry* package() const { return _package_entry; }
479 ModuleEntry* module() const;
480 bool in_unnamed_package() const { return (_package_entry == nullptr); }
481 void set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS);
482 // If the package for the InstanceKlass is in the boot loader's package entry
483 // table then sets the classpath_index field so that
484 // get_system_package() will know to return a non-null value for the
485 // package's location. And, so that the package will be added to the list of
486 // packages returned by get_system_packages().
487 // For packages whose classes are loaded from the boot loader class path, the
488 // classpath_index indicates which entry on the boot loader class path.
489 void set_classpath_index(s2 path_index);
490 bool is_same_class_package(const Klass* class2) const;
491 bool is_same_class_package(oop other_class_loader, const Symbol* other_class_name) const;
492
493 // find an enclosing class
494 InstanceKlass* compute_enclosing_class(bool* inner_is_member, TRAPS) const;
495
496 // Find InnerClasses attribute and return outer_class_info_index & inner_name_index.
497 bool find_inner_classes_attr(int* ooff, int* noff, TRAPS) const;
498
499 private:
500 // Check prohibited package ("java/" only loadable by boot or platform loaders)
501 static void check_prohibited_package(Symbol* class_name,
502 ClassLoaderData* loader_data,
503 TRAPS);
504
505 JavaThread* init_thread() { return Atomic::load(&_init_thread); }
506 const char* init_thread_name() {
507 return init_thread()->name_raw();
508 }
509
510 public:
511 // initialization state
512 bool is_loaded() const { return _init_state >= loaded; }
513 bool is_linked() const { return _init_state >= linked; }
514 bool is_initialized() const { return _init_state == fully_initialized; }
515 bool is_not_initialized() const { return _init_state < being_initialized; }
516 bool is_being_initialized() const { return _init_state == being_initialized; }
517 bool is_in_error_state() const { return _init_state == initialization_error; }
518 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; }
519 ClassState init_state() const { return _init_state; }
520 const char* init_state_name() const;
521 bool is_rewritten() const { return _misc_flags.rewritten(); }
522
523 static const char* state2name(ClassState state);
524
525 // is this a sealed class
526 bool is_sealed() const;
527
528 // defineClass specified verification
529 bool should_verify_class() const { return _misc_flags.should_verify_class(); }
530 void set_should_verify_class(bool value) { _misc_flags.set_should_verify_class(value); }
531
532 // marking
533 bool is_marked_dependent() const { return _misc_flags.is_marked_dependent(); }
534 void set_is_marked_dependent(bool value) { _misc_flags.set_is_marked_dependent(value); }
535
536 // initialization (virtuals from Klass)
537 bool should_be_initialized() const; // means that initialize should be called
538 void initialize_from_cds(TRAPS);
539 void initialize(TRAPS);
540 void link_class(TRAPS);
541 bool link_class_or_fail(TRAPS); // returns false on failure
542 void rewrite_class(TRAPS);
543 void link_methods(TRAPS);
544 Method* class_initializer() const;
545
546 // reference type
547 ReferenceType reference_type() const { return (ReferenceType)_reference_type; }
548
549 // this class cp index
550 u2 this_class_index() const { return _this_class_index; }
551 void set_this_class_index(u2 index) { _this_class_index = index; }
552
553 static ByteSize reference_type_offset() { return byte_offset_of(InstanceKlass, _reference_type); }
554
555 // find local field, returns true if found
556 bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
557 // find field in direct superinterfaces, returns the interface in which the field is defined
558 Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
559 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
560 Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
561 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
562 Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
563
564 // find a non-static or static field given its offset within the class.
565 bool contains_field_offset(int offset);
566
567 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
568 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
569
570 private:
571 inline static int quick_search(const Array<Method*>* methods, const Symbol* name);
572
573 public:
574 static void disable_method_binary_search() {
575 _disable_method_binary_search = true;
576 }
577
578 // find a local method (returns null if not found)
579 Method* find_method(const Symbol* name, const Symbol* signature) const;
580 static Method* find_method(const Array<Method*>* methods,
581 const Symbol* name,
582 const Symbol* signature);
583
584 // find a local method, but skip static methods
585 Method* find_instance_method(const Symbol* name, const Symbol* signature,
586 PrivateLookupMode private_mode) const;
587 static Method* find_instance_method(const Array<Method*>* methods,
588 const Symbol* name,
589 const Symbol* signature,
590 PrivateLookupMode private_mode);
591
592 // find a local method (returns null if not found)
593 Method* find_local_method(const Symbol* name,
594 const Symbol* signature,
595 OverpassLookupMode overpass_mode,
596 StaticLookupMode static_mode,
597 PrivateLookupMode private_mode) const;
598
599 // find a local method from given methods array (returns null if not found)
600 static Method* find_local_method(const Array<Method*>* methods,
601 const Symbol* name,
602 const Symbol* signature,
603 OverpassLookupMode overpass_mode,
604 StaticLookupMode static_mode,
605 PrivateLookupMode private_mode);
606
607 // find a local method index in methods or default_methods (returns -1 if not found)
608 static int find_method_index(const Array<Method*>* methods,
609 const Symbol* name,
610 const Symbol* signature,
611 OverpassLookupMode overpass_mode,
612 StaticLookupMode static_mode,
613 PrivateLookupMode private_mode);
614
615 // lookup operation (returns null if not found)
616 Method* uncached_lookup_method(const Symbol* name,
617 const Symbol* signature,
618 OverpassLookupMode overpass_mode,
619 PrivateLookupMode private_mode = PrivateLookupMode::find) const;
620
621 // lookup a method in all the interfaces that this class implements
622 // (returns null if not found)
623 Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature, DefaultsLookupMode defaults_mode) const;
624
625 // lookup a method in local defaults then in all interfaces
626 // (returns null if not found)
627 Method* lookup_method_in_ordered_interfaces(Symbol* name, Symbol* signature) const;
628
629 // Find method indices by name. If a method with the specified name is
630 // found the index to the first method is returned, and 'end' is filled in
631 // with the index of first non-name-matching method. If no method is found
632 // -1 is returned.
633 int find_method_by_name(const Symbol* name, int* end) const;
634 static int find_method_by_name(const Array<Method*>* methods,
635 const Symbol* name, int* end);
636
637 // constant pool
638 ConstantPool* constants() const { return _constants; }
639 void set_constants(ConstantPool* c) { _constants = c; }
640
641 // protection domain
642 oop protection_domain() const;
643
644 // signers
645 objArrayOop signers() const;
646
647 bool is_contended() const { return _misc_flags.is_contended(); }
648 void set_is_contended(bool value) { _misc_flags.set_is_contended(value); }
649
650 // source file name
651 Symbol* source_file_name() const;
652 u2 source_file_name_index() const;
653 void set_source_file_name_index(u2 sourcefile_index);
654
655 // minor and major version numbers of class file
656 u2 minor_version() const;
657 void set_minor_version(u2 minor_version);
658 u2 major_version() const;
659 void set_major_version(u2 major_version);
660
661 // source debug extension
662 const char* source_debug_extension() const { return _source_debug_extension; }
663 void set_source_debug_extension(const char* array, int length);
664
665 // nonstatic oop-map blocks
666 static int nonstatic_oop_map_size(unsigned int oop_map_count) {
667 return oop_map_count * OopMapBlock::size_in_words();
668 }
669 unsigned int nonstatic_oop_map_count() const {
670 return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
671 }
672 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
673 void set_nonstatic_oop_map_size(int words) {
674 _nonstatic_oop_map_size = words;
675 }
676
677 bool has_contended_annotations() const { return _misc_flags.has_contended_annotations(); }
678 void set_has_contended_annotations(bool value) { _misc_flags.set_has_contended_annotations(value); }
679
680 #if INCLUDE_JVMTI
681 // Redefinition locking. Class can only be redefined by one thread at a time.
682 // The flag is in access_flags so that it can be set and reset using atomic
683 // operations, and not be reset by other misc_flag settings.
684 bool is_being_redefined() const { return _misc_flags.is_being_redefined(); }
685 void set_is_being_redefined(bool value) { _misc_flags.set_is_being_redefined(value); }
686
687 // RedefineClasses() support for previous versions:
688 void add_previous_version(InstanceKlass* ik, int emcp_method_count);
689 void purge_previous_version_list();
690
691 InstanceKlass* previous_versions() const { return _previous_versions; }
692 #else
693 InstanceKlass* previous_versions() const { return nullptr; }
694 #endif
695
696 InstanceKlass* get_klass_version(int version);
697
698 bool has_been_redefined() const { return _misc_flags.has_been_redefined(); }
699 void set_has_been_redefined() { _misc_flags.set_has_been_redefined(true); }
700
701 bool is_scratch_class() const { return _misc_flags.is_scratch_class(); }
702 void set_is_scratch_class() { _misc_flags.set_is_scratch_class(true); }
703
704 bool has_resolved_methods() const { return _misc_flags.has_resolved_methods(); }
705 void set_has_resolved_methods() { _misc_flags.set_has_resolved_methods(true); }
706 void set_has_resolved_methods(bool value) { _misc_flags.set_has_resolved_methods(value); }
707
708 public:
709 #if INCLUDE_JVMTI
710
711 void init_previous_versions() {
712 _previous_versions = nullptr;
713 }
714
715 private:
716 static bool _should_clean_previous_versions;
717 public:
718 static void purge_previous_versions(InstanceKlass* ik) {
719 if (ik->has_been_redefined()) {
720 ik->purge_previous_version_list();
721 }
722 }
723
724 static bool should_clean_previous_versions_and_reset();
725 static bool should_clean_previous_versions() { return _should_clean_previous_versions; }
726
727 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
728 void set_cached_class_file(JvmtiCachedClassFileData *data) {
729 _cached_class_file = data;
730 }
731 JvmtiCachedClassFileData * get_cached_class_file();
732 jint get_cached_class_file_len();
733 unsigned char * get_cached_class_file_bytes();
734
735 // JVMTI: Support for caching of field indices, types, and offsets
736 void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
737 _jvmti_cached_class_field_map = descriptor;
738 }
739 JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
740 return _jvmti_cached_class_field_map;
741 }
742 #else // INCLUDE_JVMTI
743
744 static void purge_previous_versions(InstanceKlass* ik) { return; };
745 static bool should_clean_previous_versions_and_reset() { return false; }
746
747 void set_cached_class_file(JvmtiCachedClassFileData *data) {
748 assert(data == nullptr, "unexpected call with JVMTI disabled");
749 }
750 JvmtiCachedClassFileData * get_cached_class_file() { return (JvmtiCachedClassFileData *)nullptr; }
751
752 #endif // INCLUDE_JVMTI
753
754 bool has_nonstatic_concrete_methods() const { return _misc_flags.has_nonstatic_concrete_methods(); }
755 void set_has_nonstatic_concrete_methods(bool b) { _misc_flags.set_has_nonstatic_concrete_methods(b); }
756
757 bool declares_nonstatic_concrete_methods() const { return _misc_flags.declares_nonstatic_concrete_methods(); }
758 void set_declares_nonstatic_concrete_methods(bool b) { _misc_flags.set_declares_nonstatic_concrete_methods(b); }
759
760 bool has_miranda_methods () const { return _misc_flags.has_miranda_methods(); }
761 void set_has_miranda_methods() { _misc_flags.set_has_miranda_methods(true); }
762 bool has_final_method() const { return _misc_flags.has_final_method(); }
763 void set_has_final_method() { _misc_flags.set_has_final_method(true); }
764
765 // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
766 inline u2 next_method_idnum();
767 void set_initial_method_idnum(u2 value) { _idnum_allocated_count = value; }
768
769 // generics support
770 Symbol* generic_signature() const;
771 u2 generic_signature_index() const;
772 void set_generic_signature_index(u2 sig_index);
773
774 u2 enclosing_method_data(int offset) const;
775 u2 enclosing_method_class_index() const {
776 return enclosing_method_data(enclosing_method_class_index_offset);
777 }
778 u2 enclosing_method_method_index() {
779 return enclosing_method_data(enclosing_method_method_index_offset);
780 }
781 void set_enclosing_method_indices(u2 class_index,
782 u2 method_index);
783
784 // jmethodID support
785 jmethodID get_jmethod_id(const methodHandle& method_h);
786 void ensure_space_for_methodids(int start_offset = 0);
787 jmethodID jmethod_id_or_null(Method* method);
788 void update_methods_jmethod_cache();
789
790 // annotations support
791 Annotations* annotations() const { return _annotations; }
792 void set_annotations(Annotations* anno) { _annotations = anno; }
793
794 AnnotationArray* class_annotations() const {
795 return (_annotations != nullptr) ? _annotations->class_annotations() : nullptr;
796 }
797 Array<AnnotationArray*>* fields_annotations() const {
798 return (_annotations != nullptr) ? _annotations->fields_annotations() : nullptr;
799 }
800 AnnotationArray* class_type_annotations() const {
801 return (_annotations != nullptr) ? _annotations->class_type_annotations() : nullptr;
802 }
803 Array<AnnotationArray*>* fields_type_annotations() const {
804 return (_annotations != nullptr) ? _annotations->fields_type_annotations() : nullptr;
805 }
806 // allocation
807 instanceOop allocate_instance(TRAPS);
808 static instanceOop allocate_instance(oop cls, const char* who, TRAPS);
809
810 // additional member function to return a handle
811 instanceHandle allocate_instance_handle(TRAPS);
812
813 objArrayOop allocate_objArray(int n, int length, TRAPS);
814 // Helper function
815 static instanceOop register_finalizer(instanceOop i, TRAPS);
816
817 // Check whether reflection/jni/jvm code is allowed to instantiate this class;
818 // if not, throw either an Error or an Exception.
819 virtual void check_valid_for_instantiation(bool throwError, TRAPS);
820
821 // initialization
822 void call_class_initializer(TRAPS);
823 void set_initialization_state_and_notify(ClassState state, TRAPS);
824
825 // OopMapCache support
826 OopMapCache* oop_map_cache() { return _oop_map_cache; }
827 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
828 void mask_for(const methodHandle& method, int bci, InterpreterOopMap* entry);
829
830 // JNI identifier support (for static fields - for jni performance)
831 JNIid* jni_ids() { return _jni_ids; }
832 void set_jni_ids(JNIid* ids) { _jni_ids = ids; }
833 JNIid* jni_id_for(int offset);
834
835 public:
836 // maintenance of deoptimization dependencies
837 inline DependencyContext dependencies();
838 void mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes);
839 void add_dependent_nmethod(nmethod* nm);
840 void clean_dependency_context();
841 // Setup link to hierarchy and deoptimize
842 void add_to_hierarchy(JavaThread* current);
843
844 // On-stack replacement support
845 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; };
846 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; };
847 void add_osr_nmethod(nmethod* n);
848 bool remove_osr_nmethod(nmethod* n);
849 int mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m);
850 nmethod* lookup_osr_nmethod(const Method* m, int bci, int level, bool match_level) const;
851
852 #if INCLUDE_JVMTI
853 // Breakpoint support (see methods on Method* for details)
854 BreakpointInfo* breakpoints() const { return _breakpoints; };
855 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
856 #endif
857
858 // support for stub routines
859 static ByteSize init_state_offset() { return byte_offset_of(InstanceKlass, _init_state); }
860 JFR_ONLY(DEFINE_KLASS_TRACE_ID_OFFSET;)
861 static ByteSize init_thread_offset() { return byte_offset_of(InstanceKlass, _init_thread); }
862
863 // subclass/subinterface checks
864 bool implements_interface(Klass* k) const;
865 bool is_same_or_direct_interface(Klass* k) const;
866
867 #ifdef ASSERT
868 // check whether this class or one of its superclasses was redefined
869 bool has_redefined_this_or_super() const;
870 #endif
871
872 // Access to the implementor of an interface.
873 InstanceKlass* implementor() const;
874 void set_implementor(InstanceKlass* ik);
875 int nof_implementors() const;
876 void add_implementor(InstanceKlass* ik); // ik is a new class that implements this interface
877 void init_implementor(); // initialize
878
879 private:
880 // link this class into the implementors list of every interface it implements
881 void process_interfaces();
882
883 public:
884 // virtual operations from Klass
885 GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots,
886 Array<InstanceKlass*>* transitive_interfaces);
887 bool can_be_primary_super_slow() const;
888 size_t oop_size(oop obj) const { return size_helper(); }
889 // slow because it's a virtual call and used for verifying the layout_helper.
890 // Using the layout_helper bits, we can call is_instance_klass without a virtual call.
891 DEBUG_ONLY(bool is_instance_klass_slow() const { return true; })
892
893 // Iterators
894 void do_local_static_fields(FieldClosure* cl);
895 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
896 void do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle, TRAPS);
897 void print_nonstatic_fields(FieldClosure* cl); // including inherited and injected fields
898
899 void methods_do(void f(Method* method));
900
901 static InstanceKlass* cast(Klass* k) {
902 return const_cast<InstanceKlass*>(cast(const_cast<const Klass*>(k)));
903 }
904
905 static const InstanceKlass* cast(const Klass* k) {
906 assert(k != nullptr, "k should not be null");
907 assert(k->is_instance_klass(), "cast to InstanceKlass");
908 return static_cast<const InstanceKlass*>(k);
909 }
910
911 virtual InstanceKlass* java_super() const {
912 return (super() == nullptr) ? nullptr : cast(super());
913 }
914
915 // Sizing (in words)
916 static int header_size() { return sizeof(InstanceKlass)/wordSize; }
917
918 static int size(int vtable_length, int itable_length,
919 int nonstatic_oop_map_size,
920 bool is_interface) {
921 return align_metadata_size(header_size() +
922 vtable_length +
923 itable_length +
924 nonstatic_oop_map_size +
925 (is_interface ? (int)sizeof(Klass*)/wordSize : 0));
926 }
927
928 int size() const { return size(vtable_length(),
929 itable_length(),
930 nonstatic_oop_map_size(),
931 is_interface());
932 }
933
934
935 inline intptr_t* start_of_itable() const;
936 inline intptr_t* end_of_itable() const;
937 inline oop static_field_base_raw();
938
939 inline OopMapBlock* start_of_nonstatic_oop_maps() const;
940 inline Klass** end_of_nonstatic_oop_maps() const;
941
942 inline InstanceKlass* volatile* adr_implementor() const;
943
944 // Use this to return the size of an instance in heap words:
945 int size_helper() const {
946 return layout_helper_to_size_helper(layout_helper());
947 }
948
949 // This bit is initialized in classFileParser.cpp.
950 // It is false under any of the following conditions:
951 // - the class is abstract (including any interface)
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 itable
959 klassItable itable() const; // return klassItable wrapper
960 Method* method_at_itable(InstanceKlass* holder, int index, TRAPS);
961 Method* method_at_itable_or_null(InstanceKlass* holder, int index, bool& itable_entry_found);
962 int vtable_index_of_interface_method(Method* method);
963
964 #if INCLUDE_JVMTI
965 void adjust_default_methods(bool* trace_name_printed);
966 #endif // INCLUDE_JVMTI
967
968 void clean_weak_instanceklass_links();
969 private:
970 void clean_implementors_list();
971 void clean_method_data();
972
973 public:
974 // Explicit metaspace deallocation of fields
975 // For RedefineClasses and class file parsing errors, we need to deallocate
976 // instanceKlasses and the metadata they point to.
977 void deallocate_contents(ClassLoaderData* loader_data);
978 static void deallocate_methods(ClassLoaderData* loader_data,
979 Array<Method*>* methods);
980 void static deallocate_interfaces(ClassLoaderData* loader_data,
981 const Klass* super_klass,
982 Array<InstanceKlass*>* local_interfaces,
983 Array<InstanceKlass*>* transitive_interfaces);
984 void static deallocate_record_components(ClassLoaderData* loader_data,
985 Array<RecordComponent*>* record_component);
986
987 virtual bool on_stack() const;
988
989 // callbacks for actions during class unloading
990 static void unload_class(InstanceKlass* ik);
991
992 virtual void release_C_heap_structures(bool release_sub_metadata = true);
993
994 // Naming
995 const char* signature_name() const;
996
997 // Oop fields (and metadata) iterators
998 //
999 // The InstanceKlass iterators also visits the Object's klass.
1000
1001 // Forward iteration
1002 public:
1003 // Iterate over all oop fields in the oop maps.
1004 template <typename T, class OopClosureType>
1005 inline void oop_oop_iterate_oop_maps(oop obj, OopClosureType* closure);
1006
1007 // Iterate over all oop fields and metadata.
1008 template <typename T, class OopClosureType>
1009 inline void oop_oop_iterate(oop obj, OopClosureType* closure);
1010
1011 // Iterate over all oop fields in one oop map.
1012 template <typename T, class OopClosureType>
1013 inline void oop_oop_iterate_oop_map(OopMapBlock* map, oop obj, OopClosureType* closure);
1014
1015
1016 // Reverse iteration
1017 // Iterate over all oop fields and metadata.
1018 template <typename T, class OopClosureType>
1019 inline void oop_oop_iterate_reverse(oop obj, OopClosureType* closure);
1020
1021 private:
1022 // Iterate over all oop fields in the oop maps.
1023 template <typename T, class OopClosureType>
1024 inline void oop_oop_iterate_oop_maps_reverse(oop obj, OopClosureType* closure);
1025
1026 // Iterate over all oop fields in one oop map.
1027 template <typename T, class OopClosureType>
1028 inline void oop_oop_iterate_oop_map_reverse(OopMapBlock* map, oop obj, OopClosureType* closure);
1029
1030
1031 // Bounded range iteration
1032 public:
1033 // Iterate over all oop fields in the oop maps.
1034 template <typename T, class OopClosureType>
1035 inline void oop_oop_iterate_oop_maps_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1036
1037 // Iterate over all oop fields and metadata.
1038 template <typename T, class OopClosureType>
1039 inline void oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1040
1041 private:
1042 // Iterate over all oop fields in one oop map.
1043 template <typename T, class OopClosureType>
1044 inline void oop_oop_iterate_oop_map_bounded(OopMapBlock* map, oop obj, OopClosureType* closure, MemRegion mr);
1045
1046
1047 public:
1048 u2 idnum_allocated_count() const { return _idnum_allocated_count; }
1049
1050 private:
1051 // initialization state
1052 void set_init_state(ClassState state);
1053 void set_rewritten() { _misc_flags.set_rewritten(true); }
1054 void set_init_thread(JavaThread *thread) {
1055 assert((thread == JavaThread::current() && _init_thread == nullptr) ||
1056 (thread == nullptr && _init_thread == JavaThread::current()), "Only one thread is allowed to own initialization");
1057 Atomic::store(&_init_thread, thread);
1058 }
1059
1060 inline jmethodID* methods_jmethod_ids_acquire() const;
1061 inline void release_set_methods_jmethod_ids(jmethodID* jmeths);
1062 // This nulls out jmethodIDs for all methods in 'klass'
1063 static void clear_jmethod_ids(InstanceKlass* klass);
1064 jmethodID update_jmethod_id(jmethodID* jmeths, Method* method, int idnum);
1065
1066 public:
1067 // Lock for (1) initialization; (2) access to the ConstantPool of this class.
1068 // Must be one per class and it has to be a VM internal object so java code
1069 // cannot lock it (like the mirror).
1070 // It has to be an object not a Mutex because it's held through java calls.
1071 oop init_lock() const;
1072
1073 // Returns the array class for the n'th dimension
1074 virtual ArrayKlass* array_klass(int n, TRAPS);
1075 virtual ArrayKlass* array_klass_or_null(int n);
1076
1077 // Returns the array class with this class as element type
1078 virtual ArrayKlass* array_klass(TRAPS);
1079 virtual ArrayKlass* array_klass_or_null();
1080
1081 static void clean_initialization_error_table();
1082 private:
1083 void fence_and_clear_init_lock();
1084
1085 bool link_class_impl (TRAPS);
1086 bool verify_code (TRAPS);
1087 void initialize_impl (TRAPS);
1088 void initialize_super_interfaces(TRAPS);
1089
1090 void add_initialization_error(JavaThread* current, Handle exception);
1091 oop get_initialization_error(JavaThread* current);
1092
1093 // find a local method (returns null if not found)
1094 Method* find_method_impl(const Symbol* name,
1095 const Symbol* signature,
1096 OverpassLookupMode overpass_mode,
1097 StaticLookupMode static_mode,
1098 PrivateLookupMode private_mode) const;
1099
1100 static Method* find_method_impl(const Array<Method*>* methods,
1101 const Symbol* name,
1102 const Symbol* signature,
1103 OverpassLookupMode overpass_mode,
1104 StaticLookupMode static_mode,
1105 PrivateLookupMode private_mode);
1106
1107 #if INCLUDE_JVMTI
1108 // RedefineClasses support
1109 void link_previous_versions(InstanceKlass* pv) { _previous_versions = pv; }
1110 void mark_newly_obsolete_methods(Array<Method*>* old_methods, int emcp_method_count);
1111 #endif
1112 // log class name to classlist
1113 void log_to_classlist() const;
1114 public:
1115
1116 #if INCLUDE_CDS
1117 // CDS support - remove and restore oops from metadata. Oops are not shared.
1118 virtual void remove_unshareable_info();
1119 void remove_unshareable_flags();
1120 virtual void remove_java_mirror();
1121 void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, PackageEntry* pkg_entry, TRAPS);
1122 void init_shared_package_entry();
1123 bool can_be_verified_at_dumptime() const;
1124 bool methods_contain_jsr_bytecode() const;
1125 void compute_has_loops_flag_for_methods();
1126 #endif
1127
1128 bool has_init_deps_processed() const { return _misc_flags.has_init_deps_processed(); }
1129 void set_has_init_deps_processed() {
1130 assert(is_initialized(), "");
1131 assert(!has_init_deps_processed(), "already set"); // one-off action
1132 _misc_flags.set_has_init_deps_processed(true);
1133 }
1134
1135 jint compute_modifier_flags() const;
1136
1137 public:
1138 // JVMTI support
1139 jint jvmti_class_status() const;
1140
1141 virtual void metaspace_pointers_do(MetaspaceClosure* iter);
1142
1143 public:
1144 // Printing
1145 void print_on(outputStream* st) const;
1146 void print_value_on(outputStream* st) const;
1147
1148 void oop_print_value_on(oop obj, outputStream* st);
1149
1150 void oop_print_on (oop obj, outputStream* st);
1151
1152 #ifndef PRODUCT
1153 void print_dependent_nmethods(bool verbose = false);
1154 bool is_dependent_nmethod(nmethod* nm);
1155 bool verify_itable_index(int index);
1156 #endif
1157
1158 const char* internal_name() const;
1159
1160 // Verification
1161 void verify_on(outputStream* st);
1162
1163 void oop_verify_on(oop obj, outputStream* st);
1164
1165 // Logging
1166 void print_class_load_logging(ClassLoaderData* loader_data,
1167 const ModuleEntry* module_entry,
1168 const ClassFileStream* cfs) const;
1169 private:
1170 void print_class_load_cause_logging() const;
1171 void print_class_load_helper(ClassLoaderData* loader_data,
1172 const ModuleEntry* module_entry,
1173 const ClassFileStream* cfs) const;
1174 };
1175
1176 // for adding methods
1177 // UNSET_IDNUM return means no more ids available
1178 inline u2 InstanceKlass::next_method_idnum() {
1179 if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1180 return ConstMethod::UNSET_IDNUM; // no more ids available
1181 } else {
1182 return _idnum_allocated_count++;
1183 }
1184 }
1185
1186 class PrintClassClosure : public KlassClosure {
1187 private:
1188 outputStream* _st;
1189 bool _verbose;
1190 public:
1191 PrintClassClosure(outputStream* st, bool verbose);
1192
1193 void do_klass(Klass* k);
1194 };
1195
1196 /* JNIid class for jfieldIDs only */
1197 class JNIid: public CHeapObj<mtClass> {
1198 friend class VMStructs;
1199 private:
1200 Klass* _holder;
1201 JNIid* _next;
1202 int _offset;
1203 #ifdef ASSERT
1204 bool _is_static_field_id;
1205 #endif
1206
1207 public:
1208 // Accessors
1209 Klass* holder() const { return _holder; }
1210 int offset() const { return _offset; }
1211 JNIid* next() { return _next; }
1212 // Constructor
1213 JNIid(Klass* holder, int offset, JNIid* next);
1214 // Identifier lookup
1215 JNIid* find(int offset);
1216
1217 bool find_local_field(fieldDescriptor* fd) {
1218 return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1219 }
1220
1221 static void deallocate(JNIid* id);
1222 // Debugging
1223 #ifdef ASSERT
1224 bool is_static_field_id() const { return _is_static_field_id; }
1225 void set_is_static_field_id() { _is_static_field_id = true; }
1226 #endif
1227 void verify(Klass* holder);
1228 };
1229
1230 // An iterator that's used to access the inner classes indices in the
1231 // InstanceKlass::_inner_classes array.
1232 class InnerClassesIterator : public StackObj {
1233 private:
1234 Array<jushort>* _inner_classes;
1235 int _length;
1236 int _idx;
1237 public:
1238
1239 InnerClassesIterator(const InstanceKlass* k) {
1240 _inner_classes = k->inner_classes();
1241 if (k->inner_classes() != nullptr) {
1242 _length = _inner_classes->length();
1243 // The inner class array's length should be the multiple of
1244 // inner_class_next_offset if it only contains the InnerClasses
1245 // attribute data, or it should be
1246 // n*inner_class_next_offset+enclosing_method_attribute_size
1247 // if it also contains the EnclosingMethod data.
1248 assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1249 _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1250 "just checking");
1251 // Remove the enclosing_method portion if exists.
1252 if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1253 _length -= InstanceKlass::enclosing_method_attribute_size;
1254 }
1255 } else {
1256 _length = 0;
1257 }
1258 _idx = 0;
1259 }
1260
1261 int length() const {
1262 return _length;
1263 }
1264
1265 void next() {
1266 _idx += InstanceKlass::inner_class_next_offset;
1267 }
1268
1269 bool done() const {
1270 return (_idx >= _length);
1271 }
1272
1273 u2 inner_class_info_index() const {
1274 return _inner_classes->at(
1275 _idx + InstanceKlass::inner_class_inner_class_info_offset);
1276 }
1277
1278 void set_inner_class_info_index(u2 index) {
1279 _inner_classes->at_put(
1280 _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1281 }
1282
1283 u2 outer_class_info_index() const {
1284 return _inner_classes->at(
1285 _idx + InstanceKlass::inner_class_outer_class_info_offset);
1286 }
1287
1288 void set_outer_class_info_index(u2 index) {
1289 _inner_classes->at_put(
1290 _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1291 }
1292
1293 u2 inner_name_index() const {
1294 return _inner_classes->at(
1295 _idx + InstanceKlass::inner_class_inner_name_offset);
1296 }
1297
1298 void set_inner_name_index(u2 index) {
1299 _inner_classes->at_put(
1300 _idx + InstanceKlass::inner_class_inner_name_offset, index);
1301 }
1302
1303 u2 inner_access_flags() const {
1304 return _inner_classes->at(
1305 _idx + InstanceKlass::inner_class_access_flags_offset);
1306 }
1307 };
1308
1309 // Iterator over class hierarchy under a particular class. Implements depth-first pre-order traversal.
1310 // Usage:
1311 // for (ClassHierarchyIterator iter(root_klass); !iter.done(); iter.next()) {
1312 // Klass* k = iter.klass();
1313 // ...
1314 // }
1315 class ClassHierarchyIterator : public StackObj {
1316 private:
1317 InstanceKlass* _root;
1318 Klass* _current;
1319 bool _visit_subclasses;
1320
1321 public:
1322 ClassHierarchyIterator(InstanceKlass* root) : _root(root), _current(root), _visit_subclasses(true) {
1323 assert(_root == _current, "required"); // initial state
1324 }
1325
1326 bool done() {
1327 return (_current == nullptr);
1328 }
1329
1330 // Make a step iterating over the class hierarchy under the root class.
1331 // Skips subclasses if requested.
1332 void next();
1333
1334 Klass* klass() {
1335 assert(!done(), "sanity");
1336 return _current;
1337 }
1338
1339 // Skip subclasses of the current class.
1340 void skip_subclasses() {
1341 _visit_subclasses = false;
1342 }
1343 };
1344
1345 #endif // SHARE_OOPS_INSTANCEKLASS_HPP