systemDictionary.hpp revision 13129:da4c9eef4316
1208963Srdivacky/* 2208963Srdivacky * Copyright (c) 1997, 2017, 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 "classfile/systemDictionary_ext.hpp" 30#include "jvmci/systemDictionary_jvmci.hpp" 31#include "oops/objArrayOop.hpp" 32#include "oops/symbol.hpp" 33#include "runtime/java.hpp" 34#include "runtime/reflectionUtils.hpp" 35#include "utilities/hashtable.hpp" 36#include "utilities/hashtable.inline.hpp" 37 38// The system dictionary stores all loaded classes and maps: 39// 40// [class name,class loader] -> class i.e. [Symbol*,oop] -> Klass* 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 with a fixed number 46// of buckets. During loading the loader object is locked, (for the VM loader 47// a private lock object is used). Class loading can thus be done concurrently, 48// but only by different loaders. 49// 50// During loading a placeholder (name, loader) is temporarily placed in 51// a side data structure, and is used to detect ClassCircularityErrors 52// and to perform verification during GC. A GC can occur in the midst 53// of class loading, as we call out to Java, have to take locks, etc. 54// 55// When class loading is finished, a new entry is added to the system 56// dictionary and the place holder is removed. Note that the protection 57// domain field of the system dictionary has not yet been filled in when 58// the "real" system dictionary entry is created. 59// 60// Clients of this class who are interested in finding if a class has 61// been completely loaded -- not classes in the process of being loaded -- 62// can read the SystemDictionary unlocked. This is safe because 63// - entries are only deleted at safepoints 64// - readers cannot come to a safepoint while actively examining 65// an entry (an entry cannot be deleted from under a reader) 66// - entries must be fully formed before they are available to concurrent 67// readers (we must ensure write ordering) 68// 69// Note that placeholders are deleted at any time, as they are removed 70// when a class is completely loaded. Therefore, readers as well as writers 71// of placeholders must hold the SystemDictionary_lock. 72// 73 74class ClassFileStream; 75class Dictionary; 76class PlaceholderTable; 77class LoaderConstraintTable; 78template <MEMFLAGS F> class HashtableBucket; 79class ResolutionErrorTable; 80class SymbolPropertyTable; 81class GCTimer; 82 83// Certain classes are preloaded, such as java.lang.Object and java.lang.String. 84// They are all "well-known", in the sense that no class loader is allowed 85// to provide a different definition. 86// 87// These klasses must all have names defined in vmSymbols. 88 89#define WK_KLASS_ENUM_NAME(kname) kname##_knum 90 91// Each well-known class has a short klass name (like object_klass), 92// a vmSymbol name (like java_lang_Object), and a flag word 93// that makes some minor distinctions, like whether the klass 94// is preloaded, optional, release-specific, etc. 95// The order of these definitions is significant; it is the order in which 96// preloading is actually performed by initialize_preloaded_classes. 97 98#define WK_KLASSES_DO(do_klass) \ 99 /* well-known classes */ \ 100 do_klass(Object_klass, java_lang_Object, Pre ) \ 101 do_klass(String_klass, java_lang_String, Pre ) \ 102 do_klass(Class_klass, java_lang_Class, Pre ) \ 103 do_klass(Cloneable_klass, java_lang_Cloneable, Pre ) \ 104 do_klass(ClassLoader_klass, java_lang_ClassLoader, Pre ) \ 105 do_klass(Serializable_klass, java_io_Serializable, Pre ) \ 106 do_klass(System_klass, java_lang_System, Pre ) \ 107 do_klass(Throwable_klass, java_lang_Throwable, Pre ) \ 108 do_klass(Error_klass, java_lang_Error, Pre ) \ 109 do_klass(ThreadDeath_klass, java_lang_ThreadDeath, Pre ) \ 110 do_klass(Exception_klass, java_lang_Exception, Pre ) \ 111 do_klass(RuntimeException_klass, java_lang_RuntimeException, Pre ) \ 112 do_klass(SecurityManager_klass, java_lang_SecurityManager, Pre ) \ 113 do_klass(ProtectionDomain_klass, java_security_ProtectionDomain, Pre ) \ 114 do_klass(AccessControlContext_klass, java_security_AccessControlContext, Pre ) \ 115 do_klass(SecureClassLoader_klass, java_security_SecureClassLoader, Pre ) \ 116 do_klass(ClassNotFoundException_klass, java_lang_ClassNotFoundException, Pre ) \ 117 do_klass(NoClassDefFoundError_klass, java_lang_NoClassDefFoundError, Pre ) \ 118 do_klass(LinkageError_klass, java_lang_LinkageError, Pre ) \ 119 do_klass(ClassCastException_klass, java_lang_ClassCastException, Pre ) \ 120 do_klass(ArrayStoreException_klass, java_lang_ArrayStoreException, Pre ) \ 121 do_klass(VirtualMachineError_klass, java_lang_VirtualMachineError, Pre ) \ 122 do_klass(OutOfMemoryError_klass, java_lang_OutOfMemoryError, Pre ) \ 123 do_klass(StackOverflowError_klass, java_lang_StackOverflowError, Pre ) \ 124 do_klass(IllegalMonitorStateException_klass, java_lang_IllegalMonitorStateException, Pre ) \ 125 do_klass(Reference_klass, java_lang_ref_Reference, Pre ) \ 126 \ 127 /* Preload ref klasses and set reference types */ \ 128 do_klass(SoftReference_klass, java_lang_ref_SoftReference, Pre ) \ 129 do_klass(WeakReference_klass, java_lang_ref_WeakReference, Pre ) \ 130 do_klass(FinalReference_klass, java_lang_ref_FinalReference, Pre ) \ 131 do_klass(PhantomReference_klass, java_lang_ref_PhantomReference, Pre ) \ 132 do_klass(Finalizer_klass, java_lang_ref_Finalizer, Pre ) \ 133 \ 134 do_klass(Thread_klass, java_lang_Thread, Pre ) \ 135 do_klass(ThreadGroup_klass, java_lang_ThreadGroup, Pre ) \ 136 do_klass(Properties_klass, java_util_Properties, Pre ) \ 137 do_klass(Module_klass, java_lang_Module, Pre ) \ 138 do_klass(reflect_AccessibleObject_klass, java_lang_reflect_AccessibleObject, Pre ) \ 139 do_klass(reflect_Field_klass, java_lang_reflect_Field, Pre ) \ 140 do_klass(reflect_Parameter_klass, java_lang_reflect_Parameter, Opt ) \ 141 do_klass(reflect_Method_klass, java_lang_reflect_Method, Pre ) \ 142 do_klass(reflect_Constructor_klass, java_lang_reflect_Constructor, Pre ) \ 143 \ 144 /* NOTE: needed too early in bootstrapping process to have checks based on JDK version */ \ 145 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \ 146 do_klass(reflect_MagicAccessorImpl_klass, reflect_MagicAccessorImpl, Opt ) \ 147 do_klass(reflect_MethodAccessorImpl_klass, reflect_MethodAccessorImpl, Pre ) \ 148 do_klass(reflect_ConstructorAccessorImpl_klass, reflect_ConstructorAccessorImpl, Pre ) \ 149 do_klass(reflect_DelegatingClassLoader_klass, reflect_DelegatingClassLoader, Opt ) \ 150 do_klass(reflect_ConstantPool_klass, reflect_ConstantPool, Opt ) \ 151 do_klass(reflect_UnsafeStaticFieldAccessorImpl_klass, reflect_UnsafeStaticFieldAccessorImpl, Opt ) \ 152 do_klass(reflect_CallerSensitive_klass, reflect_CallerSensitive, Opt ) \ 153 \ 154 /* support for dynamic typing; it's OK if these are NULL in earlier JDKs */ \ 155 do_klass(DirectMethodHandle_klass, java_lang_invoke_DirectMethodHandle, Opt ) \ 156 do_klass(MethodHandle_klass, java_lang_invoke_MethodHandle, Pre ) \ 157 do_klass(VarHandle_klass, java_lang_invoke_VarHandle, Pre ) \ 158 do_klass(MemberName_klass, java_lang_invoke_MemberName, Pre ) \ 159 do_klass(ResolvedMethodName_klass, java_lang_invoke_ResolvedMethodName, Pre ) \ 160 do_klass(MethodHandleNatives_klass, java_lang_invoke_MethodHandleNatives, Pre ) \ 161 do_klass(LambdaForm_klass, java_lang_invoke_LambdaForm, Opt ) \ 162 do_klass(MethodType_klass, java_lang_invoke_MethodType, Pre ) \ 163 do_klass(BootstrapMethodError_klass, java_lang_BootstrapMethodError, Pre ) \ 164 do_klass(CallSite_klass, java_lang_invoke_CallSite, Pre ) \ 165 do_klass(Context_klass, java_lang_invoke_MethodHandleNatives_CallSiteContext, Pre ) \ 166 do_klass(ConstantCallSite_klass, java_lang_invoke_ConstantCallSite, Pre ) \ 167 do_klass(MutableCallSite_klass, java_lang_invoke_MutableCallSite, Pre ) \ 168 do_klass(VolatileCallSite_klass, java_lang_invoke_VolatileCallSite, Pre ) \ 169 /* Note: MethodHandle must be first, and VolatileCallSite last in group */ \ 170 \ 171 do_klass(StringBuffer_klass, java_lang_StringBuffer, Pre ) \ 172 do_klass(StringBuilder_klass, java_lang_StringBuilder, Pre ) \ 173 do_klass(internal_Unsafe_klass, jdk_internal_misc_Unsafe, Pre ) \ 174 do_klass(module_Modules_klass, jdk_internal_module_Modules, Pre ) \ 175 \ 176 /* support for CDS */ \ 177 do_klass(ByteArrayInputStream_klass, java_io_ByteArrayInputStream, Pre ) \ 178 do_klass(File_klass, java_io_File, Pre ) \ 179 do_klass(URL_klass, java_net_URL, Pre ) \ 180 do_klass(Jar_Manifest_klass, java_util_jar_Manifest, Pre ) \ 181 do_klass(jdk_internal_loader_ClassLoaders_AppClassLoader_klass, jdk_internal_loader_ClassLoaders_AppClassLoader, Pre ) \ 182 do_klass(jdk_internal_loader_ClassLoaders_PlatformClassLoader_klass, jdk_internal_loader_ClassLoaders_PlatformClassLoader, Pre ) \ 183 do_klass(CodeSource_klass, java_security_CodeSource, Pre ) \ 184 do_klass(ParseUtil_klass, sun_net_www_ParseUtil, Pre ) \ 185 \ 186 do_klass(StackTraceElement_klass, java_lang_StackTraceElement, Opt ) \ 187 \ 188 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \ 189 do_klass(nio_Buffer_klass, java_nio_Buffer, Opt ) \ 190 \ 191 /* Stack Walking */ \ 192 do_klass(StackWalker_klass, java_lang_StackWalker, Opt ) \ 193 do_klass(AbstractStackWalker_klass, java_lang_StackStreamFactory_AbstractStackWalker, Opt ) \ 194 do_klass(StackFrameInfo_klass, java_lang_StackFrameInfo, Opt ) \ 195 do_klass(LiveStackFrameInfo_klass, java_lang_LiveStackFrameInfo, Opt ) \ 196 \ 197 /* Preload boxing klasses */ \ 198 do_klass(Boolean_klass, java_lang_Boolean, Pre ) \ 199 do_klass(Character_klass, java_lang_Character, Pre ) \ 200 do_klass(Float_klass, java_lang_Float, Pre ) \ 201 do_klass(Double_klass, java_lang_Double, Pre ) \ 202 do_klass(Byte_klass, java_lang_Byte, Pre ) \ 203 do_klass(Short_klass, java_lang_Short, Pre ) \ 204 do_klass(Integer_klass, java_lang_Integer, Pre ) \ 205 do_klass(Long_klass, java_lang_Long, Pre ) \ 206 \ 207 /* Extensions */ \ 208 WK_KLASSES_DO_EXT(do_klass) \ 209 /* JVMCI classes. These are loaded on-demand. */ \ 210 JVMCI_WK_KLASSES_DO(do_klass) \ 211 \ 212 /*end*/ 213 214 215class SystemDictionary : AllStatic { 216 friend class VMStructs; 217 friend class SystemDictionaryHandles; 218 friend class SharedClassUtil; 219 220 public: 221 enum WKID { 222 NO_WKID = 0, 223 224 #define WK_KLASS_ENUM(name, symbol, ignore_o) WK_KLASS_ENUM_NAME(name), WK_KLASS_ENUM_NAME(symbol) = WK_KLASS_ENUM_NAME(name), 225 WK_KLASSES_DO(WK_KLASS_ENUM) 226 #undef WK_KLASS_ENUM 227 228 WKID_LIMIT, 229 230#if INCLUDE_JVMCI 231 FIRST_JVMCI_WKID = WK_KLASS_ENUM_NAME(JVMCI_klass), 232 LAST_JVMCI_WKID = WK_KLASS_ENUM_NAME(Value_klass), 233#endif 234 235 FIRST_WKID = NO_WKID + 1 236 }; 237 238 enum InitOption { 239 Pre, // preloaded; error if not present 240 241 // Order is significant. Options before this point require resolve_or_fail. 242 // Options after this point will use resolve_or_null instead. 243 244 Opt, // preload tried; NULL if not present 245#if INCLUDE_JVMCI 246 Jvmci, // preload tried; error if not present if JVMCI enabled 247#endif 248 OPTION_LIMIT, 249 CEIL_LG_OPTION_LIMIT = 2 // OPTION_LIMIT <= (1<<CEIL_LG_OPTION_LIMIT) 250 }; 251 252 253 // Returns a class with a given class name and class loader. Loads the 254 // class if needed. If not found a NoClassDefFoundError or a 255 // ClassNotFoundException is thrown, depending on the value on the 256 // throw_error flag. For most uses the throw_error argument should be set 257 // to true. 258 259 static Klass* resolve_or_fail(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS); 260 // Convenient call for null loader and protection domain. 261 static Klass* resolve_or_fail(Symbol* class_name, bool throw_error, TRAPS); 262protected: 263 // handle error translation for resolve_or_null results 264 static Klass* handle_resolution_exception(Symbol* class_name, bool throw_error, Klass* klass, TRAPS); 265 266public: 267 268 // Returns a class with a given class name and class loader. 269 // Loads the class if needed. If not found NULL is returned. 270 static Klass* resolve_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS); 271 // Version with null loader and protection domain 272 static Klass* resolve_or_null(Symbol* class_name, TRAPS); 273 274 // Resolve a superclass or superinterface. Called from ClassFileParser, 275 // parse_interfaces, resolve_instance_class_or_null, load_shared_class 276 // "child_name" is the class whose super class or interface is being resolved. 277 static Klass* resolve_super_or_fail(Symbol* child_name, 278 Symbol* class_name, 279 Handle class_loader, 280 Handle protection_domain, 281 bool is_superclass, 282 TRAPS); 283 284 // Parse new stream. This won't update the system dictionary or 285 // class hierarchy, simply parse the stream. Used by JVMTI RedefineClasses. 286 // Also used by Unsafe_DefineAnonymousClass 287 static InstanceKlass* parse_stream(Symbol* class_name, 288 Handle class_loader, 289 Handle protection_domain, 290 ClassFileStream* st, 291 TRAPS) { 292 return parse_stream(class_name, 293 class_loader, 294 protection_domain, 295 st, 296 NULL, // host klass 297 NULL, // cp_patches 298 THREAD); 299 } 300 static InstanceKlass* parse_stream(Symbol* class_name, 301 Handle class_loader, 302 Handle protection_domain, 303 ClassFileStream* st, 304 const InstanceKlass* host_klass, 305 GrowableArray<Handle>* cp_patches, 306 TRAPS); 307 308 // Resolve from stream (called by jni_DefineClass and JVM_DefineClass) 309 static InstanceKlass* resolve_from_stream(Symbol* class_name, 310 Handle class_loader, 311 Handle protection_domain, 312 ClassFileStream* st, 313 TRAPS); 314 315 // Lookup an already loaded class. If not found NULL is returned. 316 static Klass* find(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS); 317 318 // Lookup an already loaded instance or array class. 319 // Do not make any queries to class loaders; consult only the cache. 320 // If not found NULL is returned. 321 static Klass* find_instance_or_array_klass(Symbol* class_name, 322 Handle class_loader, 323 Handle protection_domain, 324 TRAPS); 325 326 // Lookup an instance or array class that has already been loaded 327 // either into the given class loader, or else into another class 328 // loader that is constrained (via loader constraints) to produce 329 // a consistent class. Do not take protection domains into account. 330 // Do not make any queries to class loaders; consult only the cache. 331 // Return NULL if the class is not found. 332 // 333 // This function is a strict superset of find_instance_or_array_klass. 334 // This function (the unchecked version) makes a conservative prediction 335 // of the result of the checked version, assuming successful lookup. 336 // If both functions return non-null, they must return the same value. 337 // Also, the unchecked version may sometimes be non-null where the 338 // checked version is null. This can occur in several ways: 339 // 1. No query has yet been made to the class loader. 340 // 2. The class loader was queried, but chose not to delegate. 341 // 3. ClassLoader.checkPackageAccess rejected a proposed protection domain. 342 // 4. Loading was attempted, but there was a linkage error of some sort. 343 // In all of these cases, the loader constraints on this type are 344 // satisfied, and it is safe for classes in the given class loader 345 // to manipulate strongly-typed values of the found class, subject 346 // to local linkage and access checks. 347 static Klass* find_constrained_instance_or_array_klass(Symbol* class_name, 348 Handle class_loader, 349 TRAPS); 350 351 // Iterate over all klasses in dictionary 352 // Just the classes from defining class loaders 353 static void classes_do(void f(Klass*)); 354 // Added for initialize_itable_for_klass to handle exceptions 355 static void classes_do(void f(Klass*, TRAPS), TRAPS); 356 // All classes, and their class loaders, including initiating class loaders 357 static void classes_do(void f(Klass*, ClassLoaderData*)); 358 359 // Iterate over all methods in all klasses 360 static void methods_do(void f(Method*)); 361 362 // Garbage collection support 363 364 // This method applies "blk->do_oop" to all the pointers to "system" 365 // classes and loaders. 366 static void always_strong_oops_do(OopClosure* blk); 367 368 // Unload (that is, break root links to) all unmarked classes and 369 // loaders. Returns "true" iff something was unloaded. 370 static bool do_unloading(BoolObjectClosure* is_alive, 371 GCTimer* gc_timer, 372 bool do_cleaning = true); 373 374 // Used by DumpSharedSpaces only to remove classes that failed verification 375 static void remove_classes_in_error_state(); 376 377 static int calculate_systemdictionary_size(int loadedclasses); 378 379 // Applies "f->do_oop" to all root oops in the system dictionary. 380 static void oops_do(OopClosure* f); 381 static void roots_oops_do(OopClosure* strong, OopClosure* weak); 382 383 // System loader lock 384 static oop system_loader_lock() { return _system_loader_lock_obj; } 385 386public: 387 // Sharing support. 388 static void reorder_dictionary(); 389 static void copy_buckets(char** top, char* end); 390 static void copy_table(char** top, char* end); 391 static void set_shared_dictionary(HashtableBucket<mtClass>* t, int length, 392 int number_of_entries); 393 // Printing 394 static void print(bool details = true); 395 static void print_shared(bool details = true); 396 397 // Number of contained klasses 398 // This is both fully loaded classes and classes in the process 399 // of being loaded 400 static int number_of_classes(); 401 402 // Monotonically increasing counter which grows as classes are 403 // loaded or modifications such as hot-swapping or setting/removing 404 // of breakpoints are performed 405 static inline int number_of_modifications() { assert_locked_or_safepoint(Compile_lock); return _number_of_modifications; } 406 // Needed by evolution and breakpoint code 407 static inline void notice_modification() { assert_locked_or_safepoint(Compile_lock); ++_number_of_modifications; } 408 409 // Verification 410 static void verify(); 411 412 // Initialization 413 static void initialize(TRAPS); 414 415 // Checked fast access to commonly used classes - mostly preloaded 416 static InstanceKlass* check_klass(InstanceKlass* k) { 417 assert(k != NULL, "klass not loaded"); 418 return k; 419 } 420 421 static InstanceKlass* check_klass_Pre(InstanceKlass* k) { return check_klass(k); } 422 static InstanceKlass* check_klass_Opt(InstanceKlass* k) { return k; } 423 424 JVMCI_ONLY(static InstanceKlass* check_klass_Jvmci(InstanceKlass* k) { return k; }) 425 426 static bool initialize_wk_klass(WKID id, int init_opt, TRAPS); 427 static void initialize_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS); 428 static void initialize_wk_klasses_through(WKID end_id, WKID &start_id, TRAPS) { 429 int limit = (int)end_id + 1; 430 initialize_wk_klasses_until((WKID) limit, start_id, THREAD); 431 } 432 433public: 434 #define WK_KLASS_DECLARE(name, symbol, option) \ 435 static InstanceKlass* name() { return check_klass_##option(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); } \ 436 static InstanceKlass** name##_addr() { \ 437 return &SystemDictionary::_well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]; \ 438 } 439 WK_KLASSES_DO(WK_KLASS_DECLARE); 440 #undef WK_KLASS_DECLARE 441 442 static InstanceKlass* well_known_klass(WKID id) { 443 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob"); 444 return _well_known_klasses[id]; 445 } 446 447 static InstanceKlass** well_known_klass_addr(WKID id) { 448 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob"); 449 return &_well_known_klasses[id]; 450 } 451 452 // Local definition for direct access to the private array: 453 #define WK_KLASS(name) _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)] 454 455 static InstanceKlass* box_klass(BasicType t) { 456 assert((uint)t < T_VOID+1, "range check"); 457 return check_klass(_box_klasses[t]); 458 } 459 static BasicType box_klass_type(Klass* k); // inverse of box_klass 460 461 // methods returning lazily loaded klasses 462 // The corresponding method to load the class must be called before calling them. 463 static InstanceKlass* abstract_ownable_synchronizer_klass() { return check_klass(_abstract_ownable_synchronizer_klass); } 464 465 static void load_abstract_ownable_synchronizer_klass(TRAPS); 466 467protected: 468 // Tells whether ClassLoader.loadClassInternal is present 469 static bool has_loadClassInternal() { return _has_loadClassInternal; } 470 471 // Returns the class loader data to be used when looking up/updating the 472 // system dictionary. 473 static ClassLoaderData *class_loader_data(Handle class_loader) { 474 return ClassLoaderData::class_loader_data(class_loader()); 475 } 476 477public: 478 // Tells whether ClassLoader.checkPackageAccess is present 479 static bool has_checkPackageAccess() { return _has_checkPackageAccess; } 480 481 static bool Parameter_klass_loaded() { return WK_KLASS(reflect_Parameter_klass) != NULL; } 482 static bool Class_klass_loaded() { return WK_KLASS(Class_klass) != NULL; } 483 static bool Cloneable_klass_loaded() { return WK_KLASS(Cloneable_klass) != NULL; } 484 static bool Object_klass_loaded() { return WK_KLASS(Object_klass) != NULL; } 485 static bool ClassLoader_klass_loaded() { return WK_KLASS(ClassLoader_klass) != NULL; } 486 487 // Returns default system loader 488 static oop java_system_loader(); 489 490 // Compute the default system loader 491 static void compute_java_system_loader(TRAPS); 492 493 // Register a new class loader 494 static ClassLoaderData* register_loader(Handle class_loader, TRAPS); 495protected: 496 // Mirrors for primitive classes (created eagerly) 497 static oop check_mirror(oop m) { 498 assert(m != NULL, "mirror not initialized"); 499 return m; 500 } 501 502public: 503 // Note: java_lang_Class::primitive_type is the inverse of java_mirror 504 505 // Check class loader constraints 506 static bool add_loader_constraint(Symbol* name, Handle loader1, 507 Handle loader2, TRAPS); 508 static Symbol* check_signature_loaders(Symbol* signature, Handle loader1, 509 Handle loader2, bool is_method, TRAPS); 510 511 // JSR 292 512 // find a java.lang.invoke.MethodHandle.invoke* method for a given signature 513 // (asks Java to compute it if necessary, except in a compiler thread) 514 static methodHandle find_method_handle_invoker(Klass* klass, 515 Symbol* name, 516 Symbol* signature, 517 Klass* accessing_klass, 518 Handle *appendix_result, 519 Handle *method_type_result, 520 TRAPS); 521 // for a given signature, find the internal MethodHandle method (linkTo* or invokeBasic) 522 // (does not ask Java, since this is a low-level intrinsic defined by the JVM) 523 static methodHandle find_method_handle_intrinsic(vmIntrinsics::ID iid, 524 Symbol* signature, 525 TRAPS); 526 // find a java.lang.invoke.MethodType object for a given signature 527 // (asks Java to compute it if necessary, except in a compiler thread) 528 static Handle find_method_handle_type(Symbol* signature, 529 Klass* accessing_klass, 530 TRAPS); 531 532 // ask Java to compute a java.lang.invoke.MethodHandle object for a given CP entry 533 static Handle link_method_handle_constant(Klass* caller, 534 int ref_kind, //e.g., JVM_REF_invokeVirtual 535 Klass* callee, 536 Symbol* name, 537 Symbol* signature, 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 Handle bootstrap_method, 543 Symbol* name, 544 Symbol* type, 545 Handle *appendix_result, 546 Handle *method_type_result, 547 TRAPS); 548 549 // Utility for printing loader "name" as part of tracing constraints 550 static const char* loader_name(const oop loader); 551 static const char* loader_name(const ClassLoaderData* loader_data); 552 553 // Record the error when the first attempt to resolve a reference from a constant 554 // pool entry to a class fails. 555 static void add_resolution_error(const constantPoolHandle& pool, int which, Symbol* error, 556 Symbol* message); 557 static void delete_resolution_error(ConstantPool* pool); 558 static Symbol* find_resolution_error(const constantPoolHandle& pool, int which, 559 Symbol** message); 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 _nof_buckets = 1009, // number of buckets in hash table for placeholders 568 _old_default_sdsize = 1009, // backward compat for system dictionary size 569 _prime_array_size = 8, // array of primes for system dictionary size 570 _average_depth_goal = 3 // goal for lookup length 571 }; 572 573 574 // Static variables 575 576 // hashtable sizes for system dictionary to allow growth 577 // prime numbers for system dictionary size 578 static int _sdgeneration; 579 static const int _primelist[_prime_array_size]; 580 581 // Hashtable holding loaded classes. 582 static Dictionary* _dictionary; 583 584 // Hashtable holding placeholders for classes being loaded. 585 static PlaceholderTable* _placeholders; 586 587 // Hashtable holding classes from the shared archive. 588 static Dictionary* _shared_dictionary; 589 590 // Monotonically increasing counter which grows with 591 // _number_of_classes as well as hot-swapping and breakpoint setting 592 // and removal. 593 static int _number_of_modifications; 594 595 // Lock object for system class loader 596 static oop _system_loader_lock_obj; 597 598 // Constraints on class loaders 599 static LoaderConstraintTable* _loader_constraints; 600 601 // Resolution errors 602 static ResolutionErrorTable* _resolution_errors; 603 604 // Invoke methods (JSR 292) 605 static SymbolPropertyTable* _invoke_method_table; 606 607public: 608 // for VM_CounterDecay iteration support 609 friend class CounterDecay; 610 static Klass* try_get_next_class(); 611 612protected: 613 static void validate_protection_domain(InstanceKlass* klass, 614 Handle class_loader, 615 Handle protection_domain, TRAPS); 616 617 friend class VM_PopulateDumpSharedSpace; 618 friend class TraversePlaceholdersClosure; 619 static Dictionary* dictionary() { return _dictionary; } 620 static Dictionary* shared_dictionary() { return _shared_dictionary; } 621 static PlaceholderTable* placeholders() { return _placeholders; } 622 static LoaderConstraintTable* constraints() { return _loader_constraints; } 623 static ResolutionErrorTable* resolution_errors() { return _resolution_errors; } 624 static SymbolPropertyTable* invoke_method_table() { return _invoke_method_table; } 625 626 // Basic loading operations 627 static Klass* resolve_instance_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS); 628 static Klass* resolve_array_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS); 629 static InstanceKlass* handle_parallel_super_load(Symbol* class_name, Symbol* supername, Handle class_loader, Handle protection_domain, Handle lockObject, TRAPS); 630 // Wait on SystemDictionary_lock; unlocks lockObject before 631 // waiting; relocks lockObject with correct recursion count 632 // after waiting, but before reentering SystemDictionary_lock 633 // to preserve lock order semantics. 634 static void double_lock_wait(Handle lockObject, TRAPS); 635 static void define_instance_class(InstanceKlass* k, TRAPS); 636 static InstanceKlass* find_or_define_instance_class(Symbol* class_name, 637 Handle class_loader, 638 InstanceKlass* k, TRAPS); 639 static bool is_shared_class_visible(Symbol* class_name, InstanceKlass* ik, 640 Handle class_loader, TRAPS); 641 static InstanceKlass* load_shared_class(InstanceKlass* ik, 642 Handle class_loader, 643 Handle protection_domain, 644 TRAPS); 645 static InstanceKlass* load_instance_class(Symbol* class_name, Handle class_loader, TRAPS); 646 static Handle compute_loader_lock_object(Handle class_loader, TRAPS); 647 static void check_loader_lock_contention(Handle loader_lock, TRAPS); 648 static bool is_parallelCapable(Handle class_loader); 649 static bool is_parallelDefine(Handle class_loader); 650 651public: 652 static InstanceKlass* load_shared_class(Symbol* class_name, 653 Handle class_loader, 654 TRAPS); 655 static bool is_system_class_loader(oop class_loader); 656 static bool is_platform_class_loader(oop class_loader); 657 658protected: 659 static InstanceKlass* find_shared_class(Symbol* class_name); 660 661 // Setup link to hierarchy 662 static void add_to_hierarchy(InstanceKlass* k, TRAPS); 663 664 // We pass in the hashtable index so we can calculate it outside of 665 // the SystemDictionary_lock. 666 667 // Basic find on loaded classes 668 static InstanceKlass* find_class(int index, unsigned int hash, 669 Symbol* name, ClassLoaderData* loader_data); 670 static InstanceKlass* find_class(Symbol* class_name, ClassLoaderData* loader_data); 671 672 // Basic find on classes in the midst of being loaded 673 static Symbol* find_placeholder(Symbol* name, ClassLoaderData* loader_data); 674 675 // Add a placeholder for a class being loaded 676 static void add_placeholder(int index, 677 Symbol* class_name, 678 ClassLoaderData* loader_data); 679 static void remove_placeholder(int index, 680 Symbol* class_name, 681 ClassLoaderData* loader_data); 682 683 // Performs cleanups after resolve_super_or_fail. This typically needs 684 // to be called on failure. 685 // Won't throw, but can block. 686 static void resolution_cleanups(Symbol* class_name, 687 ClassLoaderData* loader_data, 688 TRAPS); 689 690 // Initialization 691 static void initialize_preloaded_classes(TRAPS); 692 693 // Class loader constraints 694 static void check_constraints(int index, unsigned int hash, 695 InstanceKlass* k, Handle loader, 696 bool defining, TRAPS); 697 static void update_dictionary(int d_index, unsigned int d_hash, 698 int p_index, unsigned int p_hash, 699 InstanceKlass* k, Handle loader, 700 TRAPS); 701 702 // Variables holding commonly used klasses (preloaded) 703 static InstanceKlass* _well_known_klasses[]; 704 705 // Lazily loaded klasses 706 static InstanceKlass* volatile _abstract_ownable_synchronizer_klass; 707 708 // table of box klasses (int_klass, etc.) 709 static InstanceKlass* _box_klasses[T_VOID+1]; 710 711 static oop _java_system_loader; 712 713 static bool _has_loadClassInternal; 714 static bool _has_checkPackageAccess; 715}; 716 717#endif // SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP 718