1 /*
2 * Copyright (c) 1997, 2025, 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/allocation.hpp"
29 #include "memory/referenceType.hpp"
30 #include "oops/annotations.hpp"
31 #include "oops/constMethod.hpp"
32 #include "oops/fieldInfo.hpp"
33 #include "oops/instanceKlassFlags.hpp"
34 #include "oops/instanceOop.hpp"
35 #include "runtime/handles.hpp"
36 #include "runtime/javaThread.hpp"
37 #include "utilities/accessFlags.hpp"
38 #include "utilities/align.hpp"
39 #include "utilities/growableArray.hpp"
40 #include "utilities/macros.hpp"
41 #if INCLUDE_JFR
42 #include "jfr/support/jfrKlassExtension.hpp"
43 #endif
44
45 class ConstantPool;
46 class DeoptimizationScope;
47 class klassItable;
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 JNIid;
71 class JvmtiCachedClassFieldMap;
72 class nmethodBucket;
73 class OopMapCache;
74 class InterpreterOopMap;
75 class PackageEntry;
76 class ModuleEntry;
77
78 // This is used in iterators below.
79 class FieldClosure: public StackObj {
80 public:
81 virtual void do_field(fieldDescriptor* fd) = 0;
82 };
83
84 // Print fields.
85 // If "obj" argument to constructor is null, prints static fields, otherwise prints non-static fields.
86 class FieldPrinter: public FieldClosure {
87 oop _obj;
88 outputStream* _st;
89 public:
90 FieldPrinter(outputStream* st, oop obj = nullptr) : _obj(obj), _st(st) {}
91 void do_field(fieldDescriptor* fd);
92 };
93
94 // Describes where oops are located in instances of this klass.
95 class OopMapBlock {
96 public:
97 // Byte offset of the first oop mapped by this block.
98 int offset() const { return _offset; }
99 void set_offset(int offset) { _offset = offset; }
100
101 // Number of oops in this block.
102 uint count() const { return _count; }
103 void set_count(uint count) { _count = count; }
104
105 void increment_count(int diff) { _count += diff; }
106
107 int offset_span() const { return _count * heapOopSize; }
108
109 int end_offset() const {
110 return offset() + offset_span();
111 }
112
113 bool is_contiguous(int another_offset) const {
114 return another_offset == end_offset();
115 }
116
117 // sizeof(OopMapBlock) in words.
118 static int size_in_words() {
119 return align_up((int)sizeof(OopMapBlock), wordSize) >>
120 LogBytesPerWord;
121 }
122
123 static int compare_offset(const OopMapBlock* a, const OopMapBlock* b) {
124 return a->offset() - b->offset();
125 }
126
127 private:
128 int _offset;
129 uint _count;
130 };
131
132 struct JvmtiCachedClassFileData;
133
134 class InstanceKlass: public Klass {
135 friend class VMStructs;
136 friend class JVMCIVMStructs;
137 friend class ClassFileParser;
138 friend class CompileReplay;
139
140 public:
141 static const KlassKind Kind = InstanceKlassKind;
142
143 protected:
144 InstanceKlass(const ClassFileParser& parser, KlassKind kind = Kind, ReferenceType reference_type = REF_NONE);
145
146 void* operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, bool use_class_space, TRAPS) throw();
147
148 public:
149 InstanceKlass();
150
151 // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
152 // of the class loading & initialization procedure, and the use of the states.
153 enum ClassState : u1 {
154 allocated, // allocated (but not yet linked)
155 loaded, // loaded and inserted in class hierarchy (but not linked yet)
156 linked, // successfully linked/verified (but not initialized yet)
157 being_initialized, // currently running class initializer
158 fully_initialized, // initialized (successful final state)
159 initialization_error // error happened during initialization
160 };
161
162 private:
163 static InstanceKlass* allocate_instance_klass(const ClassFileParser& parser, TRAPS);
164
165 protected:
166 // If you add a new field that points to any metaspace object, you
167 // must add this field to InstanceKlass::metaspace_pointers_do().
168
169 // Annotations for this class
170 Annotations* _annotations;
171 // Package this class is defined in
172 PackageEntry* _package_entry;
173 // Array classes holding elements of this class.
174 ObjArrayKlass* volatile _array_klasses;
175 // Constant pool for this class.
176 ConstantPool* _constants;
177 // The InnerClasses attribute and EnclosingMethod attribute. The
178 // _inner_classes is an array of shorts. If the class has InnerClasses
179 // attribute, then the _inner_classes array begins with 4-tuples of shorts
180 // [inner_class_info_index, outer_class_info_index,
181 // inner_name_index, inner_class_access_flags] for the InnerClasses
182 // attribute. If the EnclosingMethod attribute exists, it occupies the
183 // last two shorts [class_index, method_index] of the array. If only
184 // the InnerClasses attribute exists, the _inner_classes array length is
185 // number_of_inner_classes * 4. If the class has both InnerClasses
186 // and EnclosingMethod attributes the _inner_classes array length is
187 // number_of_inner_classes * 4 + enclosing_method_attribute_size.
188 Array<jushort>* _inner_classes;
189
190 // The NestMembers attribute. An array of shorts, where each is a
191 // class info index for the class that is a nest member. This data
192 // has not been validated.
193 Array<jushort>* _nest_members;
194
195 // Resolved nest-host klass: either true nest-host or self if we are not
196 // nested, or an error occurred resolving or validating the nominated
197 // nest-host. Can also be set directly by JDK API's that establish nest
198 // relationships.
199 // By always being set it makes nest-member access checks simpler.
200 InstanceKlass* _nest_host;
201
202 // The PermittedSubclasses attribute. An array of shorts, where each is a
203 // class info index for the class that is a permitted subclass.
204 Array<jushort>* _permitted_subclasses;
205
206 // The contents of the Record attribute.
207 Array<RecordComponent*>* _record_components;
208
209 // the source debug extension for this klass, null if not specified.
210 // Specified as UTF-8 string without terminating zero byte in the classfile,
211 // it is stored in the instanceklass as a null-terminated UTF-8 string
212 const char* _source_debug_extension;
213
214 // Number of heapOopSize words used by non-static fields in this klass
215 // (including inherited fields but after header_size()).
216 int _nonstatic_field_size;
217 int _static_field_size; // number words used by static fields (oop and non-oop) in this klass
218 int _nonstatic_oop_map_size; // size in words of nonstatic oop map blocks
219 int _itable_len; // length of Java itable (in words)
220
221 // The NestHost attribute. The class info index for the class
222 // that is the nest-host of this class. This data has not been validated.
223 u2 _nest_host_index;
224 u2 _this_class_index; // constant pool entry
225 u2 _static_oop_field_count; // number of static oop fields in this klass
226
227 volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change
228
229 // Class states are defined as ClassState (see above).
230 // Place the _init_state here to utilize the unused 2-byte after
231 // _idnum_allocated_count.
232 volatile ClassState _init_state; // state of class
233
234 u1 _reference_type; // reference type
235
236 // State is set either at parse time or while executing, atomically to not disturb other state
237 InstanceKlassFlags _misc_flags;
238
239 JavaThread* volatile _init_thread; // Pointer to current thread doing initialization (to handle recursive initialization)
240
241 OopMapCache* volatile _oop_map_cache; // OopMapCache for all methods in the klass (allocated lazily)
242 JNIid* _jni_ids; // First JNI identifier for static fields in this class
243 jmethodID* volatile _methods_jmethod_ids; // jmethodIDs corresponding to method_idnum, or null if none
244 nmethodBucket* volatile _dep_context; // packed DependencyContext structure
245 uint64_t volatile _dep_context_last_cleaned;
246 nmethod* _osr_nmethods_head; // Head of list of on-stack replacement nmethods for this class
247 #if INCLUDE_JVMTI
248 BreakpointInfo* _breakpoints; // bpt lists, managed by Method*
249 // Linked instanceKlasses of previous versions
250 InstanceKlass* _previous_versions;
251 // JVMTI fields can be moved to their own structure - see 6315920
252 // JVMTI: cached class file, before retransformable agent modified it in CFLH
253 JvmtiCachedClassFileData* _cached_class_file;
254 #endif
255
256 #if INCLUDE_JVMTI
257 JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration
258 #endif
259
260 NOT_PRODUCT(int _verify_count;) // to avoid redundant verifies
261 NOT_PRODUCT(volatile int _shared_class_load_count;) // ensure a shared class is loaded only once
262
263 // Method array.
264 Array<Method*>* _methods;
265 // Default Method Array, concrete methods inherited from interfaces
266 Array<Method*>* _default_methods;
267 // Interfaces (InstanceKlass*s) this class declares locally to implement.
268 Array<InstanceKlass*>* _local_interfaces;
269 // Interfaces (InstanceKlass*s) this class implements transitively.
270 Array<InstanceKlass*>* _transitive_interfaces;
271 // Int array containing the original order of method in the class file (for JVMTI).
272 Array<int>* _method_ordering;
273 // Int array containing the vtable_indices for default_methods
274 // offset matches _default_methods offset
275 Array<int>* _default_vtable_indices;
276
277 // Fields information is stored in an UNSIGNED5 encoded stream (see fieldInfo.hpp)
278 Array<u1>* _fieldinfo_stream;
279 Array<FieldStatus>* _fields_status;
280
281 // embedded Java vtable follows here
282 // embedded Java itables follows here
283 // embedded static fields follows here
284 // embedded nonstatic oop-map blocks follows here
285 // embedded implementor of this interface follows here
286 // The embedded implementor only exists if the current klass is an
287 // interface. The possible values of the implementor fall into following
288 // three cases:
289 // null: no implementor.
290 // A Klass* that's not itself: one implementor.
291 // Itself: more than one implementors.
292 //
293
294 friend class SystemDictionary;
295
296 static bool _disable_method_binary_search;
297
298 // Controls finalizer registration
299 static bool _finalization_enabled;
300
301 public:
302
303 // Queries finalization state
304 static bool is_finalization_enabled() { return _finalization_enabled; }
305
306 // Sets finalization state
307 static void set_finalization_enabled(bool val) { _finalization_enabled = val; }
308
309 // The three BUILTIN class loader types
310 bool is_shared_boot_class() const { return _misc_flags.is_shared_boot_class(); }
311 bool is_shared_platform_class() const { return _misc_flags.is_shared_platform_class(); }
312 bool is_shared_app_class() const { return _misc_flags.is_shared_app_class(); }
313 // The UNREGISTERED class loader type
314 bool is_shared_unregistered_class() const { return _misc_flags.is_shared_unregistered_class(); }
315
316 // Check if the class can be shared in CDS
317 bool is_shareable() const;
318
319 bool shared_loading_failed() const { return _misc_flags.shared_loading_failed(); }
320
321 void set_shared_loading_failed() { _misc_flags.set_shared_loading_failed(true); }
322
323 #if INCLUDE_CDS
324 int shared_class_loader_type() const;
325 void set_shared_class_loader_type(s2 loader_type) { _misc_flags.set_shared_class_loader_type(loader_type); }
326 void assign_class_loader_type() { _misc_flags.assign_class_loader_type(_class_loader_data); }
327 #endif
328
329 bool has_nonstatic_fields() const { return _misc_flags.has_nonstatic_fields(); }
330 void set_has_nonstatic_fields(bool b) { _misc_flags.set_has_nonstatic_fields(b); }
331
332 bool has_localvariable_table() const { return _misc_flags.has_localvariable_table(); }
333 void set_has_localvariable_table(bool b) { _misc_flags.set_has_localvariable_table(b); }
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 itable
346 int itable_length() const { return _itable_len; }
347 void set_itable_length(int len) { _itable_len = len; }
348
349 // array klasses
350 ObjArrayKlass* array_klasses() const { return _array_klasses; }
351 inline ObjArrayKlass* array_klasses_acquire() const; // load with acquire semantics
352 inline void release_set_array_klasses(ObjArrayKlass* k); // store with release semantics
353 void set_array_klasses(ObjArrayKlass* k) { _array_klasses = k; }
354
355 // methods
356 Array<Method*>* methods() const { return _methods; }
357 void set_methods(Array<Method*>* a) { _methods = a; }
358 Method* method_with_idnum(int idnum);
359 Method* method_with_orig_idnum(int idnum);
360 Method* method_with_orig_idnum(int idnum, int version);
361
362 // method ordering
363 Array<int>* method_ordering() const { return _method_ordering; }
364 void set_method_ordering(Array<int>* m) { _method_ordering = m; }
365 void copy_method_ordering(const intArray* m, TRAPS);
366
367 // default_methods
368 Array<Method*>* default_methods() const { return _default_methods; }
369 void set_default_methods(Array<Method*>* a) { _default_methods = a; }
370
371 // default method vtable_indices
372 Array<int>* default_vtable_indices() const { return _default_vtable_indices; }
373 void set_default_vtable_indices(Array<int>* v) { _default_vtable_indices = v; }
374 Array<int>* create_new_default_vtable_indices(int len, TRAPS);
375
376 // interfaces
377 Array<InstanceKlass*>* local_interfaces() const { return _local_interfaces; }
378 void set_local_interfaces(Array<InstanceKlass*>* a) {
379 guarantee(_local_interfaces == nullptr || a == nullptr, "Just checking");
380 _local_interfaces = a; }
381
382 Array<InstanceKlass*>* transitive_interfaces() const { return _transitive_interfaces; }
383 void set_transitive_interfaces(Array<InstanceKlass*>* a) {
384 guarantee(_transitive_interfaces == nullptr || a == nullptr, "Just checking");
385 _transitive_interfaces = a;
386 }
387
388 private:
389 friend class fieldDescriptor;
390 FieldInfo field(int index) const;
391
392 public:
393 int field_offset (int index) const { return field(index).offset(); }
394 int field_access_flags(int index) const { return field(index).access_flags().as_field_flags(); }
395 FieldInfo::FieldFlags field_flags(int index) const { return field(index).field_flags(); }
396 FieldStatus field_status(int index) const { return fields_status()->at(index); }
397 inline Symbol* field_name (int index) const;
398 inline Symbol* field_signature (int index) const;
399
400 // Number of Java declared fields
401 int java_fields_count() const;
402 int total_fields_count() const;
403
404 Array<u1>* fieldinfo_stream() const { return _fieldinfo_stream; }
405 void set_fieldinfo_stream(Array<u1>* fis) { _fieldinfo_stream = fis; }
406
407 Array<FieldStatus>* fields_status() const {return _fields_status; }
408 void set_fields_status(Array<FieldStatus>* array) { _fields_status = array; }
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 // nest members
415 Array<u2>* nest_members() const { return _nest_members; }
416 void set_nest_members(Array<u2>* m) { _nest_members = m; }
417
418 // nest-host index
419 jushort nest_host_index() const { return _nest_host_index; }
420 void set_nest_host_index(u2 i) { _nest_host_index = i; }
421 // dynamic nest member support
422 void set_nest_host(InstanceKlass* host);
423
424 // record components
425 Array<RecordComponent*>* record_components() const { return _record_components; }
426 void set_record_components(Array<RecordComponent*>* record_components) {
427 _record_components = record_components;
428 }
429 bool is_record() const;
430
431 // test for enum class (or possibly an anonymous subclass within a sealed enum)
432 bool is_enum_subclass() 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 // The incoming stringStream is used for logging, and for the caller to create
461 // a detailed exception message on failure.
462 bool has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const;
463
464 enum InnerClassAttributeOffset {
465 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
466 inner_class_inner_class_info_offset = 0,
467 inner_class_outer_class_info_offset = 1,
468 inner_class_inner_name_offset = 2,
469 inner_class_access_flags_offset = 3,
470 inner_class_next_offset = 4
471 };
472
473 enum EnclosingMethodAttributeOffset {
474 enclosing_method_class_index_offset = 0,
475 enclosing_method_method_index_offset = 1,
476 enclosing_method_attribute_size = 2
477 };
478
479 // package
480 PackageEntry* package() const { return _package_entry; }
481 ModuleEntry* module() const;
482 bool in_javabase_module() const;
483 bool in_unnamed_package() const { return (_package_entry == nullptr); }
484 void set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS);
485 // If the package for the InstanceKlass is in the boot loader's package entry
486 // table then sets the classpath_index field so that
487 // get_system_package() will know to return a non-null value for the
488 // package's location. And, so that the package will be added to the list of
489 // packages returned by get_system_packages().
490 // For packages whose classes are loaded from the boot loader class path, the
491 // classpath_index indicates which entry on the boot loader class path.
492 void set_classpath_index(s2 path_index);
493 bool is_same_class_package(const Klass* class2) const;
494 bool is_same_class_package(oop other_class_loader, const Symbol* other_class_name) const;
495
496 // find an enclosing class
497 InstanceKlass* compute_enclosing_class(bool* inner_is_member, TRAPS) const;
498
499 // Find InnerClasses attribute and return outer_class_info_index & inner_name_index.
500 bool find_inner_classes_attr(int* ooff, int* noff, TRAPS) const;
501
502 private:
503 // Check prohibited package ("java/" only loadable by boot or platform loaders)
504 static void check_prohibited_package(Symbol* class_name,
505 ClassLoaderData* loader_data,
506 TRAPS);
507
508 JavaThread* init_thread() { return Atomic::load(&_init_thread); }
509 const char* init_thread_name() {
510 return init_thread()->name_raw();
511 }
512
513 public:
514 // initialization state
515 bool is_loaded() const { return init_state() >= loaded; }
516 bool is_linked() const { return init_state() >= linked; }
517 bool is_initialized() const { return init_state() == fully_initialized; }
518 bool is_not_initialized() const { return init_state() < being_initialized; }
519 bool is_being_initialized() const { return init_state() == being_initialized; }
520 bool is_in_error_state() const { return init_state() == initialization_error; }
521 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; }
522 ClassState init_state() const { return Atomic::load_acquire(&_init_state); }
523 const char* init_state_name() const;
524 bool is_rewritten() const { return _misc_flags.rewritten(); }
525
526 // is this a sealed class
527 bool is_sealed() const;
528
529 // defineClass specified verification
530 bool should_verify_class() const { return _misc_flags.should_verify_class(); }
531 void set_should_verify_class(bool value) { _misc_flags.set_should_verify_class(value); }
532
533 // marking
534 bool is_marked_dependent() const { return _misc_flags.is_marked_dependent(); }
535 void set_is_marked_dependent(bool value) { _misc_flags.set_is_marked_dependent(value); }
536
537 // initialization (virtuals from Klass)
538 bool should_be_initialized() const; // means that initialize should be called
539 void initialize_with_aot_initialized_mirror(TRAPS);
540 void assert_no_clinit_will_run_for_aot_initialized_class() const NOT_DEBUG_RETURN;
541 void initialize(TRAPS);
542 void initialize_preemptable(TRAPS);
543 void link_class(TRAPS);
544 bool link_class_or_fail(TRAPS); // returns false on failure
545 void rewrite_class(TRAPS);
546 void link_methods(TRAPS);
547 Method* class_initializer() const;
548 bool interface_needs_clinit_execution_as_super(bool also_check_supers=true) const;
549
550 // reference type
551 ReferenceType reference_type() const { return (ReferenceType)_reference_type; }
552
553 // this class cp index
554 u2 this_class_index() const { return _this_class_index; }
555 void set_this_class_index(u2 index) { _this_class_index = index; }
556
557 static ByteSize reference_type_offset() { return byte_offset_of(InstanceKlass, _reference_type); }
558
559 // find local field, returns true if found
560 bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
561 // find field in direct superinterfaces, returns the interface in which the field is defined
562 Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
563 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
564 Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
565 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
566 Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
567
568 // find a non-static or static field given its offset within the class.
569 bool contains_field_offset(int offset);
570
571 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
572 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
573
574 private:
575 inline static int quick_search(const Array<Method*>* methods, const Symbol* name);
576
577 public:
578 static void disable_method_binary_search() {
579 _disable_method_binary_search = true;
580 }
581
582 // find a local method (returns null if not found)
583 Method* find_method(const Symbol* name, const Symbol* signature) const;
584 static Method* find_method(const Array<Method*>* methods,
585 const Symbol* name,
586 const Symbol* signature);
587
588 // find a local method, but skip static methods
589 Method* find_instance_method(const Symbol* name, const Symbol* signature,
590 PrivateLookupMode private_mode) const;
591 static Method* find_instance_method(const Array<Method*>* methods,
592 const Symbol* name,
593 const Symbol* signature,
594 PrivateLookupMode private_mode);
595
596 // find a local method (returns null if not found)
597 Method* find_local_method(const Symbol* name,
598 const Symbol* signature,
599 OverpassLookupMode overpass_mode,
600 StaticLookupMode static_mode,
601 PrivateLookupMode private_mode) const;
602
603 // find a local method from given methods array (returns null if not found)
604 static Method* find_local_method(const Array<Method*>* methods,
605 const Symbol* name,
606 const Symbol* signature,
607 OverpassLookupMode overpass_mode,
608 StaticLookupMode static_mode,
609 PrivateLookupMode private_mode);
610
611 // find a local method index in methods or default_methods (returns -1 if not found)
612 static int find_method_index(const Array<Method*>* methods,
613 const Symbol* name,
614 const Symbol* signature,
615 OverpassLookupMode overpass_mode,
616 StaticLookupMode static_mode,
617 PrivateLookupMode private_mode);
618
619 // lookup operation (returns null if not found)
620 Method* uncached_lookup_method(const Symbol* name,
621 const Symbol* signature,
622 OverpassLookupMode overpass_mode,
623 PrivateLookupMode private_mode = PrivateLookupMode::find) const;
624
625 // lookup a method in all the interfaces that this class implements
626 // (returns null if not found)
627 Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature, DefaultsLookupMode defaults_mode) const;
628
629 // lookup a method in local defaults then in all interfaces
630 // (returns null if not found)
631 Method* lookup_method_in_ordered_interfaces(Symbol* name, Symbol* signature) const;
632
633 // Find method indices by name. If a method with the specified name is
634 // found the index to the first method is returned, and 'end' is filled in
635 // with the index of first non-name-matching method. If no method is found
636 // -1 is returned.
637 int find_method_by_name(const Symbol* name, int* end) const;
638 static int find_method_by_name(const Array<Method*>* methods,
639 const Symbol* name, int* end);
640
641 // constant pool
642 ConstantPool* constants() const { return _constants; }
643 void set_constants(ConstantPool* c) { _constants = c; }
644
645 // protection domain
646 oop protection_domain() const;
647
648 // signers
649 objArrayOop signers() const;
650
651 bool is_contended() const { return _misc_flags.is_contended(); }
652 void set_is_contended(bool value) { _misc_flags.set_is_contended(value); }
653
654 // source file name
655 Symbol* source_file_name() const;
656 u2 source_file_name_index() const;
657 void set_source_file_name_index(u2 sourcefile_index);
658
659 // minor and major version numbers of class file
660 u2 minor_version() const;
661 void set_minor_version(u2 minor_version);
662 u2 major_version() const;
663 void set_major_version(u2 major_version);
664
665 // source debug extension
666 const char* source_debug_extension() const { return _source_debug_extension; }
667 void set_source_debug_extension(const char* array, int length);
668
669 // nonstatic oop-map blocks
670 static int nonstatic_oop_map_size(unsigned int oop_map_count) {
671 return oop_map_count * OopMapBlock::size_in_words();
672 }
673 unsigned int nonstatic_oop_map_count() const {
674 return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
675 }
676 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
677 void set_nonstatic_oop_map_size(int words) {
678 _nonstatic_oop_map_size = words;
679 }
680
681 bool has_contended_annotations() const { return _misc_flags.has_contended_annotations(); }
682 void set_has_contended_annotations(bool value) { _misc_flags.set_has_contended_annotations(value); }
683
684 #if INCLUDE_JVMTI
685 // Redefinition locking. Class can only be redefined by one thread at a time.
686 bool is_being_redefined() const { return _misc_flags.is_being_redefined(); }
687 void set_is_being_redefined(bool value) { _misc_flags.set_is_being_redefined(value); }
688
689 // RedefineClasses() support for previous versions:
690 void add_previous_version(InstanceKlass* ik, int emcp_method_count);
691 void purge_previous_version_list();
692
693 InstanceKlass* previous_versions() const { return _previous_versions; }
694 #else
695 InstanceKlass* previous_versions() const { return nullptr; }
696 #endif
697
698 InstanceKlass* get_klass_version(int version);
699
700 bool has_been_redefined() const { return _misc_flags.has_been_redefined(); }
701 void set_has_been_redefined() { _misc_flags.set_has_been_redefined(true); }
702
703 bool is_scratch_class() const { return _misc_flags.is_scratch_class(); }
704 void set_is_scratch_class() { _misc_flags.set_is_scratch_class(true); }
705
706 bool has_resolved_methods() const { return _misc_flags.has_resolved_methods(); }
707 void set_has_resolved_methods() { _misc_flags.set_has_resolved_methods(true); }
708 void set_has_resolved_methods(bool value) { _misc_flags.set_has_resolved_methods(value); }
709
710 public:
711 #if INCLUDE_JVMTI
712
713 void init_previous_versions() {
714 _previous_versions = nullptr;
715 }
716
717 private:
718 static bool _should_clean_previous_versions;
719 public:
720 static void purge_previous_versions(InstanceKlass* ik) {
721 if (ik->has_been_redefined()) {
722 ik->purge_previous_version_list();
723 }
724 }
725
726 static bool should_clean_previous_versions_and_reset();
727 static bool should_clean_previous_versions() { return _should_clean_previous_versions; }
728
729 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
730 void set_cached_class_file(JvmtiCachedClassFileData *data) {
731 _cached_class_file = data;
732 }
733 JvmtiCachedClassFileData * get_cached_class_file();
734 jint get_cached_class_file_len();
735 unsigned char * get_cached_class_file_bytes();
736
737 // JVMTI: Support for caching of field indices, types, and offsets
738 void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
739 _jvmti_cached_class_field_map = descriptor;
740 }
741 JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
742 return _jvmti_cached_class_field_map;
743 }
744 #else // INCLUDE_JVMTI
745
746 static void purge_previous_versions(InstanceKlass* ik) { return; };
747 static bool should_clean_previous_versions_and_reset() { return false; }
748
749 void set_cached_class_file(JvmtiCachedClassFileData *data) {
750 assert(data == nullptr, "unexpected call with JVMTI disabled");
751 }
752 JvmtiCachedClassFileData * get_cached_class_file() { return (JvmtiCachedClassFileData *)nullptr; }
753
754 #endif // INCLUDE_JVMTI
755
756 bool has_nonstatic_concrete_methods() const { return _misc_flags.has_nonstatic_concrete_methods(); }
757 void set_has_nonstatic_concrete_methods(bool b) { _misc_flags.set_has_nonstatic_concrete_methods(b); }
758
759 bool declares_nonstatic_concrete_methods() const { return _misc_flags.declares_nonstatic_concrete_methods(); }
760 void set_declares_nonstatic_concrete_methods(bool b) { _misc_flags.set_declares_nonstatic_concrete_methods(b); }
761
762 bool has_miranda_methods () const { return _misc_flags.has_miranda_methods(); }
763 void set_has_miranda_methods() { _misc_flags.set_has_miranda_methods(true); }
764 bool has_final_method() const { return _misc_flags.has_final_method(); }
765 void set_has_final_method() { _misc_flags.set_has_final_method(true); }
766
767 // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
768 inline u2 next_method_idnum();
769 void set_initial_method_idnum(u2 value) { _idnum_allocated_count = value; }
770
771 // generics support
772 Symbol* generic_signature() const;
773 u2 generic_signature_index() const;
774 void set_generic_signature_index(u2 sig_index);
775
776 u2 enclosing_method_data(int offset) const;
777 u2 enclosing_method_class_index() const {
778 return enclosing_method_data(enclosing_method_class_index_offset);
779 }
780 u2 enclosing_method_method_index() {
781 return enclosing_method_data(enclosing_method_method_index_offset);
782 }
783 void set_enclosing_method_indices(u2 class_index,
784 u2 method_index);
785
786 // jmethodID support
787 jmethodID get_jmethod_id(const methodHandle& method_h);
788 void ensure_space_for_methodids(int start_offset = 0);
789 jmethodID jmethod_id_or_null(Method* method);
790 void update_methods_jmethod_cache();
791
792 // annotations support
793 Annotations* annotations() const { return _annotations; }
794 void set_annotations(Annotations* anno) { _annotations = anno; }
795
796 AnnotationArray* class_annotations() const {
797 return (_annotations != nullptr) ? _annotations->class_annotations() : nullptr;
798 }
799 Array<AnnotationArray*>* fields_annotations() const {
800 return (_annotations != nullptr) ? _annotations->fields_annotations() : nullptr;
801 }
802 AnnotationArray* class_type_annotations() const {
803 return (_annotations != nullptr) ? _annotations->class_type_annotations() : nullptr;
804 }
805 Array<AnnotationArray*>* fields_type_annotations() const {
806 return (_annotations != nullptr) ? _annotations->fields_type_annotations() : nullptr;
807 }
808 // allocation
809 instanceOop allocate_instance(TRAPS);
810 static instanceOop allocate_instance(oop cls, TRAPS);
811
812 // additional member function to return a handle
813 instanceHandle allocate_instance_handle(TRAPS);
814
815 objArrayOop allocate_objArray(int n, int length, TRAPS);
816 // Helper function
817 static instanceOop register_finalizer(instanceOop i, TRAPS);
818
819 // Check whether reflection/jni/jvm code is allowed to instantiate this class;
820 // if not, throw either an Error or an Exception.
821 virtual void check_valid_for_instantiation(bool throwError, TRAPS);
822
823 // initialization
824 void call_class_initializer(TRAPS);
825 void set_initialization_state_and_notify(ClassState state, TRAPS);
826
827 // OopMapCache support
828 OopMapCache* oop_map_cache() { return _oop_map_cache; }
829 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
830 void mask_for(const methodHandle& method, int bci, InterpreterOopMap* entry);
831
832 // JNI identifier support (for static fields - for jni performance)
833 JNIid* jni_ids() { return _jni_ids; }
834 void set_jni_ids(JNIid* ids) { _jni_ids = ids; }
835 JNIid* jni_id_for(int offset);
836
837 public:
838 // maintenance of deoptimization dependencies
839 inline DependencyContext dependencies();
840 void mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes);
841 void add_dependent_nmethod(nmethod* nm);
842 void clean_dependency_context();
843 // Setup link to hierarchy and deoptimize
844 void add_to_hierarchy(JavaThread* current);
845
846 // On-stack replacement support
847 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; };
848 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; };
849 void add_osr_nmethod(nmethod* n);
850 bool remove_osr_nmethod(nmethod* n);
851 int mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m);
852 nmethod* lookup_osr_nmethod(const Method* m, int bci, int level, bool match_level) const;
853
854 #if INCLUDE_JVMTI
855 // Breakpoint support (see methods on Method* for details)
856 BreakpointInfo* breakpoints() const { return _breakpoints; };
857 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
858 #endif
859
860 // support for stub routines
861 static ByteSize init_state_offset() { return byte_offset_of(InstanceKlass, _init_state); }
862 JFR_ONLY(DEFINE_KLASS_TRACE_ID_OFFSET;)
863 static ByteSize init_thread_offset() { return byte_offset_of(InstanceKlass, _init_thread); }
864
865 // subclass/subinterface checks
866 bool implements_interface(Klass* k) const;
867 bool is_same_or_direct_interface(Klass* k) const;
868
869 #ifdef ASSERT
870 // check whether this class or one of its superclasses was redefined
871 bool has_redefined_this_or_super() const;
872 #endif
873
874 // Access to the implementor of an interface.
875 InstanceKlass* implementor() const;
876 void set_implementor(InstanceKlass* ik);
877 int nof_implementors() const;
878 void add_implementor(InstanceKlass* ik); // ik is a new class that implements this interface
879 void init_implementor(); // initialize
880
881 private:
882 // link this class into the implementors list of every interface it implements
883 void process_interfaces();
884
885 public:
886 // virtual operations from Klass
887 GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots,
888 Array<InstanceKlass*>* transitive_interfaces);
889 bool can_be_primary_super_slow() const;
890 size_t oop_size(oop obj) const { return size_helper(); }
891 // slow because it's a virtual call and used for verifying the layout_helper.
892 // Using the layout_helper bits, we can call is_instance_klass without a virtual call.
893 DEBUG_ONLY(bool is_instance_klass_slow() const { return true; })
894
895 // Iterators
896 void do_local_static_fields(FieldClosure* cl);
897 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
898 void do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle, TRAPS);
899 void print_nonstatic_fields(FieldClosure* cl); // including inherited and injected fields
900
901 void methods_do(void f(Method* method));
902
903 static InstanceKlass* cast(Klass* k) {
904 return const_cast<InstanceKlass*>(cast(const_cast<const Klass*>(k)));
905 }
906
907 static const InstanceKlass* cast(const Klass* k) {
908 assert(k != nullptr, "k should not be null");
909 assert(k->is_instance_klass(), "cast to InstanceKlass");
910 return static_cast<const InstanceKlass*>(k);
911 }
912
913 virtual InstanceKlass* java_super() const {
914 return (super() == nullptr) ? nullptr : cast(super());
915 }
916
917 // Sizing (in words)
918 static int header_size() { return sizeof(InstanceKlass)/wordSize; }
919
920 static int size(int vtable_length, int itable_length,
921 int nonstatic_oop_map_size,
922 bool is_interface) {
923 return align_metadata_size(header_size() +
924 vtable_length +
925 itable_length +
926 nonstatic_oop_map_size +
927 (is_interface ? (int)sizeof(Klass*)/wordSize : 0));
928 }
929
930 int size() const { return size(vtable_length(),
931 itable_length(),
932 nonstatic_oop_map_size(),
933 is_interface());
934 }
935
936
937 inline intptr_t* start_of_itable() const;
938 inline intptr_t* end_of_itable() const;
939 inline oop static_field_base_raw();
940
941 inline OopMapBlock* start_of_nonstatic_oop_maps() const;
942 inline Klass** end_of_nonstatic_oop_maps() const;
943
944 inline InstanceKlass* volatile* adr_implementor() const;
945
946 // Use this to return the size of an instance in heap words:
947 int size_helper() const {
948 return layout_helper_to_size_helper(layout_helper());
949 }
950
951 // This bit is initialized in classFileParser.cpp.
952 // It is false under any of the following conditions:
953 // - the class is abstract (including any interface)
954 // - the class size is larger than FastAllocateSizeLimit
955 // - the class is java/lang/Class, which cannot be allocated directly
956 bool can_be_fastpath_allocated() const {
957 return !layout_helper_needs_slow_path(layout_helper());
958 }
959
960 // Java itable
961 klassItable itable() const; // return klassItable wrapper
962 Method* method_at_itable(InstanceKlass* holder, int index, TRAPS);
963 Method* method_at_itable_or_null(InstanceKlass* holder, int index, bool& itable_entry_found);
964 int vtable_index_of_interface_method(Method* method);
965
966 #if INCLUDE_JVMTI
967 void adjust_default_methods(bool* trace_name_printed);
968 #endif // INCLUDE_JVMTI
969
970 void clean_weak_instanceklass_links();
971 private:
972 void clean_implementors_list();
973 void clean_method_data();
974
975 public:
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 const Klass* super_klass,
984 Array<InstanceKlass*>* local_interfaces,
985 Array<InstanceKlass*>* transitive_interfaces);
986 void static deallocate_record_components(ClassLoaderData* loader_data,
987 Array<RecordComponent*>* record_component);
988
989 virtual bool on_stack() const;
990
991 // callbacks for actions during class unloading
992 static void unload_class(InstanceKlass* ik);
993
994 virtual void release_C_heap_structures(bool release_sub_metadata = true);
995
996 // Naming
997 const char* signature_name() const;
998
999 // Oop fields (and metadata) iterators
1000 //
1001 // The InstanceKlass iterators also visits the Object's klass.
1002
1003 // Forward iteration
1004 public:
1005 // Iterate over all oop fields in the oop maps.
1006 template <typename T, class OopClosureType>
1007 inline void oop_oop_iterate_oop_maps(oop obj, OopClosureType* closure);
1008
1009 // Iterate over all oop fields and metadata.
1010 template <typename T, class OopClosureType>
1011 inline void oop_oop_iterate(oop obj, OopClosureType* closure);
1012
1013 // Iterate over all oop fields in one oop map.
1014 template <typename T, class OopClosureType>
1015 inline void oop_oop_iterate_oop_map(OopMapBlock* map, oop obj, OopClosureType* closure);
1016
1017
1018 // Reverse iteration
1019 // Iterate over all oop fields and metadata.
1020 template <typename T, class OopClosureType>
1021 inline void oop_oop_iterate_reverse(oop obj, OopClosureType* closure);
1022
1023 private:
1024 // Iterate over all oop fields in the oop maps.
1025 template <typename T, class OopClosureType>
1026 inline void oop_oop_iterate_oop_maps_reverse(oop obj, OopClosureType* closure);
1027
1028 // Iterate over all oop fields in one oop map.
1029 template <typename T, class OopClosureType>
1030 inline void oop_oop_iterate_oop_map_reverse(OopMapBlock* map, oop obj, OopClosureType* closure);
1031
1032
1033 // Bounded range iteration
1034 public:
1035 // Iterate over all oop fields in the oop maps.
1036 template <typename T, class OopClosureType>
1037 inline void oop_oop_iterate_oop_maps_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1038
1039 // Iterate over all oop fields and metadata.
1040 template <typename T, class OopClosureType>
1041 inline void oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1042
1043 private:
1044 // Iterate over all oop fields in one oop map.
1045 template <typename T, class OopClosureType>
1046 inline void oop_oop_iterate_oop_map_bounded(OopMapBlock* map, oop obj, OopClosureType* closure, MemRegion mr);
1047
1048
1049 public:
1050 u2 idnum_allocated_count() const { return _idnum_allocated_count; }
1051
1052 private:
1053 // initialization state
1054 void set_init_state(ClassState state);
1055 void set_rewritten() { _misc_flags.set_rewritten(true); }
1056 void set_init_thread(JavaThread *thread) {
1057 assert((thread == JavaThread::current() && _init_thread == nullptr) ||
1058 (thread == nullptr && _init_thread == JavaThread::current()), "Only one thread is allowed to own initialization");
1059 Atomic::store(&_init_thread, thread);
1060 }
1061
1062 inline jmethodID* methods_jmethod_ids_acquire() const;
1063 inline void release_set_methods_jmethod_ids(jmethodID* jmeths);
1064 // This nulls out jmethodIDs for all methods in 'klass'
1065 static void clear_jmethod_ids(InstanceKlass* klass);
1066 jmethodID update_jmethod_id(jmethodID* jmeths, Method* method, int idnum);
1067
1068 public:
1069 // Lock for (1) initialization; (2) access to the ConstantPool of this class.
1070 // Must be one per class and it has to be a VM internal object so java code
1071 // cannot lock it (like the mirror).
1072 // It has to be an object not a Mutex because it's held through java calls.
1073 oop init_lock() const;
1074
1075 // Returns the array class for the n'th dimension
1076 virtual ArrayKlass* array_klass(int n, TRAPS);
1077 virtual ArrayKlass* array_klass_or_null(int n);
1078
1079 // Returns the array class with this class as element type
1080 virtual ArrayKlass* array_klass(TRAPS);
1081 virtual ArrayKlass* array_klass_or_null();
1082
1083 static void clean_initialization_error_table();
1084 private:
1085 void fence_and_clear_init_lock();
1086
1087 bool link_class_impl (TRAPS);
1088 bool verify_code (TRAPS);
1089 void initialize_impl (TRAPS);
1090 void initialize_super_interfaces (TRAPS);
1091
1092 void add_initialization_error(JavaThread* current, Handle exception);
1093 oop get_initialization_error(JavaThread* current);
1094
1095 // find a local method (returns null if not found)
1096 Method* find_method_impl(const Symbol* name,
1097 const Symbol* signature,
1098 OverpassLookupMode overpass_mode,
1099 StaticLookupMode static_mode,
1100 PrivateLookupMode private_mode) const;
1101
1102 static Method* find_method_impl(const Array<Method*>* methods,
1103 const Symbol* name,
1104 const Symbol* signature,
1105 OverpassLookupMode overpass_mode,
1106 StaticLookupMode static_mode,
1107 PrivateLookupMode private_mode);
1108
1109 #if INCLUDE_JVMTI
1110 // RedefineClasses support
1111 void link_previous_versions(InstanceKlass* pv) { _previous_versions = pv; }
1112 void mark_newly_obsolete_methods(Array<Method*>* old_methods, int emcp_method_count);
1113 #endif
1114 // log class name to classlist
1115 void log_to_classlist() const;
1116 public:
1117
1118 #if INCLUDE_CDS
1119 // CDS support - remove and restore oops from metadata. Oops are not shared.
1120 virtual void remove_unshareable_info();
1121 void remove_unshareable_flags();
1122 virtual void remove_java_mirror();
1123 void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, PackageEntry* pkg_entry, TRAPS);
1124 void init_shared_package_entry();
1125 bool can_be_verified_at_dumptime() const;
1126 void compute_has_loops_flag_for_methods();
1127 #endif
1128
1129 u2 compute_modifier_flags() const;
1130
1131 public:
1132 // JVMTI support
1133 jint jvmti_class_status() const;
1134
1135 virtual void metaspace_pointers_do(MetaspaceClosure* iter);
1136
1137 public:
1138 // Printing
1139 void print_on(outputStream* st) const;
1140 void print_value_on(outputStream* st) const;
1141
1142 void oop_print_value_on(oop obj, outputStream* st);
1143
1144 void oop_print_on (oop obj, outputStream* st);
1145
1146 #ifndef PRODUCT
1147 void print_dependent_nmethods(bool verbose = false);
1148 bool is_dependent_nmethod(nmethod* nm);
1149 bool verify_itable_index(int index);
1150 #endif
1151
1152 const char* internal_name() const;
1153
1154 // Verification
1155 void verify_on(outputStream* st);
1156
1157 void oop_verify_on(oop obj, outputStream* st);
1158
1159 // Logging
1160 void print_class_load_logging(ClassLoaderData* loader_data,
1161 const ModuleEntry* module_entry,
1162 const ClassFileStream* cfs) const;
1163 private:
1164 void print_class_load_cause_logging() const;
1165 void print_class_load_helper(ClassLoaderData* loader_data,
1166 const ModuleEntry* module_entry,
1167 const ClassFileStream* cfs) const;
1168 };
1169
1170 // for adding methods
1171 // UNSET_IDNUM return means no more ids available
1172 inline u2 InstanceKlass::next_method_idnum() {
1173 if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1174 return ConstMethod::UNSET_IDNUM; // no more ids available
1175 } else {
1176 return _idnum_allocated_count++;
1177 }
1178 }
1179
1180 class PrintClassClosure : public KlassClosure {
1181 private:
1182 outputStream* _st;
1183 bool _verbose;
1184 public:
1185 PrintClassClosure(outputStream* st, bool verbose);
1186
1187 void do_klass(Klass* k);
1188 };
1189
1190 /* JNIid class for jfieldIDs only */
1191 class JNIid: public CHeapObj<mtClass> {
1192 friend class VMStructs;
1193 private:
1194 Klass* _holder;
1195 JNIid* _next;
1196 int _offset;
1197 #ifdef ASSERT
1198 bool _is_static_field_id;
1199 #endif
1200
1201 public:
1202 // Accessors
1203 Klass* holder() const { return _holder; }
1204 int offset() const { return _offset; }
1205 JNIid* next() { return _next; }
1206 // Constructor
1207 JNIid(Klass* holder, int offset, JNIid* next);
1208 // Identifier lookup
1209 JNIid* find(int offset);
1210
1211 bool find_local_field(fieldDescriptor* fd) {
1212 return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1213 }
1214
1215 static void deallocate(JNIid* id);
1216 // Debugging
1217 #ifdef ASSERT
1218 bool is_static_field_id() const { return _is_static_field_id; }
1219 void set_is_static_field_id() { _is_static_field_id = true; }
1220 #endif
1221 void verify(Klass* holder);
1222 };
1223
1224 // An iterator that's used to access the inner classes indices in the
1225 // InstanceKlass::_inner_classes array.
1226 class InnerClassesIterator : public StackObj {
1227 private:
1228 Array<jushort>* _inner_classes;
1229 int _length;
1230 int _idx;
1231 public:
1232
1233 InnerClassesIterator(const InstanceKlass* k) {
1234 _inner_classes = k->inner_classes();
1235 if (k->inner_classes() != nullptr) {
1236 _length = _inner_classes->length();
1237 // The inner class array's length should be the multiple of
1238 // inner_class_next_offset if it only contains the InnerClasses
1239 // attribute data, or it should be
1240 // n*inner_class_next_offset+enclosing_method_attribute_size
1241 // if it also contains the EnclosingMethod data.
1242 assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1243 _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1244 "just checking");
1245 // Remove the enclosing_method portion if exists.
1246 if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1247 _length -= InstanceKlass::enclosing_method_attribute_size;
1248 }
1249 } else {
1250 _length = 0;
1251 }
1252 _idx = 0;
1253 }
1254
1255 int length() const {
1256 return _length;
1257 }
1258
1259 void next() {
1260 _idx += InstanceKlass::inner_class_next_offset;
1261 }
1262
1263 bool done() const {
1264 return (_idx >= _length);
1265 }
1266
1267 u2 inner_class_info_index() const {
1268 return _inner_classes->at(
1269 _idx + InstanceKlass::inner_class_inner_class_info_offset);
1270 }
1271
1272 void set_inner_class_info_index(u2 index) {
1273 _inner_classes->at_put(
1274 _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1275 }
1276
1277 u2 outer_class_info_index() const {
1278 return _inner_classes->at(
1279 _idx + InstanceKlass::inner_class_outer_class_info_offset);
1280 }
1281
1282 void set_outer_class_info_index(u2 index) {
1283 _inner_classes->at_put(
1284 _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1285 }
1286
1287 u2 inner_name_index() const {
1288 return _inner_classes->at(
1289 _idx + InstanceKlass::inner_class_inner_name_offset);
1290 }
1291
1292 void set_inner_name_index(u2 index) {
1293 _inner_classes->at_put(
1294 _idx + InstanceKlass::inner_class_inner_name_offset, index);
1295 }
1296
1297 u2 inner_access_flags() const {
1298 return _inner_classes->at(
1299 _idx + InstanceKlass::inner_class_access_flags_offset);
1300 }
1301 };
1302
1303 // Iterator over class hierarchy under a particular class. Implements depth-first pre-order traversal.
1304 // Usage:
1305 // for (ClassHierarchyIterator iter(root_klass); !iter.done(); iter.next()) {
1306 // Klass* k = iter.klass();
1307 // ...
1308 // }
1309 class ClassHierarchyIterator : public StackObj {
1310 private:
1311 InstanceKlass* _root;
1312 Klass* _current;
1313 bool _visit_subclasses;
1314
1315 public:
1316 ClassHierarchyIterator(InstanceKlass* root) : _root(root), _current(root), _visit_subclasses(true) {
1317 assert(_root == _current, "required"); // initial state
1318 }
1319
1320 bool done() {
1321 return (_current == nullptr);
1322 }
1323
1324 // Make a step iterating over the class hierarchy under the root class.
1325 // Skips subclasses if requested.
1326 void next();
1327
1328 Klass* klass() {
1329 assert(!done(), "sanity");
1330 return _current;
1331 }
1332
1333 // Skip subclasses of the current class.
1334 void skip_subclasses() {
1335 _visit_subclasses = false;
1336 }
1337 };
1338
1339 #endif // SHARE_OOPS_INSTANCEKLASS_HPP