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