1 /*
2 * Copyright 1997-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25 // An instanceKlass is the VM level representation of a Java class.
26 // It contains all information needed for at class at execution runtime.
27
28 // instanceKlass layout:
29 // [header ] klassOop
30 // [klass pointer ] klassOop
31 // [C++ vtbl pointer ] Klass
32 // [subtype cache ] Klass
33 // [instance size ] Klass
34 // [java mirror ] Klass
35 // [super ] Klass
36 // [access_flags ] Klass
37 // [name ] Klass
38 // [first subklass ] Klass
39 // [next sibling ] Klass
40 // [array klasses ]
41 // [methods ]
42 // [local interfaces ]
43 // [transitive interfaces ]
44 // [number of implementors ]
45 // [implementors ] klassOop[2]
46 // [fields ]
47 // [constants ]
48 // [class loader ]
49 // [protection domain ]
50 // [signers ]
51 // [source file name ]
52 // [inner classes ]
53 // [static field size ]
54 // [nonstatic field size ]
55 // [static oop fields size ]
56 // [nonstatic oop maps size ]
57 // [has finalize method ]
58 // [deoptimization mark bit ]
59 // [initialization state ]
60 // [initializing thread ]
61 // [Java vtable length ]
62 // [oop map cache (stack maps) ]
63 // [EMBEDDED Java vtable ] size in words = vtable_len
64 // [EMBEDDED static oop fields ] size in words = static_oop_fields_size
65 // [ static non-oop fields ] size in words = static_field_size - static_oop_fields_size
66 // [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
67 //
68 // The embedded nonstatic oop-map blocks are short pairs (offset, length) indicating
69 // where oops are located in instances of this klass.
70
71
72 // forward declaration for class -- see below for definition
73 class SuperTypeClosure;
74 class OopMapBlock;
75 class JNIid;
76 class jniIdMapBase;
77 class BreakpointInfo;
78 class fieldDescriptor;
79 class DepChange;
80 class nmethodBucket;
81 class PreviousVersionNode;
82 class JvmtiCachedClassFieldMap;
83
84 // This is used in iterators below.
85 class FieldClosure: public StackObj {
86 public:
87 virtual void do_field(fieldDescriptor* fd) = 0;
88 };
89
90 #ifndef PRODUCT
91 // Print fields.
92 // If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields.
93 class FieldPrinter: public FieldClosure {
94 oop _obj;
95 outputStream* _st;
96 public:
97 FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {}
98 void do_field(fieldDescriptor* fd);
99 };
100 #endif // !PRODUCT
101
102 class instanceKlass: public Klass {
103 friend class VMStructs;
104 public:
105 // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
106 // of the class loading & initialization procedure, and the use of the states.
107 enum ClassState {
108 unparsable_by_gc = 0, // object is not yet parsable by gc. Value of _init_state at object allocation.
109 allocated, // allocated (but not yet linked)
110 loaded, // loaded and inserted in class hierarchy (but not linked yet)
111 linked, // successfully linked/verified (but not initialized yet)
112 being_initialized, // currently running class initializer
113 fully_initialized, // initialized (successfull final state)
114 initialization_error // error happened during initialization
115 };
116
117 public:
118 oop* oop_block_beg() const { return adr_array_klasses(); }
119 oop* oop_block_end() const { return adr_methods_default_annotations() + 1; }
120
121 enum {
122 implementors_limit = 2 // how many implems can we track?
123 };
124
125 protected:
126 //
127 // The oop block. See comment in klass.hpp before making changes.
128 //
129
130 // Array classes holding elements of this class.
131 klassOop _array_klasses;
132 // Method array.
133 objArrayOop _methods;
134 // Int array containing the original order of method in the class file (for
135 // JVMTI).
136 typeArrayOop _method_ordering;
137 // Interface (klassOops) this class declares locally to implement.
138 objArrayOop _local_interfaces;
139 // Interface (klassOops) this class implements transitively.
140 objArrayOop _transitive_interfaces;
141 // Instance and static variable information, 5-tuples of shorts [access, name
142 // index, sig index, initval index, offset].
143 typeArrayOop _fields;
144 // Constant pool for this class.
145 constantPoolOop _constants;
146 // Class loader used to load this class, NULL if VM loader used.
147 oop _class_loader;
148 // Protection domain.
149 oop _protection_domain;
150 // Class signers.
151 objArrayOop _signers;
152 // Name of source file containing this klass, NULL if not specified.
153 symbolOop _source_file_name;
154 // the source debug extension for this klass, NULL if not specified.
155 symbolOop _source_debug_extension;
156 // inner_classes attribute.
157 typeArrayOop _inner_classes;
158 // Implementors of this interface (not valid if it overflows)
159 klassOop _implementors[implementors_limit];
160 // Generic signature, or null if none.
161 symbolOop _generic_signature;
162 // Annotations for this class, or null if none.
163 typeArrayOop _class_annotations;
164 // Annotation objects (byte arrays) for fields, or null if no annotations.
165 // Indices correspond to entries (not indices) in fields array.
166 objArrayOop _fields_annotations;
167 // Annotation objects (byte arrays) for methods, or null if no annotations.
168 // Index is the idnum, which is initially the same as the methods array index.
169 objArrayOop _methods_annotations;
170 // Annotation objects (byte arrays) for methods' parameters, or null if no
171 // such annotations.
172 // Index is the idnum, which is initially the same as the methods array index.
173 objArrayOop _methods_parameter_annotations;
174 // Annotation objects (byte arrays) for methods' default values, or null if no
175 // such annotations.
176 // Index is the idnum, which is initially the same as the methods array index.
177 objArrayOop _methods_default_annotations;
178
179 //
180 // End of the oop block.
181 //
182
183 // Number of heapOopSize words used by non-static fields in this klass
184 // (including inherited fields but after header_size()).
185 int _nonstatic_field_size;
186 int _static_field_size; // number words used by static fields (oop and non-oop) in this klass
187 int _static_oop_field_size;// number of static oop fields in this klass
188 int _nonstatic_oop_map_size;// number of nonstatic oop-map blocks allocated at end of this klass
189 bool _is_marked_dependent; // used for marking during flushing and deoptimization
190 bool _rewritten; // methods rewritten.
191 bool _has_nonstatic_fields; // for sizing with UseCompressedOops
192 u2 _minor_version; // minor version number of class file
193 u2 _major_version; // major version number of class file
194 ClassState _init_state; // state of class
195 Thread* _init_thread; // Pointer to current thread doing initialization (to handle recusive initialization)
196 int _vtable_len; // length of Java vtable (in words)
197 int _itable_len; // length of Java itable (in words)
198 ReferenceType _reference_type; // reference type
199 OopMapCache* volatile _oop_map_cache; // OopMapCache for all methods in the klass (allocated lazily)
200 JNIid* _jni_ids; // First JNI identifier for static fields in this class
201 jmethodID* _methods_jmethod_ids; // jmethodIDs corresponding to method_idnum, or NULL if none
202 int* _methods_cached_itable_indices; // itable_index cache for JNI invoke corresponding to methods idnum, or NULL
203 nmethodBucket* _dependencies; // list of dependent nmethods
204 nmethod* _osr_nmethods_head; // Head of list of on-stack replacement nmethods for this class
205 BreakpointInfo* _breakpoints; // bpt lists, managed by methodOop
206 int _nof_implementors; // No of implementors of this interface (zero if not an interface)
207 // Array of interesting part(s) of the previous version(s) of this
208 // instanceKlass. See PreviousVersionWalker below.
209 GrowableArray<PreviousVersionNode *>* _previous_versions;
210 u2 _enclosing_method_class_index; // Constant pool index for class of enclosing method, or 0 if none
211 u2 _enclosing_method_method_index; // Constant pool index for name and type of enclosing method, or 0 if none
212 // JVMTI fields can be moved to their own structure - see 6315920
213 unsigned char * _cached_class_file_bytes; // JVMTI: cached class file, before retransformable agent modified it in CFLH
214 jint _cached_class_file_len; // JVMTI: length of above
215 JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration
216 volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change
217
218 // embedded Java vtable follows here
219 // embedded Java itables follows here
220 // embedded static fields follows here
221 // embedded nonstatic oop-map blocks follows here
222
223 friend class instanceKlassKlass;
224 friend class SystemDictionary;
225
226 public:
227 bool has_nonstatic_fields() const { return _has_nonstatic_fields; }
228 void set_has_nonstatic_fields(bool b) { _has_nonstatic_fields = b; }
229
230 // field sizes
231 int nonstatic_field_size() const { return _nonstatic_field_size; }
232 void set_nonstatic_field_size(int size) { _nonstatic_field_size = size; }
233
234 int static_field_size() const { return _static_field_size; }
235 void set_static_field_size(int size) { _static_field_size = size; }
236
237 int static_oop_field_size() const { return _static_oop_field_size; }
238 void set_static_oop_field_size(int size) { _static_oop_field_size = size; }
239
240 // Java vtable
241 int vtable_length() const { return _vtable_len; }
242 void set_vtable_length(int len) { _vtable_len = len; }
243
244 // Java itable
245 int itable_length() const { return _itable_len; }
246 void set_itable_length(int len) { _itable_len = len; }
247
248 // array klasses
249 klassOop array_klasses() const { return _array_klasses; }
250 void set_array_klasses(klassOop k) { oop_store_without_check((oop*) &_array_klasses, (oop) k); }
251
252 // methods
253 objArrayOop methods() const { return _methods; }
254 void set_methods(objArrayOop a) { oop_store_without_check((oop*) &_methods, (oop) a); }
255 methodOop method_with_idnum(int idnum);
256
257 // method ordering
258 typeArrayOop method_ordering() const { return _method_ordering; }
259 void set_method_ordering(typeArrayOop m) { oop_store_without_check((oop*) &_method_ordering, (oop) m); }
260
261 // interfaces
262 objArrayOop local_interfaces() const { return _local_interfaces; }
263 void set_local_interfaces(objArrayOop a) { oop_store_without_check((oop*) &_local_interfaces, (oop) a); }
264 objArrayOop transitive_interfaces() const { return _transitive_interfaces; }
265 void set_transitive_interfaces(objArrayOop a) { oop_store_without_check((oop*) &_transitive_interfaces, (oop) a); }
266
267 // fields
268 // Field info extracted from the class file and stored
269 // as an array of 7 shorts
270 enum FieldOffset {
271 access_flags_offset = 0,
272 name_index_offset = 1,
273 signature_index_offset = 2,
274 initval_index_offset = 3,
275 low_offset = 4,
276 high_offset = 5,
277 generic_signature_offset = 6,
278 next_offset = 7
279 };
280
281 typeArrayOop fields() const { return _fields; }
282 int offset_from_fields( int index ) const {
283 return build_int_from_shorts( fields()->ushort_at(index + low_offset),
284 fields()->ushort_at(index + high_offset) );
285 }
286
287 void set_fields(typeArrayOop f) { oop_store_without_check((oop*) &_fields, (oop) f); }
288
289 // inner classes
290 typeArrayOop inner_classes() const { return _inner_classes; }
291 void set_inner_classes(typeArrayOop f) { oop_store_without_check((oop*) &_inner_classes, (oop) f); }
292
293 enum InnerClassAttributeOffset {
294 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
295 inner_class_inner_class_info_offset = 0,
296 inner_class_outer_class_info_offset = 1,
297 inner_class_inner_name_offset = 2,
298 inner_class_access_flags_offset = 3,
299 inner_class_next_offset = 4
300 };
301
302 // package
303 bool is_same_class_package(klassOop class2);
304 bool is_same_class_package(oop classloader2, symbolOop classname2);
305 static bool is_same_class_package(oop class_loader1, symbolOop class_name1, oop class_loader2, symbolOop class_name2);
306
307 // initialization state
308 bool is_loaded() const { return _init_state >= loaded; }
309 bool is_linked() const { return _init_state >= linked; }
310 bool is_initialized() const { return _init_state == fully_initialized; }
311 bool is_not_initialized() const { return _init_state < being_initialized; }
312 bool is_being_initialized() const { return _init_state == being_initialized; }
313 bool is_in_error_state() const { return _init_state == initialization_error; }
314 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; }
315 int get_init_state() { return _init_state; } // Useful for debugging
316 bool is_rewritten() const { return _rewritten; }
317
318 // marking
319 bool is_marked_dependent() const { return _is_marked_dependent; }
320 void set_is_marked_dependent(bool value) { _is_marked_dependent = value; }
321
322 // initialization (virtuals from Klass)
323 bool should_be_initialized() const; // means that initialize should be called
324 void initialize(TRAPS);
325 void link_class(TRAPS);
326 bool link_class_or_fail(TRAPS); // returns false on failure
327 void unlink_class();
328 void rewrite_class(TRAPS);
329 methodOop class_initializer();
330
331 // set the class to initialized if no static initializer is present
332 void eager_initialize(Thread *thread);
333
334 // reference type
335 ReferenceType reference_type() const { return _reference_type; }
336 void set_reference_type(ReferenceType t) { _reference_type = t; }
337
338 // find local field, returns true if found
339 bool find_local_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const;
340 // find field in direct superinterfaces, returns the interface in which the field is defined
341 klassOop find_interface_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const;
342 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
343 klassOop find_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const;
344 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
345 klassOop find_field(symbolOop name, symbolOop sig, bool is_static, fieldDescriptor* fd) const;
346
347 // find a non-static or static field given its offset within the class.
348 bool contains_field_offset(int offset) {
349 return instanceOopDesc::contains_field_offset(offset, nonstatic_field_size());
350 }
351
352 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
353 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
354
355 // find a local method (returns NULL if not found)
356 methodOop find_method(symbolOop name, symbolOop signature) const;
357 static methodOop find_method(objArrayOop methods, symbolOop name, symbolOop signature);
358
359 // lookup operation (returns NULL if not found)
360 methodOop uncached_lookup_method(symbolOop name, symbolOop signature) const;
361
362 // lookup a method in all the interfaces that this class implements
363 // (returns NULL if not found)
364 methodOop lookup_method_in_all_interfaces(symbolOop name, symbolOop signature) const;
365
366 // constant pool
367 constantPoolOop constants() const { return _constants; }
368 void set_constants(constantPoolOop c) { oop_store_without_check((oop*) &_constants, (oop) c); }
369
370 // class loader
371 oop class_loader() const { return _class_loader; }
372 void set_class_loader(oop l) { oop_store((oop*) &_class_loader, l); }
373
374 // protection domain
375 oop protection_domain() { return _protection_domain; }
376 void set_protection_domain(oop pd) { oop_store((oop*) &_protection_domain, pd); }
377
378 // signers
379 objArrayOop signers() const { return _signers; }
380 void set_signers(objArrayOop s) { oop_store((oop*) &_signers, oop(s)); }
381
382 // source file name
383 symbolOop source_file_name() const { return _source_file_name; }
384 void set_source_file_name(symbolOop n) { oop_store_without_check((oop*) &_source_file_name, (oop) n); }
385
386 // minor and major version numbers of class file
387 u2 minor_version() const { return _minor_version; }
388 void set_minor_version(u2 minor_version) { _minor_version = minor_version; }
389 u2 major_version() const { return _major_version; }
390 void set_major_version(u2 major_version) { _major_version = major_version; }
391
392 // source debug extension
393 symbolOop source_debug_extension() const { return _source_debug_extension; }
394 void set_source_debug_extension(symbolOop n){ oop_store_without_check((oop*) &_source_debug_extension, (oop) n); }
395
396 // nonstatic oop-map blocks
397 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
398 void set_nonstatic_oop_map_size(int size) { _nonstatic_oop_map_size = size; }
399
400 // RedefineClasses() support for previous versions:
401 void add_previous_version(instanceKlassHandle ikh, BitMap *emcp_methods,
402 int emcp_method_count);
403 bool has_previous_version() const;
404 void init_previous_versions() {
405 _previous_versions = NULL;
406 }
407 GrowableArray<PreviousVersionNode *>* previous_versions() const {
408 return _previous_versions;
409 }
410
411 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
412 void set_cached_class_file(unsigned char *class_file_bytes,
413 jint class_file_len) { _cached_class_file_len = class_file_len;
414 _cached_class_file_bytes = class_file_bytes; }
415 jint get_cached_class_file_len() { return _cached_class_file_len; }
416 unsigned char * get_cached_class_file_bytes() { return _cached_class_file_bytes; }
417
418 // JVMTI: Support for caching of field indices, types, and offsets
419 void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
420 _jvmti_cached_class_field_map = descriptor;
421 }
422 JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
423 return _jvmti_cached_class_field_map;
424 }
425
426 // for adding methods, constMethodOopDesc::UNSET_IDNUM means no more ids available
427 inline u2 next_method_idnum();
428 void set_initial_method_idnum(u2 value) { _idnum_allocated_count = value; }
429
430 // generics support
431 symbolOop generic_signature() const { return _generic_signature; }
432 void set_generic_signature(symbolOop sig) { oop_store_without_check((oop*)&_generic_signature, (oop)sig); }
433 u2 enclosing_method_class_index() const { return _enclosing_method_class_index; }
434 u2 enclosing_method_method_index() const { return _enclosing_method_method_index; }
435 void set_enclosing_method_indices(u2 class_index,
436 u2 method_index) { _enclosing_method_class_index = class_index;
437 _enclosing_method_method_index = method_index; }
438
439 // jmethodID support
440 static jmethodID get_jmethod_id(instanceKlassHandle ik_h, size_t idnum,
441 jmethodID new_id, jmethodID* new_jmeths);
442 static jmethodID jmethod_id_for_impl(instanceKlassHandle ik_h, methodHandle method_h);
443 jmethodID jmethod_id_or_null(methodOop method);
444
445 // cached itable index support
446 void set_cached_itable_index(size_t idnum, int index);
447 int cached_itable_index(size_t idnum);
448
449 // annotations support
450 typeArrayOop class_annotations() const { return _class_annotations; }
451 objArrayOop fields_annotations() const { return _fields_annotations; }
452 objArrayOop methods_annotations() const { return _methods_annotations; }
453 objArrayOop methods_parameter_annotations() const { return _methods_parameter_annotations; }
454 objArrayOop methods_default_annotations() const { return _methods_default_annotations; }
455 void set_class_annotations(typeArrayOop md) { oop_store_without_check((oop*)&_class_annotations, (oop)md); }
456 void set_fields_annotations(objArrayOop md) { set_annotations(md, &_fields_annotations); }
457 void set_methods_annotations(objArrayOop md) { set_annotations(md, &_methods_annotations); }
458 void set_methods_parameter_annotations(objArrayOop md) { set_annotations(md, &_methods_parameter_annotations); }
459 void set_methods_default_annotations(objArrayOop md) { set_annotations(md, &_methods_default_annotations); }
460 typeArrayOop get_method_annotations_of(int idnum)
461 { return get_method_annotations_from(idnum, _methods_annotations); }
462 typeArrayOop get_method_parameter_annotations_of(int idnum)
463 { return get_method_annotations_from(idnum, _methods_parameter_annotations); }
464 typeArrayOop get_method_default_annotations_of(int idnum)
465 { return get_method_annotations_from(idnum, _methods_default_annotations); }
466 void set_method_annotations_of(int idnum, typeArrayOop anno)
467 { set_methods_annotations_of(idnum, anno, &_methods_annotations); }
468 void set_method_parameter_annotations_of(int idnum, typeArrayOop anno)
469 { set_methods_annotations_of(idnum, anno, &_methods_annotations); }
470 void set_method_default_annotations_of(int idnum, typeArrayOop anno)
471 { set_methods_annotations_of(idnum, anno, &_methods_annotations); }
472
473 // allocation
474 DEFINE_ALLOCATE_PERMANENT(instanceKlass);
475 instanceOop allocate_instance(TRAPS);
476 instanceOop allocate_permanent_instance(TRAPS);
477
478 // additional member function to return a handle
479 instanceHandle allocate_instance_handle(TRAPS) { return instanceHandle(THREAD, allocate_instance(THREAD)); }
480
481 objArrayOop allocate_objArray(int n, int length, TRAPS);
482 // Helper function
483 static instanceOop register_finalizer(instanceOop i, TRAPS);
484
485 // Check whether reflection/jni/jvm code is allowed to instantiate this class;
486 // if not, throw either an Error or an Exception.
487 virtual void check_valid_for_instantiation(bool throwError, TRAPS);
488
489 // initialization
490 void call_class_initializer(TRAPS);
491 void set_initialization_state_and_notify(ClassState state, TRAPS);
492
493 // OopMapCache support
494 OopMapCache* oop_map_cache() { return _oop_map_cache; }
495 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
496 void mask_for(methodHandle method, int bci, InterpreterOopMap* entry);
497
498 // JNI identifier support (for static fields - for jni performance)
499 JNIid* jni_ids() { return _jni_ids; }
500 void set_jni_ids(JNIid* ids) { _jni_ids = ids; }
501 JNIid* jni_id_for(int offset);
502
503 // maintenance of deoptimization dependencies
504 int mark_dependent_nmethods(DepChange& changes);
505 void add_dependent_nmethod(nmethod* nm);
506 void remove_dependent_nmethod(nmethod* nm);
507
508 // On-stack replacement support
509 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; };
510 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; };
511 void add_osr_nmethod(nmethod* n);
512 void remove_osr_nmethod(nmethod* n);
513 nmethod* lookup_osr_nmethod(const methodOop m, int bci) const;
514
515 // Breakpoint support (see methods on methodOop for details)
516 BreakpointInfo* breakpoints() const { return _breakpoints; };
517 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
518
519 // support for stub routines
520 static int init_state_offset_in_bytes() { return offset_of(instanceKlass, _init_state); }
521 static int init_thread_offset_in_bytes() { return offset_of(instanceKlass, _init_thread); }
522
523 // subclass/subinterface checks
524 bool implements_interface(klassOop k) const;
525
526 // Access to implementors of an interface. We only store the count
527 // of implementors, and in case, there are only a few
528 // implementors, we store them in a short list.
529 // This accessor returns NULL if we walk off the end of the list.
530 klassOop implementor(int i) const {
531 return (i < implementors_limit)? _implementors[i]: (klassOop) NULL;
532 }
533 int nof_implementors() const { return _nof_implementors; }
534 void add_implementor(klassOop k); // k is a new class that implements this interface
535 void init_implementor(); // initialize
536
537 // link this class into the implementors list of every interface it implements
538 void process_interfaces(Thread *thread);
539
540 // virtual operations from Klass
541 bool is_leaf_class() const { return _subklass == NULL; }
542 objArrayOop compute_secondary_supers(int num_extra_slots, TRAPS);
543 bool compute_is_subtype_of(klassOop k);
544 bool can_be_primary_super_slow() const;
545 klassOop java_super() const { return super(); }
546 int oop_size(oop obj) const { return size_helper(); }
547 int klass_oop_size() const { return object_size(); }
548 bool oop_is_instance_slow() const { return true; }
549
550 // Iterators
551 void do_local_static_fields(FieldClosure* cl);
552 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
553 void do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS);
554
555 void methods_do(void f(methodOop method));
556 void array_klasses_do(void f(klassOop k));
557 void with_array_klasses_do(void f(klassOop k));
558 bool super_types_do(SuperTypeClosure* blk);
559
560 // Casting from klassOop
561 static instanceKlass* cast(klassOop k) {
562 Klass* kp = k->klass_part();
563 assert(kp->null_vtbl() || kp->oop_is_instance_slow(), "cast to instanceKlass");
564 return (instanceKlass*) kp;
565 }
566
567 // Sizing (in words)
568 static int header_size() { return align_object_offset(oopDesc::header_size() + sizeof(instanceKlass)/HeapWordSize); }
569 int object_size() const { return object_size(align_object_offset(vtable_length()) + align_object_offset(itable_length()) + static_field_size() + nonstatic_oop_map_size()); }
570 static int vtable_start_offset() { return header_size(); }
571 static int vtable_length_offset() { return oopDesc::header_size() + offset_of(instanceKlass, _vtable_len) / HeapWordSize; }
572 static int object_size(int extra) { return align_object_size(header_size() + extra); }
573
574 intptr_t* start_of_vtable() const { return ((intptr_t*)as_klassOop()) + vtable_start_offset(); }
575 intptr_t* start_of_itable() const { return start_of_vtable() + align_object_offset(vtable_length()); }
576 int itable_offset_in_words() const { return start_of_itable() - (intptr_t*)as_klassOop(); }
577
578 // Static field offset is an offset into the Heap, should be converted by
579 // based on UseCompressedOop for traversal
580 HeapWord* start_of_static_fields() const {
581 return (HeapWord*)(start_of_itable() + align_object_offset(itable_length()));
582 }
583
584 intptr_t* end_of_itable() const { return start_of_itable() + itable_length(); }
585
586 int offset_of_static_fields() const {
587 return (intptr_t)start_of_static_fields() - (intptr_t)as_klassOop();
588 }
589
590 OopMapBlock* start_of_nonstatic_oop_maps() const {
591 return (OopMapBlock*) (start_of_static_fields() + static_field_size());
592 }
593
594 // Allocation profiling support
595 juint alloc_size() const { return _alloc_count * size_helper(); }
596 void set_alloc_size(juint n) {}
597
598 // Use this to return the size of an instance in heap words:
599 int size_helper() const {
600 return layout_helper_to_size_helper(layout_helper());
601 }
602
603 // This bit is initialized in classFileParser.cpp.
604 // It is false under any of the following conditions:
605 // - the class is abstract (including any interface)
606 // - the class has a finalizer (if !RegisterFinalizersAtInit)
607 // - the class size is larger than FastAllocateSizeLimit
608 // - the class is java/lang/Class, which cannot be allocated directly
609 bool can_be_fastpath_allocated() const {
610 return !layout_helper_needs_slow_path(layout_helper());
611 }
612
613 // Java vtable/itable
614 klassVtable* vtable() const; // return new klassVtable wrapper
615 inline methodOop method_at_vtable(int index);
616 klassItable* itable() const; // return new klassItable wrapper
617 methodOop method_at_itable(klassOop holder, int index, TRAPS);
618
619 // Garbage collection
620 void oop_follow_contents(oop obj);
621 void follow_static_fields();
622 void adjust_static_fields();
623 int oop_adjust_pointers(oop obj);
624 bool object_is_parsable() const { return _init_state != unparsable_by_gc; }
625 // Value of _init_state must be zero (unparsable_by_gc) when klass field is set.
626
627 void follow_weak_klass_links(
628 BoolObjectClosure* is_alive, OopClosure* keep_alive);
629 void release_C_heap_structures();
630
631 // Parallel Scavenge and Parallel Old
632 PARALLEL_GC_DECLS
633
634 #ifndef SERIALGC
635 // Parallel Scavenge
636 void copy_static_fields(PSPromotionManager* pm);
637 void push_static_fields(PSPromotionManager* pm);
638
639 // Parallel Old
640 void follow_static_fields(ParCompactionManager* cm);
641 void copy_static_fields(ParCompactionManager* cm);
642 void update_static_fields();
643 void update_static_fields(HeapWord* beg_addr, HeapWord* end_addr);
644 #endif // SERIALGC
645
646 // Naming
647 char* signature_name() const;
648
649 // Iterators
650 int oop_oop_iterate(oop obj, OopClosure* blk) {
651 return oop_oop_iterate_v(obj, blk);
652 }
653
654 int oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr) {
655 return oop_oop_iterate_v_m(obj, blk, mr);
656 }
657
658 #define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix) \
659 int oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk); \
660 int oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk, \
661 MemRegion mr);
662
663 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL)
664 ALL_OOP_OOP_ITERATE_CLOSURES_3(InstanceKlass_OOP_OOP_ITERATE_DECL)
665
666 void iterate_static_fields(OopClosure* closure);
667 void iterate_static_fields(OopClosure* closure, MemRegion mr);
668
669 private:
670 // initialization state
671 #ifdef ASSERT
672 void set_init_state(ClassState state);
673 #else
674 void set_init_state(ClassState state) { _init_state = state; }
675 #endif
676 void set_rewritten() { _rewritten = true; }
677 void set_init_thread(Thread *thread) { _init_thread = thread; }
678
679 u2 idnum_allocated_count() const { return _idnum_allocated_count; }
680 jmethodID* methods_jmethod_ids_acquire() const
681 { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); }
682 void release_set_methods_jmethod_ids(jmethodID* jmeths)
683 { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); }
684
685 int* methods_cached_itable_indices_acquire() const
686 { return (int*)OrderAccess::load_ptr_acquire(&_methods_cached_itable_indices); }
687 void release_set_methods_cached_itable_indices(int* indices)
688 { OrderAccess::release_store_ptr(&_methods_cached_itable_indices, indices); }
689
690 inline typeArrayOop get_method_annotations_from(int idnum, objArrayOop annos);
691 void set_annotations(objArrayOop md, objArrayOop* md_p) { oop_store_without_check((oop*)md_p, (oop)md); }
692 void set_methods_annotations_of(int idnum, typeArrayOop anno, objArrayOop* md_p);
693
694 // Offsets for memory management
695 oop* adr_array_klasses() const { return (oop*)&this->_array_klasses;}
696 oop* adr_methods() const { return (oop*)&this->_methods;}
697 oop* adr_method_ordering() const { return (oop*)&this->_method_ordering;}
698 oop* adr_local_interfaces() const { return (oop*)&this->_local_interfaces;}
699 oop* adr_transitive_interfaces() const { return (oop*)&this->_transitive_interfaces;}
700 oop* adr_fields() const { return (oop*)&this->_fields;}
701 oop* adr_constants() const { return (oop*)&this->_constants;}
702 oop* adr_class_loader() const { return (oop*)&this->_class_loader;}
703 oop* adr_protection_domain() const { return (oop*)&this->_protection_domain;}
704 oop* adr_signers() const { return (oop*)&this->_signers;}
705 oop* adr_source_file_name() const { return (oop*)&this->_source_file_name;}
706 oop* adr_source_debug_extension() const { return (oop*)&this->_source_debug_extension;}
707 oop* adr_inner_classes() const { return (oop*)&this->_inner_classes;}
708 oop* adr_implementors() const { return (oop*)&this->_implementors[0];}
709 oop* adr_generic_signature() const { return (oop*)&this->_generic_signature;}
710 oop* adr_methods_jmethod_ids() const { return (oop*)&this->_methods_jmethod_ids;}
711 oop* adr_methods_cached_itable_indices() const { return (oop*)&this->_methods_cached_itable_indices;}
712 oop* adr_class_annotations() const { return (oop*)&this->_class_annotations;}
713 oop* adr_fields_annotations() const { return (oop*)&this->_fields_annotations;}
714 oop* adr_methods_annotations() const { return (oop*)&this->_methods_annotations;}
715 oop* adr_methods_parameter_annotations() const { return (oop*)&this->_methods_parameter_annotations;}
716 oop* adr_methods_default_annotations() const { return (oop*)&this->_methods_default_annotations;}
717
718 // Static methods that are used to implement member methods where an exposed this pointer
719 // is needed due to possible GCs
720 static bool link_class_impl (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
721 static bool verify_code (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
722 static void initialize_impl (instanceKlassHandle this_oop, TRAPS);
723 static void eager_initialize_impl (instanceKlassHandle this_oop);
724 static void set_initialization_state_and_notify_impl (instanceKlassHandle this_oop, ClassState state, TRAPS);
725 static void call_class_initializer_impl (instanceKlassHandle this_oop, TRAPS);
726 static klassOop array_klass_impl (instanceKlassHandle this_oop, bool or_null, int n, TRAPS);
727 static void do_local_static_fields_impl (instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS);
728 /* jni_id_for_impl for jfieldID only */
729 static JNIid* jni_id_for_impl (instanceKlassHandle this_oop, int offset);
730
731 // Returns the array class for the n'th dimension
732 klassOop array_klass_impl(bool or_null, int n, TRAPS);
733
734 // Returns the array class with this class as element type
735 klassOop array_klass_impl(bool or_null, TRAPS);
736
737 public:
738 // sharing support
739 virtual void remove_unshareable_info();
740 void field_names_and_sigs_iterate(OopClosure* closure);
741
742 // jvm support
743 jint compute_modifier_flags(TRAPS) const;
744
745 public:
746 // JVMTI support
747 jint jvmti_class_status() const;
748
749 #ifndef PRODUCT
750 public:
751 // Printing
752 void oop_print_on (oop obj, outputStream* st);
753 void oop_print_value_on(oop obj, outputStream* st);
754
755 void print_dependent_nmethods(bool verbose = false);
756 bool is_dependent_nmethod(nmethod* nm);
757 #endif
758
759 public:
760 // Verification
761 const char* internal_name() const;
762 void oop_verify_on(oop obj, outputStream* st);
763
764 #ifndef PRODUCT
765 static void verify_class_klass_nonstatic_oop_maps(klassOop k) PRODUCT_RETURN;
766 #endif
767 };
768
769 inline methodOop instanceKlass::method_at_vtable(int index) {
770 #ifndef PRODUCT
771 assert(index >= 0, "valid vtable index");
772 if (DebugVtables) {
773 verify_vtable_index(index);
774 }
775 #endif
776 vtableEntry* ve = (vtableEntry*)start_of_vtable();
777 return ve[index].method();
778 }
779
780 inline typeArrayOop instanceKlass::get_method_annotations_from(int idnum, objArrayOop annos) {
781 if (annos == NULL || annos->length() <= idnum) {
782 return NULL;
783 }
784 return typeArrayOop(annos->obj_at(idnum));
785 }
786
787 // for adding methods
788 // UNSET_IDNUM return means no more ids available
789 inline u2 instanceKlass::next_method_idnum() {
790 if (_idnum_allocated_count == constMethodOopDesc::MAX_IDNUM) {
791 return constMethodOopDesc::UNSET_IDNUM; // no more ids available
792 } else {
793 return _idnum_allocated_count++;
794 }
795 }
796
797
798 // ValueObjs embedded in klass. Describes where oops are located in instances of this klass.
799
800 class OopMapBlock VALUE_OBJ_CLASS_SPEC {
801 private:
802 jushort _offset; // Offset of first oop in oop-map block
803 jushort _length; // Length of oop-map block
804 public:
805 // Accessors
806 jushort offset() const { return _offset; }
807 void set_offset(jushort offset) { _offset = offset; }
808
809 jushort length() const { return _length; }
810 void set_length(jushort length) { _length = length; }
811 };
812
813 /* JNIid class for jfieldIDs only */
814 class JNIid: public CHeapObj {
815 friend class VMStructs;
816 private:
817 klassOop _holder;
818 JNIid* _next;
819 int _offset;
820 #ifdef ASSERT
821 bool _is_static_field_id;
822 #endif
823
824 public:
825 // Accessors
826 klassOop holder() const { return _holder; }
827 int offset() const { return _offset; }
828 JNIid* next() { return _next; }
829 // Constructor
830 JNIid(klassOop holder, int offset, JNIid* next);
831 // Identifier lookup
832 JNIid* find(int offset);
833
834 // Garbage collection support
835 oop* holder_addr() { return (oop*)&_holder; }
836 void oops_do(OopClosure* f);
837 static void deallocate(JNIid* id);
838 // Debugging
839 #ifdef ASSERT
840 bool is_static_field_id() const { return _is_static_field_id; }
841 void set_is_static_field_id() { _is_static_field_id = true; }
842 #endif
843 void verify(klassOop holder);
844 };
845
846
847 // If breakpoints are more numerous than just JVMTI breakpoints,
848 // consider compressing this data structure.
849 // It is currently a simple linked list defined in methodOop.hpp.
850
851 class BreakpointInfo;
852
853
854 // A collection point for interesting information about the previous
855 // version(s) of an instanceKlass. This class uses weak references to
856 // the information so that the information may be collected as needed
857 // by the system. If the information is shared, then a regular
858 // reference must be used because a weak reference would be seen as
859 // collectible. A GrowableArray of PreviousVersionNodes is attached
860 // to the instanceKlass as needed. See PreviousVersionWalker below.
861 class PreviousVersionNode : public CHeapObj {
862 private:
863 // A shared ConstantPool is never collected so we'll always have
864 // a reference to it so we can update items in the cache. We'll
865 // have a weak reference to a non-shared ConstantPool until all
866 // of the methods (EMCP or obsolete) have been collected; the
867 // non-shared ConstantPool becomes collectible at that point.
868 jobject _prev_constant_pool; // regular or weak reference
869 bool _prev_cp_is_weak; // true if not a shared ConstantPool
870
871 // If the previous version of the instanceKlass doesn't have any
872 // EMCP methods, then _prev_EMCP_methods will be NULL. If all the
873 // EMCP methods have been collected, then _prev_EMCP_methods can
874 // have a length of zero.
875 GrowableArray<jweak>* _prev_EMCP_methods;
876
877 public:
878 PreviousVersionNode(jobject prev_constant_pool, bool prev_cp_is_weak,
879 GrowableArray<jweak>* prev_EMCP_methods);
880 ~PreviousVersionNode();
881 jobject prev_constant_pool() const {
882 return _prev_constant_pool;
883 }
884 GrowableArray<jweak>* prev_EMCP_methods() const {
885 return _prev_EMCP_methods;
886 }
887 };
888
889
890 // A Handle-ized version of PreviousVersionNode.
891 class PreviousVersionInfo : public ResourceObj {
892 private:
893 constantPoolHandle _prev_constant_pool_handle;
894 // If the previous version of the instanceKlass doesn't have any
895 // EMCP methods, then _prev_EMCP_methods will be NULL. Since the
896 // methods cannot be collected while we hold a handle,
897 // _prev_EMCP_methods should never have a length of zero.
898 GrowableArray<methodHandle>* _prev_EMCP_method_handles;
899
900 public:
901 PreviousVersionInfo(PreviousVersionNode *pv_node);
902 ~PreviousVersionInfo();
903 constantPoolHandle prev_constant_pool_handle() const {
904 return _prev_constant_pool_handle;
905 }
906 GrowableArray<methodHandle>* prev_EMCP_method_handles() const {
907 return _prev_EMCP_method_handles;
908 }
909 };
910
911
912 // Helper object for walking previous versions. This helper cleans up
913 // the Handles that it allocates when the helper object is destroyed.
914 // The PreviousVersionInfo object returned by next_previous_version()
915 // is only valid until a subsequent call to next_previous_version() or
916 // the helper object is destroyed.
917 class PreviousVersionWalker : public StackObj {
918 private:
919 GrowableArray<PreviousVersionNode *>* _previous_versions;
920 int _current_index;
921 // Fields for cleaning up when we are done walking the previous versions:
922 // A HandleMark for the PreviousVersionInfo handles:
923 HandleMark _hm;
924
925 // It would be nice to have a ResourceMark field in this helper also,
926 // but the ResourceMark code says to be careful to delete handles held
927 // in GrowableArrays _before_ deleting the GrowableArray. Since we
928 // can't guarantee the order in which the fields are destroyed, we
929 // have to let the creator of the PreviousVersionWalker object do
930 // the right thing. Also, adding a ResourceMark here causes an
931 // include loop.
932
933 // A pointer to the current info object so we can handle the deletes.
934 PreviousVersionInfo * _current_p;
935
936 public:
937 PreviousVersionWalker(instanceKlass *ik);
938 ~PreviousVersionWalker();
939
940 // Return the interesting information for the next previous version
941 // of the klass. Returns NULL if there are no more previous versions.
942 PreviousVersionInfo* next_previous_version();
943 };