Mon, 16 Jul 2012 19:50:52 -0700
Merge
1 /*
2 * Copyright (c) 1997, 2012, 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.
22 *
23 */
25 #ifndef SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP
26 #define SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP
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"
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.
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 //
73 class Dictionary;
74 class PlaceholderTable;
75 class LoaderConstraintTable;
76 template <MEMFLAGS F> class HashtableBucket;
77 class ResolutionErrorTable;
78 class SymbolPropertyTable;
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.
86 #define WK_KLASS_ENUM_NAME(kname) kname##_knum
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.
95 #define WK_KLASSES_DO(template) \
96 /* well-known classes */ \
97 template(Object_klass, java_lang_Object, Pre) \
98 template(String_klass, java_lang_String, Pre) \
99 template(Class_klass, java_lang_Class, Pre) \
100 template(Cloneable_klass, java_lang_Cloneable, Pre) \
101 template(ClassLoader_klass, java_lang_ClassLoader, Pre) \
102 template(Serializable_klass, java_io_Serializable, Pre) \
103 template(System_klass, java_lang_System, Pre) \
104 template(Throwable_klass, java_lang_Throwable, Pre) \
105 template(Error_klass, java_lang_Error, Pre) \
106 template(ThreadDeath_klass, java_lang_ThreadDeath, Pre) \
107 template(Exception_klass, java_lang_Exception, Pre) \
108 template(RuntimeException_klass, java_lang_RuntimeException, Pre) \
109 template(ProtectionDomain_klass, java_security_ProtectionDomain, Pre) \
110 template(AccessControlContext_klass, java_security_AccessControlContext, Pre) \
111 template(ClassNotFoundException_klass, java_lang_ClassNotFoundException, Pre) \
112 template(NoClassDefFoundError_klass, java_lang_NoClassDefFoundError, Pre) \
113 template(LinkageError_klass, java_lang_LinkageError, Pre) \
114 template(ClassCastException_klass, java_lang_ClassCastException, Pre) \
115 template(ArrayStoreException_klass, java_lang_ArrayStoreException, Pre) \
116 template(VirtualMachineError_klass, java_lang_VirtualMachineError, Pre) \
117 template(OutOfMemoryError_klass, java_lang_OutOfMemoryError, Pre) \
118 template(StackOverflowError_klass, java_lang_StackOverflowError, Pre) \
119 template(IllegalMonitorStateException_klass, java_lang_IllegalMonitorStateException, Pre) \
120 template(Reference_klass, java_lang_ref_Reference, Pre) \
121 \
122 /* Preload ref klasses and set reference types */ \
123 template(SoftReference_klass, java_lang_ref_SoftReference, Pre) \
124 template(WeakReference_klass, java_lang_ref_WeakReference, Pre) \
125 template(FinalReference_klass, java_lang_ref_FinalReference, Pre) \
126 template(PhantomReference_klass, java_lang_ref_PhantomReference, Pre) \
127 template(Finalizer_klass, java_lang_ref_Finalizer, Pre) \
128 \
129 template(Thread_klass, java_lang_Thread, Pre) \
130 template(ThreadGroup_klass, java_lang_ThreadGroup, Pre) \
131 template(Properties_klass, java_util_Properties, Pre) \
132 template(reflect_AccessibleObject_klass, java_lang_reflect_AccessibleObject, Pre) \
133 template(reflect_Field_klass, java_lang_reflect_Field, Pre) \
134 template(reflect_Method_klass, java_lang_reflect_Method, Pre) \
135 template(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 template(reflect_MagicAccessorImpl_klass, sun_reflect_MagicAccessorImpl, Opt) \
141 template(reflect_MethodAccessorImpl_klass, sun_reflect_MethodAccessorImpl, Opt_Only_JDK14NewRef) \
142 template(reflect_ConstructorAccessorImpl_klass, sun_reflect_ConstructorAccessorImpl, Opt_Only_JDK14NewRef) \
143 template(reflect_DelegatingClassLoader_klass, sun_reflect_DelegatingClassLoader, Opt) \
144 template(reflect_ConstantPool_klass, sun_reflect_ConstantPool, Opt_Only_JDK15) \
145 template(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 template(MethodHandle_klass, java_lang_invoke_MethodHandle, Pre_JSR292) \
149 template(MemberName_klass, java_lang_invoke_MemberName, Pre_JSR292) \
150 template(MethodHandleNatives_klass, java_lang_invoke_MethodHandleNatives, Pre_JSR292) \
151 template(AdapterMethodHandle_klass, java_lang_invoke_AdapterMethodHandle, Pre_JSR292) \
152 template(BoundMethodHandle_klass, java_lang_invoke_BoundMethodHandle, Pre_JSR292) \
153 template(DirectMethodHandle_klass, java_lang_invoke_DirectMethodHandle, Pre_JSR292) \
154 template(MethodType_klass, java_lang_invoke_MethodType, Pre_JSR292) \
155 template(MethodTypeForm_klass, java_lang_invoke_MethodTypeForm, Pre_JSR292) \
156 template(BootstrapMethodError_klass, java_lang_BootstrapMethodError, Pre_JSR292) \
157 template(WrongMethodTypeException_klass, java_lang_invoke_WrongMethodTypeException, Pre_JSR292) \
158 template(CallSite_klass, java_lang_invoke_CallSite, Pre_JSR292) \
159 template(CountingMethodHandle_klass, java_lang_invoke_CountingMethodHandle, Opt) \
160 template(ConstantCallSite_klass, java_lang_invoke_ConstantCallSite, Pre_JSR292) \
161 template(MutableCallSite_klass, java_lang_invoke_MutableCallSite, Pre_JSR292) \
162 template(VolatileCallSite_klass, java_lang_invoke_VolatileCallSite, Pre_JSR292) \
163 /* Note: MethodHandle must be first, and VolatileCallSite last in group */ \
164 \
165 template(StringBuffer_klass, java_lang_StringBuffer, Pre) \
166 template(StringBuilder_klass, java_lang_StringBuilder, Pre) \
167 \
168 /* It's NULL in non-1.4 JDKs. */ \
169 template(StackTraceElement_klass, java_lang_StackTraceElement, Opt) \
170 /* Universe::is_gte_jdk14x_version() is not set up by this point. */ \
171 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \
172 template(nio_Buffer_klass, java_nio_Buffer, Opt) \
173 \
174 template(DownloadManager_klass, sun_jkernel_DownloadManager, Opt_Kernel) \
175 \
176 template(PostVMInitHook_klass, sun_misc_PostVMInitHook, Opt) \
177 \
178 /* Preload boxing klasses */ \
179 template(Boolean_klass, java_lang_Boolean, Pre) \
180 template(Character_klass, java_lang_Character, Pre) \
181 template(Float_klass, java_lang_Float, Pre) \
182 template(Double_klass, java_lang_Double, Pre) \
183 template(Byte_klass, java_lang_Byte, Pre) \
184 template(Short_klass, java_lang_Short, Pre) \
185 template(Integer_klass, java_lang_Integer, Pre) \
186 template(Long_klass, java_lang_Long, Pre) \
187 /*end*/
190 class SystemDictionary : AllStatic {
191 friend class VMStructs;
192 friend class CompactingPermGenGen;
193 friend class SystemDictionaryHandles;
194 NOT_PRODUCT(friend class instanceKlassKlass;)
196 public:
197 enum WKID {
198 NO_WKID = 0,
200 #define WK_KLASS_ENUM(name, symbol, ignore_o) WK_KLASS_ENUM_NAME(name), WK_KLASS_ENUM_NAME(symbol) = WK_KLASS_ENUM_NAME(name),
201 WK_KLASSES_DO(WK_KLASS_ENUM)
202 #undef WK_KLASS_ENUM
204 WKID_LIMIT,
206 FIRST_WKID = NO_WKID + 1
207 };
209 enum InitOption {
210 Pre, // preloaded; error if not present
211 Pre_JSR292, // preloaded if EnableInvokeDynamic
213 // Order is significant. Options before this point require resolve_or_fail.
214 // Options after this point will use resolve_or_null instead.
216 Opt, // preload tried; NULL if not present
217 Opt_Only_JDK14NewRef, // preload tried; use only with NewReflection
218 Opt_Only_JDK15, // preload tried; use only with JDK1.5+
219 Opt_Kernel, // preload tried only #ifdef KERNEL
220 OPTION_LIMIT,
221 CEIL_LG_OPTION_LIMIT = 4 // OPTION_LIMIT <= (1<<CEIL_LG_OPTION_LIMIT)
222 };
225 // Returns a class with a given class name and class loader. Loads the
226 // class if needed. If not found a NoClassDefFoundError or a
227 // ClassNotFoundException is thrown, depending on the value on the
228 // throw_error flag. For most uses the throw_error argument should be set
229 // to true.
231 static klassOop resolve_or_fail(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS);
232 // Convenient call for null loader and protection domain.
233 static klassOop resolve_or_fail(Symbol* class_name, bool throw_error, TRAPS);
234 private:
235 // handle error translation for resolve_or_null results
236 static klassOop handle_resolution_exception(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, KlassHandle klass_h, TRAPS);
238 public:
240 // Returns a class with a given class name and class loader.
241 // Loads the class if needed. If not found NULL is returned.
242 static klassOop resolve_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
243 // Version with null loader and protection domain
244 static klassOop resolve_or_null(Symbol* class_name, TRAPS);
246 // Resolve a superclass or superinterface. Called from ClassFileParser,
247 // parse_interfaces, resolve_instance_class_or_null, load_shared_class
248 // "child_name" is the class whose super class or interface is being resolved.
249 static klassOop resolve_super_or_fail(Symbol* child_name,
250 Symbol* class_name,
251 Handle class_loader,
252 Handle protection_domain,
253 bool is_superclass,
254 TRAPS);
256 // Parse new stream. This won't update the system dictionary or
257 // class hierarchy, simply parse the stream. Used by JVMTI RedefineClasses.
258 static klassOop parse_stream(Symbol* class_name,
259 Handle class_loader,
260 Handle protection_domain,
261 ClassFileStream* st,
262 TRAPS) {
263 KlassHandle nullHandle;
264 return parse_stream(class_name, class_loader, protection_domain, st, nullHandle, NULL, THREAD);
265 }
266 static klassOop parse_stream(Symbol* class_name,
267 Handle class_loader,
268 Handle protection_domain,
269 ClassFileStream* st,
270 KlassHandle host_klass,
271 GrowableArray<Handle>* cp_patches,
272 TRAPS);
274 // Resolve from stream (called by jni_DefineClass and JVM_DefineClass)
275 static klassOop resolve_from_stream(Symbol* class_name, Handle class_loader,
276 Handle protection_domain,
277 ClassFileStream* st, bool verify, TRAPS);
279 // Lookup an already loaded class. If not found NULL is returned.
280 static klassOop find(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
282 // Lookup an already loaded instance or array class.
283 // Do not make any queries to class loaders; consult only the cache.
284 // If not found NULL is returned.
285 static klassOop find_instance_or_array_klass(Symbol* class_name,
286 Handle class_loader,
287 Handle protection_domain,
288 TRAPS);
290 // If the given name is known to vmSymbols, return the well-know klass:
291 static klassOop find_well_known_klass(Symbol* class_name);
293 // Lookup an instance or array class that has already been loaded
294 // either into the given class loader, or else into another class
295 // loader that is constrained (via loader constraints) to produce
296 // a consistent class. Do not take protection domains into account.
297 // Do not make any queries to class loaders; consult only the cache.
298 // Return NULL if the class is not found.
299 //
300 // This function is a strict superset of find_instance_or_array_klass.
301 // This function (the unchecked version) makes a conservative prediction
302 // of the result of the checked version, assuming successful lookup.
303 // If both functions return non-null, they must return the same value.
304 // Also, the unchecked version may sometimes be non-null where the
305 // checked version is null. This can occur in several ways:
306 // 1. No query has yet been made to the class loader.
307 // 2. The class loader was queried, but chose not to delegate.
308 // 3. ClassLoader.checkPackageAccess rejected a proposed protection domain.
309 // 4. Loading was attempted, but there was a linkage error of some sort.
310 // In all of these cases, the loader constraints on this type are
311 // satisfied, and it is safe for classes in the given class loader
312 // to manipulate strongly-typed values of the found class, subject
313 // to local linkage and access checks.
314 static klassOop find_constrained_instance_or_array_klass(Symbol* class_name,
315 Handle class_loader,
316 TRAPS);
318 // Iterate over all klasses in dictionary
319 // Just the classes from defining class loaders
320 static void classes_do(void f(klassOop));
321 // Added for initialize_itable_for_klass to handle exceptions
322 static void classes_do(void f(klassOop, TRAPS), TRAPS);
323 // All classes, and their class loaders
324 static void classes_do(void f(klassOop, oop));
325 // All classes, and their class loaders
326 // (added for helpers that use HandleMarks and ResourceMarks)
327 static void classes_do(void f(klassOop, oop, TRAPS), TRAPS);
328 // All entries in the placeholder table and their class loaders
329 static void placeholders_do(void f(Symbol*, oop));
331 // Iterate over all methods in all klasses in dictionary
332 static void methods_do(void f(methodOop));
334 // Garbage collection support
336 // This method applies "blk->do_oop" to all the pointers to "system"
337 // classes and loaders.
338 static void always_strong_oops_do(OopClosure* blk);
339 static void always_strong_classes_do(OopClosure* blk);
340 // This method applies "blk->do_oop" to all the placeholders.
341 static void placeholders_do(OopClosure* blk);
343 // Unload (that is, break root links to) all unmarked classes and
344 // loaders. Returns "true" iff something was unloaded.
345 static bool do_unloading(BoolObjectClosure* is_alive);
347 static int calculate_systemdictionary_size(int loadedclasses);
349 // Applies "f->do_oop" to all root oops in the system dictionary.
350 static void oops_do(OopClosure* f);
352 // System loader lock
353 static oop system_loader_lock() { return _system_loader_lock_obj; }
355 private:
356 // Traverses preloaded oops: various system classes. These are
357 // guaranteed to be in the perm gen.
358 static void preloaded_oops_do(OopClosure* f);
359 static void lazily_loaded_oops_do(OopClosure* f);
361 public:
362 // Sharing support.
363 static void reorder_dictionary();
364 static void copy_buckets(char** top, char* end);
365 static void copy_table(char** top, char* end);
366 static void reverse();
367 static void set_shared_dictionary(HashtableBucket<mtClass>* t, int length,
368 int number_of_entries);
369 // Printing
370 static void print() PRODUCT_RETURN;
371 static void print_class_statistics() PRODUCT_RETURN;
372 static void print_method_statistics() PRODUCT_RETURN;
374 // Number of contained klasses
375 // This is both fully loaded classes and classes in the process
376 // of being loaded
377 static int number_of_classes();
379 // Monotonically increasing counter which grows as classes are
380 // loaded or modifications such as hot-swapping or setting/removing
381 // of breakpoints are performed
382 static inline int number_of_modifications() { assert_locked_or_safepoint(Compile_lock); return _number_of_modifications; }
383 // Needed by evolution and breakpoint code
384 static inline void notice_modification() { assert_locked_or_safepoint(Compile_lock); ++_number_of_modifications; }
386 // Verification
387 static void verify();
389 #ifdef ASSERT
390 static bool is_internal_format(Symbol* class_name);
391 #endif
393 // Verify class is in dictionary
394 static void verify_obj_klass_present(Handle obj,
395 Symbol* class_name,
396 Handle class_loader);
398 // Initialization
399 static void initialize(TRAPS);
401 // Fast access to commonly used classes (preloaded)
402 static klassOop check_klass(klassOop k) {
403 assert(k != NULL, "preloaded klass not initialized");
404 return k;
405 }
407 static klassOop check_klass_Pre(klassOop k) { return check_klass(k); }
408 static klassOop check_klass_Pre_JSR292(klassOop k) { return EnableInvokeDynamic ? check_klass(k) : k; }
409 static klassOop check_klass_Opt(klassOop k) { return k; }
410 static klassOop check_klass_Opt_Kernel(klassOop k) { return k; } //== Opt
411 static klassOop check_klass_Opt_Only_JDK15(klassOop k) {
412 assert(JDK_Version::is_gte_jdk15x_version(), "JDK 1.5 only");
413 return k;
414 }
415 static klassOop check_klass_Opt_Only_JDK14NewRef(klassOop k) {
416 assert(JDK_Version::is_gte_jdk14x_version() && UseNewReflection, "JDK 1.4 only");
417 // despite the optional loading, if you use this it must be present:
418 return check_klass(k);
419 }
421 static bool initialize_wk_klass(WKID id, int init_opt, TRAPS);
422 static void initialize_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS);
423 static void initialize_wk_klasses_through(WKID end_id, WKID &start_id, TRAPS) {
424 int limit = (int)end_id + 1;
425 initialize_wk_klasses_until((WKID) limit, start_id, THREAD);
426 }
428 public:
429 #define WK_KLASS_DECLARE(name, symbol, option) \
430 static klassOop name() { return check_klass_##option(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); }
431 WK_KLASSES_DO(WK_KLASS_DECLARE);
432 #undef WK_KLASS_DECLARE
434 static klassOop well_known_klass(WKID id) {
435 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
436 return _well_known_klasses[id];
437 }
439 // Local definition for direct access to the private array:
440 #define WK_KLASS(name) _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]
442 static klassOop box_klass(BasicType t) {
443 assert((uint)t < T_VOID+1, "range check");
444 return check_klass(_box_klasses[t]);
445 }
446 static BasicType box_klass_type(klassOop k); // inverse of box_klass
448 // methods returning lazily loaded klasses
449 // The corresponding method to load the class must be called before calling them.
450 static klassOop abstract_ownable_synchronizer_klass() { return check_klass(_abstract_ownable_synchronizer_klass); }
452 static void load_abstract_ownable_synchronizer_klass(TRAPS);
454 private:
455 // Tells whether ClassLoader.loadClassInternal is present
456 static bool has_loadClassInternal() { return _has_loadClassInternal; }
458 public:
459 // Tells whether ClassLoader.checkPackageAccess is present
460 static bool has_checkPackageAccess() { return _has_checkPackageAccess; }
462 static bool Class_klass_loaded() { return WK_KLASS(Class_klass) != NULL; }
463 static bool Cloneable_klass_loaded() { return WK_KLASS(Cloneable_klass) != NULL; }
465 // Returns default system loader
466 static oop java_system_loader();
468 // Compute the default system loader
469 static void compute_java_system_loader(TRAPS);
471 private:
472 // Mirrors for primitive classes (created eagerly)
473 static oop check_mirror(oop m) {
474 assert(m != NULL, "mirror not initialized");
475 return m;
476 }
478 public:
479 // Note: java_lang_Class::primitive_type is the inverse of java_mirror
481 // Check class loader constraints
482 static bool add_loader_constraint(Symbol* name, Handle loader1,
483 Handle loader2, TRAPS);
484 static char* check_signature_loaders(Symbol* signature, Handle loader1,
485 Handle loader2, bool is_method, TRAPS);
487 // JSR 292
488 // find the java.lang.invoke.MethodHandles::invoke method for a given signature
489 static methodOop find_method_handle_invoke(Symbol* name,
490 Symbol* signature,
491 KlassHandle accessing_klass,
492 TRAPS);
493 // ask Java to compute a java.lang.invoke.MethodType object for a given signature
494 static Handle find_method_handle_type(Symbol* signature,
495 KlassHandle accessing_klass,
496 bool for_invokeGeneric,
497 bool& return_bcp_flag,
498 TRAPS);
499 // ask Java to compute a java.lang.invoke.MethodHandle object for a given CP entry
500 static Handle link_method_handle_constant(KlassHandle caller,
501 int ref_kind, //e.g., JVM_REF_invokeVirtual
502 KlassHandle callee,
503 Symbol* name,
504 Symbol* signature,
505 TRAPS);
506 // ask Java to create a dynamic call site, while linking an invokedynamic op
507 static Handle make_dynamic_call_site(Handle bootstrap_method,
508 // Callee information:
509 Symbol* name,
510 methodHandle signature_invoker,
511 Handle info,
512 // Caller information:
513 methodHandle caller_method,
514 int caller_bci,
515 TRAPS);
517 // coordinate with Java about bootstrap methods
518 static Handle find_bootstrap_method(methodHandle caller_method,
519 int caller_bci, // N.B. must be an invokedynamic
520 int cache_index, // must be corresponding main_entry
521 Handle &argument_info_result, // static BSM arguments, if any
522 TRAPS);
524 // Utility for printing loader "name" as part of tracing constraints
525 static const char* loader_name(oop loader) {
526 return ((loader) == NULL ? "<bootloader>" :
527 instanceKlass::cast((loader)->klass())->name()->as_C_string() );
528 }
530 // Record the error when the first attempt to resolve a reference from a constant
531 // pool entry to a class fails.
532 static void add_resolution_error(constantPoolHandle pool, int which, Symbol* error);
533 static Symbol* find_resolution_error(constantPoolHandle pool, int which);
535 private:
537 enum Constants {
538 _loader_constraint_size = 107, // number of entries in constraint table
539 _resolution_error_size = 107, // number of entries in resolution error table
540 _invoke_method_size = 139, // number of entries in invoke method table
541 _nof_buckets = 1009, // number of buckets in hash table for placeholders
542 _old_default_sdsize = 1009, // backward compat for system dictionary size
543 _prime_array_size = 8, // array of primes for system dictionary size
544 _average_depth_goal = 3 // goal for lookup length
545 };
548 // Static variables
550 // hashtable sizes for system dictionary to allow growth
551 // prime numbers for system dictionary size
552 static int _sdgeneration;
553 static const int _primelist[_prime_array_size];
555 // Hashtable holding loaded classes.
556 static Dictionary* _dictionary;
558 // Hashtable holding placeholders for classes being loaded.
559 static PlaceholderTable* _placeholders;
561 // Hashtable holding classes from the shared archive.
562 static Dictionary* _shared_dictionary;
564 // Monotonically increasing counter which grows with
565 // _number_of_classes as well as hot-swapping and breakpoint setting
566 // and removal.
567 static int _number_of_modifications;
569 // Lock object for system class loader
570 static oop _system_loader_lock_obj;
572 // Constraints on class loaders
573 static LoaderConstraintTable* _loader_constraints;
575 // Resolution errors
576 static ResolutionErrorTable* _resolution_errors;
578 // Invoke methods (JSR 292)
579 static SymbolPropertyTable* _invoke_method_table;
581 public:
582 // for VM_CounterDecay iteration support
583 friend class CounterDecay;
584 static klassOop try_get_next_class();
586 private:
587 static void validate_protection_domain(instanceKlassHandle klass,
588 Handle class_loader,
589 Handle protection_domain, TRAPS);
591 friend class VM_PopulateDumpSharedSpace;
592 friend class TraversePlaceholdersClosure;
593 static Dictionary* dictionary() { return _dictionary; }
594 static Dictionary* shared_dictionary() { return _shared_dictionary; }
595 static PlaceholderTable* placeholders() { return _placeholders; }
596 static LoaderConstraintTable* constraints() { return _loader_constraints; }
597 static ResolutionErrorTable* resolution_errors() { return _resolution_errors; }
598 static SymbolPropertyTable* invoke_method_table() { return _invoke_method_table; }
600 // Basic loading operations
601 static klassOop resolve_instance_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
602 static klassOop resolve_array_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
603 static instanceKlassHandle handle_parallel_super_load(Symbol* class_name, Symbol* supername, Handle class_loader, Handle protection_domain, Handle lockObject, TRAPS);
604 // Wait on SystemDictionary_lock; unlocks lockObject before
605 // waiting; relocks lockObject with correct recursion count
606 // after waiting, but before reentering SystemDictionary_lock
607 // to preserve lock order semantics.
608 static void double_lock_wait(Handle lockObject, TRAPS);
609 static void define_instance_class(instanceKlassHandle k, TRAPS);
610 static instanceKlassHandle find_or_define_instance_class(Symbol* class_name,
611 Handle class_loader,
612 instanceKlassHandle k, TRAPS);
613 static instanceKlassHandle load_shared_class(Symbol* class_name,
614 Handle class_loader, TRAPS);
615 static instanceKlassHandle load_shared_class(instanceKlassHandle ik,
616 Handle class_loader, TRAPS);
617 static instanceKlassHandle load_instance_class(Symbol* class_name, Handle class_loader, TRAPS);
618 static Handle compute_loader_lock_object(Handle class_loader, TRAPS);
619 static void check_loader_lock_contention(Handle loader_lock, TRAPS);
620 static bool is_parallelCapable(Handle class_loader);
621 static bool is_parallelDefine(Handle class_loader);
623 static klassOop find_shared_class(Symbol* class_name);
625 // Setup link to hierarchy
626 static void add_to_hierarchy(instanceKlassHandle k, TRAPS);
628 private:
629 // We pass in the hashtable index so we can calculate it outside of
630 // the SystemDictionary_lock.
632 // Basic find on loaded classes
633 static klassOop find_class(int index, unsigned int hash,
634 Symbol* name, Handle loader);
635 static klassOop find_class(Symbol* class_name, Handle class_loader);
637 // Basic find on classes in the midst of being loaded
638 static Symbol* find_placeholder(Symbol* name, Handle loader);
640 // Updating entry in dictionary
641 // Add a completely loaded class
642 static void add_klass(int index, Symbol* class_name,
643 Handle class_loader, KlassHandle obj);
645 // Add a placeholder for a class being loaded
646 static void add_placeholder(int index,
647 Symbol* class_name,
648 Handle class_loader);
649 static void remove_placeholder(int index,
650 Symbol* class_name,
651 Handle class_loader);
653 // Performs cleanups after resolve_super_or_fail. This typically needs
654 // to be called on failure.
655 // Won't throw, but can block.
656 static void resolution_cleanups(Symbol* class_name,
657 Handle class_loader,
658 TRAPS);
660 // Initialization
661 static void initialize_preloaded_classes(TRAPS);
663 // Class loader constraints
664 static void check_constraints(int index, unsigned int hash,
665 instanceKlassHandle k, Handle loader,
666 bool defining, TRAPS);
667 static void update_dictionary(int d_index, unsigned int d_hash,
668 int p_index, unsigned int p_hash,
669 instanceKlassHandle k, Handle loader, TRAPS);
671 // Variables holding commonly used klasses (preloaded)
672 static klassOop _well_known_klasses[];
674 // Lazily loaded klasses
675 static volatile klassOop _abstract_ownable_synchronizer_klass;
677 // table of box klasses (int_klass, etc.)
678 static klassOop _box_klasses[T_VOID+1];
680 static oop _java_system_loader;
682 static bool _has_loadClassInternal;
683 static bool _has_checkPackageAccess;
684 };
686 class SystemDictionaryHandles : AllStatic {
687 public:
688 #define WK_KLASS_HANDLE_DECLARE(name, ignore_symbol, option) \
689 static KlassHandle name() { \
690 SystemDictionary::name(); \
691 klassOop* loc = &SystemDictionary::_well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]; \
692 return KlassHandle(loc, true); \
693 }
694 WK_KLASSES_DO(WK_KLASS_HANDLE_DECLARE);
695 #undef WK_KLASS_HANDLE_DECLARE
697 static KlassHandle box_klass(BasicType t);
698 };
700 #endif // SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP