1 /* 2 * Copyright (c) 1997, 2015, 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 #if INCLUDE_ALL_GCS 44 #include "gc/g1/g1SATBCardTableModRefBS.hpp" 45 #endif // INCLUDE_ALL_GCS 46 47 void Klass::set_name(Symbol* n) { 48 _name = n; 49 if (_name != NULL) _name->increment_refcount(); 50 } 51 52 bool Klass::is_subclass_of(const Klass* k) const { 53 // Run up the super chain and check 54 if (this == k) return true; 55 56 Klass* t = const_cast<Klass*>(this)->super(); 57 58 while (t != NULL) { 59 if (t == k) return true; 60 t = t->super(); 61 } 62 return false; 63 } 64 65 bool Klass::search_secondary_supers(Klass* k) const { 66 // Put some extra logic here out-of-line, before the search proper. 67 // This cuts down the size of the inline method. 68 69 // This is necessary, since I am never in my own secondary_super list. 70 if (this == k) 71 return true; 72 // Scan the array-of-objects for a match 73 int cnt = secondary_supers()->length(); 74 for (int i = 0; i < cnt; i++) { 75 if (secondary_supers()->at(i) == k) { 76 ((Klass*)this)->set_secondary_super_cache(k); 77 return true; 78 } 79 } 80 return false; 81 } 82 83 // Return self, except for abstract classes with exactly 1 84 // implementor. Then return the 1 concrete implementation. 85 Klass *Klass::up_cast_abstract() { 86 Klass *r = this; 87 while( r->is_abstract() ) { // Receiver is abstract? 88 Klass *s = r->subklass(); // Check for exactly 1 subklass 89 if( !s || s->next_sibling() ) // Oops; wrong count; give up 90 return this; // Return 'this' as a no-progress flag 91 r = s; // Loop till find concrete class 92 } 93 return r; // Return the 1 concrete class 94 } 95 96 // Find LCA in class hierarchy 97 Klass *Klass::LCA( Klass *k2 ) { 98 Klass *k1 = this; 99 while( 1 ) { 100 if( k1->is_subtype_of(k2) ) return k2; 101 if( k2->is_subtype_of(k1) ) return k1; 102 k1 = k1->super(); 103 k2 = k2->super(); 104 } 105 } 106 107 108 void Klass::check_valid_for_instantiation(bool throwError, TRAPS) { 109 ResourceMark rm(THREAD); 110 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 111 : vmSymbols::java_lang_InstantiationException(), external_name()); 112 } 113 114 115 void Klass::copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS) { 116 THROW(vmSymbols::java_lang_ArrayStoreException()); 117 } 118 119 120 void Klass::initialize(TRAPS) { 121 ShouldNotReachHere(); 122 } 123 124 bool Klass::compute_is_subtype_of(Klass* k) { 125 assert(k->is_klass(), "argument must be a class"); 126 return is_subclass_of(k); 127 } 128 129 Klass* Klass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 130 #ifdef ASSERT 131 tty->print_cr("Error: find_field called on a klass oop." 132 " Likely error: reflection method does not correctly" 133 " wrap return value in a mirror object."); 134 #endif 135 ShouldNotReachHere(); 136 return NULL; 137 } 138 139 Method* Klass::uncached_lookup_method(const Symbol* name, const Symbol* signature, OverpassLookupMode overpass_mode) const { 140 #ifdef ASSERT 141 tty->print_cr("Error: uncached_lookup_method called on a klass oop." 142 " Likely error: reflection method does not correctly" 143 " wrap return value in a mirror object."); 144 #endif 145 ShouldNotReachHere(); 146 return NULL; 147 } 148 149 void* Klass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS) throw() { 150 return Metaspace::allocate(loader_data, word_size, /*read_only*/false, 151 MetaspaceObj::ClassType, THREAD); 152 } 153 154 // "Normal" instantiation is preceeded by a MetaspaceObj allocation 155 // which zeros out memory - calloc equivalent. 156 // The constructor is also used from init_self_patching_vtbl_list, 157 // which doesn't zero out the memory before calling the constructor. 158 // Need to set the _java_mirror field explicitly to not hit an assert that the field 159 // should be NULL before setting it. 160 Klass::Klass() : _prototype_header(markOopDesc::prototype()), 161 _shared_class_path_index(-1), 162 _java_mirror(NULL) { 163 164 _primary_supers[0] = this; 165 set_super_check_offset(in_bytes(primary_supers_offset())); 166 } 167 168 jint Klass::array_layout_helper(BasicType etype) { 169 assert(etype >= T_BOOLEAN && etype <= T_OBJECT, "valid etype"); 170 // Note that T_ARRAY is not allowed here. 171 int hsize = arrayOopDesc::base_offset_in_bytes(etype); 172 int esize = type2aelembytes(etype); 173 bool isobj = (etype == T_OBJECT); 174 int tag = isobj ? _lh_array_tag_obj_value : _lh_array_tag_type_value; 175 int lh = array_layout_helper(tag, hsize, etype, exact_log2(esize)); 176 177 assert(lh < (int)_lh_neutral_value, "must look like an array layout"); 178 assert(layout_helper_is_array(lh), "correct kind"); 179 assert(layout_helper_is_objArray(lh) == isobj, "correct kind"); 180 assert(layout_helper_is_typeArray(lh) == !isobj, "correct kind"); 181 assert(layout_helper_header_size(lh) == hsize, "correct decode"); 182 assert(layout_helper_element_type(lh) == etype, "correct decode"); 183 assert(1 << layout_helper_log2_element_size(lh) == esize, "correct decode"); 184 185 return lh; 186 } 187 188 bool Klass::can_be_primary_super_slow() const { 189 if (super() == NULL) 190 return true; 191 else if (super()->super_depth() >= primary_super_limit()-1) 192 return false; 193 else 194 return true; 195 } 196 197 void Klass::initialize_supers(Klass* k, TRAPS) { 198 if (FastSuperclassLimit == 0) { 199 // None of the other machinery matters. 200 set_super(k); 201 return; 202 } 203 if (k == NULL) { 204 set_super(NULL); 205 _primary_supers[0] = this; 206 assert(super_depth() == 0, "Object must already be initialized properly"); 207 } else if (k != super() || k == SystemDictionary::Object_klass()) { 208 assert(super() == NULL || super() == SystemDictionary::Object_klass(), 209 "initialize this only once to a non-trivial value"); 210 set_super(k); 211 Klass* sup = k; 212 int sup_depth = sup->super_depth(); 213 juint my_depth = MIN2(sup_depth + 1, (int)primary_super_limit()); 214 if (!can_be_primary_super_slow()) 215 my_depth = primary_super_limit(); 216 for (juint i = 0; i < my_depth; i++) { 217 _primary_supers[i] = sup->_primary_supers[i]; 218 } 219 Klass* *super_check_cell; 220 if (my_depth < primary_super_limit()) { 221 _primary_supers[my_depth] = this; 222 super_check_cell = &_primary_supers[my_depth]; 223 } else { 224 // Overflow of the primary_supers array forces me to be secondary. 225 super_check_cell = &_secondary_super_cache; 226 } 227 set_super_check_offset((address)super_check_cell - (address) this); 228 229 #ifdef ASSERT 230 { 231 juint j = super_depth(); 232 assert(j == my_depth, "computed accessor gets right answer"); 233 Klass* t = this; 234 while (!t->can_be_primary_super()) { 235 t = t->super(); 236 j = t->super_depth(); 237 } 238 for (juint j1 = j+1; j1 < primary_super_limit(); j1++) { 239 assert(primary_super_of_depth(j1) == NULL, "super list padding"); 240 } 241 while (t != NULL) { 242 assert(primary_super_of_depth(j) == t, "super list initialization"); 243 t = t->super(); 244 --j; 245 } 246 assert(j == (juint)-1, "correct depth count"); 247 } 248 #endif 249 } 250 251 if (secondary_supers() == NULL) { 252 KlassHandle this_kh (THREAD, this); 253 254 // Now compute the list of secondary supertypes. 255 // Secondaries can occasionally be on the super chain, 256 // if the inline "_primary_supers" array overflows. 257 int extras = 0; 258 Klass* p; 259 for (p = super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) { 260 ++extras; 261 } 262 263 ResourceMark rm(THREAD); // need to reclaim GrowableArrays allocated below 264 265 // Compute the "real" non-extra secondaries. 266 GrowableArray<Klass*>* secondaries = compute_secondary_supers(extras); 267 if (secondaries == NULL) { 268 // secondary_supers set by compute_secondary_supers 269 return; 270 } 271 272 GrowableArray<Klass*>* primaries = new GrowableArray<Klass*>(extras); 273 274 for (p = this_kh->super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) { 275 int i; // Scan for overflow primaries being duplicates of 2nd'arys 276 277 // This happens frequently for very deeply nested arrays: the 278 // primary superclass chain overflows into the secondary. The 279 // secondary list contains the element_klass's secondaries with 280 // an extra array dimension added. If the element_klass's 281 // secondary list already contains some primary overflows, they 282 // (with the extra level of array-ness) will collide with the 283 // normal primary superclass overflows. 284 for( i = 0; i < secondaries->length(); i++ ) { 285 if( secondaries->at(i) == p ) 286 break; 287 } 288 if( i < secondaries->length() ) 289 continue; // It's a dup, don't put it in 290 primaries->push(p); 291 } 292 // Combine the two arrays into a metadata object to pack the array. 293 // The primaries are added in the reverse order, then the secondaries. 294 int new_length = primaries->length() + secondaries->length(); 295 Array<Klass*>* s2 = MetadataFactory::new_array<Klass*>( 296 class_loader_data(), new_length, CHECK); 297 int fill_p = primaries->length(); 298 for (int j = 0; j < fill_p; j++) { 299 s2->at_put(j, primaries->pop()); // add primaries in reverse order. 300 } 301 for( int j = 0; j < secondaries->length(); j++ ) { 302 s2->at_put(j+fill_p, secondaries->at(j)); // add secondaries on the end. 303 } 304 305 #ifdef ASSERT 306 // We must not copy any NULL placeholders left over from bootstrap. 307 for (int j = 0; j < s2->length(); j++) { 308 assert(s2->at(j) != NULL, "correct bootstrapping order"); 309 } 310 #endif 311 312 this_kh->set_secondary_supers(s2); 313 } 314 } 315 316 GrowableArray<Klass*>* Klass::compute_secondary_supers(int num_extra_slots) { 317 assert(num_extra_slots == 0, "override for complex klasses"); 318 set_secondary_supers(Universe::the_empty_klass_array()); 319 return NULL; 320 } 321 322 323 InstanceKlass* Klass::superklass() const { 324 assert(super() == NULL || super()->is_instance_klass(), "must be instance klass"); 325 return _super == NULL ? NULL : InstanceKlass::cast(_super); 326 } 327 328 void Klass::set_subklass(Klass* s) { 329 assert(s != this, "sanity check"); 330 _subklass = s; 331 } 332 333 void Klass::set_next_sibling(Klass* s) { 334 assert(s != this, "sanity check"); 335 _next_sibling = s; 336 } 337 338 void Klass::append_to_sibling_list() { 339 debug_only(verify();) 340 // add ourselves to superklass' subklass list 341 InstanceKlass* super = superklass(); 342 if (super == NULL) return; // special case: class Object 343 assert((!super->is_interface() // interfaces cannot be supers 344 && (super->superklass() == NULL || !is_interface())), 345 "an interface can only be a subklass of Object"); 346 Klass* prev_first_subklass = super->subklass(); 347 if (prev_first_subklass != NULL) { 348 // set our sibling to be the superklass' previous first subklass 349 set_next_sibling(prev_first_subklass); 350 } 351 // make ourselves the superklass' first subklass 352 super->set_subklass(this); 353 debug_only(verify();) 354 } 355 356 bool Klass::is_loader_alive(BoolObjectClosure* is_alive) { 357 #ifdef ASSERT 358 // The class is alive iff the class loader is alive. 359 oop loader = class_loader(); 360 bool loader_alive = (loader == NULL) || is_alive->do_object_b(loader); 361 #endif // ASSERT 362 363 // The class is alive if it's mirror is alive (which should be marked if the 364 // loader is alive) unless it's an anoymous class. 365 bool mirror_alive = is_alive->do_object_b(java_mirror()); 366 assert(!mirror_alive || loader_alive, "loader must be alive if the mirror is" 367 " but not the other way around with anonymous classes"); 368 return mirror_alive; 369 } 370 371 void Klass::clean_weak_klass_links(BoolObjectClosure* is_alive, bool clean_alive_klasses) { 372 if (!ClassUnloading) { 373 return; 374 } 375 376 Klass* root = SystemDictionary::Object_klass(); 377 Stack<Klass*, mtGC> stack; 378 379 stack.push(root); 380 while (!stack.is_empty()) { 381 Klass* current = stack.pop(); 382 383 assert(current->is_loader_alive(is_alive), "just checking, this should be live"); 384 385 // Find and set the first alive subklass 386 Klass* sub = current->subklass(); 387 while (sub != NULL && !sub->is_loader_alive(is_alive)) { 388 #ifndef PRODUCT 389 if (TraceClassUnloading && WizardMode) { 390 ResourceMark rm; 391 tty->print_cr("[Unlinking class (subclass) %s]", sub->external_name()); 392 } 393 #endif 394 sub = sub->next_sibling(); 395 } 396 current->set_subklass(sub); 397 if (sub != NULL) { 398 stack.push(sub); 399 } 400 401 // Find and set the first alive sibling 402 Klass* sibling = current->next_sibling(); 403 while (sibling != NULL && !sibling->is_loader_alive(is_alive)) { 404 if (TraceClassUnloading && WizardMode) { 405 ResourceMark rm; 406 tty->print_cr("[Unlinking class (sibling) %s]", sibling->external_name()); 407 } 408 sibling = sibling->next_sibling(); 409 } 410 current->set_next_sibling(sibling); 411 if (sibling != NULL) { 412 stack.push(sibling); 413 } 414 415 // Clean the implementors list and method data. 416 if (clean_alive_klasses && current->is_instance_klass()) { 417 InstanceKlass* ik = InstanceKlass::cast(current); 418 ik->clean_weak_instanceklass_links(is_alive); 419 } 420 } 421 } 422 423 void Klass::klass_update_barrier_set(oop v) { 424 record_modified_oops(); 425 } 426 427 // This barrier is used by G1 to remember the old oop values, so 428 // that we don't forget any objects that were live at the snapshot at 429 // the beginning. This function is only used when we write oops into Klasses. 430 void Klass::klass_update_barrier_set_pre(oop* p, oop v) { 431 #if INCLUDE_ALL_GCS 432 if (UseG1GC) { 433 oop obj = *p; 434 if (obj != NULL) { 435 G1SATBCardTableModRefBS::enqueue(obj); 436 } 437 } 438 #endif 439 } 440 441 void Klass::klass_oop_store(oop* p, oop v) { 442 assert(!Universe::heap()->is_in_reserved((void*)p), "Should store pointer into metadata"); 443 assert(v == NULL || Universe::heap()->is_in_reserved((void*)v), "Should store pointer to an object"); 444 445 // do the store 446 if (always_do_update_barrier) { 447 klass_oop_store((volatile oop*)p, v); 448 } else { 449 klass_update_barrier_set_pre(p, v); 450 *p = v; 451 klass_update_barrier_set(v); 452 } 453 } 454 455 void Klass::klass_oop_store(volatile oop* p, oop v) { 456 assert(!Universe::heap()->is_in_reserved((void*)p), "Should store pointer into metadata"); 457 assert(v == NULL || Universe::heap()->is_in_reserved((void*)v), "Should store pointer to an object"); 458 459 klass_update_barrier_set_pre((oop*)p, v); // Cast away volatile. 460 OrderAccess::release_store_ptr(p, v); 461 klass_update_barrier_set(v); 462 } 463 464 void Klass::oops_do(OopClosure* cl) { 465 cl->do_oop(&_java_mirror); 466 } 467 468 void Klass::remove_unshareable_info() { 469 assert (DumpSharedSpaces, "only called for DumpSharedSpaces"); 470 471 set_subklass(NULL); 472 set_next_sibling(NULL); 473 // Clear the java mirror 474 set_java_mirror(NULL); 475 set_next_link(NULL); 476 477 // Null out class_loader_data because we don't share that yet. 478 set_class_loader_data(NULL); 479 } 480 481 void Klass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) { 482 TRACE_INIT_ID(this); 483 // If an exception happened during CDS restore, some of these fields may already be 484 // set. We leave the class on the CLD list, even if incomplete so that we don't 485 // modify the CLD list outside a safepoint. 486 if (class_loader_data() == NULL) { 487 // Restore class_loader_data to the null class loader data 488 set_class_loader_data(loader_data); 489 490 // Add to null class loader list first before creating the mirror 491 // (same order as class file parsing) 492 loader_data->add_class(this); 493 } 494 495 // Recreate the class mirror. 496 // Only recreate it if not present. A previous attempt to restore may have 497 // gotten an OOM later but keep the mirror if it was created. 498 if (java_mirror() == NULL) { 499 Handle loader = loader_data->class_loader(); 500 java_lang_Class::create_mirror(this, loader, protection_domain, CHECK); 501 } 502 } 503 504 Klass* Klass::array_klass_or_null(int rank) { 505 EXCEPTION_MARK; 506 // No exception can be thrown by array_klass_impl when called with or_null == true. 507 // (In anycase, the execption mark will fail if it do so) 508 return array_klass_impl(true, rank, THREAD); 509 } 510 511 512 Klass* Klass::array_klass_or_null() { 513 EXCEPTION_MARK; 514 // No exception can be thrown by array_klass_impl when called with or_null == true. 515 // (In anycase, the execption mark will fail if it do so) 516 return array_klass_impl(true, THREAD); 517 } 518 519 520 Klass* Klass::array_klass_impl(bool or_null, int rank, TRAPS) { 521 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass"); 522 return NULL; 523 } 524 525 526 Klass* Klass::array_klass_impl(bool or_null, TRAPS) { 527 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass"); 528 return NULL; 529 } 530 531 oop Klass::class_loader() const { return class_loader_data()->class_loader(); } 532 533 // In product mode, this function doesn't have virtual function calls so 534 // there might be some performance advantage to handling InstanceKlass here. 535 const char* Klass::external_name() const { 536 if (is_instance_klass()) { 537 const InstanceKlass* ik = static_cast<const InstanceKlass*>(this); 538 if (ik->is_anonymous()) { 539 intptr_t hash = 0; 540 if (ik->java_mirror() != NULL) { 541 // java_mirror might not be created yet, return 0 as hash. 542 hash = ik->java_mirror()->identity_hash(); 543 } 544 char hash_buf[40]; 545 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash); 546 size_t hash_len = strlen(hash_buf); 547 548 size_t result_len = name()->utf8_length(); 549 char* result = NEW_RESOURCE_ARRAY(char, result_len + hash_len + 1); 550 name()->as_klass_external_name(result, (int) result_len + 1); 551 assert(strlen(result) == result_len, ""); 552 strcpy(result + result_len, hash_buf); 553 assert(strlen(result) == result_len + hash_len, ""); 554 return result; 555 } 556 } 557 if (name() == NULL) return "<unknown>"; 558 return name()->as_klass_external_name(); 559 } 560 561 562 const char* Klass::signature_name() const { 563 if (name() == NULL) return "<unknown>"; 564 return name()->as_C_string(); 565 } 566 567 // Unless overridden, modifier_flags is 0. 568 jint Klass::compute_modifier_flags(TRAPS) const { 569 return 0; 570 } 571 572 int Klass::atomic_incr_biased_lock_revocation_count() { 573 return (int) Atomic::add(1, &_biased_lock_revocation_count); 574 } 575 576 // Unless overridden, jvmti_class_status has no flags set. 577 jint Klass::jvmti_class_status() const { 578 return 0; 579 } 580 581 582 // Printing 583 584 void Klass::print_on(outputStream* st) const { 585 ResourceMark rm; 586 // print title 587 st->print("%s", internal_name()); 588 print_address_on(st); 589 st->cr(); 590 } 591 592 void Klass::oop_print_on(oop obj, outputStream* st) { 593 ResourceMark rm; 594 // print title 595 st->print_cr("%s ", internal_name()); 596 obj->print_address_on(st); 597 598 if (WizardMode) { 599 // print header 600 obj->mark()->print_on(st); 601 } 602 603 // print class 604 st->print(" - klass: "); 605 obj->klass()->print_value_on(st); 606 st->cr(); 607 } 608 609 void Klass::oop_print_value_on(oop obj, outputStream* st) { 610 // print title 611 ResourceMark rm; // Cannot print in debug mode without this 612 st->print("%s", internal_name()); 613 obj->print_address_on(st); 614 } 615 616 #if INCLUDE_SERVICES 617 // Size Statistics 618 void Klass::collect_statistics(KlassSizeStats *sz) const { 619 sz->_klass_bytes = sz->count(this); 620 sz->_mirror_bytes = sz->count(java_mirror()); 621 sz->_secondary_supers_bytes = sz->count_array(secondary_supers()); 622 623 sz->_ro_bytes += sz->_secondary_supers_bytes; 624 sz->_rw_bytes += sz->_klass_bytes + sz->_mirror_bytes; 625 } 626 #endif // INCLUDE_SERVICES 627 628 // Verification 629 630 void Klass::verify_on(outputStream* st) { 631 632 // This can be expensive, but it is worth checking that this klass is actually 633 // in the CLD graph but not in production. 634 assert(Metaspace::contains((address)this), "Should be"); 635 636 guarantee(this->is_klass(),"should be klass"); 637 638 if (super() != NULL) { 639 guarantee(super()->is_klass(), "should be klass"); 640 } 641 if (secondary_super_cache() != NULL) { 642 Klass* ko = secondary_super_cache(); 643 guarantee(ko->is_klass(), "should be klass"); 644 } 645 for ( uint i = 0; i < primary_super_limit(); i++ ) { 646 Klass* ko = _primary_supers[i]; 647 if (ko != NULL) { 648 guarantee(ko->is_klass(), "should be klass"); 649 } 650 } 651 652 if (java_mirror() != NULL) { 653 guarantee(java_mirror()->is_oop(), "should be instance"); 654 } 655 } 656 657 void Klass::oop_verify_on(oop obj, outputStream* st) { 658 guarantee(obj->is_oop(), "should be oop"); 659 guarantee(obj->klass()->is_klass(), "klass field is not a klass"); 660 } 661 662 #ifndef PRODUCT 663 664 bool Klass::verify_vtable_index(int i) { 665 int limit = vtable_length()/vtableEntry::size(); 666 assert(i >= 0 && i < limit, "index %d out of bounds %d", i, limit); 667 return true; 668 } 669 670 bool Klass::verify_itable_index(int i) { 671 assert(is_instance_klass(), ""); 672 int method_count = klassItable::method_count_for_interface(this); 673 assert(i >= 0 && i < method_count, "index out of bounds"); 674 return true; 675 } 676 677 #endif 678 679 /////////////// Unit tests /////////////// 680 681 #ifndef PRODUCT 682 683 class TestKlass { 684 public: 685 static void test_oop_is_instanceClassLoader() { 686 Klass* klass = SystemDictionary::ClassLoader_klass(); 687 guarantee(klass->is_instance_klass(), "assert"); 688 guarantee(InstanceKlass::cast(klass)->is_class_loader_instance_klass(), "test failed"); 689 690 klass = SystemDictionary::String_klass(); 691 guarantee(!klass->is_instance_klass() || 692 !InstanceKlass::cast(klass)->is_class_loader_instance_klass(), 693 "test failed"); 694 } 695 }; 696 697 void TestKlass_test() { 698 TestKlass::test_oop_is_instanceClassLoader(); 699 } 700 701 #endif // PRODUCT