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,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
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23 */
24
25 #ifndef SHARE_CLASSFILE_SYSTEMDICTIONARY_HPP
26 #define SHARE_CLASSFILE_SYSTEMDICTIONARY_HPP
27
28 #include "classfile/classLoader.hpp"
29 #include "jvmci/systemDictionary_jvmci.hpp"
30 #include "oops/fieldStreams.hpp"
31 #include "oops/objArrayOop.hpp"
32 #include "oops/symbol.hpp"
33 #include "runtime/java.hpp"
34 #include "runtime/reflectionUtils.hpp"
35 #include "runtime/signature.hpp"
36 #include "utilities/hashtable.hpp"
37
38 // The dictionary in each ClassLoaderData stores all loaded classes, either
39 // initiatied by its class loader or defined by its class loader:
40 //
41 // class loader -> ClassLoaderData -> [class, protection domain set]
42 //
43 // Classes are loaded lazily. The default VM class loader is
44 // represented as NULL.
45
46 // The underlying data structure is an open hash table (Dictionary) per
47 // ClassLoaderData with a fixed number of buckets. During loading the
48 // class loader object is locked, (for the VM loader a private lock object is used).
49 // The global SystemDictionary_lock is held for all additions into the ClassLoaderData
50 // dictionaries. TODO: fix lock granularity so that class loading can
51 // be done concurrently, but only by different loaders.
52 //
53 // During loading a placeholder (name, loader) is temporarily placed in
54 // a side data structure, and is used to detect ClassCircularityErrors
55 // and to perform verification during GC. A GC can occur in the midst
56 // of class loading, as we call out to Java, have to take locks, etc.
57 //
58 // When class loading is finished, a new entry is added to the dictionary
59 // of the class loader and the placeholder is removed. Note that the protection
60 // domain field of the dictionary entry has not yet been filled in when
61 // the "real" dictionary entry is created.
62 //
63 // Clients of this class who are interested in finding if a class has
64 // been completely loaded -- not classes in the process of being loaded --
65 // can read the dictionary unlocked. This is safe because
66 // - entries are only deleted at safepoints
67 // - readers cannot come to a safepoint while actively examining
68 // an entry (an entry cannot be deleted from under a reader)
69 // - entries must be fully formed before they are available to concurrent
70 // readers (we must ensure write ordering)
71 //
72 // Note that placeholders are deleted at any time, as they are removed
73 // when a class is completely loaded. Therefore, readers as well as writers
74 // of placeholders must hold the SystemDictionary_lock.
75 //
76
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 class OopStorage;
88
89 #define WK_KLASS_ENUM_NAME(kname) kname##_knum
90
91 // Certain classes, such as java.lang.Object and java.lang.String,
92 // are "well-known", in the sense that no class loader is allowed
93 // to provide a different definition.
94 //
95 // Each well-known class has a short klass name (like object_klass),
96 // and a vmSymbol name (like java_lang_Object).
97 //
98 // The order of these definitions is significant: the classes are
99 // resolved during early VM start-up by resolve_well_known_classes
100 // in this order. Changing the order may require careful restructuring
101 // of the VM start-up sequence.
102 //
103 #define WK_KLASSES_DO(do_klass) \
104 /* well-known classes */ \
105 do_klass(Object_klass, java_lang_Object ) \
106 do_klass(String_klass, java_lang_String ) \
107 do_klass(Class_klass, java_lang_Class ) \
108 do_klass(Cloneable_klass, java_lang_Cloneable ) \
109 do_klass(ClassLoader_klass, java_lang_ClassLoader ) \
110 do_klass(Serializable_klass, java_io_Serializable ) \
111 do_klass(System_klass, java_lang_System ) \
112 do_klass(Throwable_klass, java_lang_Throwable ) \
113 do_klass(Error_klass, java_lang_Error ) \
114 do_klass(ThreadDeath_klass, java_lang_ThreadDeath ) \
115 do_klass(Exception_klass, java_lang_Exception ) \
116 do_klass(RuntimeException_klass, java_lang_RuntimeException ) \
117 do_klass(SecurityManager_klass, java_lang_SecurityManager ) \
118 do_klass(ProtectionDomain_klass, java_security_ProtectionDomain ) \
119 do_klass(AccessControlContext_klass, java_security_AccessControlContext ) \
120 do_klass(AccessController_klass, java_security_AccessController ) \
121 do_klass(SecureClassLoader_klass, java_security_SecureClassLoader ) \
122 do_klass(ClassNotFoundException_klass, java_lang_ClassNotFoundException ) \
123 do_klass(NoClassDefFoundError_klass, java_lang_NoClassDefFoundError ) \
124 do_klass(LinkageError_klass, java_lang_LinkageError ) \
125 do_klass(ClassCastException_klass, java_lang_ClassCastException ) \
126 do_klass(ArrayStoreException_klass, java_lang_ArrayStoreException ) \
127 do_klass(VirtualMachineError_klass, java_lang_VirtualMachineError ) \
128 do_klass(OutOfMemoryError_klass, java_lang_OutOfMemoryError ) \
129 do_klass(StackOverflowError_klass, java_lang_StackOverflowError ) \
130 do_klass(IllegalMonitorStateException_klass, java_lang_IllegalMonitorStateException ) \
131 do_klass(Reference_klass, java_lang_ref_Reference ) \
132 \
133 /* ref klasses and set reference types */ \
134 do_klass(SoftReference_klass, java_lang_ref_SoftReference ) \
135 do_klass(WeakReference_klass, java_lang_ref_WeakReference ) \
136 do_klass(FinalReference_klass, java_lang_ref_FinalReference ) \
137 do_klass(PhantomReference_klass, java_lang_ref_PhantomReference ) \
138 do_klass(Finalizer_klass, java_lang_ref_Finalizer ) \
139 \
140 do_klass(Thread_klass, java_lang_Thread ) \
141 do_klass(ThreadGroup_klass, java_lang_ThreadGroup ) \
142 do_klass(Properties_klass, java_util_Properties ) \
143 do_klass(Module_klass, java_lang_Module ) \
144 do_klass(reflect_AccessibleObject_klass, java_lang_reflect_AccessibleObject ) \
145 do_klass(reflect_Field_klass, java_lang_reflect_Field ) \
146 do_klass(reflect_Parameter_klass, java_lang_reflect_Parameter ) \
147 do_klass(reflect_Method_klass, java_lang_reflect_Method ) \
148 do_klass(reflect_Constructor_klass, java_lang_reflect_Constructor ) \
149 \
150 /* NOTE: needed too early in bootstrapping process to have checks based on JDK version */ \
151 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \
152 do_klass(reflect_MagicAccessorImpl_klass, reflect_MagicAccessorImpl ) \
153 do_klass(reflect_MethodAccessorImpl_klass, reflect_MethodAccessorImpl ) \
154 do_klass(reflect_ConstructorAccessorImpl_klass, reflect_ConstructorAccessorImpl ) \
155 do_klass(reflect_DelegatingClassLoader_klass, reflect_DelegatingClassLoader ) \
156 do_klass(reflect_ConstantPool_klass, reflect_ConstantPool ) \
157 do_klass(reflect_UnsafeStaticFieldAccessorImpl_klass, reflect_UnsafeStaticFieldAccessorImpl ) \
158 do_klass(reflect_CallerSensitive_klass, reflect_CallerSensitive ) \
159 \
160 /* support for dynamic typing; it's OK if these are NULL in earlier JDKs */ \
161 do_klass(DirectMethodHandle_klass, java_lang_invoke_DirectMethodHandle ) \
162 do_klass(MethodHandle_klass, java_lang_invoke_MethodHandle ) \
163 do_klass(VarHandle_klass, java_lang_invoke_VarHandle ) \
164 do_klass(MemberName_klass, java_lang_invoke_MemberName ) \
165 do_klass(ResolvedMethodName_klass, java_lang_invoke_ResolvedMethodName ) \
166 do_klass(MethodHandleNatives_klass, java_lang_invoke_MethodHandleNatives ) \
167 do_klass(LambdaForm_klass, java_lang_invoke_LambdaForm ) \
168 do_klass(MethodType_klass, java_lang_invoke_MethodType ) \
169 do_klass(BootstrapMethodError_klass, java_lang_BootstrapMethodError ) \
170 do_klass(CallSite_klass, java_lang_invoke_CallSite ) \
171 do_klass(Context_klass, java_lang_invoke_MethodHandleNatives_CallSiteContext ) \
172 do_klass(ConstantCallSite_klass, java_lang_invoke_ConstantCallSite ) \
173 do_klass(MutableCallSite_klass, java_lang_invoke_MutableCallSite ) \
174 do_klass(ValueBootstrapMethods_klass, java_lang_invoke_ValueBootstrapMethods ) \
175 do_klass(VolatileCallSite_klass, java_lang_invoke_VolatileCallSite ) \
176 /* Note: MethodHandle must be first, and VolatileCallSite last in group */ \
177 \
178 do_klass(AssertionStatusDirectives_klass, java_lang_AssertionStatusDirectives ) \
179 do_klass(StringBuffer_klass, java_lang_StringBuffer ) \
180 do_klass(StringBuilder_klass, java_lang_StringBuilder ) \
181 do_klass(internal_Unsafe_klass, jdk_internal_misc_Unsafe ) \
182 do_klass(module_Modules_klass, jdk_internal_module_Modules ) \
183 \
184 /* support for CDS */ \
185 do_klass(ByteArrayInputStream_klass, java_io_ByteArrayInputStream ) \
186 do_klass(URL_klass, java_net_URL ) \
187 do_klass(Jar_Manifest_klass, java_util_jar_Manifest ) \
188 do_klass(jdk_internal_loader_ClassLoaders_klass, jdk_internal_loader_ClassLoaders ) \
189 do_klass(jdk_internal_loader_ClassLoaders_AppClassLoader_klass, jdk_internal_loader_ClassLoaders_AppClassLoader) \
190 do_klass(jdk_internal_loader_ClassLoaders_PlatformClassLoader_klass, jdk_internal_loader_ClassLoaders_PlatformClassLoader) \
191 do_klass(CodeSource_klass, java_security_CodeSource ) \
192 \
193 do_klass(StackTraceElement_klass, java_lang_StackTraceElement ) \
194 \
195 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \
196 do_klass(nio_Buffer_klass, java_nio_Buffer ) \
197 \
198 /* Stack Walking */ \
199 do_klass(StackWalker_klass, java_lang_StackWalker ) \
200 do_klass(AbstractStackWalker_klass, java_lang_StackStreamFactory_AbstractStackWalker ) \
201 do_klass(StackFrameInfo_klass, java_lang_StackFrameInfo ) \
202 do_klass(LiveStackFrameInfo_klass, java_lang_LiveStackFrameInfo ) \
203 \
204 /* support for stack dump lock analysis */ \
205 do_klass(java_util_concurrent_locks_AbstractOwnableSynchronizer_klass, java_util_concurrent_locks_AbstractOwnableSynchronizer) \
206 \
207 /* boxing klasses */ \
208 do_klass(Boolean_klass, java_lang_Boolean ) \
209 do_klass(Character_klass, java_lang_Character ) \
210 do_klass(Float_klass, java_lang_Float ) \
211 do_klass(Double_klass, java_lang_Double ) \
212 do_klass(Byte_klass, java_lang_Byte ) \
213 do_klass(Short_klass, java_lang_Short ) \
214 do_klass(Integer_klass, java_lang_Integer ) \
215 do_klass(Long_klass, java_lang_Long ) \
216 \
217 \
218 /* JVMCI classes. These are loaded on-demand. */ \
219 JVMCI_WK_KLASSES_DO(do_klass) \
220 \
221 /*end*/
222
223
224 class SystemDictionary : AllStatic {
225 friend class VMStructs;
226 friend class SystemDictionaryHandles;
227
228 public:
229 enum WKID {
230 NO_WKID = 0,
231
232 #define WK_KLASS_ENUM(name, symbol) WK_KLASS_ENUM_NAME(name), WK_KLASS_ENUM_NAME(symbol) = WK_KLASS_ENUM_NAME(name),
233 WK_KLASSES_DO(WK_KLASS_ENUM)
234 #undef WK_KLASS_ENUM
235
236 WKID_LIMIT,
237
238 #if INCLUDE_JVMCI
239 FIRST_JVMCI_WKID = WK_KLASS_ENUM_NAME(JVMCI_klass),
240 LAST_JVMCI_WKID = WK_KLASS_ENUM_NAME(Value_klass),
241 #endif
242
243 FIRST_WKID = NO_WKID + 1
244 };
245
246 // Returns a class with a given class name and class loader. Loads the
247 // class if needed. If not found a NoClassDefFoundError or a
248 // ClassNotFoundException is thrown, depending on the value on the
249 // throw_error flag. For most uses the throw_error argument should be set
250 // to true.
251
252 static Klass* resolve_or_fail(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS);
253 // Convenient call for null loader and protection domain.
254 static Klass* resolve_or_fail(Symbol* class_name, bool throw_error, TRAPS);
255 protected:
256 // handle error translation for resolve_or_null results
257 static Klass* handle_resolution_exception(Symbol* class_name, bool throw_error, Klass* klass, TRAPS);
258
259 public:
260
261 // Returns a class with a given class name and class loader.
262 // Loads the class if needed. If not found NULL is returned.
263 static Klass* resolve_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
264 // Version with null loader and protection domain
265 static Klass* resolve_or_null(Symbol* class_name, TRAPS);
266
267 // Resolve a superclass or superinterface. Called from ClassFileParser,
268 // parse_interfaces, resolve_instance_class_or_null, load_shared_class
269 // "child_name" is the class whose super class or interface is being resolved.
270 static InstanceKlass* resolve_super_or_fail(Symbol* child_name,
271 Symbol* class_name,
272 Handle class_loader,
273 Handle protection_domain,
274 bool is_superclass,
275 TRAPS);
276
277 static Klass* resolve_flattenable_field_or_fail(AllFieldStream* fs,
278 Handle class_loader,
279 Handle protection_domain,
280 bool throw_error,
281 TRAPS);
282
283 // Parse new stream. This won't update the dictionary or
284 // class hierarchy, simply parse the stream. Used by JVMTI RedefineClasses.
285 // Also used by Unsafe_DefineAnonymousClass
286 static InstanceKlass* parse_stream(Symbol* class_name,
287 Handle class_loader,
288 Handle protection_domain,
289 ClassFileStream* st,
290 TRAPS) {
291 return parse_stream(class_name,
292 class_loader,
293 protection_domain,
294 st,
295 NULL, // unsafe_anonymous_host
296 NULL, // cp_patches
297 THREAD);
298 }
299 static InstanceKlass* parse_stream(Symbol* class_name,
300 Handle class_loader,
301 Handle protection_domain,
302 ClassFileStream* st,
303 const InstanceKlass* unsafe_anonymous_host,
304 GrowableArray<Handle>* cp_patches,
305 TRAPS);
306
307 // Resolve from stream (called by jni_DefineClass and JVM_DefineClass)
308 static InstanceKlass* resolve_from_stream(Symbol* class_name,
309 Handle class_loader,
310 Handle protection_domain,
311 ClassFileStream* st,
312 TRAPS);
313
314 // Lookup an already loaded class. If not found NULL is returned.
315 static Klass* find(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
316
317 // Lookup an already loaded instance or array class.
318 // Do not make any queries to class loaders; consult only the cache.
319 // If not found NULL is returned.
320 static Klass* find_instance_or_array_klass(Symbol* class_name,
321 Handle class_loader,
322 Handle protection_domain,
323 TRAPS);
324
325 // Lookup an instance or array class that has already been loaded
326 // either into the given class loader, or else into another class
327 // loader that is constrained (via loader constraints) to produce
328 // a consistent class. Do not take protection domains into account.
329 // Do not make any queries to class loaders; consult only the cache.
330 // Return NULL if the class is not found.
331 //
332 // This function is a strict superset of find_instance_or_array_klass.
333 // This function (the unchecked version) makes a conservative prediction
334 // of the result of the checked version, assuming successful lookup.
335 // If both functions return non-null, they must return the same value.
336 // Also, the unchecked version may sometimes be non-null where the
337 // checked version is null. This can occur in several ways:
338 // 1. No query has yet been made to the class loader.
339 // 2. The class loader was queried, but chose not to delegate.
340 // 3. ClassLoader.checkPackageAccess rejected a proposed protection domain.
341 // 4. Loading was attempted, but there was a linkage error of some sort.
342 // In all of these cases, the loader constraints on this type are
343 // satisfied, and it is safe for classes in the given class loader
344 // to manipulate strongly-typed values of the found class, subject
345 // to local linkage and access checks.
346 static Klass* find_constrained_instance_or_array_klass(Symbol* class_name,
347 Handle class_loader,
348 TRAPS);
349
350 static void classes_do(MetaspaceClosure* it);
351 // Iterate over all methods in all klasses
352
353 static void methods_do(void f(Method*));
354
355 // Garbage collection support
356
357 // Unload (that is, break root links to) all unmarked classes and
358 // loaders. Returns "true" iff something was unloaded.
359 static bool do_unloading(GCTimer* gc_timer);
360
361 // Applies "f->do_oop" to all root oops in the system dictionary.
362 static void oops_do(OopClosure* f);
363
364 // System loader lock
365 static oop system_loader_lock() { return _system_loader_lock_obj; }
366
367 // Protection Domain Table
368 static ProtectionDomainCacheTable* pd_cache_table() { return _pd_cache_table; }
369
370 public:
371 // Printing
372 static void print() { return print_on(tty); }
373 static void print_on(outputStream* st);
374 static void dump(outputStream* st, bool verbose);
375
376 // Monotonically increasing counter which grows as classes are
377 // loaded or modifications such as hot-swapping or setting/removing
378 // of breakpoints are performed
379 static inline int number_of_modifications() { assert_locked_or_safepoint(Compile_lock); return _number_of_modifications; }
380 // Needed by evolution and breakpoint code
381 static inline void notice_modification() { assert_locked_or_safepoint(Compile_lock); ++_number_of_modifications; }
382
383 // Verification
384 static void verify();
385
386 // Initialization
387 static void initialize(TRAPS);
388
389 // Checked fast access to the well-known classes -- so that you don't try to use them
390 // before they are resolved.
391 static InstanceKlass* check_klass(InstanceKlass* k) {
392 assert(k != NULL, "klass not loaded");
393 return k;
394 }
395
396 static bool resolve_wk_klass(WKID id, TRAPS);
397 static InstanceKlass* check_klass_ValhallaClasses(InstanceKlass* k) { return k; }
398 static void resolve_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS);
399 static void resolve_wk_klasses_through(WKID end_id, WKID &start_id, TRAPS) {
400 int limit = (int)end_id + 1;
401 resolve_wk_klasses_until((WKID) limit, start_id, THREAD);
402 }
403
404 public:
405 #define WK_KLASS_DECLARE(name, symbol) \
406 static InstanceKlass* name() { return check_klass(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); } \
407 static InstanceKlass** name##_addr() { \
408 return &_well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]; \
409 } \
410 static bool name##_is_loaded() { \
411 return _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)] != NULL; \
412 }
413 WK_KLASSES_DO(WK_KLASS_DECLARE);
414 #undef WK_KLASS_DECLARE
415
416 static InstanceKlass* well_known_klass(WKID id) {
417 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
418 return _well_known_klasses[id];
419 }
420
421 static InstanceKlass** well_known_klass_addr(WKID id) {
422 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
423 return &_well_known_klasses[id];
424 }
425 static void well_known_klasses_do(MetaspaceClosure* it);
426
427 // Local definition for direct access to the private array:
428 #define WK_KLASS(name) _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]
429
430 static InstanceKlass* box_klass(BasicType t) {
431 assert((uint)t < T_VOID+1, "range check");
432 return check_klass(_box_klasses[t]);
433 }
434 static BasicType box_klass_type(Klass* k); // inverse of box_klass
435 #ifdef ASSERT
436 static bool is_well_known_klass(Klass* k) {
437 return is_well_known_klass(k->name());
438 }
439 static bool is_well_known_klass(Symbol* class_name);
440 #endif
441
442 protected:
443 // Returns the class loader data to be used when looking up/updating the
444 // system dictionary.
445 static ClassLoaderData *class_loader_data(Handle class_loader) {
446 return ClassLoaderData::class_loader_data(class_loader());
447 }
448
449 public:
450 // Tells whether ClassLoader.checkPackageAccess is present
451 static bool has_checkPackageAccess() { return _has_checkPackageAccess; }
452
453 static bool Parameter_klass_loaded() { return WK_KLASS(reflect_Parameter_klass) != NULL; }
454 static bool Class_klass_loaded() { return WK_KLASS(Class_klass) != NULL; }
455 static bool Cloneable_klass_loaded() { return WK_KLASS(Cloneable_klass) != NULL; }
456 static bool Object_klass_loaded() { return WK_KLASS(Object_klass) != NULL; }
457 static bool ClassLoader_klass_loaded() { return WK_KLASS(ClassLoader_klass) != NULL; }
458
459 // Returns java system loader
460 static oop java_system_loader();
461
462 // Returns java platform loader
463 static oop java_platform_loader();
464
465 // Compute the java system and platform loaders
466 static void compute_java_loaders(TRAPS);
467
468 // Register a new class loader
469 static ClassLoaderData* register_loader(Handle class_loader);
470 protected:
471 // Mirrors for primitive classes (created eagerly)
472 static oop check_mirror(oop m) {
473 assert(m != NULL, "mirror not initialized");
474 return m;
475 }
476
477 public:
478 // Note: java_lang_Class::primitive_type is the inverse of java_mirror
479
480 // Check class loader constraints
481 static bool add_loader_constraint(Symbol* name, Handle loader1,
482 Handle loader2, TRAPS);
483 static Symbol* check_signature_loaders(Symbol* signature, Handle loader1,
484 Handle loader2, bool is_method, TRAPS);
485
486 // JSR 292
487 // find a java.lang.invoke.MethodHandle.invoke* method for a given signature
488 // (asks Java to compute it if necessary, except in a compiler thread)
489 static methodHandle find_method_handle_invoker(Klass* klass,
490 Symbol* name,
491 Symbol* signature,
492 Klass* accessing_klass,
493 Handle *appendix_result,
494 Handle *method_type_result,
495 TRAPS);
496 // for a given signature, find the internal MethodHandle method (linkTo* or invokeBasic)
497 // (does not ask Java, since this is a low-level intrinsic defined by the JVM)
498 static methodHandle find_method_handle_intrinsic(vmIntrinsics::ID iid,
499 Symbol* signature,
500 TRAPS);
501
502 // compute java_mirror (java.lang.Class instance) for a type ("I", "[[B", "LFoo;", etc.)
503 // Either the accessing_klass or the CL/PD can be non-null, but not both.
504 static Handle find_java_mirror_for_type(Symbol* signature,
505 Klass* accessing_klass,
506 Handle class_loader,
507 Handle protection_domain,
508 SignatureStream::FailureMode failure_mode,
509 TRAPS);
510 static Handle find_java_mirror_for_type(Symbol* signature,
511 Klass* accessing_klass,
512 SignatureStream::FailureMode failure_mode,
513 TRAPS) {
514 // callee will fill in CL/PD from AK, if they are needed
515 return find_java_mirror_for_type(signature, accessing_klass, Handle(), Handle(),
516 failure_mode, THREAD);
517 }
518
519
520 // fast short-cut for the one-character case:
521 static oop find_java_mirror_for_type(char signature_char);
522
523 // find a java.lang.invoke.MethodType object for a given signature
524 // (asks Java to compute it if necessary, except in a compiler thread)
525 static Handle find_method_handle_type(Symbol* signature,
526 Klass* accessing_klass,
527 TRAPS);
528
529 // find a java.lang.Class object for a given signature
530 static Handle find_field_handle_type(Symbol* signature,
531 Klass* accessing_klass,
532 TRAPS);
533
534 // ask Java to compute a java.lang.invoke.MethodHandle object for a given CP entry
535 static Handle link_method_handle_constant(Klass* caller,
536 int ref_kind, //e.g., JVM_REF_invokeVirtual
537 Klass* callee,
538 Symbol* name,
539 Symbol* signature,
540 TRAPS);
541
542 // ask Java to compute a constant by invoking a BSM given a Dynamic_info CP entry
543 static Handle link_dynamic_constant(Klass* caller,
544 int condy_index,
545 Handle bootstrap_specifier,
546 Symbol* name,
547 Symbol* type,
548 TRAPS);
549
550 // ask Java to create a dynamic call site, while linking an invokedynamic op
551 static methodHandle find_dynamic_call_site_invoker(Klass* caller,
552 int indy_index,
553 Handle bootstrap_method,
554 Symbol* name,
555 Symbol* type,
556 Handle *appendix_result,
557 Handle *method_type_result,
558 TRAPS);
559
560 // Record the error when the first attempt to resolve a reference from a constant
561 // pool entry to a class fails.
562 static void add_resolution_error(const constantPoolHandle& pool, int which, Symbol* error,
563 Symbol* message);
564 static void delete_resolution_error(ConstantPool* pool);
565 static Symbol* find_resolution_error(const constantPoolHandle& pool, int which,
566 Symbol** message);
567
568
569 static ProtectionDomainCacheEntry* cache_get(Handle protection_domain);
570
571 protected:
572
573 enum Constants {
574 _loader_constraint_size = 107, // number of entries in constraint table
575 _resolution_error_size = 107, // number of entries in resolution error table
576 _invoke_method_size = 139, // number of entries in invoke method table
577 _placeholder_table_size = 1009 // number of entries in hash table for placeholders
578 };
579
580
581 // Static tables owned by the SystemDictionary
582
583 // Hashtable holding placeholders for classes being loaded.
584 static PlaceholderTable* _placeholders;
585
586 // Monotonically increasing counter which grows with
587 // loading classes as well as hot-swapping and breakpoint setting
588 // and removal.
589 static int _number_of_modifications;
590
591 // Lock object for system class loader
592 static oop _system_loader_lock_obj;
593
594 // Constraints on class loaders
595 static LoaderConstraintTable* _loader_constraints;
596
597 // Resolution errors
598 static ResolutionErrorTable* _resolution_errors;
599
600 // Invoke methods (JSR 292)
601 static SymbolPropertyTable* _invoke_method_table;
602
603 // ProtectionDomain cache
604 static ProtectionDomainCacheTable* _pd_cache_table;
605
606 // VM weak OopStorage object.
607 static OopStorage* _vm_weak_oop_storage;
608
609 protected:
610 static void validate_protection_domain(InstanceKlass* klass,
611 Handle class_loader,
612 Handle protection_domain, TRAPS);
613
614 friend class VM_PopulateDumpSharedSpace;
615 friend class TraversePlaceholdersClosure;
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 InstanceKlass* resolve_instance_class_or_null_helper(Symbol* name,
623 Handle class_loader,
624 Handle protection_domain,
625 TRAPS);
626 static InstanceKlass* resolve_instance_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
627 static Klass* resolve_array_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
628 static InstanceKlass* handle_parallel_super_load(Symbol* class_name, Symbol* supername, Handle class_loader, Handle protection_domain, Handle lockObject, TRAPS);
629 // Wait on SystemDictionary_lock; unlocks lockObject before
630 // waiting; relocks lockObject with correct recursion count
631 // after waiting, but before reentering SystemDictionary_lock
632 // to preserve lock order semantics.
633 static void double_lock_wait(Handle lockObject, TRAPS);
634 static void define_instance_class(InstanceKlass* k, TRAPS);
635 static InstanceKlass* find_or_define_instance_class(Symbol* class_name,
636 Handle class_loader,
637 InstanceKlass* k, TRAPS);
638 static bool is_shared_class_visible(Symbol* class_name, InstanceKlass* ik,
639 Handle class_loader, TRAPS);
640 static InstanceKlass* load_shared_class(InstanceKlass* ik,
641 Handle class_loader,
642 Handle protection_domain,
643 TRAPS);
644 static InstanceKlass* load_shared_boot_class(Symbol* class_name,
645 TRAPS);
646 static InstanceKlass* load_instance_class(Symbol* class_name, Handle class_loader, TRAPS);
647 static Handle compute_loader_lock_object(Handle class_loader, TRAPS);
648 static void check_loader_lock_contention(Handle loader_lock, TRAPS);
649 static bool is_parallelCapable(Handle class_loader);
650 static bool is_parallelDefine(Handle class_loader);
651
652 public:
653 static bool is_system_class_loader(oop class_loader);
654 static bool is_platform_class_loader(oop class_loader);
655
656 // Returns TRUE if the method is a non-public member of class java.lang.Object.
657 static bool is_nonpublic_Object_method(Method* m) {
658 assert(m != NULL, "Unexpected NULL Method*");
659 return !m->is_public() && m->method_holder() == SystemDictionary::Object_klass();
660 }
661
662 static void initialize_oop_storage();
663 static OopStorage* vm_weak_oop_storage();
664
665 protected:
666 // Setup link to hierarchy
667 static void add_to_hierarchy(InstanceKlass* k, TRAPS);
668
669 // Basic find on loaded classes
670 static InstanceKlass* find_class(unsigned int hash,
671 Symbol* name, Dictionary* dictionary);
672 static InstanceKlass* find_class(Symbol* class_name, ClassLoaderData* loader_data);
673
674 // Basic find on classes in the midst of being loaded
675 static Symbol* find_placeholder(Symbol* name, ClassLoaderData* loader_data);
676
677 // Add a placeholder for a class being loaded
678 static void add_placeholder(int index,
679 Symbol* class_name,
680 ClassLoaderData* loader_data);
681 static void remove_placeholder(int index,
682 Symbol* class_name,
683 ClassLoaderData* loader_data);
684
685 // Performs cleanups after resolve_super_or_fail. This typically needs
686 // to be called on failure.
687 // Won't throw, but can block.
688 static void resolution_cleanups(Symbol* class_name,
689 ClassLoaderData* loader_data,
690 TRAPS);
691
692 // Resolve well-known classes so they can be used like SystemDictionary::String_klass()
693 static void resolve_well_known_classes(TRAPS);
694
695 // Class loader constraints
696 static void check_constraints(unsigned int hash,
697 InstanceKlass* k, Handle loader,
698 bool defining, TRAPS);
699 static void update_dictionary(unsigned int d_hash,
700 int p_index, unsigned int p_hash,
701 InstanceKlass* k, Handle loader,
702 TRAPS);
703
704 static InstanceKlass* _well_known_klasses[];
705
706 // table of box klasses (int_klass, etc.)
707 static InstanceKlass* _box_klasses[T_VOID+1];
708
709 private:
710 static oop _java_system_loader;
711 static oop _java_platform_loader;
712
713 static bool _has_checkPackageAccess;
714 };
715
716 #endif // SHARE_CLASSFILE_SYSTEMDICTIONARY_HPP