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 void set_shared_class_loader_type(s2 loader_type) { _misc_flags.set_shared_class_loader_type(loader_type); }
327 void assign_class_loader_type() { _misc_flags.assign_class_loader_type(_class_loader_data); }
328 #endif
329
330 bool has_nonstatic_fields() const { return _misc_flags.has_nonstatic_fields(); }
331 void set_has_nonstatic_fields(bool b) { _misc_flags.set_has_nonstatic_fields(b); }
332
333 bool has_localvariable_table() const { return _misc_flags.has_localvariable_table(); }
334 void set_has_localvariable_table(bool b) { _misc_flags.set_has_localvariable_table(b); }
335
336 // field sizes
337 int nonstatic_field_size() const { return _nonstatic_field_size; }
338 void set_nonstatic_field_size(int size) { _nonstatic_field_size = size; }
339
340 int static_field_size() const { return _static_field_size; }
341 void set_static_field_size(int size) { _static_field_size = size; }
342
343 int static_oop_field_count() const { return (int)_static_oop_field_count; }
344 void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
345
346 // Java itable
347 int itable_length() const { return _itable_len; }
348 void set_itable_length(int len) { _itable_len = len; }
349
350 // array klasses
351 ObjArrayKlass* array_klasses() const { return _array_klasses; }
352 inline ObjArrayKlass* array_klasses_acquire() const; // load with acquire semantics
353 inline void release_set_array_klasses(ObjArrayKlass* k); // store with release semantics
354 void set_array_klasses(ObjArrayKlass* k) { _array_klasses = k; }
355
356 // methods
357 Array<Method*>* methods() const { return _methods; }
358 void set_methods(Array<Method*>* a) { _methods = a; }
359 Method* method_with_idnum(int idnum);
360 Method* method_with_orig_idnum(int idnum);
361 Method* method_with_orig_idnum(int idnum, int version);
362
363 // method ordering
364 Array<int>* method_ordering() const { return _method_ordering; }
365 void set_method_ordering(Array<int>* m) { _method_ordering = m; }
366 void copy_method_ordering(const intArray* m, TRAPS);
367
368 // default_methods
369 Array<Method*>* default_methods() const { return _default_methods; }
370 void set_default_methods(Array<Method*>* a) { _default_methods = a; }
371
372 // default method vtable_indices
373 Array<int>* default_vtable_indices() const { return _default_vtable_indices; }
374 void set_default_vtable_indices(Array<int>* v) { _default_vtable_indices = v; }
375 Array<int>* create_new_default_vtable_indices(int len, TRAPS);
376
377 // interfaces
378 Array<InstanceKlass*>* local_interfaces() const { return _local_interfaces; }
379 void set_local_interfaces(Array<InstanceKlass*>* a) {
380 guarantee(_local_interfaces == nullptr || a == nullptr, "Just checking");
381 _local_interfaces = a; }
382
383 Array<InstanceKlass*>* transitive_interfaces() const { return _transitive_interfaces; }
384 void set_transitive_interfaces(Array<InstanceKlass*>* a) {
385 guarantee(_transitive_interfaces == nullptr || a == nullptr, "Just checking");
386 _transitive_interfaces = a;
387 }
388
389 private:
390 friend class fieldDescriptor;
391 FieldInfo field(int index) const;
392
393 public:
394 int field_offset (int index) const { return field(index).offset(); }
395 int field_access_flags(int index) const { return field(index).access_flags().as_int(); }
396 FieldInfo::FieldFlags field_flags(int index) const { return field(index).field_flags(); }
397 FieldStatus field_status(int index) const { return fields_status()->at(index); }
398 inline Symbol* field_name (int index) const;
399 inline Symbol* field_signature (int index) const;
400
401 // Number of Java declared fields
402 int java_fields_count() const;
403 int total_fields_count() const;
404
405 Array<u1>* fieldinfo_stream() const { return _fieldinfo_stream; }
406 void set_fieldinfo_stream(Array<u1>* fis) { _fieldinfo_stream = fis; }
407
408 Array<FieldStatus>* fields_status() const {return _fields_status; }
409 void set_fields_status(Array<FieldStatus>* array) { _fields_status = array; }
410
411 // inner classes
412 Array<u2>* inner_classes() const { return _inner_classes; }
413 void set_inner_classes(Array<u2>* f) { _inner_classes = f; }
414
415 // nest members
416 Array<u2>* nest_members() const { return _nest_members; }
417 void set_nest_members(Array<u2>* m) { _nest_members = m; }
418
419 // nest-host index
420 jushort nest_host_index() const { return _nest_host_index; }
421 void set_nest_host_index(u2 i) { _nest_host_index = i; }
422 // dynamic nest member support
423 void set_nest_host(InstanceKlass* host);
424
425 // record components
426 Array<RecordComponent*>* record_components() const { return _record_components; }
427 void set_record_components(Array<RecordComponent*>* record_components) {
428 _record_components = record_components;
429 }
430 bool is_record() const;
431
432 // permitted subclasses
433 Array<u2>* permitted_subclasses() const { return _permitted_subclasses; }
434 void set_permitted_subclasses(Array<u2>* s) { _permitted_subclasses = s; }
435
436 private:
437 // Called to verify that k is a member of this nest - does not look at k's nest-host,
438 // nor does it resolve any CP entries or load any classes.
439 bool has_nest_member(JavaThread* current, InstanceKlass* k) const;
440
441 public:
442 // Call this only if you know that the nest host has been initialized.
443 InstanceKlass* nest_host_not_null() {
444 assert(_nest_host != nullptr, "must be");
445 return _nest_host;
446 }
447 // Used to construct informative IllegalAccessError messages at a higher level,
448 // if there was an issue resolving or validating the nest host.
449 // Returns null if there was no error.
450 const char* nest_host_error();
451 // Returns nest-host class, resolving and validating it if needed.
452 // Returns null if resolution is not possible from the calling context.
453 InstanceKlass* nest_host(TRAPS);
454 // Check if this klass is a nestmate of k - resolves this nest-host and k's
455 bool has_nestmate_access_to(InstanceKlass* k, TRAPS);
456
457 // Called to verify that k is a permitted subclass of this class
458 bool has_as_permitted_subclass(const InstanceKlass* k) const;
459
460 enum InnerClassAttributeOffset {
461 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
462 inner_class_inner_class_info_offset = 0,
463 inner_class_outer_class_info_offset = 1,
464 inner_class_inner_name_offset = 2,
465 inner_class_access_flags_offset = 3,
466 inner_class_next_offset = 4
467 };
468
469 enum EnclosingMethodAttributeOffset {
470 enclosing_method_class_index_offset = 0,
471 enclosing_method_method_index_offset = 1,
472 enclosing_method_attribute_size = 2
473 };
474
475 // package
476 PackageEntry* package() const { return _package_entry; }
477 ModuleEntry* module() const;
478 bool in_unnamed_package() const { return (_package_entry == nullptr); }
479 void set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS);
480 // If the package for the InstanceKlass is in the boot loader's package entry
481 // table then sets the classpath_index field so that
482 // get_system_package() will know to return a non-null value for the
483 // package's location. And, so that the package will be added to the list of
484 // packages returned by get_system_packages().
485 // For packages whose classes are loaded from the boot loader class path, the
486 // classpath_index indicates which entry on the boot loader class path.
487 void set_classpath_index(s2 path_index);
488 bool is_same_class_package(const Klass* class2) const;
489 bool is_same_class_package(oop other_class_loader, const Symbol* other_class_name) const;
490
491 // find an enclosing class
492 InstanceKlass* compute_enclosing_class(bool* inner_is_member, TRAPS) const;
493
494 // Find InnerClasses attribute and return outer_class_info_index & inner_name_index.
495 bool find_inner_classes_attr(int* ooff, int* noff, TRAPS) const;
496
497 private:
498 // Check prohibited package ("java/" only loadable by boot or platform loaders)
499 static void check_prohibited_package(Symbol* class_name,
500 ClassLoaderData* loader_data,
501 TRAPS);
502
503 JavaThread* init_thread() { return Atomic::load(&_init_thread); }
504 const char* init_thread_name() {
505 return init_thread()->name_raw();
506 }
507
508 public:
509 // initialization state
510 bool is_loaded() const { return init_state() >= loaded; }
511 bool is_linked() const { return init_state() >= linked; }
512 bool is_initialized() const { return init_state() == fully_initialized; }
513 bool is_not_initialized() const { return init_state() < being_initialized; }
514 bool is_being_initialized() const { return init_state() == being_initialized; }
515 bool is_in_error_state() const { return init_state() == initialization_error; }
516 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; }
517 ClassState init_state() const { return Atomic::load_acquire(&_init_state); }
518 const char* init_state_name() const;
519 bool is_rewritten() const { return _misc_flags.rewritten(); }
520
521 // is this a sealed class
522 bool is_sealed() const;
523
524 // defineClass specified verification
525 bool should_verify_class() const { return _misc_flags.should_verify_class(); }
526 void set_should_verify_class(bool value) { _misc_flags.set_should_verify_class(value); }
527
528 // marking
529 bool is_marked_dependent() const { return _misc_flags.is_marked_dependent(); }
530 void set_is_marked_dependent(bool value) { _misc_flags.set_is_marked_dependent(value); }
531
532 // initialization (virtuals from Klass)
533 bool should_be_initialized() const; // means that initialize should be called
534 void initialize(TRAPS);
535 void link_class(TRAPS);
536 bool link_class_or_fail(TRAPS); // returns false on failure
537 void rewrite_class(TRAPS);
538 void link_methods(TRAPS);
539 Method* class_initializer() const;
540
541 // reference type
542 ReferenceType reference_type() const { return (ReferenceType)_reference_type; }
543
544 // this class cp index
545 u2 this_class_index() const { return _this_class_index; }
546 void set_this_class_index(u2 index) { _this_class_index = index; }
547
548 static ByteSize reference_type_offset() { return byte_offset_of(InstanceKlass, _reference_type); }
549
550 // find local field, returns true if found
551 bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
552 // find field in direct superinterfaces, returns the interface in which the field is defined
553 Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
554 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
555 Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
556 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
557 Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
558
559 // find a non-static or static field given its offset within the class.
560 bool contains_field_offset(int offset);
561
562 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
563 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
564
565 private:
566 inline static int quick_search(const Array<Method*>* methods, const Symbol* name);
567
568 public:
569 static void disable_method_binary_search() {
570 _disable_method_binary_search = true;
571 }
572
573 // find a local method (returns null if not found)
574 Method* find_method(const Symbol* name, const Symbol* signature) const;
575 static Method* find_method(const Array<Method*>* methods,
576 const Symbol* name,
577 const Symbol* signature);
578
579 // find a local method, but skip static methods
580 Method* find_instance_method(const Symbol* name, const Symbol* signature,
581 PrivateLookupMode private_mode) const;
582 static Method* find_instance_method(const Array<Method*>* methods,
583 const Symbol* name,
584 const Symbol* signature,
585 PrivateLookupMode private_mode);
586
587 // find a local method (returns null if not found)
588 Method* find_local_method(const Symbol* name,
589 const Symbol* signature,
590 OverpassLookupMode overpass_mode,
591 StaticLookupMode static_mode,
592 PrivateLookupMode private_mode) const;
593
594 // find a local method from given methods array (returns null if not found)
595 static Method* find_local_method(const Array<Method*>* methods,
596 const Symbol* name,
597 const Symbol* signature,
598 OverpassLookupMode overpass_mode,
599 StaticLookupMode static_mode,
600 PrivateLookupMode private_mode);
601
602 // find a local method index in methods or default_methods (returns -1 if not found)
603 static int find_method_index(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 // lookup operation (returns null if not found)
611 Method* uncached_lookup_method(const Symbol* name,
612 const Symbol* signature,
613 OverpassLookupMode overpass_mode,
614 PrivateLookupMode private_mode = PrivateLookupMode::find) const;
615
616 // lookup a method in all the interfaces that this class implements
617 // (returns null if not found)
618 Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature, DefaultsLookupMode defaults_mode) const;
619
620 // lookup a method in local defaults then in all interfaces
621 // (returns null if not found)
622 Method* lookup_method_in_ordered_interfaces(Symbol* name, Symbol* signature) const;
623
624 // Find method indices by name. If a method with the specified name is
625 // found the index to the first method is returned, and 'end' is filled in
626 // with the index of first non-name-matching method. If no method is found
627 // -1 is returned.
628 int find_method_by_name(const Symbol* name, int* end) const;
629 static int find_method_by_name(const Array<Method*>* methods,
630 const Symbol* name, int* end);
631
632 // constant pool
633 ConstantPool* constants() const { return _constants; }
634 void set_constants(ConstantPool* c) { _constants = c; }
635
636 // protection domain
637 oop protection_domain() const;
638
639 // signers
640 objArrayOop signers() const;
641
642 bool is_contended() const { return _misc_flags.is_contended(); }
643 void set_is_contended(bool value) { _misc_flags.set_is_contended(value); }
644
645 // source file name
646 Symbol* source_file_name() const;
647 u2 source_file_name_index() const;
648 void set_source_file_name_index(u2 sourcefile_index);
649
650 // minor and major version numbers of class file
651 u2 minor_version() const;
652 void set_minor_version(u2 minor_version);
653 u2 major_version() const;
654 void set_major_version(u2 major_version);
655
656 // source debug extension
657 const char* source_debug_extension() const { return _source_debug_extension; }
658 void set_source_debug_extension(const char* array, int length);
659
660 // nonstatic oop-map blocks
661 static int nonstatic_oop_map_size(unsigned int oop_map_count) {
662 return oop_map_count * OopMapBlock::size_in_words();
663 }
664 unsigned int nonstatic_oop_map_count() const {
665 return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
666 }
667 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
668 void set_nonstatic_oop_map_size(int words) {
669 _nonstatic_oop_map_size = words;
670 }
671
672 bool has_contended_annotations() const { return _misc_flags.has_contended_annotations(); }
673 void set_has_contended_annotations(bool value) { _misc_flags.set_has_contended_annotations(value); }
674
675 #if INCLUDE_JVMTI
676 // Redefinition locking. Class can only be redefined by one thread at a time.
677 // The flag is in access_flags so that it can be set and reset using atomic
678 // operations, and not be reset by other misc_flag settings.
679 bool is_being_redefined() const { return _misc_flags.is_being_redefined(); }
680 void set_is_being_redefined(bool value) { _misc_flags.set_is_being_redefined(value); }
681
682 // RedefineClasses() support for previous versions:
683 void add_previous_version(InstanceKlass* ik, int emcp_method_count);
684 void purge_previous_version_list();
685
686 InstanceKlass* previous_versions() const { return _previous_versions; }
687 #else
688 InstanceKlass* previous_versions() const { return nullptr; }
689 #endif
690
691 InstanceKlass* get_klass_version(int version);
692
693 bool has_been_redefined() const { return _misc_flags.has_been_redefined(); }
694 void set_has_been_redefined() { _misc_flags.set_has_been_redefined(true); }
695
696 bool is_scratch_class() const { return _misc_flags.is_scratch_class(); }
697 void set_is_scratch_class() { _misc_flags.set_is_scratch_class(true); }
698
699 bool has_resolved_methods() const { return _misc_flags.has_resolved_methods(); }
700 void set_has_resolved_methods() { _misc_flags.set_has_resolved_methods(true); }
701 void set_has_resolved_methods(bool value) { _misc_flags.set_has_resolved_methods(value); }
702
703 public:
704 #if INCLUDE_JVMTI
705
706 void init_previous_versions() {
707 _previous_versions = nullptr;
708 }
709
710 private:
711 static bool _should_clean_previous_versions;
712 public:
713 static void purge_previous_versions(InstanceKlass* ik) {
714 if (ik->has_been_redefined()) {
715 ik->purge_previous_version_list();
716 }
717 }
718
719 static bool should_clean_previous_versions_and_reset();
720 static bool should_clean_previous_versions() { return _should_clean_previous_versions; }
721
722 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
723 void set_cached_class_file(JvmtiCachedClassFileData *data) {
724 _cached_class_file = data;
725 }
726 JvmtiCachedClassFileData * get_cached_class_file();
727 jint get_cached_class_file_len();
728 unsigned char * get_cached_class_file_bytes();
729
730 // JVMTI: Support for caching of field indices, types, and offsets
731 void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
732 _jvmti_cached_class_field_map = descriptor;
733 }
734 JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
735 return _jvmti_cached_class_field_map;
736 }
737 #else // INCLUDE_JVMTI
738
739 static void purge_previous_versions(InstanceKlass* ik) { return; };
740 static bool should_clean_previous_versions_and_reset() { return false; }
741
742 void set_cached_class_file(JvmtiCachedClassFileData *data) {
743 assert(data == nullptr, "unexpected call with JVMTI disabled");
744 }
745 JvmtiCachedClassFileData * get_cached_class_file() { return (JvmtiCachedClassFileData *)nullptr; }
746
747 #endif // INCLUDE_JVMTI
748
749 bool has_nonstatic_concrete_methods() const { return _misc_flags.has_nonstatic_concrete_methods(); }
750 void set_has_nonstatic_concrete_methods(bool b) { _misc_flags.set_has_nonstatic_concrete_methods(b); }
751
752 bool declares_nonstatic_concrete_methods() const { return _misc_flags.declares_nonstatic_concrete_methods(); }
753 void set_declares_nonstatic_concrete_methods(bool b) { _misc_flags.set_declares_nonstatic_concrete_methods(b); }
754
755 bool has_miranda_methods () const { return _misc_flags.has_miranda_methods(); }
756 void set_has_miranda_methods() { _misc_flags.set_has_miranda_methods(true); }
757 bool has_final_method() const { return _misc_flags.has_final_method(); }
758 void set_has_final_method() { _misc_flags.set_has_final_method(true); }
759
760 // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
761 inline u2 next_method_idnum();
762 void set_initial_method_idnum(u2 value) { _idnum_allocated_count = value; }
763
764 // generics support
765 Symbol* generic_signature() const;
766 u2 generic_signature_index() const;
767 void set_generic_signature_index(u2 sig_index);
768
769 u2 enclosing_method_data(int offset) const;
770 u2 enclosing_method_class_index() const {
771 return enclosing_method_data(enclosing_method_class_index_offset);
772 }
773 u2 enclosing_method_method_index() {
774 return enclosing_method_data(enclosing_method_method_index_offset);
775 }
776 void set_enclosing_method_indices(u2 class_index,
777 u2 method_index);
778
779 // jmethodID support
780 jmethodID get_jmethod_id(const methodHandle& method_h);
781 void ensure_space_for_methodids(int start_offset = 0);
782 jmethodID jmethod_id_or_null(Method* method);
783 void update_methods_jmethod_cache();
784
785 // annotations support
786 Annotations* annotations() const { return _annotations; }
787 void set_annotations(Annotations* anno) { _annotations = anno; }
788
789 AnnotationArray* class_annotations() const {
790 return (_annotations != nullptr) ? _annotations->class_annotations() : nullptr;
791 }
792 Array<AnnotationArray*>* fields_annotations() const {
793 return (_annotations != nullptr) ? _annotations->fields_annotations() : nullptr;
794 }
795 AnnotationArray* class_type_annotations() const {
796 return (_annotations != nullptr) ? _annotations->class_type_annotations() : nullptr;
797 }
798 Array<AnnotationArray*>* fields_type_annotations() const {
799 return (_annotations != nullptr) ? _annotations->fields_type_annotations() : nullptr;
800 }
801 // allocation
802 instanceOop allocate_instance(TRAPS);
803 static instanceOop allocate_instance(oop cls, TRAPS);
804
805 // additional member function to return a handle
806 instanceHandle allocate_instance_handle(TRAPS);
807
808 objArrayOop allocate_objArray(int n, int length, TRAPS);
809 // Helper function
810 static instanceOop register_finalizer(instanceOop i, TRAPS);
811
812 // Check whether reflection/jni/jvm code is allowed to instantiate this class;
813 // if not, throw either an Error or an Exception.
814 virtual void check_valid_for_instantiation(bool throwError, TRAPS);
815
816 // initialization
817 void call_class_initializer(TRAPS);
818 void set_initialization_state_and_notify(ClassState state, TRAPS);
819
820 // OopMapCache support
821 OopMapCache* oop_map_cache() { return _oop_map_cache; }
822 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
823 void mask_for(const methodHandle& method, int bci, InterpreterOopMap* entry);
824
825 // JNI identifier support (for static fields - for jni performance)
826 JNIid* jni_ids() { return _jni_ids; }
827 void set_jni_ids(JNIid* ids) { _jni_ids = ids; }
828 JNIid* jni_id_for(int offset);
829
830 public:
831 // maintenance of deoptimization dependencies
832 inline DependencyContext dependencies();
833 void mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes);
834 void add_dependent_nmethod(nmethod* nm);
835 void clean_dependency_context();
836 // Setup link to hierarchy and deoptimize
837 void add_to_hierarchy(JavaThread* current);
838
839 // On-stack replacement support
840 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; };
841 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; };
842 void add_osr_nmethod(nmethod* n);
843 bool remove_osr_nmethod(nmethod* n);
844 int mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m);
845 nmethod* lookup_osr_nmethod(const Method* m, int bci, int level, bool match_level) const;
846
847 #if INCLUDE_JVMTI
848 // Breakpoint support (see methods on Method* for details)
849 BreakpointInfo* breakpoints() const { return _breakpoints; };
850 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
851 #endif
852
853 // support for stub routines
854 static ByteSize init_state_offset() { return byte_offset_of(InstanceKlass, _init_state); }
855 JFR_ONLY(DEFINE_KLASS_TRACE_ID_OFFSET;)
856 static ByteSize init_thread_offset() { return byte_offset_of(InstanceKlass, _init_thread); }
857
858 // subclass/subinterface checks
859 bool implements_interface(Klass* k) const;
860 bool is_same_or_direct_interface(Klass* k) const;
861
862 #ifdef ASSERT
863 // check whether this class or one of its superclasses was redefined
864 bool has_redefined_this_or_super() const;
865 #endif
866
867 // Access to the implementor of an interface.
868 InstanceKlass* implementor() const;
869 void set_implementor(InstanceKlass* ik);
870 int nof_implementors() const;
871 void add_implementor(InstanceKlass* ik); // ik is a new class that implements this interface
872 void init_implementor(); // initialize
873
874 private:
875 // link this class into the implementors list of every interface it implements
876 void process_interfaces();
877
878 public:
879 // virtual operations from Klass
880 GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots,
881 Array<InstanceKlass*>* transitive_interfaces);
882 bool can_be_primary_super_slow() const;
883 size_t oop_size(oop obj) const { return size_helper(); }
884 // slow because it's a virtual call and used for verifying the layout_helper.
885 // Using the layout_helper bits, we can call is_instance_klass without a virtual call.
886 DEBUG_ONLY(bool is_instance_klass_slow() const { return true; })
887
888 // Iterators
889 void do_local_static_fields(FieldClosure* cl);
890 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
891 void do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle, TRAPS);
892 void print_nonstatic_fields(FieldClosure* cl); // including inherited and injected fields
893
894 void methods_do(void f(Method* method));
895
896 static InstanceKlass* cast(Klass* k) {
897 return const_cast<InstanceKlass*>(cast(const_cast<const Klass*>(k)));
898 }
899
900 static const InstanceKlass* cast(const Klass* k) {
901 assert(k != nullptr, "k should not be null");
902 assert(k->is_instance_klass(), "cast to InstanceKlass");
903 return static_cast<const InstanceKlass*>(k);
904 }
905
906 virtual InstanceKlass* java_super() const {
907 return (super() == nullptr) ? nullptr : cast(super());
908 }
909
910 // Sizing (in words)
911 static int header_size() { return sizeof(InstanceKlass)/wordSize; }
912
913 static int size(int vtable_length, int itable_length,
914 int nonstatic_oop_map_size,
915 bool is_interface) {
916 return align_metadata_size(header_size() +
917 vtable_length +
918 itable_length +
919 nonstatic_oop_map_size +
920 (is_interface ? (int)sizeof(Klass*)/wordSize : 0));
921 }
922
923 int size() const { return size(vtable_length(),
924 itable_length(),
925 nonstatic_oop_map_size(),
926 is_interface());
927 }
928
929
930 inline intptr_t* start_of_itable() const;
931 inline intptr_t* end_of_itable() const;
932 inline oop static_field_base_raw();
933
934 inline OopMapBlock* start_of_nonstatic_oop_maps() const;
935 inline Klass** end_of_nonstatic_oop_maps() const;
936
937 inline InstanceKlass* volatile* adr_implementor() const;
938
939 // Use this to return the size of an instance in heap words:
940 int size_helper() const {
941 return layout_helper_to_size_helper(layout_helper());
942 }
943
944 // This bit is initialized in classFileParser.cpp.
945 // It is false under any of the following conditions:
946 // - the class is abstract (including any interface)
947 // - the class size is larger than FastAllocateSizeLimit
948 // - the class is java/lang/Class, which cannot be allocated directly
949 bool can_be_fastpath_allocated() const {
950 return !layout_helper_needs_slow_path(layout_helper());
951 }
952
953 // Java itable
954 klassItable itable() const; // return klassItable wrapper
955 Method* method_at_itable(InstanceKlass* holder, int index, TRAPS);
956 Method* method_at_itable_or_null(InstanceKlass* holder, int index, bool& itable_entry_found);
957 int vtable_index_of_interface_method(Method* method);
958
959 #if INCLUDE_JVMTI
960 void adjust_default_methods(bool* trace_name_printed);
961 #endif // INCLUDE_JVMTI
962
963 void clean_weak_instanceklass_links();
964 private:
965 void clean_implementors_list();
966 void clean_method_data();
967
968 public:
969 // Explicit metaspace deallocation of fields
970 // For RedefineClasses and class file parsing errors, we need to deallocate
971 // instanceKlasses and the metadata they point to.
972 void deallocate_contents(ClassLoaderData* loader_data);
973 static void deallocate_methods(ClassLoaderData* loader_data,
974 Array<Method*>* methods);
975 void static deallocate_interfaces(ClassLoaderData* loader_data,
976 const Klass* super_klass,
977 Array<InstanceKlass*>* local_interfaces,
978 Array<InstanceKlass*>* transitive_interfaces);
979 void static deallocate_record_components(ClassLoaderData* loader_data,
980 Array<RecordComponent*>* record_component);
981
982 virtual bool on_stack() const;
983
984 // callbacks for actions during class unloading
985 static void unload_class(InstanceKlass* ik);
986
987 virtual void release_C_heap_structures(bool release_sub_metadata = true);
988
989 // Naming
990 const char* signature_name() const;
991
992 // Oop fields (and metadata) iterators
993 //
994 // The InstanceKlass iterators also visits the Object's klass.
995
996 // Forward iteration
997 public:
998 // Iterate over all oop fields in the oop maps.
999 template <typename T, class OopClosureType>
1000 inline void oop_oop_iterate_oop_maps(oop obj, OopClosureType* closure);
1001
1002 // Iterate over all oop fields and metadata.
1003 template <typename T, class OopClosureType>
1004 inline void oop_oop_iterate(oop obj, OopClosureType* closure);
1005
1006 // Iterate over all oop fields in one oop map.
1007 template <typename T, class OopClosureType>
1008 inline void oop_oop_iterate_oop_map(OopMapBlock* map, oop obj, OopClosureType* closure);
1009
1010
1011 // Reverse iteration
1012 // Iterate over all oop fields and metadata.
1013 template <typename T, class OopClosureType>
1014 inline void oop_oop_iterate_reverse(oop obj, OopClosureType* closure);
1015
1016 private:
1017 // Iterate over all oop fields in the oop maps.
1018 template <typename T, class OopClosureType>
1019 inline void oop_oop_iterate_oop_maps_reverse(oop obj, OopClosureType* closure);
1020
1021 // Iterate over all oop fields in one oop map.
1022 template <typename T, class OopClosureType>
1023 inline void oop_oop_iterate_oop_map_reverse(OopMapBlock* map, oop obj, OopClosureType* closure);
1024
1025
1026 // Bounded range iteration
1027 public:
1028 // Iterate over all oop fields in the oop maps.
1029 template <typename T, class OopClosureType>
1030 inline void oop_oop_iterate_oop_maps_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1031
1032 // Iterate over all oop fields and metadata.
1033 template <typename T, class OopClosureType>
1034 inline void oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1035
1036 private:
1037 // Iterate over all oop fields in one oop map.
1038 template <typename T, class OopClosureType>
1039 inline void oop_oop_iterate_oop_map_bounded(OopMapBlock* map, oop obj, OopClosureType* closure, MemRegion mr);
1040
1041
1042 public:
1043 u2 idnum_allocated_count() const { return _idnum_allocated_count; }
1044
1045 private:
1046 // initialization state
1047 void set_init_state(ClassState state);
1048 void set_rewritten() { _misc_flags.set_rewritten(true); }
1049 void set_init_thread(JavaThread *thread) {
1050 assert((thread == JavaThread::current() && _init_thread == nullptr) ||
1051 (thread == nullptr && _init_thread == JavaThread::current()), "Only one thread is allowed to own initialization");
1052 Atomic::store(&_init_thread, thread);
1053 }
1054
1055 inline jmethodID* methods_jmethod_ids_acquire() const;
1056 inline void release_set_methods_jmethod_ids(jmethodID* jmeths);
1057 // This nulls out jmethodIDs for all methods in 'klass'
1058 static void clear_jmethod_ids(InstanceKlass* klass);
1059 jmethodID update_jmethod_id(jmethodID* jmeths, Method* method, int idnum);
1060
1061 public:
1062 // Lock for (1) initialization; (2) access to the ConstantPool of this class.
1063 // Must be one per class and it has to be a VM internal object so java code
1064 // cannot lock it (like the mirror).
1065 // It has to be an object not a Mutex because it's held through java calls.
1066 oop init_lock() const;
1067
1068 // Returns the array class for the n'th dimension
1069 virtual ArrayKlass* array_klass(int n, TRAPS);
1070 virtual ArrayKlass* array_klass_or_null(int n);
1071
1072 // Returns the array class with this class as element type
1073 virtual ArrayKlass* array_klass(TRAPS);
1074 virtual ArrayKlass* array_klass_or_null();
1075
1076 static void clean_initialization_error_table();
1077 private:
1078 void fence_and_clear_init_lock();
1079
1080 bool link_class_impl (TRAPS);
1081 bool verify_code (TRAPS);
1082 void initialize_impl (TRAPS);
1083 void initialize_super_interfaces (TRAPS);
1084
1085 void add_initialization_error(JavaThread* current, Handle exception);
1086 oop get_initialization_error(JavaThread* current);
1087
1088 // find a local method (returns null if not found)
1089 Method* find_method_impl(const Symbol* name,
1090 const Symbol* signature,
1091 OverpassLookupMode overpass_mode,
1092 StaticLookupMode static_mode,
1093 PrivateLookupMode private_mode) const;
1094
1095 static Method* find_method_impl(const Array<Method*>* methods,
1096 const Symbol* name,
1097 const Symbol* signature,
1098 OverpassLookupMode overpass_mode,
1099 StaticLookupMode static_mode,
1100 PrivateLookupMode private_mode);
1101
1102 #if INCLUDE_JVMTI
1103 // RedefineClasses support
1104 void link_previous_versions(InstanceKlass* pv) { _previous_versions = pv; }
1105 void mark_newly_obsolete_methods(Array<Method*>* old_methods, int emcp_method_count);
1106 #endif
1107 // log class name to classlist
1108 void log_to_classlist() const;
1109 public:
1110
1111 #if INCLUDE_CDS
1112 // CDS support - remove and restore oops from metadata. Oops are not shared.
1113 virtual void remove_unshareable_info();
1114 void remove_unshareable_flags();
1115 virtual void remove_java_mirror();
1116 void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, PackageEntry* pkg_entry, TRAPS);
1117 void init_shared_package_entry();
1118 bool can_be_verified_at_dumptime() const;
1119 void compute_has_loops_flag_for_methods();
1120 #endif
1121
1122 jint compute_modifier_flags() const;
1123
1124 public:
1125 // JVMTI support
1126 jint jvmti_class_status() const;
1127
1128 virtual void metaspace_pointers_do(MetaspaceClosure* iter);
1129
1130 public:
1131 // Printing
1132 void print_on(outputStream* st) const;
1133 void print_value_on(outputStream* st) const;
1134
1135 void oop_print_value_on(oop obj, outputStream* st);
1136
1137 void oop_print_on (oop obj, outputStream* st);
1138
1139 #ifndef PRODUCT
1140 void print_dependent_nmethods(bool verbose = false);
1141 bool is_dependent_nmethod(nmethod* nm);
1142 bool verify_itable_index(int index);
1143 #endif
1144
1145 const char* internal_name() const;
1146
1147 // Verification
1148 void verify_on(outputStream* st);
1149
1150 void oop_verify_on(oop obj, outputStream* st);
1151
1152 // Logging
1153 void print_class_load_logging(ClassLoaderData* loader_data,
1154 const ModuleEntry* module_entry,
1155 const ClassFileStream* cfs) const;
1156 private:
1157 void print_class_load_cause_logging() const;
1158 void print_class_load_helper(ClassLoaderData* loader_data,
1159 const ModuleEntry* module_entry,
1160 const ClassFileStream* cfs) const;
1161 };
1162
1163 // for adding methods
1164 // UNSET_IDNUM return means no more ids available
1165 inline u2 InstanceKlass::next_method_idnum() {
1166 if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1167 return ConstMethod::UNSET_IDNUM; // no more ids available
1168 } else {
1169 return _idnum_allocated_count++;
1170 }
1171 }
1172
1173 class PrintClassClosure : public KlassClosure {
1174 private:
1175 outputStream* _st;
1176 bool _verbose;
1177 public:
1178 PrintClassClosure(outputStream* st, bool verbose);
1179
1180 void do_klass(Klass* k);
1181 };
1182
1183 /* JNIid class for jfieldIDs only */
1184 class JNIid: public CHeapObj<mtClass> {
1185 friend class VMStructs;
1186 private:
1187 Klass* _holder;
1188 JNIid* _next;
1189 int _offset;
1190 #ifdef ASSERT
1191 bool _is_static_field_id;
1192 #endif
1193
1194 public:
1195 // Accessors
1196 Klass* holder() const { return _holder; }
1197 int offset() const { return _offset; }
1198 JNIid* next() { return _next; }
1199 // Constructor
1200 JNIid(Klass* holder, int offset, JNIid* next);
1201 // Identifier lookup
1202 JNIid* find(int offset);
1203
1204 bool find_local_field(fieldDescriptor* fd) {
1205 return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1206 }
1207
1208 static void deallocate(JNIid* id);
1209 // Debugging
1210 #ifdef ASSERT
1211 bool is_static_field_id() const { return _is_static_field_id; }
1212 void set_is_static_field_id() { _is_static_field_id = true; }
1213 #endif
1214 void verify(Klass* holder);
1215 };
1216
1217 // An iterator that's used to access the inner classes indices in the
1218 // InstanceKlass::_inner_classes array.
1219 class InnerClassesIterator : public StackObj {
1220 private:
1221 Array<jushort>* _inner_classes;
1222 int _length;
1223 int _idx;
1224 public:
1225
1226 InnerClassesIterator(const InstanceKlass* k) {
1227 _inner_classes = k->inner_classes();
1228 if (k->inner_classes() != nullptr) {
1229 _length = _inner_classes->length();
1230 // The inner class array's length should be the multiple of
1231 // inner_class_next_offset if it only contains the InnerClasses
1232 // attribute data, or it should be
1233 // n*inner_class_next_offset+enclosing_method_attribute_size
1234 // if it also contains the EnclosingMethod data.
1235 assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1236 _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1237 "just checking");
1238 // Remove the enclosing_method portion if exists.
1239 if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1240 _length -= InstanceKlass::enclosing_method_attribute_size;
1241 }
1242 } else {
1243 _length = 0;
1244 }
1245 _idx = 0;
1246 }
1247
1248 int length() const {
1249 return _length;
1250 }
1251
1252 void next() {
1253 _idx += InstanceKlass::inner_class_next_offset;
1254 }
1255
1256 bool done() const {
1257 return (_idx >= _length);
1258 }
1259
1260 u2 inner_class_info_index() const {
1261 return _inner_classes->at(
1262 _idx + InstanceKlass::inner_class_inner_class_info_offset);
1263 }
1264
1265 void set_inner_class_info_index(u2 index) {
1266 _inner_classes->at_put(
1267 _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1268 }
1269
1270 u2 outer_class_info_index() const {
1271 return _inner_classes->at(
1272 _idx + InstanceKlass::inner_class_outer_class_info_offset);
1273 }
1274
1275 void set_outer_class_info_index(u2 index) {
1276 _inner_classes->at_put(
1277 _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1278 }
1279
1280 u2 inner_name_index() const {
1281 return _inner_classes->at(
1282 _idx + InstanceKlass::inner_class_inner_name_offset);
1283 }
1284
1285 void set_inner_name_index(u2 index) {
1286 _inner_classes->at_put(
1287 _idx + InstanceKlass::inner_class_inner_name_offset, index);
1288 }
1289
1290 u2 inner_access_flags() const {
1291 return _inner_classes->at(
1292 _idx + InstanceKlass::inner_class_access_flags_offset);
1293 }
1294 };
1295
1296 // Iterator over class hierarchy under a particular class. Implements depth-first pre-order traversal.
1297 // Usage:
1298 // for (ClassHierarchyIterator iter(root_klass); !iter.done(); iter.next()) {
1299 // Klass* k = iter.klass();
1300 // ...
1301 // }
1302 class ClassHierarchyIterator : public StackObj {
1303 private:
1304 InstanceKlass* _root;
1305 Klass* _current;
1306 bool _visit_subclasses;
1307
1308 public:
1309 ClassHierarchyIterator(InstanceKlass* root) : _root(root), _current(root), _visit_subclasses(true) {
1310 assert(_root == _current, "required"); // initial state
1311 }
1312
1313 bool done() {
1314 return (_current == nullptr);
1315 }
1316
1317 // Make a step iterating over the class hierarchy under the root class.
1318 // Skips subclasses if requested.
1319 void next();
1320
1321 Klass* klass() {
1322 assert(!done(), "sanity");
1323 return _current;
1324 }
1325
1326 // Skip subclasses of the current class.
1327 void skip_subclasses() {
1328 _visit_subclasses = false;
1329 }
1330 };
1331
1332 #endif // SHARE_OOPS_INSTANCEKLASS_HPP