1 /*
2 * Copyright (c) 1997, 2013, 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.
18 *
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
21 * questions.
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23 */
24
25 #ifndef SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP
26 #define SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP
27
28 #include "classfile/classFileStream.hpp"
29 #include "classfile/classLoader.hpp"
30 #include "oops/objArrayOop.hpp"
31 #include "oops/symbol.hpp"
32 #include "runtime/java.hpp"
33 #include "runtime/reflectionUtils.hpp"
34 #include "utilities/hashtable.hpp"
35 #include "utilities/hashtable.inline.hpp"
36
37 // The system dictionary stores all loaded classes and maps:
38 //
39 // [class name,class loader] -> class i.e. [Symbol*,oop] -> klassOop
40 //
41 // Classes are loaded lazily. The default VM class loader is
42 // represented as NULL.
43
44 // The underlying data structure is an open hash table with a fixed number
45 // of buckets. During loading the loader object is locked, (for the VM loader
46 // a private lock object is used). Class loading can thus be done concurrently,
47 // but only by different loaders.
48 //
49 // During loading a placeholder (name, loader) is temporarily placed in
50 // a side data structure, and is used to detect ClassCircularityErrors
51 // and to perform verification during GC. A GC can occur in the midst
52 // of class loading, as we call out to Java, have to take locks, etc.
53 //
54 // When class loading is finished, a new entry is added to the system
55 // dictionary and the place holder is removed. Note that the protection
56 // domain field of the system dictionary has not yet been filled in when
57 // the "real" system dictionary entry is created.
58 //
59 // Clients of this class who are interested in finding if a class has
60 // been completely loaded -- not classes in the process of being loaded --
61 // can read the SystemDictionary unlocked. This is safe because
62 // - entries are only deleted at safepoints
63 // - readers cannot come to a safepoint while actively examining
64 // an entry (an entry cannot be deleted from under a reader)
65 // - entries must be fully formed before they are available to concurrent
66 // readers (we must ensure write ordering)
67 //
68 // Note that placeholders are deleted at any time, as they are removed
69 // when a class is completely loaded. Therefore, readers as well as writers
70 // of placeholders must hold the SystemDictionary_lock.
71 //
72
73 class Dictionary;
74 class PlaceholderTable;
75 class LoaderConstraintTable;
76 template <MEMFLAGS F> class HashtableBucket;
77 class ResolutionErrorTable;
78 class SymbolPropertyTable;
79
80 // Certain classes are preloaded, such as java.lang.Object and java.lang.String.
81 // They are all "well-known", in the sense that no class loader is allowed
82 // to provide a different definition.
83 //
84 // These klasses must all have names defined in vmSymbols.
85
86 #define WK_KLASS_ENUM_NAME(kname) kname##_knum
87
88 // Each well-known class has a short klass name (like object_klass),
89 // a vmSymbol name (like java_lang_Object), and a flag word
90 // that makes some minor distinctions, like whether the klass
91 // is preloaded, optional, release-specific, etc.
92 // The order of these definitions is significant; it is the order in which
93 // preloading is actually performed by initialize_preloaded_classes.
94
95 #define WK_KLASSES_DO(do_klass) \
96 /* well-known classes */ \
97 do_klass(Object_klass, java_lang_Object, Pre ) \
98 do_klass(String_klass, java_lang_String, Pre ) \
99 do_klass(Class_klass, java_lang_Class, Pre ) \
100 do_klass(Cloneable_klass, java_lang_Cloneable, Pre ) \
101 do_klass(ClassLoader_klass, java_lang_ClassLoader, Pre ) \
102 do_klass(Serializable_klass, java_io_Serializable, Pre ) \
103 do_klass(System_klass, java_lang_System, Pre ) \
104 do_klass(Throwable_klass, java_lang_Throwable, Pre ) \
105 do_klass(Error_klass, java_lang_Error, Pre ) \
106 do_klass(ThreadDeath_klass, java_lang_ThreadDeath, Pre ) \
107 do_klass(Exception_klass, java_lang_Exception, Pre ) \
108 do_klass(RuntimeException_klass, java_lang_RuntimeException, Pre ) \
109 do_klass(ProtectionDomain_klass, java_security_ProtectionDomain, Pre ) \
110 do_klass(AccessControlContext_klass, java_security_AccessControlContext, Pre ) \
111 do_klass(ClassNotFoundException_klass, java_lang_ClassNotFoundException, Pre ) \
112 do_klass(NoClassDefFoundError_klass, java_lang_NoClassDefFoundError, Pre ) \
113 do_klass(LinkageError_klass, java_lang_LinkageError, Pre ) \
114 do_klass(ClassCastException_klass, java_lang_ClassCastException, Pre ) \
115 do_klass(ArrayStoreException_klass, java_lang_ArrayStoreException, Pre ) \
116 do_klass(VirtualMachineError_klass, java_lang_VirtualMachineError, Pre ) \
117 do_klass(OutOfMemoryError_klass, java_lang_OutOfMemoryError, Pre ) \
118 do_klass(StackOverflowError_klass, java_lang_StackOverflowError, Pre ) \
119 do_klass(IllegalMonitorStateException_klass, java_lang_IllegalMonitorStateException, Pre ) \
120 do_klass(Reference_klass, java_lang_ref_Reference, Pre ) \
121 \
122 /* Preload ref klasses and set reference types */ \
123 do_klass(SoftReference_klass, java_lang_ref_SoftReference, Pre ) \
124 do_klass(WeakReference_klass, java_lang_ref_WeakReference, Pre ) \
125 do_klass(FinalReference_klass, java_lang_ref_FinalReference, Pre ) \
126 do_klass(PhantomReference_klass, java_lang_ref_PhantomReference, Pre ) \
127 do_klass(Finalizer_klass, java_lang_ref_Finalizer, Pre ) \
128 \
129 do_klass(Thread_klass, java_lang_Thread, Pre ) \
130 do_klass(ThreadGroup_klass, java_lang_ThreadGroup, Pre ) \
131 do_klass(Properties_klass, java_util_Properties, Pre ) \
132 do_klass(reflect_AccessibleObject_klass, java_lang_reflect_AccessibleObject, Pre ) \
133 do_klass(reflect_Field_klass, java_lang_reflect_Field, Pre ) \
134 do_klass(reflect_Method_klass, java_lang_reflect_Method, Pre ) \
135 do_klass(reflect_Constructor_klass, java_lang_reflect_Constructor, Pre ) \
136 \
137 /* NOTE: needed too early in bootstrapping process to have checks based on JDK version */ \
138 /* Universe::is_gte_jdk14x_version() is not set up by this point. */ \
139 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \
140 do_klass(reflect_MagicAccessorImpl_klass, sun_reflect_MagicAccessorImpl, Opt ) \
141 do_klass(reflect_MethodAccessorImpl_klass, sun_reflect_MethodAccessorImpl, Opt_Only_JDK14NewRef) \
142 do_klass(reflect_ConstructorAccessorImpl_klass, sun_reflect_ConstructorAccessorImpl, Opt_Only_JDK14NewRef) \
143 do_klass(reflect_DelegatingClassLoader_klass, sun_reflect_DelegatingClassLoader, Opt ) \
144 do_klass(reflect_ConstantPool_klass, sun_reflect_ConstantPool, Opt_Only_JDK15 ) \
145 do_klass(reflect_UnsafeStaticFieldAccessorImpl_klass, sun_reflect_UnsafeStaticFieldAccessorImpl, Opt_Only_JDK15 ) \
146 \
147 /* support for dynamic typing; it's OK if these are NULL in earlier JDKs */ \
148 do_klass(MethodHandle_klass, java_lang_invoke_MethodHandle, Pre_JSR292 ) \
149 do_klass(MemberName_klass, java_lang_invoke_MemberName, Pre_JSR292 ) \
150 do_klass(MethodHandleNatives_klass, java_lang_invoke_MethodHandleNatives, Pre_JSR292 ) \
151 do_klass(LambdaForm_klass, java_lang_invoke_LambdaForm, Opt ) \
152 do_klass(MethodType_klass, java_lang_invoke_MethodType, Pre_JSR292 ) \
153 do_klass(BootstrapMethodError_klass, java_lang_BootstrapMethodError, Pre_JSR292 ) \
154 do_klass(CallSite_klass, java_lang_invoke_CallSite, Pre_JSR292 ) \
155 do_klass(ConstantCallSite_klass, java_lang_invoke_ConstantCallSite, Pre_JSR292 ) \
156 do_klass(MutableCallSite_klass, java_lang_invoke_MutableCallSite, Pre_JSR292 ) \
157 do_klass(VolatileCallSite_klass, java_lang_invoke_VolatileCallSite, Pre_JSR292 ) \
158 /* Note: MethodHandle must be first, and VolatileCallSite last in group */ \
159 \
160 do_klass(StringBuffer_klass, java_lang_StringBuffer, Pre ) \
161 do_klass(StringBuilder_klass, java_lang_StringBuilder, Pre ) \
162 \
163 /* It's NULL in non-1.4 JDKs. */ \
164 do_klass(StackTraceElement_klass, java_lang_StackTraceElement, Opt ) \
165 /* Universe::is_gte_jdk14x_version() is not set up by this point. */ \
166 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \
167 do_klass(nio_Buffer_klass, java_nio_Buffer, Opt ) \
168 \
169 do_klass(PostVMInitHook_klass, sun_misc_PostVMInitHook, Opt ) \
170 \
171 /* Preload boxing klasses */ \
172 do_klass(Boolean_klass, java_lang_Boolean, Pre ) \
173 do_klass(Character_klass, java_lang_Character, Pre ) \
174 do_klass(Float_klass, java_lang_Float, Pre ) \
175 do_klass(Double_klass, java_lang_Double, Pre ) \
176 do_klass(Byte_klass, java_lang_Byte, Pre ) \
177 do_klass(Short_klass, java_lang_Short, Pre ) \
178 do_klass(Integer_klass, java_lang_Integer, Pre ) \
179 do_klass(Long_klass, java_lang_Long, Pre ) \
180 /*end*/
181
182
183 class SystemDictionary : AllStatic {
184 friend class VMStructs;
185 friend class CompactingPermGenGen;
186 friend class SystemDictionaryHandles;
187 NOT_PRODUCT(friend class instanceKlassKlass;)
188
189 public:
190 enum WKID {
191 NO_WKID = 0,
192
193 #define WK_KLASS_ENUM(name, symbol, ignore_o) WK_KLASS_ENUM_NAME(name), WK_KLASS_ENUM_NAME(symbol) = WK_KLASS_ENUM_NAME(name),
194 WK_KLASSES_DO(WK_KLASS_ENUM)
195 #undef WK_KLASS_ENUM
196
197 WKID_LIMIT,
198
199 FIRST_WKID = NO_WKID + 1
200 };
201
202 enum InitOption {
203 Pre, // preloaded; error if not present
204 Pre_JSR292, // preloaded if EnableInvokeDynamic
205
206 // Order is significant. Options before this point require resolve_or_fail.
207 // Options after this point will use resolve_or_null instead.
208
209 Opt, // preload tried; NULL if not present
210 Opt_Only_JDK14NewRef, // preload tried; use only with NewReflection
211 Opt_Only_JDK15, // preload tried; use only with JDK1.5+
212 OPTION_LIMIT,
213 CEIL_LG_OPTION_LIMIT = 4 // OPTION_LIMIT <= (1<<CEIL_LG_OPTION_LIMIT)
214 };
215
216
217 // Returns a class with a given class name and class loader. Loads the
218 // class if needed. If not found a NoClassDefFoundError or a
219 // ClassNotFoundException is thrown, depending on the value on the
220 // throw_error flag. For most uses the throw_error argument should be set
221 // to true.
222
223 static klassOop resolve_or_fail(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS);
224 // Convenient call for null loader and protection domain.
225 static klassOop resolve_or_fail(Symbol* class_name, bool throw_error, TRAPS);
226 private:
227 // handle error translation for resolve_or_null results
228 static klassOop handle_resolution_exception(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, KlassHandle klass_h, TRAPS);
229
230 public:
231
232 // Returns a class with a given class name and class loader.
233 // Loads the class if needed. If not found NULL is returned.
234 static klassOop resolve_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
235 // Version with null loader and protection domain
236 static klassOop resolve_or_null(Symbol* class_name, TRAPS);
237
238 // Resolve a superclass or superinterface. Called from ClassFileParser,
239 // parse_interfaces, resolve_instance_class_or_null, load_shared_class
240 // "child_name" is the class whose super class or interface is being resolved.
241 static klassOop resolve_super_or_fail(Symbol* child_name,
242 Symbol* class_name,
243 Handle class_loader,
244 Handle protection_domain,
245 bool is_superclass,
246 TRAPS);
247
248 // Parse new stream. This won't update the system dictionary or
249 // class hierarchy, simply parse the stream. Used by JVMTI RedefineClasses.
250 static klassOop parse_stream(Symbol* class_name,
251 Handle class_loader,
252 Handle protection_domain,
253 ClassFileStream* st,
254 TRAPS) {
255 KlassHandle nullHandle;
256 return parse_stream(class_name, class_loader, protection_domain, st, nullHandle, NULL, THREAD);
257 }
258 static klassOop parse_stream(Symbol* class_name,
259 Handle class_loader,
260 Handle protection_domain,
261 ClassFileStream* st,
262 KlassHandle host_klass,
263 GrowableArray<Handle>* cp_patches,
264 TRAPS);
265
266 // Resolve from stream (called by jni_DefineClass and JVM_DefineClass)
267 static klassOop resolve_from_stream(Symbol* class_name, Handle class_loader,
268 Handle protection_domain,
269 ClassFileStream* st, bool verify, TRAPS);
270
271 // Lookup an already loaded class. If not found NULL is returned.
272 static klassOop find(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
273
274 // Lookup an already loaded instance or array class.
275 // Do not make any queries to class loaders; consult only the cache.
276 // If not found NULL is returned.
277 static klassOop find_instance_or_array_klass(Symbol* class_name,
278 Handle class_loader,
279 Handle protection_domain,
280 TRAPS);
281
282 // Lookup an instance or array class that has already been loaded
283 // either into the given class loader, or else into another class
284 // loader that is constrained (via loader constraints) to produce
285 // a consistent class. Do not take protection domains into account.
286 // Do not make any queries to class loaders; consult only the cache.
287 // Return NULL if the class is not found.
288 //
289 // This function is a strict superset of find_instance_or_array_klass.
290 // This function (the unchecked version) makes a conservative prediction
291 // of the result of the checked version, assuming successful lookup.
292 // If both functions return non-null, they must return the same value.
293 // Also, the unchecked version may sometimes be non-null where the
294 // checked version is null. This can occur in several ways:
295 // 1. No query has yet been made to the class loader.
296 // 2. The class loader was queried, but chose not to delegate.
297 // 3. ClassLoader.checkPackageAccess rejected a proposed protection domain.
298 // 4. Loading was attempted, but there was a linkage error of some sort.
299 // In all of these cases, the loader constraints on this type are
300 // satisfied, and it is safe for classes in the given class loader
301 // to manipulate strongly-typed values of the found class, subject
302 // to local linkage and access checks.
303 static klassOop find_constrained_instance_or_array_klass(Symbol* class_name,
304 Handle class_loader,
305 TRAPS);
306
307 // Iterate over all klasses in dictionary
308 // Just the classes from defining class loaders
309 static void classes_do(void f(klassOop));
310 // Added for initialize_itable_for_klass to handle exceptions
311 static void classes_do(void f(klassOop, TRAPS), TRAPS);
312 // All classes, and their class loaders
313 static void classes_do(void f(klassOop, oop));
314 // All classes, and their class loaders
315 // (added for helpers that use HandleMarks and ResourceMarks)
316 static void classes_do(void f(klassOop, oop, TRAPS), TRAPS);
317 // All entries in the placeholder table and their class loaders
318 static void placeholders_do(void f(Symbol*, oop));
319
320 // Iterate over all methods in all klasses in dictionary
321 static void methods_do(void f(methodOop));
322
323 // Garbage collection support
324
325 // This method applies "blk->do_oop" to all the pointers to "system"
326 // classes and loaders.
327 static void always_strong_oops_do(OopClosure* blk);
328 static void always_strong_classes_do(OopClosure* blk);
329 // This method applies "blk->do_oop" to all the placeholders.
330 static void placeholders_do(OopClosure* blk);
331
332 // Unload (that is, break root links to) all unmarked classes and
333 // loaders. Returns "true" iff something was unloaded.
334 static bool do_unloading(BoolObjectClosure* is_alive);
335
336 static int calculate_systemdictionary_size(int loadedclasses);
337
338 // Applies "f->do_oop" to all root oops in the system dictionary.
339 static void oops_do(OopClosure* f);
340
341 // System loader lock
342 static oop system_loader_lock() { return _system_loader_lock_obj; }
343
344 private:
345 // Traverses preloaded oops: various system classes. These are
346 // guaranteed to be in the perm gen.
347 static void preloaded_oops_do(OopClosure* f);
348 static void lazily_loaded_oops_do(OopClosure* f);
349
350 public:
351 // Sharing support.
352 static void reorder_dictionary();
353 static void copy_buckets(char** top, char* end);
354 static void copy_table(char** top, char* end);
355 static void reverse();
356 static void set_shared_dictionary(HashtableBucket<mtClass>* t, int length,
357 int number_of_entries);
358 // Printing
359 static void print() PRODUCT_RETURN;
360 static void print_class_statistics() PRODUCT_RETURN;
361 static void print_method_statistics() PRODUCT_RETURN;
362
363 // Number of contained klasses
364 // This is both fully loaded classes and classes in the process
365 // of being loaded
366 static int number_of_classes();
367
368 // Monotonically increasing counter which grows as classes are
369 // loaded or modifications such as hot-swapping or setting/removing
370 // of breakpoints are performed
371 static inline int number_of_modifications() { assert_locked_or_safepoint(Compile_lock); return _number_of_modifications; }
372 // Needed by evolution and breakpoint code
373 static inline void notice_modification() { assert_locked_or_safepoint(Compile_lock); ++_number_of_modifications; }
374
375 // Verification
376 static void verify();
377
378 #ifdef ASSERT
379 static bool is_internal_format(Symbol* class_name);
380 #endif
381
382 // Verify class is in dictionary
383 static void verify_obj_klass_present(Handle obj,
384 Symbol* class_name,
385 Handle class_loader);
386
387 // Initialization
388 static void initialize(TRAPS);
389
390 // Fast access to commonly used classes (preloaded)
391 static klassOop check_klass(klassOop k) {
392 assert(k != NULL, "preloaded klass not initialized");
393 return k;
394 }
395
396 static klassOop check_klass_Pre( klassOop k) { return check_klass(k); }
397 static klassOop check_klass_Pre_JSR292(klassOop k) { return EnableInvokeDynamic ? check_klass(k) : k; }
398 static klassOop check_klass_Opt( klassOop k) { return k; }
399 static klassOop check_klass_Opt_Only_JDK15(klassOop k) {
400 assert(JDK_Version::is_gte_jdk15x_version(), "JDK 1.5 only");
401 return k;
402 }
403 static klassOop check_klass_Opt_Only_JDK14NewRef(klassOop k) {
404 assert(JDK_Version::is_gte_jdk14x_version() && UseNewReflection, "JDK 1.4 only");
405 // despite the optional loading, if you use this it must be present:
406 return check_klass(k);
407 }
408
409 static bool initialize_wk_klass(WKID id, int init_opt, TRAPS);
410 static void initialize_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS);
411 static void initialize_wk_klasses_through(WKID end_id, WKID &start_id, TRAPS) {
412 int limit = (int)end_id + 1;
413 initialize_wk_klasses_until((WKID) limit, start_id, THREAD);
414 }
415
416 public:
417 #define WK_KLASS_DECLARE(name, symbol, option) \
418 static klassOop name() { return check_klass_##option(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); }
419 WK_KLASSES_DO(WK_KLASS_DECLARE);
420 #undef WK_KLASS_DECLARE
421
422 static klassOop well_known_klass(WKID id) {
423 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
424 return _well_known_klasses[id];
425 }
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 klassOop 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(klassOop k); // inverse of box_klass
435
436 // methods returning lazily loaded klasses
437 // The corresponding method to load the class must be called before calling them.
438 static klassOop abstract_ownable_synchronizer_klass() { return check_klass(_abstract_ownable_synchronizer_klass); }
439
440 static void load_abstract_ownable_synchronizer_klass(TRAPS);
441
442 private:
443 // Tells whether ClassLoader.loadClassInternal is present
444 static bool has_loadClassInternal() { return _has_loadClassInternal; }
445
446 public:
447 // Tells whether ClassLoader.checkPackageAccess is present
448 static bool has_checkPackageAccess() { return _has_checkPackageAccess; }
449
450 static bool Class_klass_loaded() { return WK_KLASS(Class_klass) != NULL; }
451 static bool Cloneable_klass_loaded() { return WK_KLASS(Cloneable_klass) != NULL; }
452
453 // Returns default system loader
454 static oop java_system_loader();
455
456 // Compute the default system loader
457 static void compute_java_system_loader(TRAPS);
458
459 private:
460 // Mirrors for primitive classes (created eagerly)
461 static oop check_mirror(oop m) {
462 assert(m != NULL, "mirror not initialized");
463 return m;
464 }
465
466 public:
467 // Note: java_lang_Class::primitive_type is the inverse of java_mirror
468
469 // Check class loader constraints
470 static bool add_loader_constraint(Symbol* name, Handle loader1,
471 Handle loader2, TRAPS);
472 static char* check_signature_loaders(Symbol* signature, Handle loader1,
473 Handle loader2, bool is_method, TRAPS);
474
475 // JSR 292
476 // find a java.lang.invoke.MethodHandle.invoke* method for a given signature
477 // (asks Java to compute it if necessary, except in a compiler thread)
478 static methodHandle find_method_handle_invoker(Symbol* name,
479 Symbol* signature,
480 KlassHandle accessing_klass,
481 Handle *appendix_result,
482 Handle *method_type_result,
483 TRAPS);
484 // for a given signature, find the internal MethodHandle method (linkTo* or invokeBasic)
485 // (does not ask Java, since this is a low-level intrinsic defined by the JVM)
486 static methodHandle find_method_handle_intrinsic(vmIntrinsics::ID iid,
487 Symbol* signature,
488 TRAPS);
489 // find a java.lang.invoke.MethodType object for a given signature
490 // (asks Java to compute it if necessary, except in a compiler thread)
491 static Handle find_method_handle_type(Symbol* signature,
492 KlassHandle accessing_klass,
493 TRAPS);
494
495 // ask Java to compute a java.lang.invoke.MethodHandle object for a given CP entry
496 static Handle link_method_handle_constant(KlassHandle caller,
497 int ref_kind, //e.g., JVM_REF_invokeVirtual
498 KlassHandle callee,
499 Symbol* name,
500 Symbol* signature,
501 TRAPS);
502
503 // ask Java to create a dynamic call site, while linking an invokedynamic op
504 static methodHandle find_dynamic_call_site_invoker(KlassHandle caller,
505 Handle bootstrap_method,
506 Symbol* name,
507 Symbol* type,
508 Handle *appendix_result,
509 Handle *method_type_result,
510 TRAPS);
511
512 // Utility for printing loader "name" as part of tracing constraints
513 static const char* loader_name(oop loader) {
514 return ((loader) == NULL ? "<bootloader>" :
515 instanceKlass::cast((loader)->klass())->name()->as_C_string() );
516 }
517
518 // Record the error when the first attempt to resolve a reference from a constant
519 // pool entry to a class fails.
520 static void add_resolution_error(constantPoolHandle pool, int which, Symbol* error);
521 static Symbol* find_resolution_error(constantPoolHandle pool, int which);
522
523 private:
524
525 enum Constants {
526 _loader_constraint_size = 107, // number of entries in constraint table
527 _resolution_error_size = 107, // number of entries in resolution error table
528 _invoke_method_size = 139, // number of entries in invoke method table
529 _nof_buckets = 1009, // number of buckets in hash table for placeholders
530 _old_default_sdsize = 1009, // backward compat for system dictionary size
531 _prime_array_size = 8, // array of primes for system dictionary size
532 _average_depth_goal = 3 // goal for lookup length
533 };
534
535
536 // Static variables
537
538 // hashtable sizes for system dictionary to allow growth
539 // prime numbers for system dictionary size
540 static int _sdgeneration;
541 static const int _primelist[_prime_array_size];
542
543 // Hashtable holding loaded classes.
544 static Dictionary* _dictionary;
545
546 // Hashtable holding placeholders for classes being loaded.
547 static PlaceholderTable* _placeholders;
548
549 // Hashtable holding classes from the shared archive.
550 static Dictionary* _shared_dictionary;
551
552 // Monotonically increasing counter which grows with
553 // _number_of_classes as well as hot-swapping and breakpoint setting
554 // and removal.
555 static int _number_of_modifications;
556
557 // Lock object for system class loader
558 static oop _system_loader_lock_obj;
559
560 // Constraints on class loaders
561 static LoaderConstraintTable* _loader_constraints;
562
563 // Resolution errors
564 static ResolutionErrorTable* _resolution_errors;
565
566 // Invoke methods (JSR 292)
567 static SymbolPropertyTable* _invoke_method_table;
568
569 public:
570 // for VM_CounterDecay iteration support
571 friend class CounterDecay;
572 static klassOop try_get_next_class();
573
574 private:
575 static void validate_protection_domain(instanceKlassHandle klass,
576 Handle class_loader,
577 Handle protection_domain, TRAPS);
578
579 friend class VM_PopulateDumpSharedSpace;
580 friend class TraversePlaceholdersClosure;
581 static Dictionary* dictionary() { return _dictionary; }
582 static Dictionary* shared_dictionary() { return _shared_dictionary; }
583 static PlaceholderTable* placeholders() { return _placeholders; }
584 static LoaderConstraintTable* constraints() { return _loader_constraints; }
585 static ResolutionErrorTable* resolution_errors() { return _resolution_errors; }
586 static SymbolPropertyTable* invoke_method_table() { return _invoke_method_table; }
587
588 // Basic loading operations
589 static klassOop resolve_instance_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
590 static klassOop resolve_array_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
591 static instanceKlassHandle handle_parallel_super_load(Symbol* class_name, Symbol* supername, Handle class_loader, Handle protection_domain, Handle lockObject, TRAPS);
592 // Wait on SystemDictionary_lock; unlocks lockObject before
593 // waiting; relocks lockObject with correct recursion count
594 // after waiting, but before reentering SystemDictionary_lock
595 // to preserve lock order semantics.
596 static void double_lock_wait(Handle lockObject, TRAPS);
597 static void define_instance_class(instanceKlassHandle k, TRAPS);
598 static instanceKlassHandle find_or_define_instance_class(Symbol* class_name,
599 Handle class_loader,
600 instanceKlassHandle k, TRAPS);
601 static instanceKlassHandle load_shared_class(Symbol* class_name,
602 Handle class_loader, TRAPS);
603 static instanceKlassHandle load_shared_class(instanceKlassHandle ik,
604 Handle class_loader, TRAPS);
605 static instanceKlassHandle load_instance_class(Symbol* class_name, Handle class_loader, TRAPS);
606 static Handle compute_loader_lock_object(Handle class_loader, TRAPS);
607 static void check_loader_lock_contention(Handle loader_lock, TRAPS);
608 static bool is_parallelCapable(Handle class_loader);
609 static bool is_parallelDefine(Handle class_loader);
610
611 static klassOop find_shared_class(Symbol* class_name);
612
613 // Setup link to hierarchy
614 static void add_to_hierarchy(instanceKlassHandle k, TRAPS);
615
616 private:
617 // We pass in the hashtable index so we can calculate it outside of
618 // the SystemDictionary_lock.
619
620 // Basic find on loaded classes
621 static klassOop find_class(int index, unsigned int hash,
622 Symbol* name, Handle loader);
623 static klassOop find_class(Symbol* class_name, Handle class_loader);
624
625 // Basic find on classes in the midst of being loaded
626 static Symbol* find_placeholder(Symbol* name, Handle loader);
627
628 // Updating entry in dictionary
629 // Add a completely loaded class
630 static void add_klass(int index, Symbol* class_name,
631 Handle class_loader, KlassHandle obj);
632
633 // Add a placeholder for a class being loaded
634 static void add_placeholder(int index,
635 Symbol* class_name,
636 Handle class_loader);
637 static void remove_placeholder(int index,
638 Symbol* class_name,
639 Handle class_loader);
640
641 // Performs cleanups after resolve_super_or_fail. This typically needs
642 // to be called on failure.
643 // Won't throw, but can block.
644 static void resolution_cleanups(Symbol* class_name,
645 Handle class_loader,
646 TRAPS);
647
648 // Initialization
649 static void initialize_preloaded_classes(TRAPS);
650
651 // Class loader constraints
652 static void check_constraints(int index, unsigned int hash,
653 instanceKlassHandle k, Handle loader,
654 bool defining, TRAPS);
655 static void update_dictionary(int d_index, unsigned int d_hash,
656 int p_index, unsigned int p_hash,
657 instanceKlassHandle k, Handle loader, TRAPS);
658
659 // Variables holding commonly used klasses (preloaded)
660 static klassOop _well_known_klasses[];
661
662 // Lazily loaded klasses
663 static volatile klassOop _abstract_ownable_synchronizer_klass;
664
665 // table of box klasses (int_klass, etc.)
666 static klassOop _box_klasses[T_VOID+1];
667
668 static oop _java_system_loader;
669
670 static bool _has_loadClassInternal;
671 static bool _has_checkPackageAccess;
672 };
673
674 class SystemDictionaryHandles : AllStatic {
675 public:
676 #define WK_KLASS_HANDLE_DECLARE(name, ignore_symbol, option) \
677 static KlassHandle name() { \
678 SystemDictionary::name(); \
679 klassOop* loc = &SystemDictionary::_well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]; \
680 return KlassHandle(loc, true); \
681 }
682 WK_KLASSES_DO(WK_KLASS_HANDLE_DECLARE);
683 #undef WK_KLASS_HANDLE_DECLARE
684
685 static KlassHandle box_klass(BasicType t);
686 };
687
688 #endif // SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP