1 /*
2 * Copyright (c) 1997, 2019, 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,
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23 */
24
25 #ifndef SHARE_CLASSFILE_SYSTEMDICTIONARY_HPP
26 #define SHARE_CLASSFILE_SYSTEMDICTIONARY_HPP
27
28 #include "classfile/classLoaderData.hpp"
29 #include "oops/objArrayOop.hpp"
30 #include "oops/symbol.hpp"
31 #include "runtime/java.hpp"
32 #include "runtime/mutexLocker.hpp"
33 #include "runtime/reflectionUtils.hpp"
34 #include "runtime/signature.hpp"
35 #include "utilities/hashtable.hpp"
36
37 // The dictionary in each ClassLoaderData stores all loaded classes, either
38 // initiatied by its class loader or defined by its class loader:
39 //
40 // class loader -> ClassLoaderData -> [class, protection domain set]
41 //
42 // Classes are loaded lazily. The default VM class loader is
43 // represented as NULL.
44
45 // The underlying data structure is an open hash table (Dictionary) per
46 // ClassLoaderData with a fixed number of buckets. During loading the
47 // class loader object is locked, (for the VM loader a private lock object is used).
48 // The global SystemDictionary_lock is held for all additions into the ClassLoaderData
49 // dictionaries. TODO: fix lock granularity so that class loading can
50 // be done concurrently, but only by different loaders.
51 //
52 // During loading a placeholder (name, loader) is temporarily placed in
53 // a side data structure, and is used to detect ClassCircularityErrors
54 // and to perform verification during GC. A GC can occur in the midst
55 // of class loading, as we call out to Java, have to take locks, etc.
56 //
57 // When class loading is finished, a new entry is added to the dictionary
58 // of the class loader and the placeholder is removed. Note that the protection
59 // domain field of the dictionary entry has not yet been filled in when
60 // the "real" dictionary entry is created.
61 //
62 // Clients of this class who are interested in finding if a class has
63 // been completely loaded -- not classes in the process of being loaded --
64 // can read the dictionary unlocked. This is safe because
65 // - entries are only deleted at safepoints
66 // - readers cannot come to a safepoint while actively examining
67 // an entry (an entry cannot be deleted from under a reader)
68 // - entries must be fully formed before they are available to concurrent
69 // readers (we must ensure write ordering)
70 //
71 // Note that placeholders are deleted at any time, as they are removed
72 // when a class is completely loaded. Therefore, readers as well as writers
73 // of placeholders must hold the SystemDictionary_lock.
74 //
75
76 class BootstrapInfo;
77 class ClassFileStream;
78 class Dictionary;
79 class PlaceholderTable;
80 class LoaderConstraintTable;
81 template <MEMFLAGS F> class HashtableBucket;
82 class ResolutionErrorTable;
83 class SymbolPropertyTable;
84 class ProtectionDomainCacheTable;
85 class ProtectionDomainCacheEntry;
86 class GCTimer;
87
88 #define WK_KLASS_ENUM_NAME(kname) kname##_knum
89
90 // Certain classes, such as java.lang.Object and java.lang.String,
91 // are "well-known", in the sense that no class loader is allowed
92 // to provide a different definition.
93 //
94 // Each well-known class has a short klass name (like object_klass),
95 // and a vmSymbol name (like java_lang_Object).
96 //
97 // The order of these definitions is significant: the classes are
98 // resolved during early VM start-up by resolve_well_known_classes
99 // in this order. Changing the order may require careful restructuring
100 // of the VM start-up sequence.
101 //
102 #define WK_KLASSES_DO(do_klass) \
103 /* well-known classes */ \
104 do_klass(Object_klass, java_lang_Object ) \
105 do_klass(String_klass, java_lang_String ) \
106 do_klass(Class_klass, java_lang_Class ) \
107 do_klass(Cloneable_klass, java_lang_Cloneable ) \
108 do_klass(ClassLoader_klass, java_lang_ClassLoader ) \
109 do_klass(Serializable_klass, java_io_Serializable ) \
110 do_klass(System_klass, java_lang_System ) \
111 do_klass(Throwable_klass, java_lang_Throwable ) \
112 do_klass(Error_klass, java_lang_Error ) \
113 do_klass(ThreadDeath_klass, java_lang_ThreadDeath ) \
114 do_klass(Exception_klass, java_lang_Exception ) \
115 do_klass(RuntimeException_klass, java_lang_RuntimeException ) \
116 do_klass(SecurityManager_klass, java_lang_SecurityManager ) \
117 do_klass(ProtectionDomain_klass, java_security_ProtectionDomain ) \
118 do_klass(AccessControlContext_klass, java_security_AccessControlContext ) \
119 do_klass(AccessController_klass, java_security_AccessController ) \
120 do_klass(SecureClassLoader_klass, java_security_SecureClassLoader ) \
121 do_klass(ClassNotFoundException_klass, java_lang_ClassNotFoundException ) \
122 do_klass(NoClassDefFoundError_klass, java_lang_NoClassDefFoundError ) \
123 do_klass(LinkageError_klass, java_lang_LinkageError ) \
124 do_klass(ClassCastException_klass, java_lang_ClassCastException ) \
125 do_klass(ArrayStoreException_klass, java_lang_ArrayStoreException ) \
126 do_klass(VirtualMachineError_klass, java_lang_VirtualMachineError ) \
127 do_klass(OutOfMemoryError_klass, java_lang_OutOfMemoryError ) \
128 do_klass(StackOverflowError_klass, java_lang_StackOverflowError ) \
129 do_klass(IllegalMonitorStateException_klass, java_lang_IllegalMonitorStateException ) \
130 do_klass(Reference_klass, java_lang_ref_Reference ) \
131 \
132 /* ref klasses and set reference types */ \
133 do_klass(SoftReference_klass, java_lang_ref_SoftReference ) \
134 do_klass(WeakReference_klass, java_lang_ref_WeakReference ) \
135 do_klass(FinalReference_klass, java_lang_ref_FinalReference ) \
136 do_klass(PhantomReference_klass, java_lang_ref_PhantomReference ) \
137 do_klass(Finalizer_klass, java_lang_ref_Finalizer ) \
138 \
139 do_klass(Thread_klass, java_lang_Thread ) \
140 do_klass(ThreadGroup_klass, java_lang_ThreadGroup ) \
141 do_klass(Properties_klass, java_util_Properties ) \
142 do_klass(Module_klass, java_lang_Module ) \
143 do_klass(reflect_AccessibleObject_klass, java_lang_reflect_AccessibleObject ) \
144 do_klass(reflect_Field_klass, java_lang_reflect_Field ) \
145 do_klass(reflect_Parameter_klass, java_lang_reflect_Parameter ) \
146 do_klass(reflect_Method_klass, java_lang_reflect_Method ) \
147 do_klass(reflect_Constructor_klass, java_lang_reflect_Constructor ) \
148 \
149 /* NOTE: needed too early in bootstrapping process to have checks based on JDK version */ \
150 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \
151 do_klass(reflect_MagicAccessorImpl_klass, reflect_MagicAccessorImpl ) \
152 do_klass(reflect_MethodAccessorImpl_klass, reflect_MethodAccessorImpl ) \
153 do_klass(reflect_ConstructorAccessorImpl_klass, reflect_ConstructorAccessorImpl ) \
154 do_klass(reflect_DelegatingClassLoader_klass, reflect_DelegatingClassLoader ) \
155 do_klass(reflect_ConstantPool_klass, reflect_ConstantPool ) \
156 do_klass(reflect_UnsafeStaticFieldAccessorImpl_klass, reflect_UnsafeStaticFieldAccessorImpl ) \
157 do_klass(reflect_CallerSensitive_klass, reflect_CallerSensitive ) \
158 \
159 /* support for dynamic typing; it's OK if these are NULL in earlier JDKs */ \
160 do_klass(DirectMethodHandle_klass, java_lang_invoke_DirectMethodHandle ) \
161 do_klass(MethodHandle_klass, java_lang_invoke_MethodHandle ) \
162 do_klass(VarHandle_klass, java_lang_invoke_VarHandle ) \
163 do_klass(MemberName_klass, java_lang_invoke_MemberName ) \
164 do_klass(ResolvedMethodName_klass, java_lang_invoke_ResolvedMethodName ) \
165 do_klass(MethodHandleNatives_klass, java_lang_invoke_MethodHandleNatives ) \
166 do_klass(LambdaForm_klass, java_lang_invoke_LambdaForm ) \
167 do_klass(MethodType_klass, java_lang_invoke_MethodType ) \
168 do_klass(BootstrapMethodError_klass, java_lang_BootstrapMethodError ) \
169 do_klass(CallSite_klass, java_lang_invoke_CallSite ) \
170 do_klass(Context_klass, java_lang_invoke_MethodHandleNatives_CallSiteContext ) \
171 do_klass(ConstantCallSite_klass, java_lang_invoke_ConstantCallSite ) \
172 do_klass(MutableCallSite_klass, java_lang_invoke_MutableCallSite ) \
173 do_klass(VolatileCallSite_klass, java_lang_invoke_VolatileCallSite ) \
174 /* Note: MethodHandle must be first, and VolatileCallSite last in group */ \
175 \
176 do_klass(AssertionStatusDirectives_klass, java_lang_AssertionStatusDirectives ) \
177 do_klass(StringBuffer_klass, java_lang_StringBuffer ) \
178 do_klass(StringBuilder_klass, java_lang_StringBuilder ) \
179 do_klass(UnsafeConstants_klass, jdk_internal_misc_UnsafeConstants ) \
180 do_klass(internal_Unsafe_klass, jdk_internal_misc_Unsafe ) \
181 do_klass(module_Modules_klass, jdk_internal_module_Modules ) \
182 \
183 /* support for CDS */ \
184 do_klass(ByteArrayInputStream_klass, java_io_ByteArrayInputStream ) \
185 do_klass(URL_klass, java_net_URL ) \
186 do_klass(Jar_Manifest_klass, java_util_jar_Manifest ) \
187 do_klass(jdk_internal_loader_ClassLoaders_klass, jdk_internal_loader_ClassLoaders ) \
188 do_klass(jdk_internal_loader_ClassLoaders_AppClassLoader_klass, jdk_internal_loader_ClassLoaders_AppClassLoader) \
189 do_klass(jdk_internal_loader_ClassLoaders_PlatformClassLoader_klass, jdk_internal_loader_ClassLoaders_PlatformClassLoader) \
190 do_klass(CodeSource_klass, java_security_CodeSource ) \
191 \
192 do_klass(StackTraceElement_klass, java_lang_StackTraceElement ) \
193 \
194 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \
195 do_klass(nio_Buffer_klass, java_nio_Buffer ) \
196 \
197 /* Stack Walking */ \
198 do_klass(StackWalker_klass, java_lang_StackWalker ) \
199 do_klass(AbstractStackWalker_klass, java_lang_StackStreamFactory_AbstractStackWalker ) \
200 do_klass(StackFrameInfo_klass, java_lang_StackFrameInfo ) \
201 do_klass(LiveStackFrameInfo_klass, java_lang_LiveStackFrameInfo ) \
202 \
203 /* support for stack dump lock analysis */ \
204 do_klass(java_util_concurrent_locks_AbstractOwnableSynchronizer_klass, java_util_concurrent_locks_AbstractOwnableSynchronizer) \
205 \
206 /* boxing klasses */ \
207 do_klass(Boolean_klass, java_lang_Boolean ) \
208 do_klass(Character_klass, java_lang_Character ) \
209 do_klass(Float_klass, java_lang_Float ) \
210 do_klass(Double_klass, java_lang_Double ) \
211 do_klass(Byte_klass, java_lang_Byte ) \
212 do_klass(Short_klass, java_lang_Short ) \
213 do_klass(Integer_klass, java_lang_Integer ) \
214 do_klass(Long_klass, java_lang_Long ) \
215 \
216 /* force inline of iterators */ \
217 do_klass(Iterator_klass, java_util_Iterator ) \
218 \
219 /*end*/
220
221 class SystemDictionary : AllStatic {
222 friend class BootstrapInfo;
223 friend class VMStructs;
224 friend class SystemDictionaryHandles;
225
226 public:
227 enum WKID {
228 NO_WKID = 0,
229
230 #define WK_KLASS_ENUM(name, symbol) WK_KLASS_ENUM_NAME(name), WK_KLASS_ENUM_NAME(symbol) = WK_KLASS_ENUM_NAME(name),
231 WK_KLASSES_DO(WK_KLASS_ENUM)
232 #undef WK_KLASS_ENUM
233
234 WKID_LIMIT,
235
236 FIRST_WKID = NO_WKID + 1
237 };
238
239 // Returns a class with a given class name and class loader. Loads the
240 // class if needed. If not found a NoClassDefFoundError or a
241 // ClassNotFoundException is thrown, depending on the value on the
242 // throw_error flag. For most uses the throw_error argument should be set
243 // to true.
244
245 static Klass* resolve_or_fail(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS);
246 // Convenient call for null loader and protection domain.
247 static Klass* resolve_or_fail(Symbol* class_name, bool throw_error, TRAPS);
248 protected:
249 // handle error translation for resolve_or_null results
250 static Klass* handle_resolution_exception(Symbol* class_name, bool throw_error, Klass* klass, TRAPS);
251
252 public:
253
254 // Returns a class with a given class name and class loader.
255 // Loads the class if needed. If not found NULL is returned.
256 static Klass* resolve_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
257 // Version with null loader and protection domain
258 static Klass* resolve_or_null(Symbol* class_name, TRAPS);
259
260 // Resolve a superclass or superinterface. Called from ClassFileParser,
261 // parse_interfaces, resolve_instance_class_or_null, load_shared_class
262 // "child_name" is the class whose super class or interface is being resolved.
263 static InstanceKlass* resolve_super_or_fail(Symbol* child_name,
264 Symbol* class_name,
265 Handle class_loader,
266 Handle protection_domain,
267 bool is_superclass,
268 TRAPS);
269
270 // Parse new stream. This won't update the dictionary or
271 // class hierarchy, simply parse the stream. Used by JVMTI RedefineClasses.
272 // Also used by Unsafe_DefineAnonymousClass
273 static InstanceKlass* parse_stream(Symbol* class_name,
274 Handle class_loader,
275 Handle protection_domain,
276 ClassFileStream* st,
277 TRAPS) {
278 return parse_stream(class_name,
279 class_loader,
280 protection_domain,
281 st,
282 NULL, // unsafe_anonymous_host
283 NULL, // cp_patches
284 THREAD);
285 }
286 static InstanceKlass* parse_stream(Symbol* class_name,
287 Handle class_loader,
288 Handle protection_domain,
289 ClassFileStream* st,
290 const InstanceKlass* unsafe_anonymous_host,
291 GrowableArray<Handle>* cp_patches,
292 TRAPS);
293
294 // Resolve from stream (called by jni_DefineClass and JVM_DefineClass)
295 static InstanceKlass* resolve_from_stream(Symbol* class_name,
296 Handle class_loader,
297 Handle protection_domain,
298 ClassFileStream* st,
299 TRAPS);
300
301 // Lookup an already loaded class. If not found NULL is returned.
302 static Klass* find(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
303
304 // Lookup an already loaded instance or array class.
305 // Do not make any queries to class loaders; consult only the cache.
306 // If not found NULL is returned.
307 static Klass* find_instance_or_array_klass(Symbol* class_name,
308 Handle class_loader,
309 Handle protection_domain,
310 TRAPS);
311
312 // Lookup an instance or array class that has already been loaded
313 // either into the given class loader, or else into another class
314 // loader that is constrained (via loader constraints) to produce
315 // a consistent class. Do not take protection domains into account.
316 // Do not make any queries to class loaders; consult only the cache.
317 // Return NULL if the class is not found.
318 //
319 // This function is a strict superset of find_instance_or_array_klass.
320 // This function (the unchecked version) makes a conservative prediction
321 // of the result of the checked version, assuming successful lookup.
322 // If both functions return non-null, they must return the same value.
323 // Also, the unchecked version may sometimes be non-null where the
324 // checked version is null. This can occur in several ways:
325 // 1. No query has yet been made to the class loader.
326 // 2. The class loader was queried, but chose not to delegate.
327 // 3. ClassLoader.checkPackageAccess rejected a proposed protection domain.
328 // 4. Loading was attempted, but there was a linkage error of some sort.
329 // In all of these cases, the loader constraints on this type are
330 // satisfied, and it is safe for classes in the given class loader
331 // to manipulate strongly-typed values of the found class, subject
332 // to local linkage and access checks.
333 static Klass* find_constrained_instance_or_array_klass(Symbol* class_name,
334 Handle class_loader,
335 TRAPS);
336
337 static void classes_do(MetaspaceClosure* it);
338 // Iterate over all methods in all klasses
339
340 static void methods_do(void f(Method*));
341
342 // Garbage collection support
343
344 // Unload (that is, break root links to) all unmarked classes and
345 // loaders. Returns "true" iff something was unloaded.
346 static bool do_unloading(GCTimer* gc_timer);
347
348 // Applies "f->do_oop" to all root oops in the system dictionary.
349 // If include_handles is true (the default), then the handles in the
350 // vm_global OopStorage object are included.
351 static void oops_do(OopClosure* f, bool include_handles = true);
352
353 // System loader lock
354 static oop system_loader_lock() { return _system_loader_lock_obj; }
355
356 // Protection Domain Table
357 static ProtectionDomainCacheTable* pd_cache_table() { return _pd_cache_table; }
358
359 public:
360 // Printing
361 static void print();
362 static void print_on(outputStream* st);
363 static void dump(outputStream* st, bool verbose);
364
365 // Verification
366 static void verify();
367
368 // Initialization
369 static void initialize(TRAPS);
370
371 // Checked fast access to the well-known classes -- so that you don't try to use them
372 // before they are resolved.
373 static InstanceKlass* check_klass(InstanceKlass* k) {
374 assert(k != NULL, "klass not loaded");
375 return k;
376 }
377
378 static bool resolve_wk_klass(WKID id, TRAPS);
379 static void resolve_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS);
380 static void resolve_wk_klasses_through(WKID end_id, WKID &start_id, TRAPS) {
381 int limit = (int)end_id + 1;
382 resolve_wk_klasses_until((WKID) limit, start_id, THREAD);
383 }
384 static bool register_native(Klass* k, Symbol* name, Symbol* signature, address entry, TRAPS);
385 static Method* find_prefixed_native(Klass* k, Symbol* name, Symbol* signature, TRAPS);
386 public:
387 #define WK_KLASS_DECLARE(name, symbol) \
388 static InstanceKlass* name() { return check_klass(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); } \
389 static InstanceKlass** name##_addr() { \
390 return &_well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]; \
391 } \
392 static bool name##_is_loaded() { \
393 return _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)] != NULL; \
394 }
395 WK_KLASSES_DO(WK_KLASS_DECLARE);
396 #undef WK_KLASS_DECLARE
397
398 static InstanceKlass* well_known_klass(WKID id) {
399 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
400 return _well_known_klasses[id];
401 }
402
403 static InstanceKlass** well_known_klass_addr(WKID id) {
404 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
405 return &_well_known_klasses[id];
406 }
407 static void well_known_klasses_do(MetaspaceClosure* it);
408
409 // Local definition for direct access to the private array:
410 #define WK_KLASS(name) _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]
411
412 static InstanceKlass* box_klass(BasicType t) {
413 assert((uint)t < T_VOID+1, "range check");
414 return check_klass(_box_klasses[t]);
415 }
416 static BasicType box_klass_type(Klass* k); // inverse of box_klass
417 #ifdef ASSERT
418 static bool is_well_known_klass(Klass* k) {
419 return is_well_known_klass(k->name());
420 }
421 static bool is_well_known_klass(Symbol* class_name);
422 #endif
423
424 protected:
425 // Returns the class loader data to be used when looking up/updating the
426 // system dictionary.
427 static ClassLoaderData *class_loader_data(Handle class_loader) {
428 return ClassLoaderData::class_loader_data(class_loader());
429 }
430
431 public:
432 // Tells whether ClassLoader.checkPackageAccess is present
433 static bool has_checkPackageAccess() { return _has_checkPackageAccess; }
434
435 static bool Parameter_klass_loaded() { return WK_KLASS(reflect_Parameter_klass) != NULL; }
436 static bool Class_klass_loaded() { return WK_KLASS(Class_klass) != NULL; }
437 static bool Cloneable_klass_loaded() { return WK_KLASS(Cloneable_klass) != NULL; }
438 static bool Object_klass_loaded() { return WK_KLASS(Object_klass) != NULL; }
439 static bool ClassLoader_klass_loaded() { return WK_KLASS(ClassLoader_klass) != NULL; }
440
441 // Returns java system loader
442 static oop java_system_loader();
443
444 // Returns java platform loader
445 static oop java_platform_loader();
446
447 // Compute the java system and platform loaders
448 static void compute_java_loaders(TRAPS);
449
450 // Register a new class loader
451 static ClassLoaderData* register_loader(Handle class_loader);
452 protected:
453 // Mirrors for primitive classes (created eagerly)
454 static oop check_mirror(oop m) {
455 assert(m != NULL, "mirror not initialized");
456 return m;
457 }
458
459 public:
460 // Note: java_lang_Class::primitive_type is the inverse of java_mirror
461
462 // Check class loader constraints
463 static bool add_loader_constraint(Symbol* name, Handle loader1,
464 Handle loader2, TRAPS);
465 static Symbol* check_signature_loaders(Symbol* signature, Handle loader1,
466 Handle loader2, bool is_method, TRAPS);
467
468 // JSR 292
469 // find a java.lang.invoke.MethodHandle.invoke* method for a given signature
470 // (asks Java to compute it if necessary, except in a compiler thread)
471 static methodHandle find_method_handle_invoker(Klass* klass,
472 Symbol* name,
473 Symbol* signature,
474 Klass* accessing_klass,
475 Handle *appendix_result,
476 TRAPS);
477 // for a given signature, find the internal MethodHandle method (linkTo* or invokeBasic)
478 // (does not ask Java, since this is a low-level intrinsic defined by the JVM)
479 static methodHandle find_method_handle_intrinsic(vmIntrinsics::ID iid,
480 Symbol* signature,
481 TRAPS);
482
483 // compute java_mirror (java.lang.Class instance) for a type ("I", "[[B", "LFoo;", etc.)
484 // Either the accessing_klass or the CL/PD can be non-null, but not both.
485 static Handle find_java_mirror_for_type(Symbol* signature,
486 Klass* accessing_klass,
487 Handle class_loader,
488 Handle protection_domain,
489 SignatureStream::FailureMode failure_mode,
490 TRAPS);
491 static Handle find_java_mirror_for_type(Symbol* signature,
492 Klass* accessing_klass,
493 SignatureStream::FailureMode failure_mode,
494 TRAPS) {
495 // callee will fill in CL/PD from AK, if they are needed
496 return find_java_mirror_for_type(signature, accessing_klass, Handle(), Handle(),
497 failure_mode, THREAD);
498 }
499
500
501 // fast short-cut for the one-character case:
502 static oop find_java_mirror_for_type(char signature_char);
503
504 // find a java.lang.invoke.MethodType object for a given signature
505 // (asks Java to compute it if necessary, except in a compiler thread)
506 static Handle find_method_handle_type(Symbol* signature,
507 Klass* accessing_klass,
508 TRAPS);
509
510 // find a java.lang.Class object for a given signature
511 static Handle find_field_handle_type(Symbol* signature,
512 Klass* accessing_klass,
513 TRAPS);
514
515 // ask Java to compute a java.lang.invoke.MethodHandle object for a given CP entry
516 static Handle link_method_handle_constant(Klass* caller,
517 int ref_kind, //e.g., JVM_REF_invokeVirtual
518 Klass* callee,
519 Symbol* name,
520 Symbol* signature,
521 TRAPS);
522
523 // ask Java to compute a constant by invoking a BSM given a Dynamic_info CP entry
524 static void invoke_bootstrap_method(BootstrapInfo& bootstrap_specifier, TRAPS);
525
526 // Record the error when the first attempt to resolve a reference from a constant
527 // pool entry to a class fails.
528 static void add_resolution_error(const constantPoolHandle& pool, int which, Symbol* error,
529 Symbol* message);
530 static void delete_resolution_error(ConstantPool* pool);
531 static Symbol* find_resolution_error(const constantPoolHandle& pool, int which,
532 Symbol** message);
533
534
535 static ProtectionDomainCacheEntry* cache_get(Handle protection_domain);
536
537 protected:
538
539 enum Constants {
540 _loader_constraint_size = 107, // number of entries in constraint table
541 _resolution_error_size = 107, // number of entries in resolution error table
542 _invoke_method_size = 139, // number of entries in invoke method table
543 _placeholder_table_size = 1009 // number of entries in hash table for placeholders
544 };
545
546
547 // Static tables owned by the SystemDictionary
548
549 // Hashtable holding placeholders for classes being loaded.
550 static PlaceholderTable* _placeholders;
551
552 // Lock object for system class loader
553 static oop _system_loader_lock_obj;
554
555 // Constraints on class loaders
556 static LoaderConstraintTable* _loader_constraints;
557
558 // Resolution errors
559 static ResolutionErrorTable* _resolution_errors;
560
561 // Invoke methods (JSR 292)
562 static SymbolPropertyTable* _invoke_method_table;
563
564 // ProtectionDomain cache
565 static ProtectionDomainCacheTable* _pd_cache_table;
566
567 protected:
568 static void validate_protection_domain(InstanceKlass* klass,
569 Handle class_loader,
570 Handle protection_domain, TRAPS);
571
572 friend class VM_PopulateDumpSharedSpace;
573 friend class TraversePlaceholdersClosure;
574 static PlaceholderTable* placeholders() { return _placeholders; }
575 static LoaderConstraintTable* constraints() { return _loader_constraints; }
576 static ResolutionErrorTable* resolution_errors() { return _resolution_errors; }
577 static SymbolPropertyTable* invoke_method_table() { return _invoke_method_table; }
578
579 // Basic loading operations
580 static InstanceKlass* resolve_instance_class_or_null_helper(Symbol* name,
581 Handle class_loader,
582 Handle protection_domain,
583 TRAPS);
584 static InstanceKlass* resolve_instance_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
585 static Klass* resolve_array_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
586 static InstanceKlass* handle_parallel_super_load(Symbol* class_name, Symbol* supername, Handle class_loader, Handle protection_domain, Handle lockObject, TRAPS);
587 // Wait on SystemDictionary_lock; unlocks lockObject before
588 // waiting; relocks lockObject with correct recursion count
589 // after waiting, but before reentering SystemDictionary_lock
590 // to preserve lock order semantics.
591 static void double_lock_wait(Handle lockObject, TRAPS);
592 static void define_instance_class(InstanceKlass* k, TRAPS);
593 static InstanceKlass* find_or_define_instance_class(Symbol* class_name,
594 Handle class_loader,
595 InstanceKlass* k, TRAPS);
596 static bool is_shared_class_visible(Symbol* class_name, InstanceKlass* ik,
597 Handle class_loader, TRAPS);
598 static InstanceKlass* load_shared_class(InstanceKlass* ik,
599 Handle class_loader,
600 Handle protection_domain,
601 const ClassFileStream *cfs,
602 TRAPS);
603 static InstanceKlass* load_shared_boot_class(Symbol* class_name,
604 TRAPS);
605 static InstanceKlass* load_instance_class(Symbol* class_name, Handle class_loader, TRAPS);
606 static Handle compute_loader_lock_object(Handle class_loader, TRAPS);
607 static void check_loader_lock_contention(Handle loader_lock, TRAPS);
608 static bool is_parallelCapable(Handle class_loader);
609 static bool is_parallelDefine(Handle class_loader);
610
611 public:
612 static bool is_system_class_loader(oop class_loader);
613 static bool is_platform_class_loader(oop class_loader);
614
615 // Returns TRUE if the method is a non-public member of class java.lang.Object.
616 static bool is_nonpublic_Object_method(Method* m) {
617 assert(m != NULL, "Unexpected NULL Method*");
618 return !m->is_public() && m->method_holder() == SystemDictionary::Object_klass();
619 }
620
621 protected:
622 // Setup link to hierarchy
623 static void add_to_hierarchy(InstanceKlass* k, TRAPS);
624
625 // Basic find on loaded classes
626 static InstanceKlass* find_class(unsigned int hash,
627 Symbol* name, Dictionary* dictionary);
628 static InstanceKlass* find_class(Symbol* class_name, ClassLoaderData* loader_data);
629
630 // Basic find on classes in the midst of being loaded
631 static Symbol* find_placeholder(Symbol* name, ClassLoaderData* loader_data);
632
633 // Resolve well-known classes so they can be used like SystemDictionary::String_klass()
634 static void resolve_well_known_classes(TRAPS);
635
636 // Class loader constraints
637 static void check_constraints(unsigned int hash,
638 InstanceKlass* k, Handle loader,
639 bool defining, TRAPS);
640 static void update_dictionary(unsigned int d_hash,
641 int p_index, unsigned int p_hash,
642 InstanceKlass* k, Handle loader,
643 TRAPS);
644
645 static InstanceKlass* _well_known_klasses[];
646
647 // table of box klasses (int_klass, etc.)
648 static InstanceKlass* _box_klasses[T_VOID+1];
649
650 private:
651 static oop _java_system_loader;
652 static oop _java_platform_loader;
653
654 static bool _has_checkPackageAccess;
655
656 public:
657 static TableStatistics placeholders_statistics();
658 static TableStatistics loader_constraints_statistics();
659 static TableStatistics protection_domain_cache_statistics();
660 };
661
662 #endif // SHARE_CLASSFILE_SYSTEMDICTIONARY_HPP