1 /*
2 * Copyright (c) 1997, 2017, 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_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 "utilities/hashtable.hpp"
36 #include "utilities/hashtable.inline.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
88 // Certain classes are preloaded, such as java.lang.Object and java.lang.String.
89 // They are all "well-known", in the sense that no class loader is allowed
90 // to provide a different definition.
91 //
92 // These klasses must all have names defined in vmSymbols.
93
94 #define WK_KLASS_ENUM_NAME(kname) kname##_knum
95
96 // Each well-known class has a short klass name (like object_klass),
97 // a vmSymbol name (like java_lang_Object), and a flag word
98 // that makes some minor distinctions, like whether the klass
99 // is preloaded, optional, release-specific, etc.
100 // The order of these definitions is significant; it is the order in which
101 // preloading is actually performed by initialize_preloaded_classes.
102
103 #define WK_KLASSES_DO(do_klass) \
104 /* well-known classes */ \
105 do_klass(Object_klass, java_lang_Object, Pre ) \
106 do_klass(String_klass, java_lang_String, Pre ) \
107 do_klass(Class_klass, java_lang_Class, Pre ) \
108 do_klass(Cloneable_klass, java_lang_Cloneable, Pre ) \
109 do_klass(ClassLoader_klass, java_lang_ClassLoader, Pre ) \
110 do_klass(Serializable_klass, java_io_Serializable, Pre ) \
111 do_klass(System_klass, java_lang_System, Pre ) \
112 do_klass(Throwable_klass, java_lang_Throwable, Pre ) \
113 do_klass(Error_klass, java_lang_Error, Pre ) \
114 do_klass(ThreadDeath_klass, java_lang_ThreadDeath, Pre ) \
115 do_klass(Exception_klass, java_lang_Exception, Pre ) \
116 do_klass(RuntimeException_klass, java_lang_RuntimeException, Pre ) \
117 do_klass(SecurityManager_klass, java_lang_SecurityManager, Pre ) \
118 do_klass(ProtectionDomain_klass, java_security_ProtectionDomain, Pre ) \
119 do_klass(AccessControlContext_klass, java_security_AccessControlContext, Pre ) \
120 do_klass(SecureClassLoader_klass, java_security_SecureClassLoader, Pre ) \
121 do_klass(ClassNotFoundException_klass, java_lang_ClassNotFoundException, Pre ) \
122 do_klass(NoClassDefFoundError_klass, java_lang_NoClassDefFoundError, Pre ) \
123 do_klass(LinkageError_klass, java_lang_LinkageError, Pre ) \
124 do_klass(ClassCastException_klass, java_lang_ClassCastException, Pre ) \
125 do_klass(ArrayStoreException_klass, java_lang_ArrayStoreException, Pre ) \
126 do_klass(VirtualMachineError_klass, java_lang_VirtualMachineError, Pre ) \
127 do_klass(OutOfMemoryError_klass, java_lang_OutOfMemoryError, Pre ) \
128 do_klass(StackOverflowError_klass, java_lang_StackOverflowError, Pre ) \
129 do_klass(IllegalMonitorStateException_klass, java_lang_IllegalMonitorStateException, Pre ) \
130 do_klass(Reference_klass, java_lang_ref_Reference, Pre ) \
131 \
132 /* Preload ref klasses and set reference types */ \
133 do_klass(SoftReference_klass, java_lang_ref_SoftReference, Pre ) \
134 do_klass(WeakReference_klass, java_lang_ref_WeakReference, Pre ) \
135 do_klass(FinalReference_klass, java_lang_ref_FinalReference, Pre ) \
136 do_klass(PhantomReference_klass, java_lang_ref_PhantomReference, Pre ) \
137 do_klass(Finalizer_klass, java_lang_ref_Finalizer, Pre ) \
138 \
139 do_klass(Thread_klass, java_lang_Thread, Pre ) \
140 do_klass(ThreadGroup_klass, java_lang_ThreadGroup, Pre ) \
141 do_klass(Properties_klass, java_util_Properties, Pre ) \
142 do_klass(Module_klass, java_lang_Module, Pre ) \
143 do_klass(reflect_AccessibleObject_klass, java_lang_reflect_AccessibleObject, Pre ) \
144 do_klass(reflect_Field_klass, java_lang_reflect_Field, Pre ) \
145 do_klass(reflect_Parameter_klass, java_lang_reflect_Parameter, Opt ) \
146 do_klass(reflect_Method_klass, java_lang_reflect_Method, Pre ) \
147 do_klass(reflect_Constructor_klass, java_lang_reflect_Constructor, Pre ) \
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, Opt ) \
152 do_klass(reflect_MethodAccessorImpl_klass, reflect_MethodAccessorImpl, Pre ) \
153 do_klass(reflect_ConstructorAccessorImpl_klass, reflect_ConstructorAccessorImpl, Pre ) \
154 do_klass(reflect_DelegatingClassLoader_klass, reflect_DelegatingClassLoader, Opt ) \
155 do_klass(reflect_ConstantPool_klass, reflect_ConstantPool, Opt ) \
156 do_klass(reflect_UnsafeStaticFieldAccessorImpl_klass, reflect_UnsafeStaticFieldAccessorImpl, Opt ) \
157 do_klass(reflect_CallerSensitive_klass, reflect_CallerSensitive, Opt ) \
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, Opt ) \
161 do_klass(MethodHandle_klass, java_lang_invoke_MethodHandle, Pre ) \
162 do_klass(VarHandle_klass, java_lang_invoke_VarHandle, Pre ) \
163 do_klass(MemberName_klass, java_lang_invoke_MemberName, Pre ) \
164 do_klass(ResolvedMethodName_klass, java_lang_invoke_ResolvedMethodName, Pre ) \
165 do_klass(MethodHandleNatives_klass, java_lang_invoke_MethodHandleNatives, Pre ) \
166 do_klass(LambdaForm_klass, java_lang_invoke_LambdaForm, Opt ) \
167 do_klass(MethodType_klass, java_lang_invoke_MethodType, Pre ) \
168 do_klass(BootstrapMethodError_klass, java_lang_BootstrapMethodError, Pre ) \
169 do_klass(CallSite_klass, java_lang_invoke_CallSite, Pre ) \
170 do_klass(Context_klass, java_lang_invoke_MethodHandleNatives_CallSiteContext, Pre ) \
171 do_klass(ConstantCallSite_klass, java_lang_invoke_ConstantCallSite, Pre ) \
172 do_klass(MutableCallSite_klass, java_lang_invoke_MutableCallSite, Pre ) \
173 do_klass(VolatileCallSite_klass, java_lang_invoke_VolatileCallSite, Pre ) \
174 /* Note: MethodHandle must be first, and VolatileCallSite last in group */ \
175 \
176 do_klass(StringBuffer_klass, java_lang_StringBuffer, Pre ) \
177 do_klass(StringBuilder_klass, java_lang_StringBuilder, Pre ) \
178 do_klass(internal_Unsafe_klass, jdk_internal_misc_Unsafe, Pre ) \
179 do_klass(module_Modules_klass, jdk_internal_module_Modules, Pre ) \
180 \
181 /* support for CDS */ \
182 do_klass(ByteArrayInputStream_klass, java_io_ByteArrayInputStream, Pre ) \
183 do_klass(File_klass, java_io_File, Pre ) \
184 do_klass(URL_klass, java_net_URL, Pre ) \
185 do_klass(Jar_Manifest_klass, java_util_jar_Manifest, Pre ) \
186 do_klass(jdk_internal_loader_ClassLoaders_AppClassLoader_klass, jdk_internal_loader_ClassLoaders_AppClassLoader, Pre ) \
187 do_klass(jdk_internal_loader_ClassLoaders_PlatformClassLoader_klass, jdk_internal_loader_ClassLoaders_PlatformClassLoader, Pre ) \
188 do_klass(CodeSource_klass, java_security_CodeSource, Pre ) \
189 do_klass(ParseUtil_klass, sun_net_www_ParseUtil, Pre ) \
190 \
191 /* support for valhalla "shady" value type bytecode transformer */ \
192 do_klass(Valhalla_MVT1_0_klass, valhalla_shady_MVT1_0, MVTClasses ) \
193 \
194 do_klass(StackTraceElement_klass, java_lang_StackTraceElement, Opt ) \
195 \
196 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \
197 do_klass(nio_Buffer_klass, java_nio_Buffer, Opt ) \
198 \
199 /* Stack Walking */ \
200 do_klass(StackWalker_klass, java_lang_StackWalker, Opt ) \
201 do_klass(AbstractStackWalker_klass, java_lang_StackStreamFactory_AbstractStackWalker, Opt ) \
202 do_klass(StackFrameInfo_klass, java_lang_StackFrameInfo, Opt ) \
203 do_klass(LiveStackFrameInfo_klass, java_lang_LiveStackFrameInfo, Opt ) \
204 \
205 /* Preload boxing klasses */ \
206 do_klass(Boolean_klass, java_lang_Boolean, Pre ) \
207 do_klass(Character_klass, java_lang_Character, Pre ) \
208 do_klass(Float_klass, java_lang_Float, Pre ) \
209 do_klass(Double_klass, java_lang_Double, Pre ) \
210 do_klass(Byte_klass, java_lang_Byte, Pre ) \
211 do_klass(Short_klass, java_lang_Short, Pre ) \
212 do_klass(Integer_klass, java_lang_Integer, Pre ) \
213 do_klass(Long_klass, java_lang_Long, Pre ) \
214 \
215 do_klass(___Value_klass, java_lang____Value, ValhallaClasses ) \
216 \
217 /* Extensions */ \
218 WK_KLASSES_DO_EXT(do_klass) \
219 /* JVMCI classes. These are loaded on-demand. */ \
220 JVMCI_WK_KLASSES_DO(do_klass) \
221 \
222 /*end*/
223
224
225 class SystemDictionary : AllStatic {
226 friend class VMStructs;
227 friend class SystemDictionaryHandles;
228 friend class SharedClassUtil;
229
230 public:
231 enum WKID {
232 NO_WKID = 0,
233
234 #define WK_KLASS_ENUM(name, symbol, ignore_o) WK_KLASS_ENUM_NAME(name), WK_KLASS_ENUM_NAME(symbol) = WK_KLASS_ENUM_NAME(name),
235 WK_KLASSES_DO(WK_KLASS_ENUM)
236 #undef WK_KLASS_ENUM
237
238 WKID_LIMIT,
239
240 #if INCLUDE_JVMCI
241 FIRST_JVMCI_WKID = WK_KLASS_ENUM_NAME(JVMCI_klass),
242 LAST_JVMCI_WKID = WK_KLASS_ENUM_NAME(Value_klass),
243 #endif
244
245 FIRST_WKID = NO_WKID + 1
246 };
247
248 enum InitOption {
249 Pre, // preloaded; error if not present
250
251 // Order is significant. Options before this point require resolve_or_fail.
252 // Options after this point will use resolve_or_null instead.
253
254 Opt, // preload tried; NULL if not present
255 #if INCLUDE_JVMCI
256 Jvmci, // preload tried; error if not present if JVMCI enabled
257 #endif
258 ValhallaClasses, // loaded if Valhalla enabled
259 MVTClasses, // loaded if MVT enabled
260 OPTION_LIMIT,
261 CEIL_LG_OPTION_LIMIT = 3 // OPTION_LIMIT <= (1<<CEIL_LG_OPTION_LIMIT)
262 };
263
264
265 // Returns a class with a given class name and class loader. Loads the
266 // class if needed. If not found a NoClassDefFoundError or a
267 // ClassNotFoundException is thrown, depending on the value on the
268 // throw_error flag. For most uses the throw_error argument should be set
269 // to true.
270
271 static Klass* resolve_or_fail(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS);
272 // Convenient call for null loader and protection domain.
273 static Klass* resolve_or_fail(Symbol* class_name, bool throw_error, TRAPS);
274 protected:
275 // handle error translation for resolve_or_null results
276 static Klass* handle_resolution_exception(Symbol* class_name, bool throw_error, Klass* klass, TRAPS);
277
278 public:
279
280 // Returns a class with a given class name and class loader.
281 // Loads the class if needed. If not found NULL is returned.
282 static Klass* resolve_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
283 // Version with null loader and protection domain
284 static Klass* resolve_or_null(Symbol* class_name, TRAPS);
285
286 // Resolve a superclass or superinterface. Called from ClassFileParser,
287 // parse_interfaces, resolve_instance_class_or_null, load_shared_class
288 // "child_name" is the class whose super class or interface is being resolved.
289 static Klass* resolve_super_or_fail(Symbol* child_name,
290 Symbol* class_name,
291 Handle class_loader,
292 Handle protection_domain,
293 bool is_superclass,
294 TRAPS);
295
296 // Parse new stream. This won't update the dictionary or
297 // class hierarchy, simply parse the stream. Used by JVMTI RedefineClasses.
298 // Also used by Unsafe_DefineAnonymousClass
299 static InstanceKlass* parse_stream(Symbol* class_name,
300 Handle class_loader,
301 Handle protection_domain,
302 ClassFileStream* st,
303 TRAPS) {
304 return parse_stream(class_name,
305 class_loader,
306 protection_domain,
307 st,
308 NULL, // host klass
309 NULL, // cp_patches
310 THREAD);
311 }
312 static InstanceKlass* parse_stream(Symbol* class_name,
313 Handle class_loader,
314 Handle protection_domain,
315 ClassFileStream* st,
316 const InstanceKlass* host_klass,
317 GrowableArray<Handle>* cp_patches,
318 TRAPS);
319
320 // Resolve from stream (called by jni_DefineClass and JVM_DefineClass)
321 static InstanceKlass* resolve_from_stream(Symbol* class_name,
322 Handle class_loader,
323 Handle protection_domain,
324 ClassFileStream* st,
325 TRAPS);
326
327 // Lookup an already loaded class. If not found NULL is returned.
328 static Klass* find(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
329
330 // Lookup an already loaded instance or array class.
331 // Do not make any queries to class loaders; consult only the cache.
332 // If not found NULL is returned.
333 static Klass* find_instance_or_array_klass(Symbol* class_name,
334 Handle class_loader,
335 Handle protection_domain,
336 TRAPS);
337
338 // Lookup an instance or array class that has already been loaded
339 // either into the given class loader, or else into another class
340 // loader that is constrained (via loader constraints) to produce
341 // a consistent class. Do not take protection domains into account.
342 // Do not make any queries to class loaders; consult only the cache.
343 // Return NULL if the class is not found.
344 //
345 // This function is a strict superset of find_instance_or_array_klass.
346 // This function (the unchecked version) makes a conservative prediction
347 // of the result of the checked version, assuming successful lookup.
348 // If both functions return non-null, they must return the same value.
349 // Also, the unchecked version may sometimes be non-null where the
350 // checked version is null. This can occur in several ways:
351 // 1. No query has yet been made to the class loader.
352 // 2. The class loader was queried, but chose not to delegate.
353 // 3. ClassLoader.checkPackageAccess rejected a proposed protection domain.
354 // 4. Loading was attempted, but there was a linkage error of some sort.
355 // In all of these cases, the loader constraints on this type are
356 // satisfied, and it is safe for classes in the given class loader
357 // to manipulate strongly-typed values of the found class, subject
358 // to local linkage and access checks.
359 static Klass* find_constrained_instance_or_array_klass(Symbol* class_name,
360 Handle class_loader,
361 TRAPS);
362
363 static void classes_do(MetaspaceClosure* it);
364 // Iterate over all methods in all klasses
365
366 static void methods_do(void f(Method*));
367
368 // Garbage collection support
369
370 // This method applies "blk->do_oop" to all the pointers to "system"
371 // classes and loaders.
372 static void always_strong_oops_do(OopClosure* blk);
373
374 // Unload (that is, break root links to) all unmarked classes and
375 // loaders. Returns "true" iff something was unloaded.
376 static bool do_unloading(BoolObjectClosure* is_alive,
377 GCTimer* gc_timer,
378 bool do_cleaning = true);
379
380 // Used by DumpSharedSpaces only to remove classes that failed verification
381 static void remove_classes_in_error_state();
382
383 static int calculate_systemdictionary_size(int loadedclasses);
384
385 // Applies "f->do_oop" to all root oops in the system dictionary.
386 static void oops_do(OopClosure* f);
387 static void roots_oops_do(OopClosure* strong, OopClosure* weak);
388
389 // System loader lock
390 static oop system_loader_lock() { return _system_loader_lock_obj; }
391
392 public:
393 // Sharing support.
394 static void reorder_dictionary_for_sharing();
395 static size_t count_bytes_for_buckets();
396 static size_t count_bytes_for_table();
397 static void copy_buckets(char* top, char* end);
398 static void copy_table(char* top, char* end);
399 static void set_shared_dictionary(HashtableBucket<mtClass>* t, int length,
400 int number_of_entries);
401 // Printing
402 static void print() { return print_on(tty); }
403 static void print_on(outputStream* st);
404 static void print_shared(outputStream* st);
405 static void dump(outputStream* st, bool verbose);
406
407 // Monotonically increasing counter which grows as classes are
408 // loaded or modifications such as hot-swapping or setting/removing
409 // of breakpoints are performed
410 static inline int number_of_modifications() { assert_locked_or_safepoint(Compile_lock); return _number_of_modifications; }
411 // Needed by evolution and breakpoint code
412 static inline void notice_modification() { assert_locked_or_safepoint(Compile_lock); ++_number_of_modifications; }
413
414 // Verification
415 static void verify();
416
417 // Initialization
418 static void initialize(TRAPS);
419
420 // Checked fast access to commonly used classes - mostly preloaded
421 static InstanceKlass* check_klass(InstanceKlass* k) {
422 assert(k != NULL, "klass not loaded");
423 return k;
424 }
425
426 static InstanceKlass* check_klass_Pre(InstanceKlass* k) { return check_klass(k); }
427 static InstanceKlass* check_klass_Opt(InstanceKlass* k) { return k; }
428 static InstanceKlass* check_klass_ValhallaClasses(InstanceKlass* k) { return k; }
429 static InstanceKlass* check_klass_MVTClasses(InstanceKlass* k) { return k; }
430
431 JVMCI_ONLY(static InstanceKlass* check_klass_Jvmci(InstanceKlass* k) { return k; })
432
433 static bool initialize_wk_klass(WKID id, int init_opt, TRAPS);
434 static void initialize_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS);
435 static void initialize_wk_klasses_through(WKID end_id, WKID &start_id, TRAPS) {
436 int limit = (int)end_id + 1;
437 initialize_wk_klasses_until((WKID) limit, start_id, THREAD);
438 }
439
440 public:
441 #define WK_KLASS_DECLARE(name, symbol, option) \
442 static InstanceKlass* name() { return check_klass_##option(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); } \
443 static InstanceKlass** name##_addr() { \
444 return &SystemDictionary::_well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]; \
445 }
446 WK_KLASSES_DO(WK_KLASS_DECLARE);
447 #undef WK_KLASS_DECLARE
448
449 static InstanceKlass* well_known_klass(WKID id) {
450 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
451 return _well_known_klasses[id];
452 }
453
454 static InstanceKlass** well_known_klass_addr(WKID id) {
455 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
456 return &_well_known_klasses[id];
457 }
458 static void well_known_klasses_do(MetaspaceClosure* it);
459
460 // Local definition for direct access to the private array:
461 #define WK_KLASS(name) _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]
462
463 static InstanceKlass* box_klass(BasicType t) {
464 assert((uint)t < T_VOID+1, "range check");
465 return check_klass(_box_klasses[t]);
466 }
467 static BasicType box_klass_type(Klass* k); // inverse of box_klass
468
469 // methods returning lazily loaded klasses
470 // The corresponding method to load the class must be called before calling them.
471 static InstanceKlass* abstract_ownable_synchronizer_klass() { return check_klass(_abstract_ownable_synchronizer_klass); }
472
473 static void load_abstract_ownable_synchronizer_klass(TRAPS);
474
475 protected:
476 // Tells whether ClassLoader.loadClassInternal is present
477 static bool has_loadClassInternal() { return _has_loadClassInternal; }
478
479 // Returns the class loader data to be used when looking up/updating the
480 // system dictionary.
481 static ClassLoaderData *class_loader_data(Handle class_loader) {
482 return ClassLoaderData::class_loader_data(class_loader());
483 }
484
485 public:
486 // Tells whether ClassLoader.checkPackageAccess is present
487 static bool has_checkPackageAccess() { return _has_checkPackageAccess; }
488
489 static bool Parameter_klass_loaded() { return WK_KLASS(reflect_Parameter_klass) != NULL; }
490 static bool Class_klass_loaded() { return WK_KLASS(Class_klass) != NULL; }
491 static bool Cloneable_klass_loaded() { return WK_KLASS(Cloneable_klass) != NULL; }
492 static bool Object_klass_loaded() { return WK_KLASS(Object_klass) != NULL; }
493 static bool ClassLoader_klass_loaded() { return WK_KLASS(ClassLoader_klass) != NULL; }
494
495 // Returns default system loader
496 static oop java_system_loader();
497
498 // Compute the default system loader
499 static void compute_java_system_loader(TRAPS);
500
501 // Register a new class loader
502 static ClassLoaderData* register_loader(Handle class_loader, TRAPS);
503 protected:
504 // Mirrors for primitive classes (created eagerly)
505 static oop check_mirror(oop m) {
506 assert(m != NULL, "mirror not initialized");
507 return m;
508 }
509
510 public:
511 // Note: java_lang_Class::primitive_type is the inverse of java_mirror
512
513 // Check class loader constraints
514 static bool add_loader_constraint(Symbol* name, Handle loader1,
515 Handle loader2, TRAPS);
516 static Symbol* check_signature_loaders(Symbol* signature, Handle loader1,
517 Handle loader2, bool is_method, TRAPS);
518
519 // JSR 292
520 // find a java.lang.invoke.MethodHandle.invoke* method for a given signature
521 // (asks Java to compute it if necessary, except in a compiler thread)
522 static methodHandle find_method_handle_invoker(Klass* klass,
523 Symbol* name,
524 Symbol* signature,
525 Klass* accessing_klass,
526 Handle *appendix_result,
527 Handle *method_type_result,
528 TRAPS);
529 // for a given signature, find the internal MethodHandle method (linkTo* or invokeBasic)
530 // (does not ask Java, since this is a low-level intrinsic defined by the JVM)
531 static methodHandle find_method_handle_intrinsic(vmIntrinsics::ID iid,
532 Symbol* signature,
533 TRAPS);
534 // find a java.lang.invoke.MethodType object for a given signature
535 // (asks Java to compute it if necessary, except in a compiler thread)
536 static Handle find_method_handle_type(Symbol* signature,
537 Klass* accessing_klass,
538 TRAPS);
539
540 // ask Java to compute a java.lang.invoke.MethodHandle object for a given CP entry
541 static Handle link_method_handle_constant(Klass* caller,
542 int ref_kind, //e.g., JVM_REF_invokeVirtual
543 Klass* callee,
544 Symbol* name,
545 Symbol* signature,
546 TRAPS);
547
548 // ask Java to create a dynamic call site, while linking an invokedynamic op
549 static methodHandle find_dynamic_call_site_invoker(Klass* caller,
550 Handle bootstrap_method,
551 Symbol* name,
552 Symbol* type,
553 Handle *appendix_result,
554 Handle *method_type_result,
555 TRAPS);
556
557 // Utility for printing loader "name" as part of tracing constraints
558 static const char* loader_name(const oop loader);
559 static const char* loader_name(const ClassLoaderData* loader_data);
560
561 // Record the error when the first attempt to resolve a reference from a constant
562 // pool entry to a class fails.
563 static void add_resolution_error(const constantPoolHandle& pool, int which, Symbol* error,
564 Symbol* message);
565 static void delete_resolution_error(ConstantPool* pool);
566 static Symbol* find_resolution_error(const constantPoolHandle& pool, int which,
567 Symbol** message);
568
569
570 static ProtectionDomainCacheEntry* cache_get(Handle protection_domain);
571
572 protected:
573
574 enum Constants {
575 _loader_constraint_size = 107, // number of entries in constraint table
576 _resolution_error_size = 107, // number of entries in resolution error table
577 _invoke_method_size = 139, // number of entries in invoke method table
578 _shared_dictionary_size = 1009, // number of entries in shared dictionary
579 _placeholder_table_size = 1009 // number of entries in hash table for placeholders
580 };
581
582
583 // Static tables owned by the SystemDictionary
584
585 // Hashtable holding placeholders for classes being loaded.
586 static PlaceholderTable* _placeholders;
587
588 // Hashtable holding classes from the shared archive.
589 static Dictionary* _shared_dictionary;
590
591 // Monotonically increasing counter which grows with
592 // loading classes as well as hot-swapping and breakpoint setting
593 // and removal.
594 static int _number_of_modifications;
595
596 // Lock object for system class loader
597 static oop _system_loader_lock_obj;
598
599 // Constraints on class loaders
600 static LoaderConstraintTable* _loader_constraints;
601
602 // Resolution errors
603 static ResolutionErrorTable* _resolution_errors;
604
605 // Invoke methods (JSR 292)
606 static SymbolPropertyTable* _invoke_method_table;
607
608 // ProtectionDomain cache
609 static ProtectionDomainCacheTable* _pd_cache_table;
610
611 protected:
612 static void validate_protection_domain(InstanceKlass* klass,
613 Handle class_loader,
614 Handle protection_domain, TRAPS);
615
616 friend class VM_PopulateDumpSharedSpace;
617 friend class TraversePlaceholdersClosure;
618 static Dictionary* shared_dictionary() { return _shared_dictionary; }
619 static PlaceholderTable* placeholders() { return _placeholders; }
620 static LoaderConstraintTable* constraints() { return _loader_constraints; }
621 static ResolutionErrorTable* resolution_errors() { return _resolution_errors; }
622 static SymbolPropertyTable* invoke_method_table() { return _invoke_method_table; }
623
624 // Basic loading operations
625 static Klass* resolve_instance_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
626 static Klass* do_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 Klass* resolve_dvt_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
629 static InstanceKlass* handle_parallel_super_load(Symbol* class_name, Symbol* supername, Handle class_loader, Handle protection_domain, Handle lockObject, TRAPS);
630 // Wait on SystemDictionary_lock; unlocks lockObject before
631 // waiting; relocks lockObject with correct recursion count
632 // after waiting, but before reentering SystemDictionary_lock
633 // to preserve lock order semantics.
634 static void double_lock_wait(Handle lockObject, TRAPS);
635 static void define_instance_class(InstanceKlass* k, TRAPS);
636 static InstanceKlass* find_or_define_instance_class(Symbol* class_name,
637 Handle class_loader,
638 InstanceKlass* k, TRAPS);
639 static bool is_shared_class_visible(Symbol* class_name, InstanceKlass* ik,
640 Handle class_loader, TRAPS);
641 static InstanceKlass* load_shared_class(InstanceKlass* ik,
642 Handle class_loader,
643 Handle protection_domain,
644 TRAPS);
645 static InstanceKlass* load_instance_class(Symbol* class_name, Handle class_loader, TRAPS);
646 static Handle compute_loader_lock_object(Handle class_loader, TRAPS);
647 static void check_loader_lock_contention(Handle loader_lock, TRAPS);
648 static bool is_parallelCapable(Handle class_loader);
649 static bool is_parallelDefine(Handle class_loader);
650
651 public:
652 static InstanceKlass* load_shared_class(Symbol* class_name,
653 Handle class_loader,
654 TRAPS);
655 static bool is_system_class_loader(oop class_loader);
656 static bool is_platform_class_loader(oop class_loader);
657
658 protected:
659 static InstanceKlass* find_shared_class(Symbol* class_name);
660
661 // Setup link to hierarchy
662 static void add_to_hierarchy(InstanceKlass* k, TRAPS);
663
664 // We pass in the hashtable index so we can calculate it outside of
665 // the SystemDictionary_lock.
666
667 // Basic find on loaded classes
668 static InstanceKlass* find_class(int index, unsigned int hash,
669 Symbol* name, Dictionary* dictionary);
670 static InstanceKlass* find_class(Symbol* class_name, ClassLoaderData* loader_data);
671
672 // Basic find on classes in the midst of being loaded
673 static Symbol* find_placeholder(Symbol* name, ClassLoaderData* loader_data);
674
675 // Add a placeholder for a class being loaded
676 static void add_placeholder(int index,
677 Symbol* class_name,
678 ClassLoaderData* loader_data);
679 static void remove_placeholder(int index,
680 Symbol* class_name,
681 ClassLoaderData* loader_data);
682
683 // Performs cleanups after resolve_super_or_fail. This typically needs
684 // to be called on failure.
685 // Won't throw, but can block.
686 static void resolution_cleanups(Symbol* class_name,
687 ClassLoaderData* loader_data,
688 TRAPS);
689
690 // Initialization
691 static void initialize_preloaded_classes(TRAPS);
692
693 // Class loader constraints
694 static void check_constraints(int index, unsigned int hash,
695 InstanceKlass* k, Handle loader,
696 bool defining, TRAPS);
697 static void update_dictionary(int d_index, unsigned int d_hash,
698 int p_index, unsigned int p_hash,
699 InstanceKlass* k, Handle loader,
700 TRAPS);
701
702 // Variables holding commonly used klasses (preloaded)
703 static InstanceKlass* _well_known_klasses[];
704
705 // Lazily loaded klasses
706 static InstanceKlass* volatile _abstract_ownable_synchronizer_klass;
707
708 // table of box klasses (int_klass, etc.)
709 static InstanceKlass* _box_klasses[T_VOID+1];
710
711 static oop _java_system_loader;
712
713 static bool _has_loadClassInternal;
714 static bool _has_checkPackageAccess;
715 };
716
717 #endif // SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP