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