1 /*
2 * Copyright (c) 1997, 2016, 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 #include "precompiled.hpp"
26 #include "classfile/dictionary.hpp"
27 #include "classfile/javaClasses.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "gc/shared/collectedHeap.inline.hpp"
31 #include "memory/heapInspection.hpp"
32 #include "memory/metadataFactory.hpp"
33 #include "memory/oopFactory.hpp"
34 #include "memory/resourceArea.hpp"
35 #include "oops/instanceKlass.hpp"
36 #include "oops/klass.inline.hpp"
37 #include "oops/oop.inline.hpp"
38 #include "runtime/atomic.inline.hpp"
39 #include "runtime/orderAccess.inline.hpp"
40 #include "trace/traceMacros.hpp"
41 #include "utilities/macros.hpp"
42 #include "utilities/stack.inline.hpp"
43 #include "logging/log.hpp"
44 #if INCLUDE_ALL_GCS
45 #include "gc/g1/g1SATBCardTableModRefBS.hpp"
46 #endif // INCLUDE_ALL_GCS
47
48 void Klass::set_name(Symbol* n) {
49 _name = n;
50 if (_name != NULL) _name->increment_refcount();
51 }
52
53 bool Klass::is_subclass_of(const Klass* k) const {
54 // Run up the super chain and check
55 if (this == k) return true;
56
57 Klass* t = const_cast<Klass*>(this)->super();
58
59 while (t != NULL) {
60 if (t == k) return true;
61 t = t->super();
62 }
63 return false;
64 }
65
66 bool Klass::search_secondary_supers(Klass* k) const {
67 // Put some extra logic here out-of-line, before the search proper.
68 // This cuts down the size of the inline method.
69
70 // This is necessary, since I am never in my own secondary_super list.
71 if (this == k)
72 return true;
73 // Scan the array-of-objects for a match
74 int cnt = secondary_supers()->length();
75 for (int i = 0; i < cnt; i++) {
76 if (secondary_supers()->at(i) == k) {
77 ((Klass*)this)->set_secondary_super_cache(k);
78 return true;
79 }
80 }
81 return false;
82 }
83
84 // Return self, except for abstract classes with exactly 1
85 // implementor. Then return the 1 concrete implementation.
86 Klass *Klass::up_cast_abstract() {
87 Klass *r = this;
88 while( r->is_abstract() ) { // Receiver is abstract?
89 Klass *s = r->subklass(); // Check for exactly 1 subklass
90 if( !s || s->next_sibling() ) // Oops; wrong count; give up
91 return this; // Return 'this' as a no-progress flag
92 r = s; // Loop till find concrete class
93 }
94 return r; // Return the 1 concrete class
95 }
96
97 // Find LCA in class hierarchy
98 Klass *Klass::LCA( Klass *k2 ) {
99 Klass *k1 = this;
100 while( 1 ) {
101 if( k1->is_subtype_of(k2) ) return k2;
102 if( k2->is_subtype_of(k1) ) return k1;
103 k1 = k1->super();
104 k2 = k2->super();
105 }
106 }
107
108
109 void Klass::check_valid_for_instantiation(bool throwError, TRAPS) {
110 ResourceMark rm(THREAD);
111 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
112 : vmSymbols::java_lang_InstantiationException(), external_name());
113 }
114
115
116 void Klass::copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS) {
117 THROW(vmSymbols::java_lang_ArrayStoreException());
118 }
119
120
121 void Klass::initialize(TRAPS) {
122 ShouldNotReachHere();
123 }
124
125 bool Klass::compute_is_subtype_of(Klass* k) {
126 assert(k->is_klass(), "argument must be a class");
127 return is_subclass_of(k);
128 }
129
130 Klass* Klass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
131 #ifdef ASSERT
132 tty->print_cr("Error: find_field called on a klass oop."
133 " Likely error: reflection method does not correctly"
134 " wrap return value in a mirror object.");
135 #endif
136 ShouldNotReachHere();
137 return NULL;
138 }
139
140 Method* Klass::uncached_lookup_method(const Symbol* name, const Symbol* signature, OverpassLookupMode overpass_mode) const {
141 #ifdef ASSERT
142 tty->print_cr("Error: uncached_lookup_method called on a klass oop."
143 " Likely error: reflection method does not correctly"
144 " wrap return value in a mirror object.");
145 #endif
146 ShouldNotReachHere();
147 return NULL;
148 }
149
150 void* Klass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS) throw() {
151 return Metaspace::allocate(loader_data, word_size, /*read_only*/false,
152 MetaspaceObj::ClassType, THREAD);
153 }
154
155 // "Normal" instantiation is preceeded by a MetaspaceObj allocation
156 // which zeros out memory - calloc equivalent.
157 // The constructor is also used from init_self_patching_vtbl_list,
158 // which doesn't zero out the memory before calling the constructor.
159 // Need to set the _java_mirror field explicitly to not hit an assert that the field
160 // should be NULL before setting it.
161 Klass::Klass() : _prototype_header(markOopDesc::prototype()),
162 _shared_class_path_index(-1),
163 _java_mirror(NULL) {
164
165 _primary_supers[0] = this;
166 set_super_check_offset(in_bytes(primary_supers_offset()));
167 }
168
169 jint Klass::array_layout_helper(BasicType etype) {
170 assert(etype >= T_BOOLEAN && etype <= T_OBJECT, "valid etype");
171 // Note that T_ARRAY is not allowed here.
172 int hsize = arrayOopDesc::base_offset_in_bytes(etype);
173 int esize = type2aelembytes(etype);
174 bool isobj = (etype == T_OBJECT);
175 int tag = isobj ? _lh_array_tag_obj_value : _lh_array_tag_type_value;
176 int lh = array_layout_helper(tag, hsize, etype, exact_log2(esize));
177
178 assert(lh < (int)_lh_neutral_value, "must look like an array layout");
179 assert(layout_helper_is_array(lh), "correct kind");
180 assert(layout_helper_is_objArray(lh) == isobj, "correct kind");
181 assert(layout_helper_is_typeArray(lh) == !isobj, "correct kind");
182 assert(layout_helper_header_size(lh) == hsize, "correct decode");
183 assert(layout_helper_element_type(lh) == etype, "correct decode");
184 assert(1 << layout_helper_log2_element_size(lh) == esize, "correct decode");
185
186 return lh;
187 }
188
189 bool Klass::can_be_primary_super_slow() const {
190 if (super() == NULL)
191 return true;
192 else if (super()->super_depth() >= primary_super_limit()-1)
193 return false;
194 else
195 return true;
196 }
197
198 void Klass::initialize_supers(Klass* k, TRAPS) {
199 if (FastSuperclassLimit == 0) {
200 // None of the other machinery matters.
201 set_super(k);
202 return;
203 }
204 if (k == NULL) {
205 set_super(NULL);
206 _primary_supers[0] = this;
207 assert(super_depth() == 0, "Object must already be initialized properly");
208 } else if (k != super() || k == SystemDictionary::Object_klass()) {
209 assert(super() == NULL || super() == SystemDictionary::Object_klass(),
210 "initialize this only once to a non-trivial value");
211 set_super(k);
212 Klass* sup = k;
213 int sup_depth = sup->super_depth();
214 juint my_depth = MIN2(sup_depth + 1, (int)primary_super_limit());
215 if (!can_be_primary_super_slow())
216 my_depth = primary_super_limit();
217 for (juint i = 0; i < my_depth; i++) {
218 _primary_supers[i] = sup->_primary_supers[i];
219 }
220 Klass* *super_check_cell;
221 if (my_depth < primary_super_limit()) {
222 _primary_supers[my_depth] = this;
223 super_check_cell = &_primary_supers[my_depth];
224 } else {
225 // Overflow of the primary_supers array forces me to be secondary.
226 super_check_cell = &_secondary_super_cache;
227 }
228 set_super_check_offset((address)super_check_cell - (address) this);
229
230 #ifdef ASSERT
231 {
232 juint j = super_depth();
233 assert(j == my_depth, "computed accessor gets right answer");
234 Klass* t = this;
235 while (!t->can_be_primary_super()) {
236 t = t->super();
237 j = t->super_depth();
238 }
239 for (juint j1 = j+1; j1 < primary_super_limit(); j1++) {
240 assert(primary_super_of_depth(j1) == NULL, "super list padding");
241 }
242 while (t != NULL) {
243 assert(primary_super_of_depth(j) == t, "super list initialization");
244 t = t->super();
245 --j;
246 }
247 assert(j == (juint)-1, "correct depth count");
248 }
249 #endif
250 }
251
252 if (secondary_supers() == NULL) {
253 KlassHandle this_kh (THREAD, this);
254
255 // Now compute the list of secondary supertypes.
256 // Secondaries can occasionally be on the super chain,
257 // if the inline "_primary_supers" array overflows.
258 int extras = 0;
259 Klass* p;
260 for (p = super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
261 ++extras;
262 }
263
264 ResourceMark rm(THREAD); // need to reclaim GrowableArrays allocated below
265
266 // Compute the "real" non-extra secondaries.
267 GrowableArray<Klass*>* secondaries = compute_secondary_supers(extras);
268 if (secondaries == NULL) {
269 // secondary_supers set by compute_secondary_supers
270 return;
271 }
272
273 GrowableArray<Klass*>* primaries = new GrowableArray<Klass*>(extras);
274
275 for (p = this_kh->super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
276 int i; // Scan for overflow primaries being duplicates of 2nd'arys
277
278 // This happens frequently for very deeply nested arrays: the
279 // primary superclass chain overflows into the secondary. The
280 // secondary list contains the element_klass's secondaries with
281 // an extra array dimension added. If the element_klass's
282 // secondary list already contains some primary overflows, they
283 // (with the extra level of array-ness) will collide with the
284 // normal primary superclass overflows.
285 for( i = 0; i < secondaries->length(); i++ ) {
286 if( secondaries->at(i) == p )
287 break;
288 }
289 if( i < secondaries->length() )
290 continue; // It's a dup, don't put it in
291 primaries->push(p);
292 }
293 // Combine the two arrays into a metadata object to pack the array.
294 // The primaries are added in the reverse order, then the secondaries.
295 int new_length = primaries->length() + secondaries->length();
296 Array<Klass*>* s2 = MetadataFactory::new_array<Klass*>(
297 class_loader_data(), new_length, CHECK);
298 int fill_p = primaries->length();
299 for (int j = 0; j < fill_p; j++) {
300 s2->at_put(j, primaries->pop()); // add primaries in reverse order.
301 }
302 for( int j = 0; j < secondaries->length(); j++ ) {
303 s2->at_put(j+fill_p, secondaries->at(j)); // add secondaries on the end.
304 }
305
306 #ifdef ASSERT
307 // We must not copy any NULL placeholders left over from bootstrap.
308 for (int j = 0; j < s2->length(); j++) {
309 assert(s2->at(j) != NULL, "correct bootstrapping order");
310 }
311 #endif
312
313 this_kh->set_secondary_supers(s2);
314 }
315 }
316
317 GrowableArray<Klass*>* Klass::compute_secondary_supers(int num_extra_slots) {
318 assert(num_extra_slots == 0, "override for complex klasses");
319 set_secondary_supers(Universe::the_empty_klass_array());
320 return NULL;
321 }
322
323
324 InstanceKlass* Klass::superklass() const {
325 assert(super() == NULL || super()->is_instance_klass(), "must be instance klass");
326 return _super == NULL ? NULL : InstanceKlass::cast(_super);
327 }
328
329 void Klass::set_subklass(Klass* s) {
330 assert(s != this, "sanity check");
331 _subklass = s;
332 }
333
334 void Klass::set_next_sibling(Klass* s) {
335 assert(s != this, "sanity check");
336 _next_sibling = s;
337 }
338
339 void Klass::append_to_sibling_list() {
340 debug_only(verify();)
341 // add ourselves to superklass' subklass list
342 InstanceKlass* super = superklass();
343 if (super == NULL) return; // special case: class Object
344 assert((!super->is_interface() // interfaces cannot be supers
345 && (super->superklass() == NULL || !is_interface())),
346 "an interface can only be a subklass of Object");
347 Klass* prev_first_subklass = super->subklass();
348 if (prev_first_subklass != NULL) {
349 // set our sibling to be the superklass' previous first subklass
350 set_next_sibling(prev_first_subklass);
351 }
352 // make ourselves the superklass' first subklass
353 super->set_subklass(this);
354 debug_only(verify();)
355 }
356
357 bool Klass::is_loader_alive(BoolObjectClosure* is_alive) {
358 #ifdef ASSERT
359 // The class is alive iff the class loader is alive.
360 oop loader = class_loader();
361 bool loader_alive = (loader == NULL) || is_alive->do_object_b(loader);
362 #endif // ASSERT
363
364 // The class is alive if it's mirror is alive (which should be marked if the
365 // loader is alive) unless it's an anoymous class.
366 bool mirror_alive = is_alive->do_object_b(java_mirror());
367 assert(!mirror_alive || loader_alive, "loader must be alive if the mirror is"
368 " but not the other way around with anonymous classes");
369 return mirror_alive;
370 }
371
372 void Klass::clean_weak_klass_links(BoolObjectClosure* is_alive, bool clean_alive_klasses) {
373 if (!ClassUnloading) {
374 return;
375 }
376
377 Klass* root = SystemDictionary::Object_klass();
378 Stack<Klass*, mtGC> stack;
379
380 stack.push(root);
381 while (!stack.is_empty()) {
382 Klass* current = stack.pop();
383
384 assert(current->is_loader_alive(is_alive), "just checking, this should be live");
385
386 // Find and set the first alive subklass
387 Klass* sub = current->subklass();
388 while (sub != NULL && !sub->is_loader_alive(is_alive)) {
389 #ifndef PRODUCT
390 if (log_is_enabled(Trace, classunload)) {
391 ResourceMark rm;
392 log_trace(classunload)("[Unlinking class (subclass) %s]", sub->external_name());
393 }
394 #endif
395 sub = sub->next_sibling();
396 }
397 current->set_subklass(sub);
398 if (sub != NULL) {
399 stack.push(sub);
400 }
401
402 // Find and set the first alive sibling
403 Klass* sibling = current->next_sibling();
404 while (sibling != NULL && !sibling->is_loader_alive(is_alive)) {
405 if (log_is_enabled(Trace, classunload)) {
406 ResourceMark rm;
407 log_trace(classunload)("[Unlinking class (sibling) %s]", sibling->external_name());
408 }
409 sibling = sibling->next_sibling();
410 }
411 current->set_next_sibling(sibling);
412 if (sibling != NULL) {
413 stack.push(sibling);
414 }
415
416 // Clean the implementors list and method data.
417 if (clean_alive_klasses && current->is_instance_klass()) {
418 InstanceKlass* ik = InstanceKlass::cast(current);
419 ik->clean_weak_instanceklass_links(is_alive);
420 }
421 }
422 }
423
424 void Klass::klass_update_barrier_set(oop v) {
425 record_modified_oops();
426 }
427
428 // This barrier is used by G1 to remember the old oop values, so
429 // that we don't forget any objects that were live at the snapshot at
430 // the beginning. This function is only used when we write oops into Klasses.
431 void Klass::klass_update_barrier_set_pre(oop* p, oop v) {
432 #if INCLUDE_ALL_GCS
433 if (UseG1GC) {
434 oop obj = *p;
435 if (obj != NULL) {
436 G1SATBCardTableModRefBS::enqueue(obj);
437 }
438 }
439 #endif
440 }
441
442 void Klass::klass_oop_store(oop* p, oop v) {
443 assert(!Universe::heap()->is_in_reserved((void*)p), "Should store pointer into metadata");
444 assert(v == NULL || Universe::heap()->is_in_reserved((void*)v), "Should store pointer to an object");
445
446 // do the store
447 if (always_do_update_barrier) {
448 klass_oop_store((volatile oop*)p, v);
449 } else {
450 klass_update_barrier_set_pre(p, v);
451 *p = v;
452 klass_update_barrier_set(v);
453 }
454 }
455
456 void Klass::klass_oop_store(volatile oop* p, oop v) {
457 assert(!Universe::heap()->is_in_reserved((void*)p), "Should store pointer into metadata");
458 assert(v == NULL || Universe::heap()->is_in_reserved((void*)v), "Should store pointer to an object");
459
460 klass_update_barrier_set_pre((oop*)p, v); // Cast away volatile.
461 OrderAccess::release_store_ptr(p, v);
462 klass_update_barrier_set(v);
463 }
464
465 void Klass::oops_do(OopClosure* cl) {
466 cl->do_oop(&_java_mirror);
467 }
468
469 void Klass::remove_unshareable_info() {
470 assert (DumpSharedSpaces, "only called for DumpSharedSpaces");
471
472 set_subklass(NULL);
473 set_next_sibling(NULL);
474 // Clear the java mirror
475 set_java_mirror(NULL);
476 set_next_link(NULL);
477
478 // Null out class_loader_data because we don't share that yet.
479 set_class_loader_data(NULL);
480 }
481
482 void Klass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
483 TRACE_INIT_ID(this);
484 // If an exception happened during CDS restore, some of these fields may already be
485 // set. We leave the class on the CLD list, even if incomplete so that we don't
486 // modify the CLD list outside a safepoint.
487 if (class_loader_data() == NULL) {
488 // Restore class_loader_data to the null class loader data
489 set_class_loader_data(loader_data);
490
491 // Add to null class loader list first before creating the mirror
492 // (same order as class file parsing)
493 loader_data->add_class(this);
494 }
495
496 // Recreate the class mirror.
497 // Only recreate it if not present. A previous attempt to restore may have
498 // gotten an OOM later but keep the mirror if it was created.
499 if (java_mirror() == NULL) {
500 Handle loader = loader_data->class_loader();
501 java_lang_Class::create_mirror(this, loader, protection_domain, CHECK);
502 }
503 }
504
505 Klass* Klass::array_klass_or_null(int rank) {
506 EXCEPTION_MARK;
507 // No exception can be thrown by array_klass_impl when called with or_null == true.
508 // (In anycase, the execption mark will fail if it do so)
509 return array_klass_impl(true, rank, THREAD);
510 }
511
512
513 Klass* Klass::array_klass_or_null() {
514 EXCEPTION_MARK;
515 // No exception can be thrown by array_klass_impl when called with or_null == true.
516 // (In anycase, the execption mark will fail if it do so)
517 return array_klass_impl(true, THREAD);
518 }
519
520
521 Klass* Klass::array_klass_impl(bool or_null, int rank, TRAPS) {
522 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
523 return NULL;
524 }
525
526
527 Klass* Klass::array_klass_impl(bool or_null, TRAPS) {
528 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
529 return NULL;
530 }
531
532 oop Klass::class_loader() const { return class_loader_data()->class_loader(); }
533
534 // In product mode, this function doesn't have virtual function calls so
535 // there might be some performance advantage to handling InstanceKlass here.
536 const char* Klass::external_name() const {
537 if (is_instance_klass()) {
538 const InstanceKlass* ik = static_cast<const InstanceKlass*>(this);
539 if (ik->is_anonymous()) {
540 intptr_t hash = 0;
541 if (ik->java_mirror() != NULL) {
542 // java_mirror might not be created yet, return 0 as hash.
543 hash = ik->java_mirror()->identity_hash();
544 }
545 char hash_buf[40];
546 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
547 size_t hash_len = strlen(hash_buf);
548
549 size_t result_len = name()->utf8_length();
550 char* result = NEW_RESOURCE_ARRAY(char, result_len + hash_len + 1);
551 name()->as_klass_external_name(result, (int) result_len + 1);
552 assert(strlen(result) == result_len, "");
553 strcpy(result + result_len, hash_buf);
554 assert(strlen(result) == result_len + hash_len, "");
555 return result;
556 }
557 }
558 if (name() == NULL) return "<unknown>";
559 return name()->as_klass_external_name();
560 }
561
562
563 const char* Klass::signature_name() const {
564 if (name() == NULL) return "<unknown>";
565 return name()->as_C_string();
566 }
567
568 // Unless overridden, modifier_flags is 0.
569 jint Klass::compute_modifier_flags(TRAPS) const {
570 return 0;
571 }
572
573 int Klass::atomic_incr_biased_lock_revocation_count() {
574 return (int) Atomic::add(1, &_biased_lock_revocation_count);
575 }
576
577 // Unless overridden, jvmti_class_status has no flags set.
578 jint Klass::jvmti_class_status() const {
579 return 0;
580 }
581
582
583 // Printing
584
585 void Klass::print_on(outputStream* st) const {
586 ResourceMark rm;
587 // print title
588 st->print("%s", internal_name());
589 print_address_on(st);
590 st->cr();
591 }
592
593 void Klass::oop_print_on(oop obj, outputStream* st) {
594 ResourceMark rm;
595 // print title
596 st->print_cr("%s ", internal_name());
597 obj->print_address_on(st);
598
599 if (WizardMode) {
600 // print header
601 obj->mark()->print_on(st);
602 }
603
604 // print class
605 st->print(" - klass: ");
606 obj->klass()->print_value_on(st);
607 st->cr();
608 }
609
610 void Klass::oop_print_value_on(oop obj, outputStream* st) {
611 // print title
612 ResourceMark rm; // Cannot print in debug mode without this
613 st->print("%s", internal_name());
614 obj->print_address_on(st);
615 }
616
617 #if INCLUDE_SERVICES
618 // Size Statistics
619 void Klass::collect_statistics(KlassSizeStats *sz) const {
620 sz->_klass_bytes = sz->count(this);
621 sz->_mirror_bytes = sz->count(java_mirror());
622 sz->_secondary_supers_bytes = sz->count_array(secondary_supers());
623
624 sz->_ro_bytes += sz->_secondary_supers_bytes;
625 sz->_rw_bytes += sz->_klass_bytes + sz->_mirror_bytes;
626 }
627 #endif // INCLUDE_SERVICES
628
629 // Verification
630
631 void Klass::verify_on(outputStream* st) {
632
633 // This can be expensive, but it is worth checking that this klass is actually
634 // in the CLD graph but not in production.
635 assert(Metaspace::contains((address)this), "Should be");
636
637 guarantee(this->is_klass(),"should be klass");
638
639 if (super() != NULL) {
640 guarantee(super()->is_klass(), "should be klass");
641 }
642 if (secondary_super_cache() != NULL) {
643 Klass* ko = secondary_super_cache();
644 guarantee(ko->is_klass(), "should be klass");
645 }
646 for ( uint i = 0; i < primary_super_limit(); i++ ) {
647 Klass* ko = _primary_supers[i];
648 if (ko != NULL) {
649 guarantee(ko->is_klass(), "should be klass");
650 }
651 }
652
653 if (java_mirror() != NULL) {
654 guarantee(java_mirror()->is_oop(), "should be instance");
655 }
656 }
657
658 void Klass::oop_verify_on(oop obj, outputStream* st) {
659 guarantee(obj->is_oop(), "should be oop");
660 guarantee(obj->klass()->is_klass(), "klass field is not a klass");
661 }
662
663 #ifndef PRODUCT
664
665 bool Klass::verify_vtable_index(int i) {
666 int limit = vtable_length()/vtableEntry::size();
667 assert(i >= 0 && i < limit, "index %d out of bounds %d", i, limit);
668 return true;
669 }
670
671 bool Klass::verify_itable_index(int i) {
672 assert(is_instance_klass(), "");
673 int method_count = klassItable::method_count_for_interface(this);
674 assert(i >= 0 && i < method_count, "index out of bounds");
675 return true;
676 }
677
678 #endif
679
680 /////////////// Unit tests ///////////////
681
682 #ifndef PRODUCT
683
684 class TestKlass {
685 public:
686 static void test_oop_is_instanceClassLoader() {
687 Klass* klass = SystemDictionary::ClassLoader_klass();
688 guarantee(klass->is_instance_klass(), "assert");
689 guarantee(InstanceKlass::cast(klass)->is_class_loader_instance_klass(), "test failed");
690
691 klass = SystemDictionary::String_klass();
692 guarantee(!klass->is_instance_klass() ||
693 !InstanceKlass::cast(klass)->is_class_loader_instance_klass(),
694 "test failed");
695 }
696 };
697
698 void TestKlass_test() {
699 TestKlass::test_oop_is_instanceClassLoader();
700 }
701
702 #endif // PRODUCT