1 /* 2 * Copyright (c) 1997, 2018, 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_VM_CLASSFILE_SYSTEMDICTIONARY_HPP 26 #define SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP 27 28 #include "classfile/classLoader.hpp" 29 #include "jvmci/systemDictionary_jvmci.hpp" 30 #include "oops/objArrayOop.hpp" 31 #include "oops/symbol.hpp" 32 #include "runtime/java.hpp" 33 #include "runtime/reflectionUtils.hpp" 34 #include "runtime/signature.hpp" 35 #include "utilities/hashtable.hpp" 36 37 // The dictionary in each ClassLoaderData stores all loaded classes, either 38 // initiatied by its class loader or defined by its class loader: 39 // 40 // class loader -> ClassLoaderData -> [class, protection domain set] 41 // 42 // Classes are loaded lazily. The default VM class loader is 43 // represented as NULL. 44 45 // The underlying data structure is an open hash table (Dictionary) per 46 // ClassLoaderData with a fixed number of buckets. During loading the 47 // class loader object is locked, (for the VM loader a private lock object is used). 48 // The global SystemDictionary_lock is held for all additions into the ClassLoaderData 49 // dictionaries. TODO: fix lock granularity so that class loading can 50 // be done concurrently, but only by different loaders. 51 // 52 // During loading a placeholder (name, loader) is temporarily placed in 53 // a side data structure, and is used to detect ClassCircularityErrors 54 // and to perform verification during GC. A GC can occur in the midst 55 // of class loading, as we call out to Java, have to take locks, etc. 56 // 57 // When class loading is finished, a new entry is added to the dictionary 58 // of the class loader and the placeholder is removed. Note that the protection 59 // domain field of the dictionary entry has not yet been filled in when 60 // the "real" dictionary entry is created. 61 // 62 // Clients of this class who are interested in finding if a class has 63 // been completely loaded -- not classes in the process of being loaded -- 64 // can read the dictionary unlocked. This is safe because 65 // - entries are only deleted at safepoints 66 // - readers cannot come to a safepoint while actively examining 67 // an entry (an entry cannot be deleted from under a reader) 68 // - entries must be fully formed before they are available to concurrent 69 // readers (we must ensure write ordering) 70 // 71 // Note that placeholders are deleted at any time, as they are removed 72 // when a class is completely loaded. Therefore, readers as well as writers 73 // of placeholders must hold the SystemDictionary_lock. 74 // 75 76 class ClassFileStream; 77 class Dictionary; 78 class PlaceholderTable; 79 class LoaderConstraintTable; 80 template <MEMFLAGS F> class HashtableBucket; 81 class ResolutionErrorTable; 82 class SymbolPropertyTable; 83 class ProtectionDomainCacheTable; 84 class ProtectionDomainCacheEntry; 85 class GCTimer; 86 class OopStorage; 87 88 #define WK_KLASS_ENUM_NAME(kname) kname##_knum 89 90 // Certain classes, such as java.lang.Object and java.lang.String, 91 // are "well-known", in the sense that no class loader is allowed 92 // to provide a different definition. 93 // 94 // Each well-known class has a short klass name (like object_klass), 95 // and a vmSymbol name (like java_lang_Object). 96 // 97 // The order of these definitions is significant: the classes are 98 // resolved during early VM start-up by resolve_well_known_classes 99 // in this order. Changing the order may require careful restructuring 100 // of the VM start-up sequence. 101 // 102 #define WK_KLASSES_DO(do_klass) \ 103 /* well-known classes */ \ 104 do_klass(Object_klass, java_lang_Object ) \ 105 do_klass(String_klass, java_lang_String ) \ 106 do_klass(Class_klass, java_lang_Class ) \ 107 do_klass(Cloneable_klass, java_lang_Cloneable ) \ 108 do_klass(ClassLoader_klass, java_lang_ClassLoader ) \ 109 do_klass(Serializable_klass, java_io_Serializable ) \ 110 do_klass(System_klass, java_lang_System ) \ 111 do_klass(Throwable_klass, java_lang_Throwable ) \ 112 do_klass(Error_klass, java_lang_Error ) \ 113 do_klass(ThreadDeath_klass, java_lang_ThreadDeath ) \ 114 do_klass(Exception_klass, java_lang_Exception ) \ 115 do_klass(RuntimeException_klass, java_lang_RuntimeException ) \ 116 do_klass(SecurityManager_klass, java_lang_SecurityManager ) \ 117 do_klass(ProtectionDomain_klass, java_security_ProtectionDomain ) \ 118 do_klass(AccessControlContext_klass, java_security_AccessControlContext ) \ 119 do_klass(SecureClassLoader_klass, java_security_SecureClassLoader ) \ 120 do_klass(ClassNotFoundException_klass, java_lang_ClassNotFoundException ) \ 121 do_klass(NoClassDefFoundError_klass, java_lang_NoClassDefFoundError ) \ 122 do_klass(LinkageError_klass, java_lang_LinkageError ) \ 123 do_klass(ClassCastException_klass, java_lang_ClassCastException ) \ 124 do_klass(ArrayStoreException_klass, java_lang_ArrayStoreException ) \ 125 do_klass(VirtualMachineError_klass, java_lang_VirtualMachineError ) \ 126 do_klass(OutOfMemoryError_klass, java_lang_OutOfMemoryError ) \ 127 do_klass(StackOverflowError_klass, java_lang_StackOverflowError ) \ 128 do_klass(IllegalMonitorStateException_klass, java_lang_IllegalMonitorStateException ) \ 129 do_klass(Reference_klass, java_lang_ref_Reference ) \ 130 \ 131 /* ref klasses and set reference types */ \ 132 do_klass(SoftReference_klass, java_lang_ref_SoftReference ) \ 133 do_klass(WeakReference_klass, java_lang_ref_WeakReference ) \ 134 do_klass(FinalReference_klass, java_lang_ref_FinalReference ) \ 135 do_klass(PhantomReference_klass, java_lang_ref_PhantomReference ) \ 136 do_klass(Finalizer_klass, java_lang_ref_Finalizer ) \ 137 \ 138 do_klass(Thread_klass, java_lang_Thread ) \ 139 do_klass(ThreadGroup_klass, java_lang_ThreadGroup ) \ 140 do_klass(Properties_klass, java_util_Properties ) \ 141 do_klass(Module_klass, java_lang_Module ) \ 142 do_klass(reflect_AccessibleObject_klass, java_lang_reflect_AccessibleObject ) \ 143 do_klass(reflect_Field_klass, java_lang_reflect_Field ) \ 144 do_klass(reflect_Parameter_klass, java_lang_reflect_Parameter ) \ 145 do_klass(reflect_Method_klass, java_lang_reflect_Method ) \ 146 do_klass(reflect_Constructor_klass, java_lang_reflect_Constructor ) \ 147 \ 148 /* NOTE: needed too early in bootstrapping process to have checks based on JDK version */ \ 149 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \ 150 do_klass(reflect_MagicAccessorImpl_klass, reflect_MagicAccessorImpl ) \ 151 do_klass(reflect_MethodAccessorImpl_klass, reflect_MethodAccessorImpl ) \ 152 do_klass(reflect_ConstructorAccessorImpl_klass, reflect_ConstructorAccessorImpl ) \ 153 do_klass(reflect_DelegatingClassLoader_klass, reflect_DelegatingClassLoader ) \ 154 do_klass(reflect_ConstantPool_klass, reflect_ConstantPool ) \ 155 do_klass(reflect_UnsafeStaticFieldAccessorImpl_klass, reflect_UnsafeStaticFieldAccessorImpl ) \ 156 do_klass(reflect_CallerSensitive_klass, reflect_CallerSensitive ) \ 157 \ 158 /* support for dynamic typing; it's OK if these are NULL in earlier JDKs */ \ 159 do_klass(DirectMethodHandle_klass, java_lang_invoke_DirectMethodHandle ) \ 160 do_klass(MethodHandle_klass, java_lang_invoke_MethodHandle ) \ 161 do_klass(VarHandle_klass, java_lang_invoke_VarHandle ) \ 162 do_klass(MemberName_klass, java_lang_invoke_MemberName ) \ 163 do_klass(ResolvedMethodName_klass, java_lang_invoke_ResolvedMethodName ) \ 164 do_klass(MethodHandleNatives_klass, java_lang_invoke_MethodHandleNatives ) \ 165 do_klass(LambdaForm_klass, java_lang_invoke_LambdaForm ) \ 166 do_klass(MethodType_klass, java_lang_invoke_MethodType ) \ 167 do_klass(BootstrapMethodError_klass, java_lang_BootstrapMethodError ) \ 168 do_klass(CallSite_klass, java_lang_invoke_CallSite ) \ 169 do_klass(Context_klass, java_lang_invoke_MethodHandleNatives_CallSiteContext ) \ 170 do_klass(ConstantCallSite_klass, java_lang_invoke_ConstantCallSite ) \ 171 do_klass(MutableCallSite_klass, java_lang_invoke_MutableCallSite ) \ 172 do_klass(VolatileCallSite_klass, java_lang_invoke_VolatileCallSite ) \ 173 /* Note: MethodHandle must be first, and VolatileCallSite last in group */ \ 174 \ 175 do_klass(AssertionStatusDirectives_klass, java_lang_AssertionStatusDirectives ) \ 176 do_klass(StringBuffer_klass, java_lang_StringBuffer ) \ 177 do_klass(StringBuilder_klass, java_lang_StringBuilder ) \ 178 do_klass(internal_Unsafe_klass, jdk_internal_misc_Unsafe ) \ 179 do_klass(module_Modules_klass, jdk_internal_module_Modules ) \ 180 \ 181 /* support for CDS */ \ 182 do_klass(ByteArrayInputStream_klass, java_io_ByteArrayInputStream ) \ 183 do_klass(URL_klass, java_net_URL ) \ 184 do_klass(Jar_Manifest_klass, java_util_jar_Manifest ) \ 185 do_klass(jdk_internal_loader_ClassLoaders_klass, jdk_internal_loader_ClassLoaders ) \ 186 do_klass(jdk_internal_loader_ClassLoaders_AppClassLoader_klass, jdk_internal_loader_ClassLoaders_AppClassLoader) \ 187 do_klass(jdk_internal_loader_ClassLoaders_PlatformClassLoader_klass, jdk_internal_loader_ClassLoaders_PlatformClassLoader) \ 188 do_klass(CodeSource_klass, java_security_CodeSource ) \ 189 \ 190 do_klass(StackTraceElement_klass, java_lang_StackTraceElement ) \ 191 \ 192 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \ 193 do_klass(nio_Buffer_klass, java_nio_Buffer ) \ 194 \ 195 /* Stack Walking */ \ 196 do_klass(StackWalker_klass, java_lang_StackWalker ) \ 197 do_klass(AbstractStackWalker_klass, java_lang_StackStreamFactory_AbstractStackWalker ) \ 198 do_klass(StackFrameInfo_klass, java_lang_StackFrameInfo ) \ 199 do_klass(LiveStackFrameInfo_klass, java_lang_LiveStackFrameInfo ) \ 200 \ 201 /* support for stack dump lock analysis */ \ 202 do_klass(java_util_concurrent_locks_AbstractOwnableSynchronizer_klass, java_util_concurrent_locks_AbstractOwnableSynchronizer) \ 203 \ 204 /* boxing klasses */ \ 205 do_klass(Boolean_klass, java_lang_Boolean ) \ 206 do_klass(Character_klass, java_lang_Character ) \ 207 do_klass(Float_klass, java_lang_Float ) \ 208 do_klass(Double_klass, java_lang_Double ) \ 209 do_klass(Byte_klass, java_lang_Byte ) \ 210 do_klass(Short_klass, java_lang_Short ) \ 211 do_klass(Integer_klass, java_lang_Integer ) \ 212 do_klass(Long_klass, java_lang_Long ) \ 213 \ 214 /* JVMCI classes. These are loaded on-demand. */ \ 215 JVMCI_WK_KLASSES_DO(do_klass) \ 216 \ 217 /*end*/ 218 219 220 class SystemDictionary : AllStatic { 221 friend class VMStructs; 222 friend class SystemDictionaryHandles; 223 224 public: 225 enum WKID { 226 NO_WKID = 0, 227 228 #define WK_KLASS_ENUM(name, symbol) WK_KLASS_ENUM_NAME(name), WK_KLASS_ENUM_NAME(symbol) = WK_KLASS_ENUM_NAME(name), 229 WK_KLASSES_DO(WK_KLASS_ENUM) 230 #undef WK_KLASS_ENUM 231 232 WKID_LIMIT, 233 234 #if INCLUDE_JVMCI 235 FIRST_JVMCI_WKID = WK_KLASS_ENUM_NAME(JVMCI_klass), 236 LAST_JVMCI_WKID = WK_KLASS_ENUM_NAME(Value_klass), 237 #endif 238 239 FIRST_WKID = NO_WKID + 1 240 }; 241 242 // Returns a class with a given class name and class loader. Loads the 243 // class if needed. If not found a NoClassDefFoundError or a 244 // ClassNotFoundException is thrown, depending on the value on the 245 // throw_error flag. For most uses the throw_error argument should be set 246 // to true. 247 248 static Klass* resolve_or_fail(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS); 249 // Convenient call for null loader and protection domain. 250 static Klass* resolve_or_fail(Symbol* class_name, bool throw_error, TRAPS); 251 protected: 252 // handle error translation for resolve_or_null results 253 static Klass* handle_resolution_exception(Symbol* class_name, bool throw_error, Klass* klass, TRAPS); 254 255 public: 256 257 // Returns a class with a given class name and class loader. 258 // Loads the class if needed. If not found NULL is returned. 259 static Klass* resolve_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS); 260 // Version with null loader and protection domain 261 static Klass* resolve_or_null(Symbol* class_name, TRAPS); 262 263 // Resolve a superclass or superinterface. Called from ClassFileParser, 264 // parse_interfaces, resolve_instance_class_or_null, load_shared_class 265 // "child_name" is the class whose super class or interface is being resolved. 266 static InstanceKlass* resolve_super_or_fail(Symbol* child_name, 267 Symbol* class_name, 268 Handle class_loader, 269 Handle protection_domain, 270 bool is_superclass, 271 TRAPS); 272 273 // Parse new stream. This won't update the dictionary or 274 // class hierarchy, simply parse the stream. Used by JVMTI RedefineClasses. 275 // Also used by Unsafe_DefineAnonymousClass 276 static InstanceKlass* parse_stream(Symbol* class_name, 277 Handle class_loader, 278 Handle protection_domain, 279 ClassFileStream* st, 280 TRAPS) { 281 return parse_stream(class_name, 282 class_loader, 283 protection_domain, 284 st, 285 NULL, // unsafe_anonymous_host 286 NULL, // cp_patches 287 THREAD); 288 } 289 static InstanceKlass* parse_stream(Symbol* class_name, 290 Handle class_loader, 291 Handle protection_domain, 292 ClassFileStream* st, 293 const InstanceKlass* unsafe_anonymous_host, 294 GrowableArray<Handle>* cp_patches, 295 TRAPS); 296 297 // Resolve from stream (called by jni_DefineClass and JVM_DefineClass) 298 static InstanceKlass* resolve_from_stream(Symbol* class_name, 299 Handle class_loader, 300 Handle protection_domain, 301 ClassFileStream* st, 302 TRAPS); 303 304 // Lookup an already loaded class. If not found NULL is returned. 305 static Klass* find(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS); 306 307 // Lookup an already loaded instance or array class. 308 // Do not make any queries to class loaders; consult only the cache. 309 // If not found NULL is returned. 310 static Klass* find_instance_or_array_klass(Symbol* class_name, 311 Handle class_loader, 312 Handle protection_domain, 313 TRAPS); 314 315 // Lookup an instance or array class that has already been loaded 316 // either into the given class loader, or else into another class 317 // loader that is constrained (via loader constraints) to produce 318 // a consistent class. Do not take protection domains into account. 319 // Do not make any queries to class loaders; consult only the cache. 320 // Return NULL if the class is not found. 321 // 322 // This function is a strict superset of find_instance_or_array_klass. 323 // This function (the unchecked version) makes a conservative prediction 324 // of the result of the checked version, assuming successful lookup. 325 // If both functions return non-null, they must return the same value. 326 // Also, the unchecked version may sometimes be non-null where the 327 // checked version is null. This can occur in several ways: 328 // 1. No query has yet been made to the class loader. 329 // 2. The class loader was queried, but chose not to delegate. 330 // 3. ClassLoader.checkPackageAccess rejected a proposed protection domain. 331 // 4. Loading was attempted, but there was a linkage error of some sort. 332 // In all of these cases, the loader constraints on this type are 333 // satisfied, and it is safe for classes in the given class loader 334 // to manipulate strongly-typed values of the found class, subject 335 // to local linkage and access checks. 336 static Klass* find_constrained_instance_or_array_klass(Symbol* class_name, 337 Handle class_loader, 338 TRAPS); 339 340 static void classes_do(MetaspaceClosure* it); 341 // Iterate over all methods in all klasses 342 343 static void methods_do(void f(Method*)); 344 345 // Garbage collection support 346 347 // Unload (that is, break root links to) all unmarked classes and 348 // loaders. Returns "true" iff something was unloaded. 349 static bool do_unloading(GCTimer* gc_timer); 350 351 // Used by DumpSharedSpaces only to remove classes that failed verification 352 static void remove_classes_in_error_state(); 353 354 static int calculate_systemdictionary_size(int loadedclasses); 355 356 // Applies "f->do_oop" to all root oops in the system dictionary. 357 static void oops_do(OopClosure* f); 358 359 // System loader lock 360 static oop system_loader_lock() { return _system_loader_lock_obj; } 361 362 // Protection Domain Table 363 static ProtectionDomainCacheTable* pd_cache_table() { return _pd_cache_table; } 364 365 public: 366 // Sharing support. 367 static void reorder_dictionary_for_sharing() NOT_CDS_RETURN; 368 static void combine_shared_dictionaries(); 369 static size_t count_bytes_for_buckets(); 370 static size_t count_bytes_for_table(); 371 static void copy_buckets(char* top, char* end); 372 static void copy_table(char* top, char* end); 373 static void set_shared_dictionary(HashtableBucket<mtClass>* t, int length, 374 int number_of_entries); 375 // Printing 376 static void print() { return print_on(tty); } 377 static void print_on(outputStream* st); 378 static void print_shared(outputStream* st); 379 static void dump(outputStream* st, bool verbose); 380 381 // Monotonically increasing counter which grows as classes are 382 // loaded or modifications such as hot-swapping or setting/removing 383 // of breakpoints are performed 384 static inline int number_of_modifications() { assert_locked_or_safepoint(Compile_lock); return _number_of_modifications; } 385 // Needed by evolution and breakpoint code 386 static inline void notice_modification() { assert_locked_or_safepoint(Compile_lock); ++_number_of_modifications; } 387 388 // Verification 389 static void verify(); 390 391 // Initialization 392 static void initialize(TRAPS); 393 394 // Checked fast access to the well-known classes -- so that you don't try to use them 395 // before they are resolved. 396 static InstanceKlass* check_klass(InstanceKlass* k) { 397 assert(k != NULL, "klass not loaded"); 398 return k; 399 } 400 401 static bool resolve_wk_klass(WKID id, TRAPS); 402 static void resolve_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS); 403 static void resolve_wk_klasses_through(WKID end_id, WKID &start_id, TRAPS) { 404 int limit = (int)end_id + 1; 405 resolve_wk_klasses_until((WKID) limit, start_id, THREAD); 406 } 407 408 public: 409 #define WK_KLASS_DECLARE(name, symbol) \ 410 static InstanceKlass* name() { return check_klass(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); } \ 411 static InstanceKlass** name##_addr() { \ 412 return &_well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]; \ 413 } \ 414 static bool name##_is_loaded() { \ 415 return _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)] != NULL; \ 416 } 417 WK_KLASSES_DO(WK_KLASS_DECLARE); 418 #undef WK_KLASS_DECLARE 419 420 static InstanceKlass* well_known_klass(WKID id) { 421 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob"); 422 return _well_known_klasses[id]; 423 } 424 425 static InstanceKlass** well_known_klass_addr(WKID id) { 426 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob"); 427 return &_well_known_klasses[id]; 428 } 429 static void well_known_klasses_do(MetaspaceClosure* it); 430 431 // Local definition for direct access to the private array: 432 #define WK_KLASS(name) _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)] 433 434 static InstanceKlass* box_klass(BasicType t) { 435 assert((uint)t < T_VOID+1, "range check"); 436 return check_klass(_box_klasses[t]); 437 } 438 static BasicType box_klass_type(Klass* k); // inverse of box_klass 439 #ifdef ASSERT 440 static bool is_well_known_klass(Klass* k) { 441 return is_well_known_klass(k->name()); 442 } 443 static bool is_well_known_klass(Symbol* class_name); 444 #endif 445 446 protected: 447 // Returns the class loader data to be used when looking up/updating the 448 // system dictionary. 449 static ClassLoaderData *class_loader_data(Handle class_loader) { 450 return ClassLoaderData::class_loader_data(class_loader()); 451 } 452 453 public: 454 // Tells whether ClassLoader.checkPackageAccess is present 455 static bool has_checkPackageAccess() { return _has_checkPackageAccess; } 456 457 static bool Parameter_klass_loaded() { return WK_KLASS(reflect_Parameter_klass) != NULL; } 458 static bool Class_klass_loaded() { return WK_KLASS(Class_klass) != NULL; } 459 static bool Cloneable_klass_loaded() { return WK_KLASS(Cloneable_klass) != NULL; } 460 static bool Object_klass_loaded() { return WK_KLASS(Object_klass) != NULL; } 461 static bool ClassLoader_klass_loaded() { return WK_KLASS(ClassLoader_klass) != NULL; } 462 463 // Returns java system loader 464 static oop java_system_loader(); 465 466 // Returns java platform loader 467 static oop java_platform_loader(); 468 469 // Compute the java system and platform loaders 470 static void compute_java_loaders(TRAPS); 471 472 // Register a new class loader 473 static ClassLoaderData* register_loader(Handle class_loader); 474 protected: 475 // Mirrors for primitive classes (created eagerly) 476 static oop check_mirror(oop m) { 477 assert(m != NULL, "mirror not initialized"); 478 return m; 479 } 480 481 public: 482 // Note: java_lang_Class::primitive_type is the inverse of java_mirror 483 484 // Check class loader constraints 485 static bool add_loader_constraint(Symbol* name, Handle loader1, 486 Handle loader2, TRAPS); 487 static Symbol* check_signature_loaders(Symbol* signature, Handle loader1, 488 Handle loader2, bool is_method, TRAPS); 489 490 // JSR 292 491 // find a java.lang.invoke.MethodHandle.invoke* method for a given signature 492 // (asks Java to compute it if necessary, except in a compiler thread) 493 static methodHandle find_method_handle_invoker(Klass* klass, 494 Symbol* name, 495 Symbol* signature, 496 Klass* accessing_klass, 497 Handle *appendix_result, 498 Handle *method_type_result, 499 TRAPS); 500 // for a given signature, find the internal MethodHandle method (linkTo* or invokeBasic) 501 // (does not ask Java, since this is a low-level intrinsic defined by the JVM) 502 static methodHandle find_method_handle_intrinsic(vmIntrinsics::ID iid, 503 Symbol* signature, 504 TRAPS); 505 506 // compute java_mirror (java.lang.Class instance) for a type ("I", "[[B", "LFoo;", etc.) 507 // Either the accessing_klass or the CL/PD can be non-null, but not both. 508 static Handle find_java_mirror_for_type(Symbol* signature, 509 Klass* accessing_klass, 510 Handle class_loader, 511 Handle protection_domain, 512 SignatureStream::FailureMode failure_mode, 513 TRAPS); 514 static Handle find_java_mirror_for_type(Symbol* signature, 515 Klass* accessing_klass, 516 SignatureStream::FailureMode failure_mode, 517 TRAPS) { 518 // callee will fill in CL/PD from AK, if they are needed 519 return find_java_mirror_for_type(signature, accessing_klass, Handle(), Handle(), 520 failure_mode, THREAD); 521 } 522 523 524 // fast short-cut for the one-character case: 525 static oop find_java_mirror_for_type(char signature_char); 526 527 // find a java.lang.invoke.MethodType object for a given signature 528 // (asks Java to compute it if necessary, except in a compiler thread) 529 static Handle find_method_handle_type(Symbol* signature, 530 Klass* accessing_klass, 531 TRAPS); 532 533 // find a java.lang.Class object for a given signature 534 static Handle find_field_handle_type(Symbol* signature, 535 Klass* accessing_klass, 536 TRAPS); 537 538 // ask Java to compute a java.lang.invoke.MethodHandle object for a given CP entry 539 static Handle link_method_handle_constant(Klass* caller, 540 int ref_kind, //e.g., JVM_REF_invokeVirtual 541 Klass* callee, 542 Symbol* name, 543 Symbol* signature, 544 TRAPS); 545 546 // ask Java to compute a constant by invoking a BSM given a Dynamic_info CP entry 547 static Handle link_dynamic_constant(Klass* caller, 548 int condy_index, 549 Handle bootstrap_specifier, 550 Symbol* name, 551 Symbol* type, 552 TRAPS); 553 554 // ask Java to create a dynamic call site, while linking an invokedynamic op 555 static methodHandle find_dynamic_call_site_invoker(Klass* caller, 556 int indy_index, 557 Handle bootstrap_method, 558 Symbol* name, 559 Symbol* type, 560 Handle *appendix_result, 561 Handle *method_type_result, 562 TRAPS); 563 564 // Record the error when the first attempt to resolve a reference from a constant 565 // pool entry to a class fails. 566 static void add_resolution_error(const constantPoolHandle& pool, int which, Symbol* error, 567 Symbol* message); 568 static void delete_resolution_error(ConstantPool* pool); 569 static Symbol* find_resolution_error(const constantPoolHandle& pool, int which, 570 Symbol** message); 571 572 573 static ProtectionDomainCacheEntry* cache_get(Handle protection_domain); 574 575 protected: 576 577 enum Constants { 578 _loader_constraint_size = 107, // number of entries in constraint table 579 _resolution_error_size = 107, // number of entries in resolution error table 580 _invoke_method_size = 139, // number of entries in invoke method table 581 _shared_dictionary_size = 1009, // number of entries in shared dictionary 582 _placeholder_table_size = 1009 // number of entries in hash table for placeholders 583 }; 584 585 586 // Static tables owned by the SystemDictionary 587 588 // Hashtable holding placeholders for classes being loaded. 589 static PlaceholderTable* _placeholders; 590 591 // Hashtable holding classes from the shared archive. 592 static Dictionary* _shared_dictionary; 593 594 // Monotonically increasing counter which grows with 595 // loading classes as well as hot-swapping and breakpoint setting 596 // and removal. 597 static int _number_of_modifications; 598 599 // Lock object for system class loader 600 static oop _system_loader_lock_obj; 601 602 // Constraints on class loaders 603 static LoaderConstraintTable* _loader_constraints; 604 605 // Resolution errors 606 static ResolutionErrorTable* _resolution_errors; 607 608 // Invoke methods (JSR 292) 609 static SymbolPropertyTable* _invoke_method_table; 610 611 // ProtectionDomain cache 612 static ProtectionDomainCacheTable* _pd_cache_table; 613 614 // VM weak OopStorage object. 615 static OopStorage* _vm_weak_oop_storage; 616 617 protected: 618 static void validate_protection_domain(InstanceKlass* klass, 619 Handle class_loader, 620 Handle protection_domain, TRAPS); 621 622 friend class VM_PopulateDumpSharedSpace; 623 friend class TraversePlaceholdersClosure; 624 static Dictionary* shared_dictionary() { return _shared_dictionary; } 625 static PlaceholderTable* placeholders() { return _placeholders; } 626 static LoaderConstraintTable* constraints() { return _loader_constraints; } 627 static ResolutionErrorTable* resolution_errors() { return _resolution_errors; } 628 static SymbolPropertyTable* invoke_method_table() { return _invoke_method_table; } 629 630 // Basic loading operations 631 static InstanceKlass* resolve_instance_class_or_null_helper(Symbol* name, 632 Handle class_loader, 633 Handle protection_domain, 634 TRAPS); 635 static InstanceKlass* resolve_instance_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS); 636 static Klass* resolve_array_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS); 637 static InstanceKlass* handle_parallel_super_load(Symbol* class_name, Symbol* supername, Handle class_loader, Handle protection_domain, Handle lockObject, TRAPS); 638 // Wait on SystemDictionary_lock; unlocks lockObject before 639 // waiting; relocks lockObject with correct recursion count 640 // after waiting, but before reentering SystemDictionary_lock 641 // to preserve lock order semantics. 642 static void double_lock_wait(Handle lockObject, TRAPS); 643 static void define_instance_class(InstanceKlass* k, TRAPS); 644 static InstanceKlass* find_or_define_instance_class(Symbol* class_name, 645 Handle class_loader, 646 InstanceKlass* k, TRAPS); 647 static bool is_shared_class_visible(Symbol* class_name, InstanceKlass* ik, 648 Handle class_loader, TRAPS); 649 static InstanceKlass* load_shared_class(InstanceKlass* ik, 650 Handle class_loader, 651 Handle protection_domain, 652 TRAPS); 653 static InstanceKlass* load_shared_boot_class(Symbol* class_name, 654 TRAPS); 655 static InstanceKlass* load_instance_class(Symbol* class_name, Handle class_loader, TRAPS); 656 static Handle compute_loader_lock_object(Handle class_loader, TRAPS); 657 static void check_loader_lock_contention(Handle loader_lock, TRAPS); 658 static bool is_parallelCapable(Handle class_loader); 659 static bool is_parallelDefine(Handle class_loader); 660 661 public: 662 static bool is_system_class_loader(oop class_loader); 663 static bool is_platform_class_loader(oop class_loader); 664 static void clear_invoke_method_table(); 665 666 // Returns TRUE if the method is a non-public member of class java.lang.Object. 667 static bool is_nonpublic_Object_method(Method* m) { 668 assert(m != NULL, "Unexpected NULL Method*"); 669 return !m->is_public() && m->method_holder() == SystemDictionary::Object_klass(); 670 } 671 672 static void initialize_oop_storage(); 673 static OopStorage* vm_weak_oop_storage(); 674 675 protected: 676 static InstanceKlass* find_shared_class(Symbol* class_name); 677 678 // Setup link to hierarchy 679 static void add_to_hierarchy(InstanceKlass* k, TRAPS); 680 681 // Basic find on loaded classes 682 static InstanceKlass* find_class(unsigned int hash, 683 Symbol* name, Dictionary* dictionary); 684 static InstanceKlass* find_class(Symbol* class_name, ClassLoaderData* loader_data); 685 686 // Basic find on classes in the midst of being loaded 687 static Symbol* find_placeholder(Symbol* name, ClassLoaderData* loader_data); 688 689 // Add a placeholder for a class being loaded 690 static void add_placeholder(int index, 691 Symbol* class_name, 692 ClassLoaderData* loader_data); 693 static void remove_placeholder(int index, 694 Symbol* class_name, 695 ClassLoaderData* loader_data); 696 697 // Performs cleanups after resolve_super_or_fail. This typically needs 698 // to be called on failure. 699 // Won't throw, but can block. 700 static void resolution_cleanups(Symbol* class_name, 701 ClassLoaderData* loader_data, 702 TRAPS); 703 704 // Resolve well-known classes so they can be used like SystemDictionary::String_klass() 705 static void resolve_well_known_classes(TRAPS); 706 707 // Class loader constraints 708 static void check_constraints(unsigned int hash, 709 InstanceKlass* k, Handle loader, 710 bool defining, TRAPS); 711 static void update_dictionary(unsigned int d_hash, 712 int p_index, unsigned int p_hash, 713 InstanceKlass* k, Handle loader, 714 TRAPS); 715 716 static InstanceKlass* _well_known_klasses[]; 717 718 // table of box klasses (int_klass, etc.) 719 static InstanceKlass* _box_klasses[T_VOID+1]; 720 721 private: 722 static oop _java_system_loader; 723 static oop _java_platform_loader; 724 725 static bool _has_checkPackageAccess; 726 }; 727 728 #endif // SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP