annotate src/share/vm/classfile/systemDictionary.hpp @ 6465:2c6ef90f030a

8049421: G1 Class Unloading after completing a concurrent mark cycle Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com
author stefank
date Mon, 07 Jul 2014 10:12:40 +0200
parents 9428a0b94204
children 6e0cb14ce59b
rev   line source
duke@0 1 /*
coleenp@5881 2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
duke@0 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@0 4 *
duke@0 5 * This code is free software; you can redistribute it and/or modify it
duke@0 6 * under the terms of the GNU General Public License version 2 only, as
duke@0 7 * published by the Free Software Foundation.
duke@0 8 *
duke@0 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@0 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@0 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@0 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@0 13 * accompanied this code).
duke@0 14 *
duke@0 15 * You should have received a copy of the GNU General Public License version
duke@0 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@0 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@0 18 *
trims@1472 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1472 20 * or visit www.oracle.com if you need additional information or have any
trims@1472 21 * questions.
duke@0 22 *
duke@0 23 */
duke@0 24
stefank@1879 25 #ifndef SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP
stefank@1879 26 #define SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP
stefank@1879 27
stefank@1879 28 #include "classfile/classFileStream.hpp"
stefank@1879 29 #include "classfile/classLoader.hpp"
stefank@1879 30 #include "oops/objArrayOop.hpp"
coleenp@2062 31 #include "oops/symbol.hpp"
stefank@1879 32 #include "runtime/java.hpp"
stefank@1879 33 #include "runtime/reflectionUtils.hpp"
stefank@1879 34 #include "utilities/hashtable.hpp"
zgu@3465 35 #include "utilities/hashtable.inline.hpp"
stefank@1879 36
sla@4802 37
duke@0 38 // The system dictionary stores all loaded classes and maps:
duke@0 39 //
coleenp@3602 40 // [class name,class loader] -> class i.e. [Symbol*,oop] -> Klass*
duke@0 41 //
duke@0 42 // Classes are loaded lazily. The default VM class loader is
duke@0 43 // represented as NULL.
duke@0 44
duke@0 45 // The underlying data structure is an open hash table with a fixed number
duke@0 46 // of buckets. During loading the loader object is locked, (for the VM loader
duke@0 47 // a private lock object is used). Class loading can thus be done concurrently,
duke@0 48 // but only by different loaders.
duke@0 49 //
duke@0 50 // During loading a placeholder (name, loader) is temporarily placed in
duke@0 51 // a side data structure, and is used to detect ClassCircularityErrors
duke@0 52 // and to perform verification during GC. A GC can occur in the midst
duke@0 53 // of class loading, as we call out to Java, have to take locks, etc.
duke@0 54 //
duke@0 55 // When class loading is finished, a new entry is added to the system
duke@0 56 // dictionary and the place holder is removed. Note that the protection
duke@0 57 // domain field of the system dictionary has not yet been filled in when
duke@0 58 // the "real" system dictionary entry is created.
duke@0 59 //
duke@0 60 // Clients of this class who are interested in finding if a class has
duke@0 61 // been completely loaded -- not classes in the process of being loaded --
duke@0 62 // can read the SystemDictionary unlocked. This is safe because
duke@0 63 // - entries are only deleted at safepoints
duke@0 64 // - readers cannot come to a safepoint while actively examining
duke@0 65 // an entry (an entry cannot be deleted from under a reader)
duke@0 66 // - entries must be fully formed before they are available to concurrent
duke@0 67 // readers (we must ensure write ordering)
duke@0 68 //
duke@0 69 // Note that placeholders are deleted at any time, as they are removed
duke@0 70 // when a class is completely loaded. Therefore, readers as well as writers
duke@0 71 // of placeholders must hold the SystemDictionary_lock.
duke@0 72 //
duke@0 73
duke@0 74 class Dictionary;
duke@0 75 class PlaceholderTable;
duke@0 76 class LoaderConstraintTable;
zgu@3465 77 template <MEMFLAGS F> class HashtableBucket;
duke@0 78 class ResolutionErrorTable;
jrose@710 79 class SymbolPropertyTable;
mgronlun@5696 80 class Ticks;
duke@0 81
jrose@132 82 // Certain classes are preloaded, such as java.lang.Object and java.lang.String.
jrose@132 83 // They are all "well-known", in the sense that no class loader is allowed
jrose@132 84 // to provide a different definition.
jrose@132 85 //
jrose@132 86 // These klasses must all have names defined in vmSymbols.
jrose@132 87
jrose@132 88 #define WK_KLASS_ENUM_NAME(kname) kname##_knum
jrose@132 89
jrose@132 90 // Each well-known class has a short klass name (like object_klass),
jrose@132 91 // a vmSymbol name (like java_lang_Object), and a flag word
jrose@132 92 // that makes some minor distinctions, like whether the klass
jrose@132 93 // is preloaded, optional, release-specific, etc.
jrose@132 94 // The order of these definitions is significant; it is the order in which
jrose@132 95 // preloading is actually performed by initialize_preloaded_classes.
jrose@132 96
twisti@3723 97 #define WK_KLASSES_DO(do_klass) \
twisti@3723 98 /* well-known classes */ \
twisti@3728 99 do_klass(Object_klass, java_lang_Object, Pre ) \
twisti@3728 100 do_klass(String_klass, java_lang_String, Pre ) \
twisti@3728 101 do_klass(Class_klass, java_lang_Class, Pre ) \
twisti@3728 102 do_klass(Cloneable_klass, java_lang_Cloneable, Pre ) \
twisti@3728 103 do_klass(ClassLoader_klass, java_lang_ClassLoader, Pre ) \
twisti@3728 104 do_klass(Serializable_klass, java_io_Serializable, Pre ) \
twisti@3728 105 do_klass(System_klass, java_lang_System, Pre ) \
twisti@3728 106 do_klass(Throwable_klass, java_lang_Throwable, Pre ) \
twisti@3728 107 do_klass(Error_klass, java_lang_Error, Pre ) \
twisti@3728 108 do_klass(ThreadDeath_klass, java_lang_ThreadDeath, Pre ) \
twisti@3728 109 do_klass(Exception_klass, java_lang_Exception, Pre ) \
twisti@3728 110 do_klass(RuntimeException_klass, java_lang_RuntimeException, Pre ) \
twisti@4431 111 do_klass(SecurityManager_klass, java_lang_SecurityManager, Pre ) \
twisti@3728 112 do_klass(ProtectionDomain_klass, java_security_ProtectionDomain, Pre ) \
twisti@3728 113 do_klass(AccessControlContext_klass, java_security_AccessControlContext, Pre ) \
twisti@3728 114 do_klass(ClassNotFoundException_klass, java_lang_ClassNotFoundException, Pre ) \
twisti@3728 115 do_klass(NoClassDefFoundError_klass, java_lang_NoClassDefFoundError, Pre ) \
twisti@3728 116 do_klass(LinkageError_klass, java_lang_LinkageError, Pre ) \
twisti@3728 117 do_klass(ClassCastException_klass, java_lang_ClassCastException, Pre ) \
twisti@3728 118 do_klass(ArrayStoreException_klass, java_lang_ArrayStoreException, Pre ) \
twisti@3728 119 do_klass(VirtualMachineError_klass, java_lang_VirtualMachineError, Pre ) \
twisti@3728 120 do_klass(OutOfMemoryError_klass, java_lang_OutOfMemoryError, Pre ) \
twisti@3728 121 do_klass(StackOverflowError_klass, java_lang_StackOverflowError, Pre ) \
twisti@3728 122 do_klass(IllegalMonitorStateException_klass, java_lang_IllegalMonitorStateException, Pre ) \
twisti@3728 123 do_klass(Reference_klass, java_lang_ref_Reference, Pre ) \
twisti@3723 124 \
twisti@3723 125 /* Preload ref klasses and set reference types */ \
twisti@3728 126 do_klass(SoftReference_klass, java_lang_ref_SoftReference, Pre ) \
twisti@3728 127 do_klass(WeakReference_klass, java_lang_ref_WeakReference, Pre ) \
twisti@3723 128 do_klass(FinalReference_klass, java_lang_ref_FinalReference, Pre ) \
twisti@3728 129 do_klass(PhantomReference_klass, java_lang_ref_PhantomReference, Pre ) \
twisti@3723 130 do_klass(Finalizer_klass, java_lang_ref_Finalizer, Pre ) \
twisti@3723 131 \
twisti@3728 132 do_klass(Thread_klass, java_lang_Thread, Pre ) \
twisti@3728 133 do_klass(ThreadGroup_klass, java_lang_ThreadGroup, Pre ) \
twisti@3728 134 do_klass(Properties_klass, java_util_Properties, Pre ) \
twisti@3728 135 do_klass(reflect_AccessibleObject_klass, java_lang_reflect_AccessibleObject, Pre ) \
twisti@3728 136 do_klass(reflect_Field_klass, java_lang_reflect_Field, Pre ) \
coleenp@3963 137 do_klass(reflect_Parameter_klass, java_lang_reflect_Parameter, Opt ) \
twisti@3728 138 do_klass(reflect_Method_klass, java_lang_reflect_Method, Pre ) \
twisti@3728 139 do_klass(reflect_Constructor_klass, java_lang_reflect_Constructor, Pre ) \
twisti@3723 140 \
never@2702 141 /* NOTE: needed too early in bootstrapping process to have checks based on JDK version */ \
never@2702 142 /* Universe::is_gte_jdk14x_version() is not set up by this point. */ \
never@2702 143 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \
twisti@3723 144 do_klass(reflect_MagicAccessorImpl_klass, sun_reflect_MagicAccessorImpl, Opt ) \
twisti@3723 145 do_klass(reflect_MethodAccessorImpl_klass, sun_reflect_MethodAccessorImpl, Opt_Only_JDK14NewRef) \
twisti@3723 146 do_klass(reflect_ConstructorAccessorImpl_klass, sun_reflect_ConstructorAccessorImpl, Opt_Only_JDK14NewRef) \
twisti@3723 147 do_klass(reflect_DelegatingClassLoader_klass, sun_reflect_DelegatingClassLoader, Opt ) \
twisti@3723 148 do_klass(reflect_ConstantPool_klass, sun_reflect_ConstantPool, Opt_Only_JDK15 ) \
twisti@3723 149 do_klass(reflect_UnsafeStaticFieldAccessorImpl_klass, sun_reflect_UnsafeStaticFieldAccessorImpl, Opt_Only_JDK15 ) \
twisti@4431 150 do_klass(reflect_CallerSensitive_klass, sun_reflect_CallerSensitive, Opt ) \
twisti@3723 151 \
twisti@3723 152 /* support for dynamic typing; it's OK if these are NULL in earlier JDKs */ \
sspitsyn@5061 153 do_klass(DirectMethodHandle_klass, java_lang_invoke_DirectMethodHandle, Opt ) \
twisti@3728 154 do_klass(MethodHandle_klass, java_lang_invoke_MethodHandle, Pre_JSR292 ) \
twisti@3728 155 do_klass(MemberName_klass, java_lang_invoke_MemberName, Pre_JSR292 ) \
twisti@3728 156 do_klass(MethodHandleNatives_klass, java_lang_invoke_MethodHandleNatives, Pre_JSR292 ) \
twisti@3723 157 do_klass(LambdaForm_klass, java_lang_invoke_LambdaForm, Opt ) \
twisti@3728 158 do_klass(MethodType_klass, java_lang_invoke_MethodType, Pre_JSR292 ) \
twisti@3728 159 do_klass(BootstrapMethodError_klass, java_lang_BootstrapMethodError, Pre_JSR292 ) \
twisti@3728 160 do_klass(CallSite_klass, java_lang_invoke_CallSite, Pre_JSR292 ) \
twisti@3728 161 do_klass(ConstantCallSite_klass, java_lang_invoke_ConstantCallSite, Pre_JSR292 ) \
twisti@3728 162 do_klass(MutableCallSite_klass, java_lang_invoke_MutableCallSite, Pre_JSR292 ) \
twisti@3728 163 do_klass(VolatileCallSite_klass, java_lang_invoke_VolatileCallSite, Pre_JSR292 ) \
twisti@3723 164 /* Note: MethodHandle must be first, and VolatileCallSite last in group */ \
twisti@3723 165 \
twisti@3728 166 do_klass(StringBuffer_klass, java_lang_StringBuffer, Pre ) \
twisti@3728 167 do_klass(StringBuilder_klass, java_lang_StringBuilder, Pre ) \
drchase@5699 168 do_klass(misc_Unsafe_klass, sun_misc_Unsafe, Pre ) \
twisti@3723 169 \
twisti@3723 170 /* It's NULL in non-1.4 JDKs. */ \
twisti@3723 171 do_klass(StackTraceElement_klass, java_lang_StackTraceElement, Opt ) \
twisti@3723 172 /* Universe::is_gte_jdk14x_version() is not set up by this point. */ \
twisti@3723 173 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \
twisti@3723 174 do_klass(nio_Buffer_klass, java_nio_Buffer, Opt ) \
twisti@3723 175 \
twisti@3723 176 /* Preload boxing klasses */ \
twisti@3728 177 do_klass(Boolean_klass, java_lang_Boolean, Pre ) \
twisti@3728 178 do_klass(Character_klass, java_lang_Character, Pre ) \
twisti@3728 179 do_klass(Float_klass, java_lang_Float, Pre ) \
twisti@3728 180 do_klass(Double_klass, java_lang_Double, Pre ) \
twisti@3728 181 do_klass(Byte_klass, java_lang_Byte, Pre ) \
twisti@3728 182 do_klass(Short_klass, java_lang_Short, Pre ) \
twisti@3728 183 do_klass(Integer_klass, java_lang_Integer, Pre ) \
twisti@3728 184 do_klass(Long_klass, java_lang_Long, Pre ) \
jrose@132 185 /*end*/
jrose@132 186
jrose@132 187
duke@0 188 class SystemDictionary : AllStatic {
duke@0 189 friend class VMStructs;
jrose@665 190 friend class SystemDictionaryHandles;
duke@0 191
duke@0 192 public:
jrose@132 193 enum WKID {
jrose@132 194 NO_WKID = 0,
jrose@132 195
never@2702 196 #define WK_KLASS_ENUM(name, symbol, ignore_o) WK_KLASS_ENUM_NAME(name), WK_KLASS_ENUM_NAME(symbol) = WK_KLASS_ENUM_NAME(name),
jrose@132 197 WK_KLASSES_DO(WK_KLASS_ENUM)
jrose@132 198 #undef WK_KLASS_ENUM
jrose@132 199
jrose@132 200 WKID_LIMIT,
jrose@132 201
jrose@132 202 FIRST_WKID = NO_WKID + 1
jrose@132 203 };
jrose@132 204
jrose@132 205 enum InitOption {
jrose@132 206 Pre, // preloaded; error if not present
twisti@3728 207 Pre_JSR292, // preloaded if EnableInvokeDynamic
jrose@132 208
jrose@132 209 // Order is significant. Options before this point require resolve_or_fail.
jrose@132 210 // Options after this point will use resolve_or_null instead.
jrose@132 211
jrose@132 212 Opt, // preload tried; NULL if not present
jrose@132 213 Opt_Only_JDK14NewRef, // preload tried; use only with NewReflection
jrose@132 214 Opt_Only_JDK15, // preload tried; use only with JDK1.5+
jrose@132 215 OPTION_LIMIT,
jrose@132 216 CEIL_LG_OPTION_LIMIT = 4 // OPTION_LIMIT <= (1<<CEIL_LG_OPTION_LIMIT)
jrose@132 217 };
jrose@132 218
jrose@132 219
duke@0 220 // Returns a class with a given class name and class loader. Loads the
duke@0 221 // class if needed. If not found a NoClassDefFoundError or a
duke@0 222 // ClassNotFoundException is thrown, depending on the value on the
duke@0 223 // throw_error flag. For most uses the throw_error argument should be set
duke@0 224 // to true.
duke@0 225
coleenp@3602 226 static Klass* resolve_or_fail(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS);
duke@0 227 // Convenient call for null loader and protection domain.
coleenp@3602 228 static Klass* resolve_or_fail(Symbol* class_name, bool throw_error, TRAPS);
duke@0 229 private:
duke@0 230 // handle error translation for resolve_or_null results
coleenp@3602 231 static Klass* handle_resolution_exception(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, KlassHandle klass_h, TRAPS);
duke@0 232
duke@0 233 public:
duke@0 234
duke@0 235 // Returns a class with a given class name and class loader.
duke@0 236 // Loads the class if needed. If not found NULL is returned.
coleenp@3602 237 static Klass* resolve_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
duke@0 238 // Version with null loader and protection domain
coleenp@3602 239 static Klass* resolve_or_null(Symbol* class_name, TRAPS);
duke@0 240
duke@0 241 // Resolve a superclass or superinterface. Called from ClassFileParser,
duke@0 242 // parse_interfaces, resolve_instance_class_or_null, load_shared_class
duke@0 243 // "child_name" is the class whose super class or interface is being resolved.
coleenp@3602 244 static Klass* resolve_super_or_fail(Symbol* child_name,
coleenp@2062 245 Symbol* class_name,
duke@0 246 Handle class_loader,
duke@0 247 Handle protection_domain,
duke@0 248 bool is_superclass,
duke@0 249 TRAPS);
duke@0 250
duke@0 251 // Parse new stream. This won't update the system dictionary or
duke@0 252 // class hierarchy, simply parse the stream. Used by JVMTI RedefineClasses.
coleenp@3602 253 static Klass* parse_stream(Symbol* class_name,
duke@0 254 Handle class_loader,
duke@0 255 Handle protection_domain,
duke@0 256 ClassFileStream* st,
jrose@431 257 TRAPS) {
jrose@431 258 KlassHandle nullHandle;
jrose@431 259 return parse_stream(class_name, class_loader, protection_domain, st, nullHandle, NULL, THREAD);
jrose@431 260 }
coleenp@3602 261 static Klass* parse_stream(Symbol* class_name,
jrose@431 262 Handle class_loader,
jrose@431 263 Handle protection_domain,
jrose@431 264 ClassFileStream* st,
jrose@431 265 KlassHandle host_klass,
jrose@431 266 GrowableArray<Handle>* cp_patches,
duke@0 267 TRAPS);
duke@0 268
duke@0 269 // Resolve from stream (called by jni_DefineClass and JVM_DefineClass)
coleenp@3602 270 static Klass* resolve_from_stream(Symbol* class_name, Handle class_loader,
acorn@973 271 Handle protection_domain,
acorn@973 272 ClassFileStream* st, bool verify, TRAPS);
duke@0 273
duke@0 274 // Lookup an already loaded class. If not found NULL is returned.
coleenp@3602 275 static Klass* find(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
duke@0 276
duke@0 277 // Lookup an already loaded instance or array class.
duke@0 278 // Do not make any queries to class loaders; consult only the cache.
duke@0 279 // If not found NULL is returned.
coleenp@3602 280 static Klass* find_instance_or_array_klass(Symbol* class_name,
duke@0 281 Handle class_loader,
duke@0 282 Handle protection_domain,
duke@0 283 TRAPS);
duke@0 284
duke@0 285 // Lookup an instance or array class that has already been loaded
duke@0 286 // either into the given class loader, or else into another class
duke@0 287 // loader that is constrained (via loader constraints) to produce
duke@0 288 // a consistent class. Do not take protection domains into account.
duke@0 289 // Do not make any queries to class loaders; consult only the cache.
duke@0 290 // Return NULL if the class is not found.
duke@0 291 //
duke@0 292 // This function is a strict superset of find_instance_or_array_klass.
duke@0 293 // This function (the unchecked version) makes a conservative prediction
duke@0 294 // of the result of the checked version, assuming successful lookup.
duke@0 295 // If both functions return non-null, they must return the same value.
duke@0 296 // Also, the unchecked version may sometimes be non-null where the
duke@0 297 // checked version is null. This can occur in several ways:
duke@0 298 // 1. No query has yet been made to the class loader.
duke@0 299 // 2. The class loader was queried, but chose not to delegate.
duke@0 300 // 3. ClassLoader.checkPackageAccess rejected a proposed protection domain.
duke@0 301 // 4. Loading was attempted, but there was a linkage error of some sort.
duke@0 302 // In all of these cases, the loader constraints on this type are
duke@0 303 // satisfied, and it is safe for classes in the given class loader
duke@0 304 // to manipulate strongly-typed values of the found class, subject
duke@0 305 // to local linkage and access checks.
coleenp@3602 306 static Klass* find_constrained_instance_or_array_klass(Symbol* class_name,
duke@0 307 Handle class_loader,
duke@0 308 TRAPS);
duke@0 309
duke@0 310 // Iterate over all klasses in dictionary
duke@0 311 // Just the classes from defining class loaders
coleenp@3602 312 static void classes_do(void f(Klass*));
duke@0 313 // Added for initialize_itable_for_klass to handle exceptions
coleenp@3602 314 static void classes_do(void f(Klass*, TRAPS), TRAPS);
duke@0 315 // All classes, and their class loaders
coleenp@3602 316 static void classes_do(void f(Klass*, ClassLoaderData*));
coleenp@4665 317
coleenp@3602 318 static void placeholders_do(void f(Symbol*));
duke@0 319
duke@0 320 // Iterate over all methods in all klasses in dictionary
coleenp@3602 321 static void methods_do(void f(Method*));
duke@0 322
duke@0 323 // Garbage collection support
duke@0 324
duke@0 325 // This method applies "blk->do_oop" to all the pointers to "system"
duke@0 326 // classes and loaders.
duke@0 327 static void always_strong_oops_do(OopClosure* blk);
coleenp@3602 328 static void always_strong_classes_do(KlassClosure* closure);
duke@0 329
duke@0 330 // Unload (that is, break root links to) all unmarked classes and
duke@0 331 // loaders. Returns "true" iff something was unloaded.
duke@0 332 static bool do_unloading(BoolObjectClosure* is_alive);
duke@0 333
acorn@3056 334 static int calculate_systemdictionary_size(int loadedclasses);
acorn@3056 335
duke@0 336 // Applies "f->do_oop" to all root oops in the system dictionary.
duke@0 337 static void oops_do(OopClosure* f);
stefank@6465 338 static void roots_oops_do(OopClosure* strong, OopClosure* weak);
duke@0 339
duke@0 340 // System loader lock
duke@0 341 static oop system_loader_lock() { return _system_loader_lock_obj; }
duke@0 342
duke@0 343 private:
coleenp@3602 344 // Extended Redefine classes support (tbi)
coleenp@3602 345 static void preloaded_classes_do(KlassClosure* f);
coleenp@3602 346 static void lazily_loaded_classes_do(KlassClosure* f);
duke@0 347 public:
duke@0 348 // Sharing support.
duke@0 349 static void reorder_dictionary();
duke@0 350 static void copy_buckets(char** top, char* end);
duke@0 351 static void copy_table(char** top, char* end);
duke@0 352 static void reverse();
zgu@3465 353 static void set_shared_dictionary(HashtableBucket<mtClass>* t, int length,
duke@0 354 int number_of_entries);
duke@0 355 // Printing
duke@0 356 static void print() PRODUCT_RETURN;
duke@0 357 static void print_class_statistics() PRODUCT_RETURN;
duke@0 358 static void print_method_statistics() PRODUCT_RETURN;
duke@0 359
duke@0 360 // Number of contained klasses
duke@0 361 // This is both fully loaded classes and classes in the process
duke@0 362 // of being loaded
duke@0 363 static int number_of_classes();
duke@0 364
duke@0 365 // Monotonically increasing counter which grows as classes are
duke@0 366 // loaded or modifications such as hot-swapping or setting/removing
duke@0 367 // of breakpoints are performed
duke@0 368 static inline int number_of_modifications() { assert_locked_or_safepoint(Compile_lock); return _number_of_modifications; }
duke@0 369 // Needed by evolution and breakpoint code
duke@0 370 static inline void notice_modification() { assert_locked_or_safepoint(Compile_lock); ++_number_of_modifications; }
duke@0 371
duke@0 372 // Verification
duke@0 373 static void verify();
duke@0 374
duke@0 375 #ifdef ASSERT
coleenp@2062 376 static bool is_internal_format(Symbol* class_name);
duke@0 377 #endif
duke@0 378
duke@0 379 // Initialization
duke@0 380 static void initialize(TRAPS);
duke@0 381
duke@0 382 // Fast access to commonly used classes (preloaded)
coleenp@3602 383 static Klass* check_klass(Klass* k) {
duke@0 384 assert(k != NULL, "preloaded klass not initialized");
duke@0 385 return k;
duke@0 386 }
duke@0 387
twisti@3723 388 static Klass* check_klass_Pre( Klass* k) { return check_klass(k); }
twisti@3728 389 static Klass* check_klass_Pre_JSR292(Klass* k) { return EnableInvokeDynamic ? check_klass(k) : k; }
twisti@3723 390 static Klass* check_klass_Opt( Klass* k) { return k; }
coleenp@3602 391 static Klass* check_klass_Opt_Only_JDK15(Klass* k) {
jrose@132 392 assert(JDK_Version::is_gte_jdk15x_version(), "JDK 1.5 only");
jrose@132 393 return k;
jrose@132 394 }
coleenp@3602 395 static Klass* check_klass_Opt_Only_JDK14NewRef(Klass* k) {
duke@0 396 assert(JDK_Version::is_gte_jdk14x_version() && UseNewReflection, "JDK 1.4 only");
jrose@132 397 // despite the optional loading, if you use this it must be present:
jrose@132 398 return check_klass(k);
duke@0 399 }
duke@0 400
jrose@132 401 static bool initialize_wk_klass(WKID id, int init_opt, TRAPS);
jrose@132 402 static void initialize_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS);
jrose@132 403 static void initialize_wk_klasses_through(WKID end_id, WKID &start_id, TRAPS) {
jrose@132 404 int limit = (int)end_id + 1;
jrose@132 405 initialize_wk_klasses_until((WKID) limit, start_id, THREAD);
jrose@132 406 }
duke@0 407
jrose@132 408 public:
never@2702 409 #define WK_KLASS_DECLARE(name, symbol, option) \
coleenp@3602 410 static Klass* name() { return check_klass_##option(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); } \
coleenp@3602 411 static Klass** name##_addr() { \
coleenp@3602 412 return &SystemDictionary::_well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]; \
coleenp@3602 413 }
jrose@132 414 WK_KLASSES_DO(WK_KLASS_DECLARE);
jrose@132 415 #undef WK_KLASS_DECLARE
duke@0 416
coleenp@3602 417 static Klass* well_known_klass(WKID id) {
never@2702 418 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
never@2702 419 return _well_known_klasses[id];
never@2702 420 }
never@2702 421
coleenp@3602 422 static Klass** well_known_klass_addr(WKID id) {
coleenp@3602 423 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
coleenp@3602 424 return &_well_known_klasses[id];
coleenp@3602 425 }
coleenp@3602 426
jrose@132 427 // Local definition for direct access to the private array:
jrose@147 428 #define WK_KLASS(name) _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]
duke@0 429
coleenp@3602 430 static Klass* box_klass(BasicType t) {
duke@0 431 assert((uint)t < T_VOID+1, "range check");
duke@0 432 return check_klass(_box_klasses[t]);
duke@0 433 }
coleenp@3602 434 static BasicType box_klass_type(Klass* k); // inverse of box_klass
duke@0 435
duke@0 436 // methods returning lazily loaded klasses
duke@0 437 // The corresponding method to load the class must be called before calling them.
coleenp@3602 438 static Klass* abstract_ownable_synchronizer_klass() { return check_klass(_abstract_ownable_synchronizer_klass); }
duke@0 439
duke@0 440 static void load_abstract_ownable_synchronizer_klass(TRAPS);
duke@0 441
duke@0 442 private:
duke@0 443 // Tells whether ClassLoader.loadClassInternal is present
duke@0 444 static bool has_loadClassInternal() { return _has_loadClassInternal; }
duke@0 445
coleenp@3602 446 // Returns the class loader data to be used when looking up/updating the
coleenp@3602 447 // system dictionary.
coleenp@3602 448 static ClassLoaderData *class_loader_data(Handle class_loader) {
coleenp@3602 449 return ClassLoaderData::class_loader_data(class_loader());
coleenp@3602 450 }
coleenp@3602 451
duke@0 452 public:
duke@0 453 // Tells whether ClassLoader.checkPackageAccess is present
duke@0 454 static bool has_checkPackageAccess() { return _has_checkPackageAccess; }
duke@0 455
coleenp@3963 456 static bool Parameter_klass_loaded() { return WK_KLASS(reflect_Parameter_klass) != NULL; }
never@1142 457 static bool Class_klass_loaded() { return WK_KLASS(Class_klass) != NULL; }
never@1142 458 static bool Cloneable_klass_loaded() { return WK_KLASS(Cloneable_klass) != NULL; }
coleenp@3602 459 static bool Object_klass_loaded() { return WK_KLASS(Object_klass) != NULL; }
coleenp@3602 460 static bool ClassLoader_klass_loaded() { return WK_KLASS(ClassLoader_klass) != NULL; }
duke@0 461
duke@0 462 // Returns default system loader
duke@0 463 static oop java_system_loader();
duke@0 464
duke@0 465 // Compute the default system loader
duke@0 466 static void compute_java_system_loader(TRAPS);
duke@0 467
coleenp@3602 468 // Register a new class loader
coleenp@3869 469 static ClassLoaderData* register_loader(Handle class_loader, TRAPS);
duke@0 470 private:
duke@0 471 // Mirrors for primitive classes (created eagerly)
duke@0 472 static oop check_mirror(oop m) {
duke@0 473 assert(m != NULL, "mirror not initialized");
duke@0 474 return m;
duke@0 475 }
duke@0 476
duke@0 477 public:
duke@0 478 // Note: java_lang_Class::primitive_type is the inverse of java_mirror
duke@0 479
duke@0 480 // Check class loader constraints
coleenp@2062 481 static bool add_loader_constraint(Symbol* name, Handle loader1,
duke@0 482 Handle loader2, TRAPS);
acorn@4405 483 static Symbol* check_signature_loaders(Symbol* signature, Handle loader1,
acorn@4405 484 Handle loader2, bool is_method, TRAPS);
duke@0 485
jrose@710 486 // JSR 292
twisti@3534 487 // find a java.lang.invoke.MethodHandle.invoke* method for a given signature
twisti@3534 488 // (asks Java to compute it if necessary, except in a compiler thread)
twisti@3534 489 static methodHandle find_method_handle_invoker(Symbol* name,
twisti@3534 490 Symbol* signature,
twisti@3534 491 KlassHandle accessing_klass,
twisti@3534 492 Handle *appendix_result,
twisti@3698 493 Handle *method_type_result,
twisti@3534 494 TRAPS);
twisti@3534 495 // for a given signature, find the internal MethodHandle method (linkTo* or invokeBasic)
twisti@3534 496 // (does not ask Java, since this is a low-level intrinsic defined by the JVM)
twisti@3534 497 static methodHandle find_method_handle_intrinsic(vmIntrinsics::ID iid,
twisti@3534 498 Symbol* signature,
twisti@3534 499 TRAPS);
twisti@3534 500 // find a java.lang.invoke.MethodType object for a given signature
twisti@3534 501 // (asks Java to compute it if necessary, except in a compiler thread)
coleenp@2062 502 static Handle find_method_handle_type(Symbol* signature,
jrose@1428 503 KlassHandle accessing_klass,
jrose@1427 504 TRAPS);
twisti@3534 505
jrose@2204 506 // ask Java to compute a java.lang.invoke.MethodHandle object for a given CP entry
jrose@1522 507 static Handle link_method_handle_constant(KlassHandle caller,
jrose@1522 508 int ref_kind, //e.g., JVM_REF_invokeVirtual
jrose@1522 509 KlassHandle callee,
coleenp@2062 510 Symbol* name,
coleenp@2062 511 Symbol* signature,
jrose@1522 512 TRAPS);
twisti@3534 513
jrose@726 514 // ask Java to create a dynamic call site, while linking an invokedynamic op
twisti@3534 515 static methodHandle find_dynamic_call_site_invoker(KlassHandle caller,
twisti@3534 516 Handle bootstrap_method,
twisti@3534 517 Symbol* name,
twisti@3534 518 Symbol* type,
twisti@3534 519 Handle *appendix_result,
twisti@3698 520 Handle *method_type_result,
twisti@3534 521 TRAPS);
jrose@726 522
duke@0 523 // Utility for printing loader "name" as part of tracing constraints
duke@0 524 static const char* loader_name(oop loader) {
duke@0 525 return ((loader) == NULL ? "<bootloader>" :
coleenp@3602 526 InstanceKlass::cast((loader)->klass())->name()->as_C_string() );
coleenp@3602 527 }
coleenp@3602 528 static const char* loader_name(ClassLoaderData* loader_data) {
coleenp@3869 529 return (loader_data->class_loader() == NULL ? "<bootloader>" :
coleenp@3602 530 InstanceKlass::cast((loader_data->class_loader())->klass())->name()->as_C_string() );
duke@0 531 }
duke@0 532
duke@0 533 // Record the error when the first attempt to resolve a reference from a constant
duke@0 534 // pool entry to a class fails.
coleenp@2062 535 static void add_resolution_error(constantPoolHandle pool, int which, Symbol* error);
coleenp@3602 536 static void delete_resolution_error(ConstantPool* pool);
coleenp@2062 537 static Symbol* find_resolution_error(constantPoolHandle pool, int which);
duke@0 538
duke@0 539 private:
duke@0 540
duke@0 541 enum Constants {
duke@0 542 _loader_constraint_size = 107, // number of entries in constraint table
duke@0 543 _resolution_error_size = 107, // number of entries in resolution error table
jrose@710 544 _invoke_method_size = 139, // number of entries in invoke method table
acorn@3056 545 _nof_buckets = 1009, // number of buckets in hash table for placeholders
acorn@3056 546 _old_default_sdsize = 1009, // backward compat for system dictionary size
acorn@3056 547 _prime_array_size = 8, // array of primes for system dictionary size
acorn@3056 548 _average_depth_goal = 3 // goal for lookup length
duke@0 549 };
duke@0 550
duke@0 551
duke@0 552 // Static variables
duke@0 553
acorn@3056 554 // hashtable sizes for system dictionary to allow growth
acorn@3056 555 // prime numbers for system dictionary size
acorn@3056 556 static int _sdgeneration;
acorn@3056 557 static const int _primelist[_prime_array_size];
acorn@3056 558
duke@0 559 // Hashtable holding loaded classes.
duke@0 560 static Dictionary* _dictionary;
duke@0 561
duke@0 562 // Hashtable holding placeholders for classes being loaded.
duke@0 563 static PlaceholderTable* _placeholders;
duke@0 564
duke@0 565 // Hashtable holding classes from the shared archive.
duke@0 566 static Dictionary* _shared_dictionary;
duke@0 567
duke@0 568 // Monotonically increasing counter which grows with
duke@0 569 // _number_of_classes as well as hot-swapping and breakpoint setting
duke@0 570 // and removal.
duke@0 571 static int _number_of_modifications;
duke@0 572
duke@0 573 // Lock object for system class loader
duke@0 574 static oop _system_loader_lock_obj;
duke@0 575
duke@0 576 // Constraints on class loaders
duke@0 577 static LoaderConstraintTable* _loader_constraints;
duke@0 578
duke@0 579 // Resolution errors
duke@0 580 static ResolutionErrorTable* _resolution_errors;
duke@0 581
jrose@710 582 // Invoke methods (JSR 292)
jrose@710 583 static SymbolPropertyTable* _invoke_method_table;
jrose@710 584
duke@0 585 public:
duke@0 586 // for VM_CounterDecay iteration support
duke@0 587 friend class CounterDecay;
coleenp@3602 588 static Klass* try_get_next_class();
duke@0 589
duke@0 590 private:
duke@0 591 static void validate_protection_domain(instanceKlassHandle klass,
duke@0 592 Handle class_loader,
duke@0 593 Handle protection_domain, TRAPS);
duke@0 594
duke@0 595 friend class VM_PopulateDumpSharedSpace;
duke@0 596 friend class TraversePlaceholdersClosure;
duke@0 597 static Dictionary* dictionary() { return _dictionary; }
duke@0 598 static Dictionary* shared_dictionary() { return _shared_dictionary; }
duke@0 599 static PlaceholderTable* placeholders() { return _placeholders; }
duke@0 600 static LoaderConstraintTable* constraints() { return _loader_constraints; }
duke@0 601 static ResolutionErrorTable* resolution_errors() { return _resolution_errors; }
jrose@710 602 static SymbolPropertyTable* invoke_method_table() { return _invoke_method_table; }
duke@0 603
duke@0 604 // Basic loading operations
coleenp@3602 605 static Klass* resolve_instance_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
coleenp@3602 606 static Klass* resolve_array_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
coleenp@2062 607 static instanceKlassHandle handle_parallel_super_load(Symbol* class_name, Symbol* supername, Handle class_loader, Handle protection_domain, Handle lockObject, TRAPS);
duke@0 608 // Wait on SystemDictionary_lock; unlocks lockObject before
duke@0 609 // waiting; relocks lockObject with correct recursion count
duke@0 610 // after waiting, but before reentering SystemDictionary_lock
duke@0 611 // to preserve lock order semantics.
duke@0 612 static void double_lock_wait(Handle lockObject, TRAPS);
duke@0 613 static void define_instance_class(instanceKlassHandle k, TRAPS);
coleenp@2062 614 static instanceKlassHandle find_or_define_instance_class(Symbol* class_name,
duke@0 615 Handle class_loader,
duke@0 616 instanceKlassHandle k, TRAPS);
coleenp@2062 617 static instanceKlassHandle load_shared_class(Symbol* class_name,
duke@0 618 Handle class_loader, TRAPS);
duke@0 619 static instanceKlassHandle load_shared_class(instanceKlassHandle ik,
duke@0 620 Handle class_loader, TRAPS);
coleenp@2062 621 static instanceKlassHandle load_instance_class(Symbol* class_name, Handle class_loader, TRAPS);
duke@0 622 static Handle compute_loader_lock_object(Handle class_loader, TRAPS);
duke@0 623 static void check_loader_lock_contention(Handle loader_lock, TRAPS);
acorn@514 624 static bool is_parallelCapable(Handle class_loader);
acorn@1075 625 static bool is_parallelDefine(Handle class_loader);
duke@0 626
twisti@4431 627 public:
twisti@4431 628 static bool is_ext_class_loader(Handle class_loader);
twisti@4431 629
twisti@4431 630 private:
coleenp@3602 631 static Klass* find_shared_class(Symbol* class_name);
duke@0 632
duke@0 633 // Setup link to hierarchy
duke@0 634 static void add_to_hierarchy(instanceKlassHandle k, TRAPS);
duke@0 635
sla@4802 636 // event based tracing
mgronlun@5696 637 static void post_class_load_event(const Ticks& start_time, instanceKlassHandle k,
sla@4802 638 Handle initiating_loader);
duke@0 639 // We pass in the hashtable index so we can calculate it outside of
duke@0 640 // the SystemDictionary_lock.
duke@0 641
duke@0 642 // Basic find on loaded classes
coleenp@3602 643 static Klass* find_class(int index, unsigned int hash,
coleenp@3602 644 Symbol* name, ClassLoaderData* loader_data);
coleenp@3602 645 static Klass* find_class(Symbol* class_name, ClassLoaderData* loader_data);
duke@0 646
duke@0 647 // Basic find on classes in the midst of being loaded
coleenp@3602 648 static Symbol* find_placeholder(Symbol* name, ClassLoaderData* loader_data);
duke@0 649
duke@0 650 // Updating entry in dictionary
duke@0 651 // Add a completely loaded class
coleenp@2062 652 static void add_klass(int index, Symbol* class_name,
coleenp@3602 653 ClassLoaderData* loader_data, KlassHandle obj);
duke@0 654
duke@0 655 // Add a placeholder for a class being loaded
duke@0 656 static void add_placeholder(int index,
coleenp@2062 657 Symbol* class_name,
coleenp@3602 658 ClassLoaderData* loader_data);
duke@0 659 static void remove_placeholder(int index,
coleenp@2062 660 Symbol* class_name,
coleenp@3602 661 ClassLoaderData* loader_data);
duke@0 662
duke@0 663 // Performs cleanups after resolve_super_or_fail. This typically needs
duke@0 664 // to be called on failure.
duke@0 665 // Won't throw, but can block.
coleenp@2062 666 static void resolution_cleanups(Symbol* class_name,
coleenp@3602 667 ClassLoaderData* loader_data,
duke@0 668 TRAPS);
duke@0 669
duke@0 670 // Initialization
duke@0 671 static void initialize_preloaded_classes(TRAPS);
duke@0 672
duke@0 673 // Class loader constraints
duke@0 674 static void check_constraints(int index, unsigned int hash,
duke@0 675 instanceKlassHandle k, Handle loader,
duke@0 676 bool defining, TRAPS);
duke@0 677 static void update_dictionary(int d_index, unsigned int d_hash,
duke@0 678 int p_index, unsigned int p_hash,
coleenp@3602 679 instanceKlassHandle k, Handle loader,
coleenp@3602 680 TRAPS);
duke@0 681
duke@0 682 // Variables holding commonly used klasses (preloaded)
coleenp@3602 683 static Klass* _well_known_klasses[];
duke@0 684
duke@0 685 // Lazily loaded klasses
coleenp@3602 686 static Klass* volatile _abstract_ownable_synchronizer_klass;
duke@0 687
jrose@132 688 // table of box klasses (int_klass, etc.)
coleenp@3602 689 static Klass* _box_klasses[T_VOID+1];
duke@0 690
duke@0 691 static oop _java_system_loader;
duke@0 692
duke@0 693 static bool _has_loadClassInternal;
duke@0 694 static bool _has_checkPackageAccess;
duke@0 695 };
jrose@665 696
stefank@1879 697 #endif // SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP