1 /*
2 * Copyright (c) 1997, 2018, 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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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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23 */
24
25 #ifndef SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP
26 #define SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP
27
28 #include "classfile/classLoader.hpp"
29 #include "classfile/systemDictionary_ext.hpp"
30 #include "jvmci/systemDictionary_jvmci.hpp"
31 #include "oops/objArrayOop.hpp"
32 #include "oops/symbol.hpp"
33 #include "runtime/java.hpp"
34 #include "runtime/reflectionUtils.hpp"
35 #include "runtime/signature.hpp"
36 #include "utilities/hashtable.hpp"
37 #include "utilities/hashtable.inline.hpp"
38
39 // The dictionary in each ClassLoaderData stores all loaded classes, either
40 // initiatied by its class loader or defined by its class loader:
41 //
42 // class loader -> ClassLoaderData -> [class, protection domain set]
43 //
44 // Classes are loaded lazily. The default VM class loader is
45 // represented as NULL.
46
47 // The underlying data structure is an open hash table (Dictionary) per
48 // ClassLoaderData with a fixed number of buckets. During loading the
49 // class loader object is locked, (for the VM loader a private lock object is used).
50 // The global SystemDictionary_lock is held for all additions into the ClassLoaderData
51 // dictionaries. TODO: fix lock granularity so that class loading can
52 // be done concurrently, but only by different loaders.
53 //
54 // During loading a placeholder (name, loader) is temporarily placed in
55 // a side data structure, and is used to detect ClassCircularityErrors
56 // and to perform verification during GC. A GC can occur in the midst
57 // of class loading, as we call out to Java, have to take locks, etc.
58 //
59 // When class loading is finished, a new entry is added to the dictionary
60 // of the class loader and the placeholder is removed. Note that the protection
61 // domain field of the dictionary entry has not yet been filled in when
62 // the "real" dictionary entry is created.
63 //
64 // Clients of this class who are interested in finding if a class has
65 // been completely loaded -- not classes in the process of being loaded --
66 // can read the dictionary unlocked. This is safe because
67 // - entries are only deleted at safepoints
68 // - readers cannot come to a safepoint while actively examining
69 // an entry (an entry cannot be deleted from under a reader)
70 // - entries must be fully formed before they are available to concurrent
71 // readers (we must ensure write ordering)
72 //
73 // Note that placeholders are deleted at any time, as they are removed
74 // when a class is completely loaded. Therefore, readers as well as writers
75 // of placeholders must hold the SystemDictionary_lock.
76 //
77
78 class ClassFileStream;
79 class Dictionary;
80 class PlaceholderTable;
81 class LoaderConstraintTable;
82 template <MEMFLAGS F> class HashtableBucket;
83 class ResolutionErrorTable;
84 class SymbolPropertyTable;
85 class ProtectionDomainCacheTable;
86 class ProtectionDomainCacheEntry;
87 class GCTimer;
88
89 // Certain classes are preloaded, such as java.lang.Object and java.lang.String.
90 // They are all "well-known", in the sense that no class loader is allowed
91 // to provide a different definition.
92 //
93 // These klasses must all have names defined in vmSymbols.
94
95 #define WK_KLASS_ENUM_NAME(kname) kname##_knum
96
97 // Each well-known class has a short klass name (like object_klass),
98 // a vmSymbol name (like java_lang_Object), and a flag word
99 // that makes some minor distinctions, like whether the klass
100 // is preloaded, optional, release-specific, etc.
101 // The order of these definitions is significant; it is the order in which
102 // preloading is actually performed by initialize_preloaded_classes.
103
104 #define WK_KLASSES_DO(do_klass) \
105 /* well-known classes */ \
106 do_klass(Object_klass, java_lang_Object, Pre ) \
107 do_klass(String_klass, java_lang_String, Pre ) \
108 do_klass(Class_klass, java_lang_Class, Pre ) \
109 do_klass(Cloneable_klass, java_lang_Cloneable, Pre ) \
110 do_klass(ClassLoader_klass, java_lang_ClassLoader, Pre ) \
111 do_klass(Serializable_klass, java_io_Serializable, Pre ) \
112 do_klass(System_klass, java_lang_System, Pre ) \
113 do_klass(Throwable_klass, java_lang_Throwable, Pre ) \
114 do_klass(Error_klass, java_lang_Error, Pre ) \
115 do_klass(ThreadDeath_klass, java_lang_ThreadDeath, Pre ) \
116 do_klass(Exception_klass, java_lang_Exception, Pre ) \
117 do_klass(RuntimeException_klass, java_lang_RuntimeException, Pre ) \
118 do_klass(SecurityManager_klass, java_lang_SecurityManager, Pre ) \
119 do_klass(ProtectionDomain_klass, java_security_ProtectionDomain, Pre ) \
120 do_klass(AccessControlContext_klass, java_security_AccessControlContext, Pre ) \
121 do_klass(SecureClassLoader_klass, java_security_SecureClassLoader, Pre ) \
122 do_klass(ClassNotFoundException_klass, java_lang_ClassNotFoundException, Pre ) \
123 do_klass(NoClassDefFoundError_klass, java_lang_NoClassDefFoundError, Pre ) \
124 do_klass(LinkageError_klass, java_lang_LinkageError, Pre ) \
125 do_klass(ClassCastException_klass, java_lang_ClassCastException, Pre ) \
126 do_klass(ArrayStoreException_klass, java_lang_ArrayStoreException, Pre ) \
127 do_klass(VirtualMachineError_klass, java_lang_VirtualMachineError, Pre ) \
128 do_klass(OutOfMemoryError_klass, java_lang_OutOfMemoryError, Pre ) \
129 do_klass(StackOverflowError_klass, java_lang_StackOverflowError, Pre ) \
130 do_klass(IllegalMonitorStateException_klass, java_lang_IllegalMonitorStateException, Pre ) \
131 do_klass(Reference_klass, java_lang_ref_Reference, Pre ) \
132 \
133 /* Preload ref klasses and set reference types */ \
134 do_klass(SoftReference_klass, java_lang_ref_SoftReference, Pre ) \
135 do_klass(WeakReference_klass, java_lang_ref_WeakReference, Pre ) \
136 do_klass(FinalReference_klass, java_lang_ref_FinalReference, Pre ) \
137 do_klass(PhantomReference_klass, java_lang_ref_PhantomReference, Pre ) \
138 do_klass(Finalizer_klass, java_lang_ref_Finalizer, Pre ) \
139 \
140 do_klass(Thread_klass, java_lang_Thread, Pre ) \
141 do_klass(ThreadGroup_klass, java_lang_ThreadGroup, Pre ) \
142 do_klass(Properties_klass, java_util_Properties, Pre ) \
143 do_klass(Module_klass, java_lang_Module, Pre ) \
144 do_klass(reflect_AccessibleObject_klass, java_lang_reflect_AccessibleObject, Pre ) \
145 do_klass(reflect_Field_klass, java_lang_reflect_Field, Pre ) \
146 do_klass(reflect_Parameter_klass, java_lang_reflect_Parameter, Opt ) \
147 do_klass(reflect_Method_klass, java_lang_reflect_Method, Pre ) \
148 do_klass(reflect_Constructor_klass, java_lang_reflect_Constructor, Pre ) \
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, Opt ) \
153 do_klass(reflect_MethodAccessorImpl_klass, reflect_MethodAccessorImpl, Pre ) \
154 do_klass(reflect_ConstructorAccessorImpl_klass, reflect_ConstructorAccessorImpl, Pre ) \
155 do_klass(reflect_DelegatingClassLoader_klass, reflect_DelegatingClassLoader, Opt ) \
156 do_klass(reflect_ConstantPool_klass, reflect_ConstantPool, Opt ) \
157 do_klass(reflect_UnsafeStaticFieldAccessorImpl_klass, reflect_UnsafeStaticFieldAccessorImpl, Opt ) \
158 do_klass(reflect_CallerSensitive_klass, reflect_CallerSensitive, Opt ) \
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, Opt ) \
162 do_klass(MethodHandle_klass, java_lang_invoke_MethodHandle, Pre ) \
163 do_klass(VarHandle_klass, java_lang_invoke_VarHandle, Pre ) \
164 do_klass(MemberName_klass, java_lang_invoke_MemberName, Pre ) \
165 do_klass(ResolvedMethodName_klass, java_lang_invoke_ResolvedMethodName, Pre ) \
166 do_klass(MethodHandleNatives_klass, java_lang_invoke_MethodHandleNatives, Pre ) \
167 do_klass(LambdaForm_klass, java_lang_invoke_LambdaForm, Opt ) \
168 do_klass(MethodType_klass, java_lang_invoke_MethodType, Pre ) \
169 do_klass(BootstrapMethodError_klass, java_lang_BootstrapMethodError, Pre ) \
170 do_klass(CallSite_klass, java_lang_invoke_CallSite, Pre ) \
171 do_klass(Context_klass, java_lang_invoke_MethodHandleNatives_CallSiteContext, Pre ) \
172 do_klass(ConstantCallSite_klass, java_lang_invoke_ConstantCallSite, Pre ) \
173 do_klass(MutableCallSite_klass, java_lang_invoke_MutableCallSite, Pre ) \
174 do_klass(VolatileCallSite_klass, java_lang_invoke_VolatileCallSite, Pre ) \
175 /* Note: MethodHandle must be first, and VolatileCallSite last in group */ \
176 \
177 do_klass(AssertionStatusDirectives_klass, java_lang_AssertionStatusDirectives, Pre ) \
178 do_klass(StringBuffer_klass, java_lang_StringBuffer, Pre ) \
179 do_klass(StringBuilder_klass, java_lang_StringBuilder, Pre ) \
180 do_klass(internal_Unsafe_klass, jdk_internal_misc_Unsafe, Pre ) \
181 do_klass(module_Modules_klass, jdk_internal_module_Modules, Pre ) \
182 \
183 /* support for CDS */ \
184 do_klass(ByteArrayInputStream_klass, java_io_ByteArrayInputStream, Pre ) \
185 do_klass(File_klass, java_io_File, Pre ) \
186 do_klass(URL_klass, java_net_URL, Pre ) \
187 do_klass(Jar_Manifest_klass, java_util_jar_Manifest, Pre ) \
188 do_klass(jdk_internal_loader_ClassLoaders_AppClassLoader_klass, jdk_internal_loader_ClassLoaders_AppClassLoader, Pre ) \
189 do_klass(jdk_internal_loader_ClassLoaders_PlatformClassLoader_klass, jdk_internal_loader_ClassLoaders_PlatformClassLoader, Pre ) \
190 do_klass(CodeSource_klass, java_security_CodeSource, Pre ) \
191 do_klass(ParseUtil_klass, sun_net_www_ParseUtil, Pre ) \
192 \
193 do_klass(StackTraceElement_klass, java_lang_StackTraceElement, Opt ) \
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, Opt ) \
197 \
198 /* Stack Walking */ \
199 do_klass(StackWalker_klass, java_lang_StackWalker, Opt ) \
200 do_klass(AbstractStackWalker_klass, java_lang_StackStreamFactory_AbstractStackWalker, Opt ) \
201 do_klass(StackFrameInfo_klass, java_lang_StackFrameInfo, Opt ) \
202 do_klass(LiveStackFrameInfo_klass, java_lang_LiveStackFrameInfo, Opt ) \
203 \
204 /* Preload boxing klasses */ \
205 do_klass(Boolean_klass, java_lang_Boolean, Pre ) \
206 do_klass(Character_klass, java_lang_Character, Pre ) \
207 do_klass(Float_klass, java_lang_Float, Pre ) \
208 do_klass(Double_klass, java_lang_Double, Pre ) \
209 do_klass(Byte_klass, java_lang_Byte, Pre ) \
210 do_klass(Short_klass, java_lang_Short, Pre ) \
211 do_klass(Integer_klass, java_lang_Integer, Pre ) \
212 do_klass(Long_klass, java_lang_Long, Pre ) \
213 \
214 /* Extensions */ \
215 WK_KLASSES_DO_EXT(do_klass) \
216 /* JVMCI classes. These are loaded on-demand. */ \
217 JVMCI_WK_KLASSES_DO(do_klass) \
218 \
219 /*end*/
220
221
222 class SystemDictionary : AllStatic {
223 friend class VMStructs;
224 friend class SystemDictionaryHandles;
225 friend class SharedClassUtil;
226
227 public:
228 enum WKID {
229 NO_WKID = 0,
230
231 #define WK_KLASS_ENUM(name, symbol, ignore_o) WK_KLASS_ENUM_NAME(name), WK_KLASS_ENUM_NAME(symbol) = WK_KLASS_ENUM_NAME(name),
232 WK_KLASSES_DO(WK_KLASS_ENUM)
233 #undef WK_KLASS_ENUM
234
235 WKID_LIMIT,
236
237 #if INCLUDE_JVMCI
238 FIRST_JVMCI_WKID = WK_KLASS_ENUM_NAME(JVMCI_klass),
239 LAST_JVMCI_WKID = WK_KLASS_ENUM_NAME(Value_klass),
240 #endif
241
242 FIRST_WKID = NO_WKID + 1
243 };
244
245 enum InitOption {
246 Pre, // preloaded; error if not present
247
248 // Order is significant. Options before this point require resolve_or_fail.
249 // Options after this point will use resolve_or_null instead.
250
251 Opt, // preload tried; NULL if not present
252 #if INCLUDE_JVMCI
253 Jvmci, // preload tried; error if not present if JVMCI enabled
254 #endif
255 OPTION_LIMIT,
256 CEIL_LG_OPTION_LIMIT = 2 // OPTION_LIMIT <= (1<<CEIL_LG_OPTION_LIMIT)
257 };
258
259
260 // Returns a class with a given class name and class loader. Loads the
261 // class if needed. If not found a NoClassDefFoundError or a
262 // ClassNotFoundException is thrown, depending on the value on the
263 // throw_error flag. For most uses the throw_error argument should be set
264 // to true.
265
266 static Klass* resolve_or_fail(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS);
267 // Convenient call for null loader and protection domain.
268 static Klass* resolve_or_fail(Symbol* class_name, bool throw_error, TRAPS);
269 protected:
270 // handle error translation for resolve_or_null results
271 static Klass* handle_resolution_exception(Symbol* class_name, bool throw_error, Klass* klass, TRAPS);
272
273 public:
274
275 // Returns a class with a given class name and class loader.
276 // Loads the class if needed. If not found NULL is returned.
277 static Klass* resolve_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
278 // Version with null loader and protection domain
279 static Klass* resolve_or_null(Symbol* class_name, TRAPS);
280
281 // Resolve a superclass or superinterface. Called from ClassFileParser,
282 // parse_interfaces, resolve_instance_class_or_null, load_shared_class
283 // "child_name" is the class whose super class or interface is being resolved.
284 static Klass* resolve_super_or_fail(Symbol* child_name,
285 Symbol* class_name,
286 Handle class_loader,
287 Handle protection_domain,
288 bool is_superclass,
289 TRAPS);
290
291 // Parse new stream. This won't update the dictionary or
292 // class hierarchy, simply parse the stream. Used by JVMTI RedefineClasses.
293 // Also used by Unsafe_DefineAnonymousClass
294 static InstanceKlass* parse_stream(Symbol* class_name,
295 Handle class_loader,
296 Handle protection_domain,
297 ClassFileStream* st,
298 TRAPS) {
299 return parse_stream(class_name,
300 class_loader,
301 protection_domain,
302 st,
303 NULL, // host klass
304 NULL, // cp_patches
305 THREAD);
306 }
307 static InstanceKlass* parse_stream(Symbol* class_name,
308 Handle class_loader,
309 Handle protection_domain,
310 ClassFileStream* st,
311 const InstanceKlass* host_klass,
312 GrowableArray<Handle>* cp_patches,
313 TRAPS);
314
315 // Resolve from stream (called by jni_DefineClass and JVM_DefineClass)
316 static InstanceKlass* resolve_from_stream(Symbol* class_name,
317 Handle class_loader,
318 Handle protection_domain,
319 ClassFileStream* st,
320 TRAPS);
321
322 // Lookup an already loaded class. If not found NULL is returned.
323 static Klass* find(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
324
325 // Lookup an already loaded instance or array class.
326 // Do not make any queries to class loaders; consult only the cache.
327 // If not found NULL is returned.
328 static Klass* find_instance_or_array_klass(Symbol* class_name,
329 Handle class_loader,
330 Handle protection_domain,
331 TRAPS);
332
333 // Lookup an instance or array class that has already been loaded
334 // either into the given class loader, or else into another class
335 // loader that is constrained (via loader constraints) to produce
336 // a consistent class. Do not take protection domains into account.
337 // Do not make any queries to class loaders; consult only the cache.
338 // Return NULL if the class is not found.
339 //
340 // This function is a strict superset of find_instance_or_array_klass.
341 // This function (the unchecked version) makes a conservative prediction
342 // of the result of the checked version, assuming successful lookup.
343 // If both functions return non-null, they must return the same value.
344 // Also, the unchecked version may sometimes be non-null where the
345 // checked version is null. This can occur in several ways:
346 // 1. No query has yet been made to the class loader.
347 // 2. The class loader was queried, but chose not to delegate.
348 // 3. ClassLoader.checkPackageAccess rejected a proposed protection domain.
349 // 4. Loading was attempted, but there was a linkage error of some sort.
350 // In all of these cases, the loader constraints on this type are
351 // satisfied, and it is safe for classes in the given class loader
352 // to manipulate strongly-typed values of the found class, subject
353 // to local linkage and access checks.
354 static Klass* find_constrained_instance_or_array_klass(Symbol* class_name,
355 Handle class_loader,
356 TRAPS);
357
358 static void classes_do(MetaspaceClosure* it);
359 // Iterate over all methods in all klasses
360
361 static void methods_do(void f(Method*));
362
363 // Garbage collection support
364
365 // This method applies "blk->do_oop" to all the pointers to "system"
366 // classes and loaders.
367 static void always_strong_oops_do(OopClosure* blk);
368
369 // Unload (that is, break root links to) all unmarked classes and
370 // loaders. Returns "true" iff something was unloaded.
371 static bool do_unloading(BoolObjectClosure* is_alive,
372 GCTimer* gc_timer,
373 bool do_cleaning = true);
374
375 // Used by DumpSharedSpaces only to remove classes that failed verification
376 static void remove_classes_in_error_state();
377
378 static int calculate_systemdictionary_size(int loadedclasses);
379
380 // Applies "f->do_oop" to all root oops in the system dictionary.
381 static void oops_do(OopClosure* f);
382 static void roots_oops_do(OopClosure* strong, OopClosure* weak);
383
384 // System loader lock
385 static oop system_loader_lock() { return _system_loader_lock_obj; }
386
387 public:
388 // Sharing support.
389 static void reorder_dictionary_for_sharing() NOT_CDS_RETURN;
390 static void combine_shared_dictionaries();
391 static size_t count_bytes_for_buckets();
392 static size_t count_bytes_for_table();
393 static void copy_buckets(char* top, char* end);
394 static void copy_table(char* top, char* end);
395 static void set_shared_dictionary(HashtableBucket<mtClass>* t, int length,
396 int number_of_entries);
397 // Printing
398 static void print() { return print_on(tty); }
399 static void print_on(outputStream* st);
400 static void print_shared(outputStream* st);
401 static void dump(outputStream* st, bool verbose);
402
403 // Monotonically increasing counter which grows as classes are
404 // loaded or modifications such as hot-swapping or setting/removing
405 // of breakpoints are performed
406 static inline int number_of_modifications() { assert_locked_or_safepoint(Compile_lock); return _number_of_modifications; }
407 // Needed by evolution and breakpoint code
408 static inline void notice_modification() { assert_locked_or_safepoint(Compile_lock); ++_number_of_modifications; }
409
410 // Verification
411 static void verify();
412
413 // Initialization
414 static void initialize(TRAPS);
415
416 // Checked fast access to commonly used classes - mostly preloaded
417 static InstanceKlass* check_klass(InstanceKlass* k) {
418 assert(k != NULL, "klass not loaded");
419 return k;
420 }
421
422 static InstanceKlass* check_klass_Pre(InstanceKlass* k) { return check_klass(k); }
423 static InstanceKlass* check_klass_Opt(InstanceKlass* k) { return k; }
424
425 JVMCI_ONLY(static InstanceKlass* check_klass_Jvmci(InstanceKlass* k) { return k; })
426
427 static bool initialize_wk_klass(WKID id, int init_opt, TRAPS);
428 static void initialize_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS);
429 static void initialize_wk_klasses_through(WKID end_id, WKID &start_id, TRAPS) {
430 int limit = (int)end_id + 1;
431 initialize_wk_klasses_until((WKID) limit, start_id, THREAD);
432 }
433
434 public:
435 #define WK_KLASS_DECLARE(name, symbol, option) \
436 static InstanceKlass* name() { return check_klass_##option(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); } \
437 static InstanceKlass** name##_addr() { \
438 return &SystemDictionary::_well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]; \
439 }
440 WK_KLASSES_DO(WK_KLASS_DECLARE);
441 #undef WK_KLASS_DECLARE
442
443 static InstanceKlass* well_known_klass(WKID id) {
444 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
445 return _well_known_klasses[id];
446 }
447
448 static InstanceKlass** well_known_klass_addr(WKID id) {
449 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
450 return &_well_known_klasses[id];
451 }
452 static void well_known_klasses_do(MetaspaceClosure* it);
453
454 // Local definition for direct access to the private array:
455 #define WK_KLASS(name) _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]
456
457 static InstanceKlass* box_klass(BasicType t) {
458 assert((uint)t < T_VOID+1, "range check");
459 return check_klass(_box_klasses[t]);
460 }
461 static BasicType box_klass_type(Klass* k); // inverse of box_klass
462
463 // methods returning lazily loaded klasses
464 // The corresponding method to load the class must be called before calling them.
465 static InstanceKlass* abstract_ownable_synchronizer_klass() { return check_klass(_abstract_ownable_synchronizer_klass); }
466
467 static void load_abstract_ownable_synchronizer_klass(TRAPS);
468
469 protected:
470 // Returns the class loader data to be used when looking up/updating the
471 // system dictionary.
472 static ClassLoaderData *class_loader_data(Handle class_loader) {
473 return ClassLoaderData::class_loader_data(class_loader());
474 }
475
476 public:
477 // Tells whether ClassLoader.checkPackageAccess is present
478 static bool has_checkPackageAccess() { return _has_checkPackageAccess; }
479
480 static bool Parameter_klass_loaded() { return WK_KLASS(reflect_Parameter_klass) != NULL; }
481 static bool Class_klass_loaded() { return WK_KLASS(Class_klass) != NULL; }
482 static bool Cloneable_klass_loaded() { return WK_KLASS(Cloneable_klass) != NULL; }
483 static bool Object_klass_loaded() { return WK_KLASS(Object_klass) != NULL; }
484 static bool ClassLoader_klass_loaded() { return WK_KLASS(ClassLoader_klass) != NULL; }
485
486 // Returns java system loader
487 static oop java_system_loader();
488
489 // Returns java platform loader
490 static oop java_platform_loader();
491
492 // Compute the java system and platform loaders
493 static void compute_java_loaders(TRAPS);
494
495 // Register a new class loader
496 static ClassLoaderData* register_loader(Handle class_loader, TRAPS);
497 protected:
498 // Mirrors for primitive classes (created eagerly)
499 static oop check_mirror(oop m) {
500 assert(m != NULL, "mirror not initialized");
501 return m;
502 }
503
504 public:
505 // Note: java_lang_Class::primitive_type is the inverse of java_mirror
506
507 // Check class loader constraints
508 static bool add_loader_constraint(Symbol* name, Handle loader1,
509 Handle loader2, TRAPS);
510 static Symbol* check_signature_loaders(Symbol* signature, Handle loader1,
511 Handle loader2, bool is_method, TRAPS);
512
513 // JSR 292
514 // find a java.lang.invoke.MethodHandle.invoke* method for a given signature
515 // (asks Java to compute it if necessary, except in a compiler thread)
516 static methodHandle find_method_handle_invoker(Klass* klass,
517 Symbol* name,
518 Symbol* signature,
519 Klass* accessing_klass,
520 Handle *appendix_result,
521 Handle *method_type_result,
522 TRAPS);
523 // for a given signature, find the internal MethodHandle method (linkTo* or invokeBasic)
524 // (does not ask Java, since this is a low-level intrinsic defined by the JVM)
525 static methodHandle find_method_handle_intrinsic(vmIntrinsics::ID iid,
526 Symbol* signature,
527 TRAPS);
528
529 // compute java_mirror (java.lang.Class instance) for a type ("I", "[[B", "LFoo;", etc.)
530 // Either the accessing_klass or the CL/PD can be non-null, but not both.
531 static Handle find_java_mirror_for_type(Symbol* signature,
532 Klass* accessing_klass,
533 Handle class_loader,
534 Handle protection_domain,
535 SignatureStream::FailureMode failure_mode,
536 TRAPS);
537 static Handle find_java_mirror_for_type(Symbol* signature,
538 Klass* accessing_klass,
539 SignatureStream::FailureMode failure_mode,
540 TRAPS) {
541 // callee will fill in CL/PD from AK, if they are needed
542 return find_java_mirror_for_type(signature, accessing_klass, Handle(), Handle(),
543 failure_mode, THREAD);
544 }
545
546
547 // fast short-cut for the one-character case:
548 static oop find_java_mirror_for_type(char signature_char);
549
550 // find a java.lang.invoke.MethodType object for a given signature
551 // (asks Java to compute it if necessary, except in a compiler thread)
552 static Handle find_method_handle_type(Symbol* signature,
553 Klass* accessing_klass,
554 TRAPS);
555
556 // find a java.lang.Class object for a given signature
557 static Handle find_field_handle_type(Symbol* signature,
558 Klass* accessing_klass,
559 TRAPS);
560
561 // ask Java to compute a java.lang.invoke.MethodHandle object for a given CP entry
562 static Handle link_method_handle_constant(Klass* caller,
563 int ref_kind, //e.g., JVM_REF_invokeVirtual
564 Klass* callee,
565 Symbol* name,
566 Symbol* signature,
567 TRAPS);
568
569 // ask Java to compute a constant by invoking a BSM given a Dynamic_info CP entry
570 static Handle link_dynamic_constant(Klass* caller,
571 int condy_index,
572 Handle bootstrap_specifier,
573 Symbol* name,
574 Symbol* type,
575 TRAPS);
576
577 // ask Java to create a dynamic call site, while linking an invokedynamic op
578 static methodHandle find_dynamic_call_site_invoker(Klass* caller,
579 int indy_index,
580 Handle bootstrap_method,
581 Symbol* name,
582 Symbol* type,
583 Handle *appendix_result,
584 Handle *method_type_result,
585 TRAPS);
586
587 // Utility for printing loader "name" as part of tracing constraints
588 static const char* loader_name(const oop loader);
589 static const char* loader_name(const ClassLoaderData* loader_data);
590
591 // Record the error when the first attempt to resolve a reference from a constant
592 // pool entry to a class fails.
593 static void add_resolution_error(const constantPoolHandle& pool, int which, Symbol* error,
594 Symbol* message);
595 static void delete_resolution_error(ConstantPool* pool);
596 static Symbol* find_resolution_error(const constantPoolHandle& pool, int which,
597 Symbol** message);
598
599
600 static ProtectionDomainCacheEntry* cache_get(Handle protection_domain);
601
602 protected:
603
604 enum Constants {
605 _loader_constraint_size = 107, // number of entries in constraint table
606 _resolution_error_size = 107, // number of entries in resolution error table
607 _invoke_method_size = 139, // number of entries in invoke method table
608 _shared_dictionary_size = 1009, // number of entries in shared dictionary
609 _placeholder_table_size = 1009 // number of entries in hash table for placeholders
610 };
611
612
613 // Static tables owned by the SystemDictionary
614
615 // Hashtable holding placeholders for classes being loaded.
616 static PlaceholderTable* _placeholders;
617
618 // Hashtable holding classes from the shared archive.
619 static Dictionary* _shared_dictionary;
620
621 // Monotonically increasing counter which grows with
622 // loading classes as well as hot-swapping and breakpoint setting
623 // and removal.
624 static int _number_of_modifications;
625
626 // Lock object for system class loader
627 static oop _system_loader_lock_obj;
628
629 // Constraints on class loaders
630 static LoaderConstraintTable* _loader_constraints;
631
632 // Resolution errors
633 static ResolutionErrorTable* _resolution_errors;
634
635 // Invoke methods (JSR 292)
636 static SymbolPropertyTable* _invoke_method_table;
637
638 // ProtectionDomain cache
639 static ProtectionDomainCacheTable* _pd_cache_table;
640
641 protected:
642 static void validate_protection_domain(InstanceKlass* klass,
643 Handle class_loader,
644 Handle protection_domain, TRAPS);
645
646 friend class VM_PopulateDumpSharedSpace;
647 friend class TraversePlaceholdersClosure;
648 static Dictionary* shared_dictionary() { return _shared_dictionary; }
649 static PlaceholderTable* placeholders() { return _placeholders; }
650 static LoaderConstraintTable* constraints() { return _loader_constraints; }
651 static ResolutionErrorTable* resolution_errors() { return _resolution_errors; }
652 static SymbolPropertyTable* invoke_method_table() { return _invoke_method_table; }
653
654 // Basic loading operations
655 static Klass* resolve_instance_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
656 static Klass* resolve_array_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
657 static InstanceKlass* handle_parallel_super_load(Symbol* class_name, Symbol* supername, Handle class_loader, Handle protection_domain, Handle lockObject, TRAPS);
658 // Wait on SystemDictionary_lock; unlocks lockObject before
659 // waiting; relocks lockObject with correct recursion count
660 // after waiting, but before reentering SystemDictionary_lock
661 // to preserve lock order semantics.
662 static void double_lock_wait(Handle lockObject, TRAPS);
663 static void define_instance_class(InstanceKlass* k, TRAPS);
664 static InstanceKlass* find_or_define_instance_class(Symbol* class_name,
665 Handle class_loader,
666 InstanceKlass* k, TRAPS);
667 static bool is_shared_class_visible(Symbol* class_name, InstanceKlass* ik,
668 Handle class_loader, TRAPS);
669 static InstanceKlass* load_shared_class(InstanceKlass* ik,
670 Handle class_loader,
671 Handle protection_domain,
672 TRAPS);
673 static InstanceKlass* load_instance_class(Symbol* class_name, Handle class_loader, TRAPS);
674 static Handle compute_loader_lock_object(Handle class_loader, TRAPS);
675 static void check_loader_lock_contention(Handle loader_lock, TRAPS);
676 static bool is_parallelCapable(Handle class_loader);
677 static bool is_parallelDefine(Handle class_loader);
678
679 public:
680 static InstanceKlass* load_shared_class(Symbol* class_name,
681 Handle class_loader,
682 TRAPS);
683 static bool is_system_class_loader(oop class_loader);
684 static bool is_platform_class_loader(oop class_loader);
685 static void clear_invoke_method_table();
686
687 // Returns TRUE if the method is a non-public member of class java.lang.Object.
688 static bool is_nonpublic_Object_method(Method* m) {
689 assert(m != NULL, "Unexpected NULL Method*");
690 return !m->is_public() && m->method_holder() == SystemDictionary::Object_klass();
691 }
692
693 protected:
694 static InstanceKlass* find_shared_class(Symbol* class_name);
695
696 // Setup link to hierarchy
697 static void add_to_hierarchy(InstanceKlass* k, TRAPS);
698
699 // Basic find on loaded classes
700 static InstanceKlass* find_class(unsigned int hash,
701 Symbol* name, Dictionary* dictionary);
702 static InstanceKlass* find_class(Symbol* class_name, ClassLoaderData* loader_data);
703
704 // Basic find on classes in the midst of being loaded
705 static Symbol* find_placeholder(Symbol* name, ClassLoaderData* loader_data);
706
707 // Add a placeholder for a class being loaded
708 static void add_placeholder(int index,
709 Symbol* class_name,
710 ClassLoaderData* loader_data);
711 static void remove_placeholder(int index,
712 Symbol* class_name,
713 ClassLoaderData* loader_data);
714
715 // Performs cleanups after resolve_super_or_fail. This typically needs
716 // to be called on failure.
717 // Won't throw, but can block.
718 static void resolution_cleanups(Symbol* class_name,
719 ClassLoaderData* loader_data,
720 TRAPS);
721
722 // Initialization
723 static void initialize_preloaded_classes(TRAPS);
724
725 // Class loader constraints
726 static void check_constraints(unsigned int hash,
727 InstanceKlass* k, Handle loader,
728 bool defining, TRAPS);
729 static void update_dictionary(unsigned int d_hash,
730 int p_index, unsigned int p_hash,
731 InstanceKlass* k, Handle loader,
732 TRAPS);
733
734 // Variables holding commonly used klasses (preloaded)
735 static InstanceKlass* _well_known_klasses[];
736
737 // Lazily loaded klasses
738 static InstanceKlass* volatile _abstract_ownable_synchronizer_klass;
739
740 // table of box klasses (int_klass, etc.)
741 static InstanceKlass* _box_klasses[T_VOID+1];
742
743 static oop _java_system_loader;
744 static oop _java_platform_loader;
745
746 static bool _has_checkPackageAccess;
747 };
748
749 #endif // SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP