systemDictionary.hpp revision 9111:a41fe5ffa839
131567Ssef/* 231899Ssef * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved. 331899Ssef * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 431899Ssef * 531899Ssef * This code is free software; you can redistribute it and/or modify it 631899Ssef * under the terms of the GNU General Public License version 2 only, as 731899Ssef * published by the Free Software Foundation. 831899Ssef * 931899Ssef * This code is distributed in the hope that it will be useful, but WITHOUT 1031899Ssef * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 1131899Ssef * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 1231899Ssef * version 2 for more details (a copy is included in the LICENSE file that 1331899Ssef * accompanied this code). 1431899Ssef * 1531899Ssef * You should have received a copy of the GNU General Public License version 1631899Ssef * 2 along with this work; if not, write to the Free Software Foundation, 1731899Ssef * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 1831899Ssef * 1931899Ssef * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 2031899Ssef * or visit www.oracle.com if you need additional information or have any 2131899Ssef * questions. 2231899Ssef * 2331899Ssef */ 2431899Ssef 2531899Ssef#ifndef SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP 2631899Ssef#define SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP 2731899Ssef 2831899Ssef#include "classfile/classFileStream.hpp" 2931899Ssef#include "classfile/classLoader.hpp" 3031899Ssef#include "oops/objArrayOop.hpp" 3131899Ssef#include "oops/symbol.hpp" 3232275Scharnier#include "runtime/java.hpp" 3332275Scharnier#include "runtime/reflectionUtils.hpp" 3450477Speter#include "utilities/hashtable.hpp" 3532275Scharnier#include "utilities/hashtable.inline.hpp" 3632275Scharnier#include "jvmci/systemDictionary_jvmci.hpp" 3731899Ssef 3831567Ssef 3931567Ssef// The system dictionary stores all loaded classes and maps: 4031567Ssef// 4131567Ssef// [class name,class loader] -> class i.e. [Symbol*,oop] -> Klass* 4231567Ssef// 4331567Ssef// Classes are loaded lazily. The default VM class loader is 4431567Ssef// represented as NULL. 4585301Sdes 4685301Sdes// The underlying data structure is an open hash table with a fixed number 4785301Sdes// of buckets. During loading the loader object is locked, (for the VM loader 4885301Sdes// a private lock object is used). Class loading can thus be done concurrently, 4985301Sdes// but only by different loaders. 5085301Sdes// 5185301Sdes// During loading a placeholder (name, loader) is temporarily placed in 5285301Sdes// a side data structure, and is used to detect ClassCircularityErrors 5332275Scharnier// and to perform verification during GC. A GC can occur in the midst 5432275Scharnier// of class loading, as we call out to Java, have to take locks, etc. 5532275Scharnier// 5631567Ssef// When class loading is finished, a new entry is added to the system 5731567Ssef// dictionary and the place holder is removed. Note that the protection 5831567Ssef// domain field of the system dictionary has not yet been filled in when 5931567Ssef// the "real" system dictionary entry is created. 6031567Ssef// 61101282Smdodd// Clients of this class who are interested in finding if a class has 6231567Ssef// been completely loaded -- not classes in the process of being loaded -- 6331567Ssef// can read the SystemDictionary unlocked. This is safe because 6431567Ssef// - entries are only deleted at safepoints 6531567Ssef// - readers cannot come to a safepoint while actively examining 6631567Ssef// an entry (an entry cannot be deleted from under a reader) 6731567Ssef// - entries must be fully formed before they are available to concurrent 6831567Ssef// readers (we must ensure write ordering) 6931567Ssef// 7031567Ssef// Note that placeholders are deleted at any time, as they are removed 7131567Ssef// when a class is completely loaded. Therefore, readers as well as writers 7231567Ssef// of placeholders must hold the SystemDictionary_lock. 7331567Ssef// 7431567Ssef 7531567Ssefclass Dictionary; 7631567Ssefclass PlaceholderTable; 7731567Ssefclass LoaderConstraintTable; 7831567Sseftemplate <MEMFLAGS F> class HashtableBucket; 7931567Ssefclass ResolutionErrorTable; 8031567Ssefclass SymbolPropertyTable; 8131567Ssefclass Ticks; 8231567Ssef 8331567Ssef// Certain classes are preloaded, such as java.lang.Object and java.lang.String. 8431567Ssef// They are all "well-known", in the sense that no class loader is allowed 8531567Ssef// to provide a different definition. 8631567Ssef// 8731567Ssef// These klasses must all have names defined in vmSymbols. 8831567Ssef 8931567Ssef#define WK_KLASS_ENUM_NAME(kname) kname##_knum 9031567Ssef 91100357Smarkm// Each well-known class has a short klass name (like object_klass), 9231567Ssef// a vmSymbol name (like java_lang_Object), and a flag word 9331567Ssef// that makes some minor distinctions, like whether the klass 9431567Ssef// is preloaded, optional, release-specific, etc. 9531567Ssef// The order of these definitions is significant; it is the order in which 9631567Ssef// preloading is actually performed by initialize_preloaded_classes. 9731567Ssef 9831567Ssef#define WK_KLASSES_DO(do_klass) \ 9931567Ssef /* well-known classes */ \ 10031567Ssef do_klass(Object_klass, java_lang_Object, Pre ) \ 10131567Ssef do_klass(String_klass, java_lang_String, Pre ) \ 10231567Ssef do_klass(Class_klass, java_lang_Class, Pre ) \ 10331567Ssef do_klass(Cloneable_klass, java_lang_Cloneable, Pre ) \ 10431567Ssef do_klass(ClassLoader_klass, java_lang_ClassLoader, Pre ) \ 10531567Ssef do_klass(Serializable_klass, java_io_Serializable, Pre ) \ 10631567Ssef do_klass(System_klass, java_lang_System, Pre ) \ 10731567Ssef do_klass(Throwable_klass, java_lang_Throwable, Pre ) \ 10831567Ssef do_klass(Error_klass, java_lang_Error, Pre ) \ 10931567Ssef do_klass(ThreadDeath_klass, java_lang_ThreadDeath, Pre ) \ 11031567Ssef do_klass(Exception_klass, java_lang_Exception, Pre ) \ 11131567Ssef do_klass(RuntimeException_klass, java_lang_RuntimeException, Pre ) \ 11231567Ssef do_klass(SecurityManager_klass, java_lang_SecurityManager, Pre ) \ 11331567Ssef do_klass(ProtectionDomain_klass, java_security_ProtectionDomain, Pre ) \ 114101282Smdodd do_klass(AccessControlContext_klass, java_security_AccessControlContext, Pre ) \ 11531567Ssef do_klass(SecureClassLoader_klass, java_security_SecureClassLoader, Pre ) \ 11631567Ssef do_klass(ClassNotFoundException_klass, java_lang_ClassNotFoundException, Pre ) \ 11731567Ssef do_klass(NoClassDefFoundError_klass, java_lang_NoClassDefFoundError, Pre ) \ 11831567Ssef do_klass(LinkageError_klass, java_lang_LinkageError, Pre ) \ 11931567Ssef do_klass(ClassCastException_klass, java_lang_ClassCastException, Pre ) \ 12031567Ssef do_klass(ArrayStoreException_klass, java_lang_ArrayStoreException, Pre ) \ 12131567Ssef do_klass(VirtualMachineError_klass, java_lang_VirtualMachineError, Pre ) \ 122101282Smdodd do_klass(OutOfMemoryError_klass, java_lang_OutOfMemoryError, Pre ) \ 123101282Smdodd do_klass(StackOverflowError_klass, java_lang_StackOverflowError, Pre ) \ 12431567Ssef do_klass(IllegalMonitorStateException_klass, java_lang_IllegalMonitorStateException, Pre ) \ 12531567Ssef do_klass(Reference_klass, java_lang_ref_Reference, Pre ) \ 126101282Smdodd \ 12731567Ssef /* Preload ref klasses and set reference types */ \ 12831567Ssef do_klass(SoftReference_klass, java_lang_ref_SoftReference, Pre ) \ 129101282Smdodd do_klass(WeakReference_klass, java_lang_ref_WeakReference, Pre ) \ 13031567Ssef do_klass(FinalReference_klass, java_lang_ref_FinalReference, Pre ) \ 13131567Ssef do_klass(PhantomReference_klass, java_lang_ref_PhantomReference, Pre ) \ 13231567Ssef do_klass(Cleaner_klass, sun_misc_Cleaner, Pre ) \ 13331567Ssef do_klass(Finalizer_klass, java_lang_ref_Finalizer, Pre ) \ 13431567Ssef \ 13531567Ssef do_klass(Thread_klass, java_lang_Thread, Pre ) \ 13631567Ssef do_klass(ThreadGroup_klass, java_lang_ThreadGroup, Pre ) \ 13731567Ssef do_klass(Properties_klass, java_util_Properties, Pre ) \ 13831567Ssef do_klass(reflect_AccessibleObject_klass, java_lang_reflect_AccessibleObject, Pre ) \ 13931567Ssef do_klass(reflect_Field_klass, java_lang_reflect_Field, Pre ) \ 14031567Ssef do_klass(reflect_Parameter_klass, java_lang_reflect_Parameter, Opt ) \ 14131567Ssef do_klass(reflect_Method_klass, java_lang_reflect_Method, Pre ) \ 14231567Ssef do_klass(reflect_Constructor_klass, java_lang_reflect_Constructor, Pre ) \ 14331567Ssef \ 14431567Ssef /* NOTE: needed too early in bootstrapping process to have checks based on JDK version */ \ 14531567Ssef /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \ 14631567Ssef do_klass(reflect_MagicAccessorImpl_klass, sun_reflect_MagicAccessorImpl, Opt ) \ 14731567Ssef do_klass(reflect_MethodAccessorImpl_klass, sun_reflect_MethodAccessorImpl, Pre ) \ 14831567Ssef do_klass(reflect_ConstructorAccessorImpl_klass, sun_reflect_ConstructorAccessorImpl, Pre ) \ 14931567Ssef do_klass(reflect_DelegatingClassLoader_klass, sun_reflect_DelegatingClassLoader, Opt ) \ 15031567Ssef do_klass(reflect_ConstantPool_klass, sun_reflect_ConstantPool, Opt ) \ 15131567Ssef do_klass(reflect_UnsafeStaticFieldAccessorImpl_klass, sun_reflect_UnsafeStaticFieldAccessorImpl, Opt ) \ 15231567Ssef do_klass(reflect_CallerSensitive_klass, sun_reflect_CallerSensitive, Opt ) \ 15331567Ssef \ 15431567Ssef /* support for dynamic typing; it's OK if these are NULL in earlier JDKs */ \ 15531567Ssef do_klass(DirectMethodHandle_klass, java_lang_invoke_DirectMethodHandle, Opt ) \ 15631567Ssef do_klass(MethodHandle_klass, java_lang_invoke_MethodHandle, Pre ) \ 15731567Ssef do_klass(MemberName_klass, java_lang_invoke_MemberName, Pre ) \ 15831567Ssef do_klass(MethodHandleNatives_klass, java_lang_invoke_MethodHandleNatives, Pre ) \ 15931567Ssef do_klass(LambdaForm_klass, java_lang_invoke_LambdaForm, Opt ) \ 160101282Smdodd do_klass(MethodType_klass, java_lang_invoke_MethodType, Pre ) \ 16131567Ssef do_klass(BootstrapMethodError_klass, java_lang_BootstrapMethodError, Pre ) \ 16231567Ssef do_klass(CallSite_klass, java_lang_invoke_CallSite, Pre ) \ 16331567Ssef do_klass(Context_klass, java_lang_invoke_MethodHandleNatives_CallSiteContext, Pre ) \ 16431567Ssef do_klass(ConstantCallSite_klass, java_lang_invoke_ConstantCallSite, Pre ) \ 16531567Ssef do_klass(MutableCallSite_klass, java_lang_invoke_MutableCallSite, Pre ) \ 16631567Ssef do_klass(VolatileCallSite_klass, java_lang_invoke_VolatileCallSite, Pre ) \ 16731567Ssef /* Note: MethodHandle must be first, and VolatileCallSite last in group */ \ 16831567Ssef \ 16931567Ssef do_klass(StringBuffer_klass, java_lang_StringBuffer, Pre ) \ 17031567Ssef do_klass(StringBuilder_klass, java_lang_StringBuilder, Pre ) \ 17131567Ssef do_klass(misc_Unsafe_klass, sun_misc_Unsafe, Pre ) \ 17231567Ssef \ 17331567Ssef /* support for CDS */ \ 17431567Ssef do_klass(ByteArrayInputStream_klass, java_io_ByteArrayInputStream, Pre ) \ 17531567Ssef do_klass(File_klass, java_io_File, Pre ) \ 176101282Smdodd do_klass(URLClassLoader_klass, java_net_URLClassLoader, Pre ) \ 17731567Ssef do_klass(URL_klass, java_net_URL, Pre ) \ 17831567Ssef do_klass(Jar_Manifest_klass, java_util_jar_Manifest, Pre ) \ 17931567Ssef do_klass(sun_misc_Launcher_klass, sun_misc_Launcher, Pre ) \ 18031567Ssef do_klass(CodeSource_klass, java_security_CodeSource, Pre ) \ 18131567Ssef \ 18231567Ssef /* It's NULL in non-1.4 JDKs. */ \ 18331567Ssef do_klass(StackTraceElement_klass, java_lang_StackTraceElement, Opt ) \ 18431567Ssef /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \ 18531567Ssef do_klass(nio_Buffer_klass, java_nio_Buffer, Opt ) \ 18631567Ssef \ 18731567Ssef /* Preload boxing klasses */ \ 18831567Ssef do_klass(Boolean_klass, java_lang_Boolean, Pre ) \ 18931567Ssef do_klass(Character_klass, java_lang_Character, Pre ) \ 19031567Ssef do_klass(Float_klass, java_lang_Float, Pre ) \ 19131567Ssef do_klass(Double_klass, java_lang_Double, Pre ) \ 19231567Ssef do_klass(Byte_klass, java_lang_Byte, Pre ) \ 19331567Ssef do_klass(Short_klass, java_lang_Short, Pre ) \ 19431567Ssef do_klass(Integer_klass, java_lang_Integer, Pre ) \ 19531567Ssef do_klass(Long_klass, java_lang_Long, Pre ) \ 19631567Ssef \ 19731567Ssef /* JVMCI classes. These are loaded on-demand. */ \ 19831567Ssef JVMCI_WK_KLASSES_DO(do_klass) \ 19931567Ssef 20031567Ssef /*end*/ 20131567Ssef 20231567Ssef 20331567Ssefclass SystemDictionary : AllStatic { 20431567Ssef friend class VMStructs; 20531567Ssef friend class SystemDictionaryHandles; 20631567Ssef 20731567Ssef public: 20831567Ssef enum WKID { 20931567Ssef NO_WKID = 0, 21031567Ssef 21131567Ssef #define WK_KLASS_ENUM(name, symbol, ignore_o) WK_KLASS_ENUM_NAME(name), WK_KLASS_ENUM_NAME(symbol) = WK_KLASS_ENUM_NAME(name), 21231567Ssef WK_KLASSES_DO(WK_KLASS_ENUM) 21331567Ssef #undef WK_KLASS_ENUM 21431567Ssef 21531567Ssef WKID_LIMIT, 21631567Ssef 217101282Smdodd#if INCLUDE_JVMCI 21831567Ssef FIRST_JVMCI_WKID = WK_KLASS_ENUM_NAME(HotSpotCompiledCode_klass), 21931567Ssef LAST_JVMCI_WKID = WK_KLASS_ENUM_NAME(Value_klass), 22031567Ssef#endif 22131567Ssef 22231567Ssef FIRST_WKID = NO_WKID + 1 22331567Ssef }; 22431567Ssef 22531567Ssef enum InitOption { 22631567Ssef Pre, // preloaded; error if not present 22731567Ssef 228101282Smdodd // Order is significant. Options before this point require resolve_or_fail. 22931567Ssef // Options after this point will use resolve_or_null instead. 23031567Ssef 23131567Ssef Opt, // preload tried; NULL if not present 23231567Ssef#if INCLUDE_JVMCI 23331567Ssef Jvmci, // preload tried; error if not present, use only with JVMCI 23431567Ssef#endif 23531567Ssef OPTION_LIMIT, 23631567Ssef CEIL_LG_OPTION_LIMIT = 2 // OPTION_LIMIT <= (1<<CEIL_LG_OPTION_LIMIT) 23731567Ssef }; 23831567Ssef 23931567Ssef 24031567Ssef // Returns a class with a given class name and class loader. Loads the 241101282Smdodd // class if needed. If not found a NoClassDefFoundError or a 242101282Smdodd // ClassNotFoundException is thrown, depending on the value on the 24331567Ssef // throw_error flag. For most uses the throw_error argument should be set 24431567Ssef // to true. 24531567Ssef 24631567Ssef static Klass* resolve_or_fail(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS); 24731567Ssef // Convenient call for null loader and protection domain. 24831567Ssef static Klass* resolve_or_fail(Symbol* class_name, bool throw_error, TRAPS); 24931567Ssefprotected: 250101282Smdodd // handle error translation for resolve_or_null results 251101282Smdodd static Klass* handle_resolution_exception(Symbol* class_name, bool throw_error, KlassHandle klass_h, TRAPS); 25231567Ssef 25331567Ssefpublic: 254101282Smdodd 25531567Ssef // Returns a class with a given class name and class loader. 25631567Ssef // Loads the class if needed. If not found NULL is returned. 257101282Smdodd static Klass* resolve_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS); 25831567Ssef // Version with null loader and protection domain 25931567Ssef static Klass* resolve_or_null(Symbol* class_name, TRAPS); 26031567Ssef 261101282Smdodd // Resolve a superclass or superinterface. Called from ClassFileParser, 262101282Smdodd // parse_interfaces, resolve_instance_class_or_null, load_shared_class 26331567Ssef // "child_name" is the class whose super class or interface is being resolved. 264101282Smdodd static Klass* resolve_super_or_fail(Symbol* child_name, 26531567Ssef Symbol* class_name, 26631567Ssef Handle class_loader, 26731567Ssef Handle protection_domain, 26831567Ssef bool is_superclass, 26931567Ssef TRAPS); 27031567Ssef 27131567Ssef // Parse new stream. This won't update the system dictionary or 27231567Ssef // class hierarchy, simply parse the stream. Used by JVMTI RedefineClasses. 27331567Ssef static Klass* parse_stream(Symbol* class_name, 27431567Ssef Handle class_loader, 27531567Ssef Handle protection_domain, 27631567Ssef ClassFileStream* st, 27737453Sbde TRAPS) { 27831567Ssef KlassHandle nullHandle; 27931567Ssef return parse_stream(class_name, class_loader, protection_domain, st, nullHandle, NULL, THREAD); 28031567Ssef } 28131567Ssef static Klass* parse_stream(Symbol* class_name, 28231567Ssef Handle class_loader, 28331567Ssef Handle protection_domain, 28431567Ssef ClassFileStream* st, 28531567Ssef KlassHandle host_klass, 28631567Ssef GrowableArray<Handle>* cp_patches, 28731567Ssef TRAPS); 28831567Ssef 28931567Ssef // Resolve from stream (called by jni_DefineClass and JVM_DefineClass) 29031567Ssef static Klass* resolve_from_stream(Symbol* class_name, Handle class_loader, 29131567Ssef Handle protection_domain, 29231567Ssef ClassFileStream* st, bool verify, TRAPS); 29337453Sbde 29431567Ssef // Lookup an already loaded class. If not found NULL is returned. 29531567Ssef static Klass* find(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS); 29631567Ssef 29731567Ssef // Lookup an already loaded instance or array class. 29831567Ssef // Do not make any queries to class loaders; consult only the cache. 29931567Ssef // If not found NULL is returned. 30031567Ssef static Klass* find_instance_or_array_klass(Symbol* class_name, 30131567Ssef Handle class_loader, 30231567Ssef Handle protection_domain, 30331567Ssef TRAPS); 30431567Ssef 30531567Ssef // Lookup an instance or array class that has already been loaded 30631567Ssef // either into the given class loader, or else into another class 307101282Smdodd // loader that is constrained (via loader constraints) to produce 30831567Ssef // a consistent class. Do not take protection domains into account. 30931567Ssef // Do not make any queries to class loaders; consult only the cache. 310101282Smdodd // Return NULL if the class is not found. 31131567Ssef // 312 // This function is a strict superset of find_instance_or_array_klass. 313 // This function (the unchecked version) makes a conservative prediction 314 // of the result of the checked version, assuming successful lookup. 315 // If both functions return non-null, they must return the same value. 316 // Also, the unchecked version may sometimes be non-null where the 317 // checked version is null. This can occur in several ways: 318 // 1. No query has yet been made to the class loader. 319 // 2. The class loader was queried, but chose not to delegate. 320 // 3. ClassLoader.checkPackageAccess rejected a proposed protection domain. 321 // 4. Loading was attempted, but there was a linkage error of some sort. 322 // In all of these cases, the loader constraints on this type are 323 // satisfied, and it is safe for classes in the given class loader 324 // to manipulate strongly-typed values of the found class, subject 325 // to local linkage and access checks. 326 static Klass* find_constrained_instance_or_array_klass(Symbol* class_name, 327 Handle class_loader, 328 TRAPS); 329 330 // Iterate over all klasses in dictionary 331 // Just the classes from defining class loaders 332 static void classes_do(void f(Klass*)); 333 // Added for initialize_itable_for_klass to handle exceptions 334 static void classes_do(void f(Klass*, TRAPS), TRAPS); 335 // All classes, and their class loaders 336 static void classes_do(void f(Klass*, ClassLoaderData*)); 337 338 static void placeholders_do(void f(Symbol*)); 339 340 // Iterate over all methods in all klasses in dictionary 341 static void methods_do(void f(Method*)); 342 343 // Garbage collection support 344 345 // This method applies "blk->do_oop" to all the pointers to "system" 346 // classes and loaders. 347 static void always_strong_oops_do(OopClosure* blk); 348 static void always_strong_classes_do(KlassClosure* closure); 349 350 // Unload (that is, break root links to) all unmarked classes and 351 // loaders. Returns "true" iff something was unloaded. 352 static bool do_unloading(BoolObjectClosure* is_alive, 353 bool clean_previous_versions = true); 354 355 // Used by DumpSharedSpaces only to remove classes that failed verification 356 static void remove_classes_in_error_state(); 357 358 static int calculate_systemdictionary_size(int loadedclasses); 359 360 // Applies "f->do_oop" to all root oops in the system dictionary. 361 static void oops_do(OopClosure* f); 362 static void roots_oops_do(OopClosure* strong, OopClosure* weak); 363 364 // System loader lock 365 static oop system_loader_lock() { return _system_loader_lock_obj; } 366 367protected: 368 // Extended Redefine classes support (tbi) 369 static void preloaded_classes_do(KlassClosure* f); 370 static void lazily_loaded_classes_do(KlassClosure* f); 371public: 372 // Sharing support. 373 static void reorder_dictionary(); 374 static void copy_buckets(char** top, char* end); 375 static void copy_table(char** top, char* end); 376 static void reverse(); 377 static void set_shared_dictionary(HashtableBucket<mtClass>* t, int length, 378 int number_of_entries); 379 // Printing 380 static void print(bool details = true); 381 static void print_shared(bool details = true); 382 383 // Number of contained klasses 384 // This is both fully loaded classes and classes in the process 385 // of being loaded 386 static int number_of_classes(); 387 388 // Monotonically increasing counter which grows as classes are 389 // loaded or modifications such as hot-swapping or setting/removing 390 // of breakpoints are performed 391 static inline int number_of_modifications() { assert_locked_or_safepoint(Compile_lock); return _number_of_modifications; } 392 // Needed by evolution and breakpoint code 393 static inline void notice_modification() { assert_locked_or_safepoint(Compile_lock); ++_number_of_modifications; } 394 395 // Verification 396 static void verify(); 397 398#ifdef ASSERT 399 static bool is_internal_format(Symbol* class_name); 400#endif 401 402 // Initialization 403 static void initialize(TRAPS); 404 405 // Fast access to commonly used classes (preloaded) 406 static Klass* check_klass(Klass* k) { 407 assert(k != NULL, "preloaded klass not initialized"); 408 return k; 409 } 410 411 static Klass* check_klass_Pre( Klass* k) { return check_klass(k); } 412 static Klass* check_klass_Opt( Klass* k) { return k; } 413 414 JVMCI_ONLY(static Klass* check_klass_Jvmci(Klass* k) { return k; }) 415 416 static bool initialize_wk_klass(WKID id, int init_opt, TRAPS); 417 static void initialize_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS); 418 static void initialize_wk_klasses_through(WKID end_id, WKID &start_id, TRAPS) { 419 int limit = (int)end_id + 1; 420 initialize_wk_klasses_until((WKID) limit, start_id, THREAD); 421 } 422 423public: 424 #define WK_KLASS_DECLARE(name, symbol, option) \ 425 static Klass* name() { return check_klass_##option(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); } \ 426 static Klass** name##_addr() { \ 427 return &SystemDictionary::_well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]; \ 428 } 429 WK_KLASSES_DO(WK_KLASS_DECLARE); 430 #undef WK_KLASS_DECLARE 431 432 static Klass* well_known_klass(WKID id) { 433 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob"); 434 return _well_known_klasses[id]; 435 } 436 437 static Klass** well_known_klass_addr(WKID id) { 438 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob"); 439 return &_well_known_klasses[id]; 440 } 441 442 // Local definition for direct access to the private array: 443 #define WK_KLASS(name) _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)] 444 445 static Klass* box_klass(BasicType t) { 446 assert((uint)t < T_VOID+1, "range check"); 447 return check_klass(_box_klasses[t]); 448 } 449 static BasicType box_klass_type(Klass* k); // inverse of box_klass 450 451 // methods returning lazily loaded klasses 452 // The corresponding method to load the class must be called before calling them. 453 static Klass* abstract_ownable_synchronizer_klass() { return check_klass(_abstract_ownable_synchronizer_klass); } 454 455 static void load_abstract_ownable_synchronizer_klass(TRAPS); 456 457protected: 458 // Tells whether ClassLoader.loadClassInternal is present 459 static bool has_loadClassInternal() { return _has_loadClassInternal; } 460 461 // Returns the class loader data to be used when looking up/updating the 462 // system dictionary. 463 static ClassLoaderData *class_loader_data(Handle class_loader) { 464 return ClassLoaderData::class_loader_data(class_loader()); 465 } 466 467public: 468 // Tells whether ClassLoader.checkPackageAccess is present 469 static bool has_checkPackageAccess() { return _has_checkPackageAccess; } 470 471 static bool Parameter_klass_loaded() { return WK_KLASS(reflect_Parameter_klass) != NULL; } 472 static bool Class_klass_loaded() { return WK_KLASS(Class_klass) != NULL; } 473 static bool Cloneable_klass_loaded() { return WK_KLASS(Cloneable_klass) != NULL; } 474 static bool Object_klass_loaded() { return WK_KLASS(Object_klass) != NULL; } 475 static bool ClassLoader_klass_loaded() { return WK_KLASS(ClassLoader_klass) != NULL; } 476 477 // Returns default system loader 478 static oop java_system_loader(); 479 480 // Compute the default system loader 481 static void compute_java_system_loader(TRAPS); 482 483 // Register a new class loader 484 static ClassLoaderData* register_loader(Handle class_loader, TRAPS); 485protected: 486 // Mirrors for primitive classes (created eagerly) 487 static oop check_mirror(oop m) { 488 assert(m != NULL, "mirror not initialized"); 489 return m; 490 } 491 492public: 493 // Note: java_lang_Class::primitive_type is the inverse of java_mirror 494 495 // Check class loader constraints 496 static bool add_loader_constraint(Symbol* name, Handle loader1, 497 Handle loader2, TRAPS); 498 static Symbol* check_signature_loaders(Symbol* signature, Handle loader1, 499 Handle loader2, bool is_method, TRAPS); 500 501 // JSR 292 502 // find a java.lang.invoke.MethodHandle.invoke* method for a given signature 503 // (asks Java to compute it if necessary, except in a compiler thread) 504 static methodHandle find_method_handle_invoker(Symbol* name, 505 Symbol* signature, 506 KlassHandle accessing_klass, 507 Handle *appendix_result, 508 Handle *method_type_result, 509 TRAPS); 510 // for a given signature, find the internal MethodHandle method (linkTo* or invokeBasic) 511 // (does not ask Java, since this is a low-level intrinsic defined by the JVM) 512 static methodHandle find_method_handle_intrinsic(vmIntrinsics::ID iid, 513 Symbol* signature, 514 TRAPS); 515 // find a java.lang.invoke.MethodType object for a given signature 516 // (asks Java to compute it if necessary, except in a compiler thread) 517 static Handle find_method_handle_type(Symbol* signature, 518 KlassHandle accessing_klass, 519 TRAPS); 520 521 // ask Java to compute a java.lang.invoke.MethodHandle object for a given CP entry 522 static Handle link_method_handle_constant(KlassHandle caller, 523 int ref_kind, //e.g., JVM_REF_invokeVirtual 524 KlassHandle callee, 525 Symbol* name, 526 Symbol* signature, 527 TRAPS); 528 529 // ask Java to create a dynamic call site, while linking an invokedynamic op 530 static methodHandle find_dynamic_call_site_invoker(KlassHandle caller, 531 Handle bootstrap_method, 532 Symbol* name, 533 Symbol* type, 534 Handle *appendix_result, 535 Handle *method_type_result, 536 TRAPS); 537 538 // Utility for printing loader "name" as part of tracing constraints 539 static const char* loader_name(oop loader) { 540 return ((loader) == NULL ? "<bootloader>" : 541 InstanceKlass::cast((loader)->klass())->name()->as_C_string() ); 542 } 543 static const char* loader_name(ClassLoaderData* loader_data) { 544 return (loader_data->class_loader() == NULL ? "<bootloader>" : 545 InstanceKlass::cast((loader_data->class_loader())->klass())->name()->as_C_string() ); 546 } 547 548 // Record the error when the first attempt to resolve a reference from a constant 549 // pool entry to a class fails. 550 static void add_resolution_error(constantPoolHandle pool, int which, Symbol* error, 551 Symbol* message); 552 static void delete_resolution_error(ConstantPool* pool); 553 static Symbol* find_resolution_error(constantPoolHandle pool, int which, 554 Symbol** message); 555 556 protected: 557 558 enum Constants { 559 _loader_constraint_size = 107, // number of entries in constraint table 560 _resolution_error_size = 107, // number of entries in resolution error table 561 _invoke_method_size = 139, // number of entries in invoke method table 562 _nof_buckets = 1009, // number of buckets in hash table for placeholders 563 _old_default_sdsize = 1009, // backward compat for system dictionary size 564 _prime_array_size = 8, // array of primes for system dictionary size 565 _average_depth_goal = 3 // goal for lookup length 566 }; 567 568 569 // Static variables 570 571 // hashtable sizes for system dictionary to allow growth 572 // prime numbers for system dictionary size 573 static int _sdgeneration; 574 static const int _primelist[_prime_array_size]; 575 576 // Hashtable holding loaded classes. 577 static Dictionary* _dictionary; 578 579 // Hashtable holding placeholders for classes being loaded. 580 static PlaceholderTable* _placeholders; 581 582 // Hashtable holding classes from the shared archive. 583 static Dictionary* _shared_dictionary; 584 585 // Monotonically increasing counter which grows with 586 // _number_of_classes as well as hot-swapping and breakpoint setting 587 // and removal. 588 static int _number_of_modifications; 589 590 // Lock object for system class loader 591 static oop _system_loader_lock_obj; 592 593 // Constraints on class loaders 594 static LoaderConstraintTable* _loader_constraints; 595 596 // Resolution errors 597 static ResolutionErrorTable* _resolution_errors; 598 599 // Invoke methods (JSR 292) 600 static SymbolPropertyTable* _invoke_method_table; 601 602public: 603 // for VM_CounterDecay iteration support 604 friend class CounterDecay; 605 static Klass* try_get_next_class(); 606 607protected: 608 static void validate_protection_domain(instanceKlassHandle klass, 609 Handle class_loader, 610 Handle protection_domain, TRAPS); 611 612 friend class VM_PopulateDumpSharedSpace; 613 friend class TraversePlaceholdersClosure; 614 static Dictionary* dictionary() { return _dictionary; } 615 static Dictionary* shared_dictionary() { return _shared_dictionary; } 616 static PlaceholderTable* placeholders() { return _placeholders; } 617 static LoaderConstraintTable* constraints() { return _loader_constraints; } 618 static ResolutionErrorTable* resolution_errors() { return _resolution_errors; } 619 static SymbolPropertyTable* invoke_method_table() { return _invoke_method_table; } 620 621 // Basic loading operations 622 static Klass* resolve_instance_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS); 623 static Klass* resolve_array_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS); 624 static instanceKlassHandle handle_parallel_super_load(Symbol* class_name, Symbol* supername, Handle class_loader, Handle protection_domain, Handle lockObject, TRAPS); 625 // Wait on SystemDictionary_lock; unlocks lockObject before 626 // waiting; relocks lockObject with correct recursion count 627 // after waiting, but before reentering SystemDictionary_lock 628 // to preserve lock order semantics. 629 static void double_lock_wait(Handle lockObject, TRAPS); 630 static void define_instance_class(instanceKlassHandle k, TRAPS); 631 static instanceKlassHandle find_or_define_instance_class(Symbol* class_name, 632 Handle class_loader, 633 instanceKlassHandle k, TRAPS); 634 static instanceKlassHandle load_shared_class(instanceKlassHandle ik, 635 Handle class_loader, 636 Handle protection_domain, 637 TRAPS); 638 static instanceKlassHandle load_instance_class(Symbol* class_name, Handle class_loader, TRAPS); 639 static Handle compute_loader_lock_object(Handle class_loader, TRAPS); 640 static void check_loader_lock_contention(Handle loader_lock, TRAPS); 641 static bool is_parallelCapable(Handle class_loader); 642 static bool is_parallelDefine(Handle class_loader); 643 644public: 645 static instanceKlassHandle load_shared_class(Symbol* class_name, 646 Handle class_loader, 647 TRAPS); 648 static bool is_ext_class_loader(Handle class_loader); 649 650protected: 651 static Klass* find_shared_class(Symbol* class_name); 652 653 // Setup link to hierarchy 654 static void add_to_hierarchy(instanceKlassHandle k, TRAPS); 655 656 // event based tracing 657 static void post_class_load_event(const Ticks& start_time, instanceKlassHandle k, 658 Handle initiating_loader); 659 // We pass in the hashtable index so we can calculate it outside of 660 // the SystemDictionary_lock. 661 662 // Basic find on loaded classes 663 static Klass* find_class(int index, unsigned int hash, 664 Symbol* name, ClassLoaderData* loader_data); 665 static Klass* find_class(Symbol* class_name, ClassLoaderData* loader_data); 666 667 // Basic find on classes in the midst of being loaded 668 static Symbol* find_placeholder(Symbol* name, ClassLoaderData* loader_data); 669 670 // Updating entry in dictionary 671 // Add a completely loaded class 672 static void add_klass(int index, Symbol* class_name, 673 ClassLoaderData* loader_data, KlassHandle obj); 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 instanceKlassHandle 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 instanceKlassHandle k, Handle loader, 700 TRAPS); 701 702 // Variables holding commonly used klasses (preloaded) 703 static Klass* _well_known_klasses[]; 704 705 // Lazily loaded klasses 706 static Klass* volatile _abstract_ownable_synchronizer_klass; 707 708 // table of box klasses (int_klass, etc.) 709 static Klass* _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