Fri, 25 Jan 2013 10:04:08 -0500
8000692: Remove old KERNEL code
Summary: Removed depreciated kernel VM source code from hotspot VM
Reviewed-by: dholmes, acorn
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.
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] -> Klass*
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(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_Parameter_klass, java_lang_reflect_Parameter, Opt ) \
135 do_klass(reflect_Method_klass, java_lang_reflect_Method, Pre ) \
136 do_klass(reflect_Constructor_klass, java_lang_reflect_Constructor, Pre ) \
137 \
138 /* NOTE: needed too early in bootstrapping process to have checks based on JDK version */ \
139 /* Universe::is_gte_jdk14x_version() is not set up by this point. */ \
140 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \
141 do_klass(lambda_MagicLambdaImpl_klass, java_lang_invoke_MagicLambdaImpl, Opt ) \
142 do_klass(reflect_MagicAccessorImpl_klass, sun_reflect_MagicAccessorImpl, Opt ) \
143 do_klass(reflect_MethodAccessorImpl_klass, sun_reflect_MethodAccessorImpl, Opt_Only_JDK14NewRef) \
144 do_klass(reflect_ConstructorAccessorImpl_klass, sun_reflect_ConstructorAccessorImpl, Opt_Only_JDK14NewRef) \
145 do_klass(reflect_DelegatingClassLoader_klass, sun_reflect_DelegatingClassLoader, Opt ) \
146 do_klass(reflect_ConstantPool_klass, sun_reflect_ConstantPool, Opt_Only_JDK15 ) \
147 do_klass(reflect_UnsafeStaticFieldAccessorImpl_klass, sun_reflect_UnsafeStaticFieldAccessorImpl, Opt_Only_JDK15 ) \
148 \
149 /* support for dynamic typing; it's OK if these are NULL in earlier JDKs */ \
150 do_klass(MethodHandle_klass, java_lang_invoke_MethodHandle, Pre_JSR292 ) \
151 do_klass(MemberName_klass, java_lang_invoke_MemberName, Pre_JSR292 ) \
152 do_klass(MethodHandleNatives_klass, java_lang_invoke_MethodHandleNatives, Pre_JSR292 ) \
153 do_klass(LambdaForm_klass, java_lang_invoke_LambdaForm, Opt ) \
154 do_klass(MethodType_klass, java_lang_invoke_MethodType, Pre_JSR292 ) \
155 do_klass(BootstrapMethodError_klass, java_lang_BootstrapMethodError, Pre_JSR292 ) \
156 do_klass(CallSite_klass, java_lang_invoke_CallSite, Pre_JSR292 ) \
157 do_klass(ConstantCallSite_klass, java_lang_invoke_ConstantCallSite, Pre_JSR292 ) \
158 do_klass(MutableCallSite_klass, java_lang_invoke_MutableCallSite, Pre_JSR292 ) \
159 do_klass(VolatileCallSite_klass, java_lang_invoke_VolatileCallSite, Pre_JSR292 ) \
160 /* Note: MethodHandle must be first, and VolatileCallSite last in group */ \
161 \
162 do_klass(StringBuffer_klass, java_lang_StringBuffer, Pre ) \
163 do_klass(StringBuilder_klass, java_lang_StringBuilder, Pre ) \
164 \
165 /* It's NULL in non-1.4 JDKs. */ \
166 do_klass(StackTraceElement_klass, java_lang_StackTraceElement, Opt ) \
167 /* Universe::is_gte_jdk14x_version() is not set up by this point. */ \
168 /* It's okay if this turns out to be NULL in non-1.4 JDKs. */ \
169 do_klass(nio_Buffer_klass, java_nio_Buffer, Opt ) \
170 \
171 do_klass(PostVMInitHook_klass, sun_misc_PostVMInitHook, Opt ) \
172 \
173 /* Preload boxing klasses */ \
174 do_klass(Boolean_klass, java_lang_Boolean, Pre ) \
175 do_klass(Character_klass, java_lang_Character, Pre ) \
176 do_klass(Float_klass, java_lang_Float, Pre ) \
177 do_klass(Double_klass, java_lang_Double, Pre ) \
178 do_klass(Byte_klass, java_lang_Byte, Pre ) \
179 do_klass(Short_klass, java_lang_Short, Pre ) \
180 do_klass(Integer_klass, java_lang_Integer, Pre ) \
181 do_klass(Long_klass, java_lang_Long, Pre ) \
182 /*end*/
185 class SystemDictionary : AllStatic {
186 friend class VMStructs;
187 friend class SystemDictionaryHandles;
189 public:
190 enum WKID {
191 NO_WKID = 0,
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
197 WKID_LIMIT,
199 FIRST_WKID = NO_WKID + 1
200 };
202 enum InitOption {
203 Pre, // preloaded; error if not present
204 Pre_JSR292, // preloaded if EnableInvokeDynamic
206 // Order is significant. Options before this point require resolve_or_fail.
207 // Options after this point will use resolve_or_null instead.
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 };
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.
223 static Klass* 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 Klass* resolve_or_fail(Symbol* class_name, bool throw_error, TRAPS);
226 private:
227 // handle error translation for resolve_or_null results
228 static Klass* handle_resolution_exception(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, KlassHandle klass_h, TRAPS);
230 public:
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 Klass* resolve_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
235 // Version with null loader and protection domain
236 static Klass* resolve_or_null(Symbol* class_name, TRAPS);
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 Klass* 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);
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 Klass* 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 Klass* 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);
266 // Resolve from stream (called by jni_DefineClass and JVM_DefineClass)
267 static Klass* resolve_from_stream(Symbol* class_name, Handle class_loader,
268 Handle protection_domain,
269 ClassFileStream* st, bool verify, TRAPS);
271 // Lookup an already loaded class. If not found NULL is returned.
272 static Klass* find(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
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 Klass* find_instance_or_array_klass(Symbol* class_name,
278 Handle class_loader,
279 Handle protection_domain,
280 TRAPS);
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 Klass* find_constrained_instance_or_array_klass(Symbol* class_name,
304 Handle class_loader,
305 TRAPS);
307 // Iterate over all klasses in dictionary
308 // Just the classes from defining class loaders
309 static void classes_do(void f(Klass*));
310 // Added for initialize_itable_for_klass to handle exceptions
311 static void classes_do(void f(Klass*, TRAPS), TRAPS);
312 // All classes, and their class loaders
313 static void classes_do(void f(Klass*, ClassLoaderData*));
314 // All classes, and their class loaders
315 // (added for helpers that use HandleMarks and ResourceMarks)
316 static void classes_do(void f(Klass*, ClassLoaderData*, TRAPS), TRAPS);
317 // All entries in the placeholder table and their class loaders
318 static void placeholders_do(void f(Symbol*));
320 // Iterate over all methods in all klasses in dictionary
321 static void methods_do(void f(Method*));
323 // Garbage collection support
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(KlassClosure* closure);
330 // Unload (that is, break root links to) all unmarked classes and
331 // loaders. Returns "true" iff something was unloaded.
332 static bool do_unloading(BoolObjectClosure* is_alive);
334 static int calculate_systemdictionary_size(int loadedclasses);
336 // Applies "f->do_oop" to all root oops in the system dictionary.
337 static void oops_do(OopClosure* f);
339 // System loader lock
340 static oop system_loader_lock() { return _system_loader_lock_obj; }
342 private:
343 // Extended Redefine classes support (tbi)
344 static void preloaded_classes_do(KlassClosure* f);
345 static void lazily_loaded_classes_do(KlassClosure* f);
346 public:
347 // Sharing support.
348 static void reorder_dictionary();
349 static void copy_buckets(char** top, char* end);
350 static void copy_table(char** top, char* end);
351 static void reverse();
352 static void set_shared_dictionary(HashtableBucket<mtClass>* t, int length,
353 int number_of_entries);
354 // Printing
355 static void print() PRODUCT_RETURN;
356 static void print_class_statistics() PRODUCT_RETURN;
357 static void print_method_statistics() PRODUCT_RETURN;
359 // Number of contained klasses
360 // This is both fully loaded classes and classes in the process
361 // of being loaded
362 static int number_of_classes();
364 // Monotonically increasing counter which grows as classes are
365 // loaded or modifications such as hot-swapping or setting/removing
366 // of breakpoints are performed
367 static inline int number_of_modifications() { assert_locked_or_safepoint(Compile_lock); return _number_of_modifications; }
368 // Needed by evolution and breakpoint code
369 static inline void notice_modification() { assert_locked_or_safepoint(Compile_lock); ++_number_of_modifications; }
371 // Verification
372 static void verify();
374 #ifdef ASSERT
375 static bool is_internal_format(Symbol* class_name);
376 #endif
378 // Verify class is in dictionary
379 static void verify_obj_klass_present(Symbol* class_name,
380 ClassLoaderData* loader_data);
382 // Initialization
383 static void initialize(TRAPS);
385 // Fast access to commonly used classes (preloaded)
386 static Klass* check_klass(Klass* k) {
387 assert(k != NULL, "preloaded klass not initialized");
388 return k;
389 }
391 static Klass* check_klass_Pre( Klass* k) { return check_klass(k); }
392 static Klass* check_klass_Pre_JSR292(Klass* k) { return EnableInvokeDynamic ? check_klass(k) : k; }
393 static Klass* check_klass_Opt( Klass* k) { return k; }
394 static Klass* check_klass_Opt_Only_JDK15(Klass* k) {
395 assert(JDK_Version::is_gte_jdk15x_version(), "JDK 1.5 only");
396 return k;
397 }
398 static Klass* check_klass_Opt_Only_JDK14NewRef(Klass* k) {
399 assert(JDK_Version::is_gte_jdk14x_version() && UseNewReflection, "JDK 1.4 only");
400 // despite the optional loading, if you use this it must be present:
401 return check_klass(k);
402 }
404 static bool initialize_wk_klass(WKID id, int init_opt, TRAPS);
405 static void initialize_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS);
406 static void initialize_wk_klasses_through(WKID end_id, WKID &start_id, TRAPS) {
407 int limit = (int)end_id + 1;
408 initialize_wk_klasses_until((WKID) limit, start_id, THREAD);
409 }
411 public:
412 #define WK_KLASS_DECLARE(name, symbol, option) \
413 static Klass* name() { return check_klass_##option(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); } \
414 static Klass** name##_addr() { \
415 return &SystemDictionary::_well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]; \
416 }
417 WK_KLASSES_DO(WK_KLASS_DECLARE);
418 #undef WK_KLASS_DECLARE
420 static Klass* well_known_klass(WKID id) {
421 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
422 return _well_known_klasses[id];
423 }
425 static Klass** well_known_klass_addr(WKID id) {
426 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
427 return &_well_known_klasses[id];
428 }
430 // Local definition for direct access to the private array:
431 #define WK_KLASS(name) _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]
433 static Klass* box_klass(BasicType t) {
434 assert((uint)t < T_VOID+1, "range check");
435 return check_klass(_box_klasses[t]);
436 }
437 static BasicType box_klass_type(Klass* k); // inverse of box_klass
439 // methods returning lazily loaded klasses
440 // The corresponding method to load the class must be called before calling them.
441 static Klass* abstract_ownable_synchronizer_klass() { return check_klass(_abstract_ownable_synchronizer_klass); }
443 static void load_abstract_ownable_synchronizer_klass(TRAPS);
445 private:
446 // Tells whether ClassLoader.loadClassInternal is present
447 static bool has_loadClassInternal() { return _has_loadClassInternal; }
449 // Returns the class loader data to be used when looking up/updating the
450 // system dictionary.
451 static ClassLoaderData *class_loader_data(Handle class_loader) {
452 return ClassLoaderData::class_loader_data(class_loader());
453 }
455 public:
456 // Tells whether ClassLoader.checkPackageAccess is present
457 static bool has_checkPackageAccess() { return _has_checkPackageAccess; }
459 static bool Parameter_klass_loaded() { return WK_KLASS(reflect_Parameter_klass) != NULL; }
460 static bool Class_klass_loaded() { return WK_KLASS(Class_klass) != NULL; }
461 static bool Cloneable_klass_loaded() { return WK_KLASS(Cloneable_klass) != NULL; }
462 static bool Object_klass_loaded() { return WK_KLASS(Object_klass) != NULL; }
463 static bool ClassLoader_klass_loaded() { return WK_KLASS(ClassLoader_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 // Register a new class loader
472 static ClassLoaderData* register_loader(Handle class_loader, TRAPS);
473 private:
474 // Mirrors for primitive classes (created eagerly)
475 static oop check_mirror(oop m) {
476 assert(m != NULL, "mirror not initialized");
477 return m;
478 }
480 public:
481 // Note: java_lang_Class::primitive_type is the inverse of java_mirror
483 // Check class loader constraints
484 static bool add_loader_constraint(Symbol* name, Handle loader1,
485 Handle loader2, TRAPS);
486 static char* check_signature_loaders(Symbol* signature, Handle loader1,
487 Handle loader2, bool is_method, TRAPS);
489 // JSR 292
490 // find a java.lang.invoke.MethodHandle.invoke* method for a given signature
491 // (asks Java to compute it if necessary, except in a compiler thread)
492 static methodHandle find_method_handle_invoker(Symbol* name,
493 Symbol* signature,
494 KlassHandle accessing_klass,
495 Handle *appendix_result,
496 Handle *method_type_result,
497 TRAPS);
498 // for a given signature, find the internal MethodHandle method (linkTo* or invokeBasic)
499 // (does not ask Java, since this is a low-level intrinsic defined by the JVM)
500 static methodHandle find_method_handle_intrinsic(vmIntrinsics::ID iid,
501 Symbol* signature,
502 TRAPS);
503 // find a java.lang.invoke.MethodType object for a given signature
504 // (asks Java to compute it if necessary, except in a compiler thread)
505 static Handle find_method_handle_type(Symbol* signature,
506 KlassHandle accessing_klass,
507 TRAPS);
509 // ask Java to compute a java.lang.invoke.MethodHandle object for a given CP entry
510 static Handle link_method_handle_constant(KlassHandle caller,
511 int ref_kind, //e.g., JVM_REF_invokeVirtual
512 KlassHandle callee,
513 Symbol* name,
514 Symbol* signature,
515 TRAPS);
517 // ask Java to create a dynamic call site, while linking an invokedynamic op
518 static methodHandle find_dynamic_call_site_invoker(KlassHandle caller,
519 Handle bootstrap_method,
520 Symbol* name,
521 Symbol* type,
522 Handle *appendix_result,
523 Handle *method_type_result,
524 TRAPS);
526 // Utility for printing loader "name" as part of tracing constraints
527 static const char* loader_name(oop loader) {
528 return ((loader) == NULL ? "<bootloader>" :
529 InstanceKlass::cast((loader)->klass())->name()->as_C_string() );
530 }
531 static const char* loader_name(ClassLoaderData* loader_data) {
532 return (loader_data->class_loader() == NULL ? "<bootloader>" :
533 InstanceKlass::cast((loader_data->class_loader())->klass())->name()->as_C_string() );
534 }
536 // Record the error when the first attempt to resolve a reference from a constant
537 // pool entry to a class fails.
538 static void add_resolution_error(constantPoolHandle pool, int which, Symbol* error);
539 static void delete_resolution_error(ConstantPool* pool);
540 static Symbol* find_resolution_error(constantPoolHandle pool, int which);
542 private:
544 enum Constants {
545 _loader_constraint_size = 107, // number of entries in constraint table
546 _resolution_error_size = 107, // number of entries in resolution error table
547 _invoke_method_size = 139, // number of entries in invoke method table
548 _nof_buckets = 1009, // number of buckets in hash table for placeholders
549 _old_default_sdsize = 1009, // backward compat for system dictionary size
550 _prime_array_size = 8, // array of primes for system dictionary size
551 _average_depth_goal = 3 // goal for lookup length
552 };
555 // Static variables
557 // hashtable sizes for system dictionary to allow growth
558 // prime numbers for system dictionary size
559 static int _sdgeneration;
560 static const int _primelist[_prime_array_size];
562 // Hashtable holding loaded classes.
563 static Dictionary* _dictionary;
565 // Hashtable holding placeholders for classes being loaded.
566 static PlaceholderTable* _placeholders;
568 // Hashtable holding classes from the shared archive.
569 static Dictionary* _shared_dictionary;
571 // Monotonically increasing counter which grows with
572 // _number_of_classes as well as hot-swapping and breakpoint setting
573 // and removal.
574 static int _number_of_modifications;
576 // Lock object for system class loader
577 static oop _system_loader_lock_obj;
579 // Constraints on class loaders
580 static LoaderConstraintTable* _loader_constraints;
582 // Resolution errors
583 static ResolutionErrorTable* _resolution_errors;
585 // Invoke methods (JSR 292)
586 static SymbolPropertyTable* _invoke_method_table;
588 public:
589 // for VM_CounterDecay iteration support
590 friend class CounterDecay;
591 static Klass* try_get_next_class();
593 private:
594 static void validate_protection_domain(instanceKlassHandle klass,
595 Handle class_loader,
596 Handle protection_domain, TRAPS);
598 friend class VM_PopulateDumpSharedSpace;
599 friend class TraversePlaceholdersClosure;
600 static Dictionary* dictionary() { return _dictionary; }
601 static Dictionary* shared_dictionary() { return _shared_dictionary; }
602 static PlaceholderTable* placeholders() { return _placeholders; }
603 static LoaderConstraintTable* constraints() { return _loader_constraints; }
604 static ResolutionErrorTable* resolution_errors() { return _resolution_errors; }
605 static SymbolPropertyTable* invoke_method_table() { return _invoke_method_table; }
607 // Basic loading operations
608 static Klass* resolve_instance_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
609 static Klass* resolve_array_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
610 static instanceKlassHandle handle_parallel_super_load(Symbol* class_name, Symbol* supername, Handle class_loader, Handle protection_domain, Handle lockObject, TRAPS);
611 // Wait on SystemDictionary_lock; unlocks lockObject before
612 // waiting; relocks lockObject with correct recursion count
613 // after waiting, but before reentering SystemDictionary_lock
614 // to preserve lock order semantics.
615 static void double_lock_wait(Handle lockObject, TRAPS);
616 static void define_instance_class(instanceKlassHandle k, TRAPS);
617 static instanceKlassHandle find_or_define_instance_class(Symbol* class_name,
618 Handle class_loader,
619 instanceKlassHandle k, TRAPS);
620 static instanceKlassHandle load_shared_class(Symbol* class_name,
621 Handle class_loader, TRAPS);
622 static instanceKlassHandle load_shared_class(instanceKlassHandle ik,
623 Handle class_loader, TRAPS);
624 static instanceKlassHandle load_instance_class(Symbol* class_name, Handle class_loader, TRAPS);
625 static Handle compute_loader_lock_object(Handle class_loader, TRAPS);
626 static void check_loader_lock_contention(Handle loader_lock, TRAPS);
627 static bool is_parallelCapable(Handle class_loader);
628 static bool is_parallelDefine(Handle class_loader);
630 static Klass* find_shared_class(Symbol* class_name);
632 // Setup link to hierarchy
633 static void add_to_hierarchy(instanceKlassHandle k, TRAPS);
635 private:
636 // We pass in the hashtable index so we can calculate it outside of
637 // the SystemDictionary_lock.
639 // Basic find on loaded classes
640 static Klass* find_class(int index, unsigned int hash,
641 Symbol* name, ClassLoaderData* loader_data);
642 static Klass* find_class(Symbol* class_name, ClassLoaderData* loader_data);
644 // Basic find on classes in the midst of being loaded
645 static Symbol* find_placeholder(Symbol* name, ClassLoaderData* loader_data);
647 // Updating entry in dictionary
648 // Add a completely loaded class
649 static void add_klass(int index, Symbol* class_name,
650 ClassLoaderData* loader_data, KlassHandle obj);
652 // Add a placeholder for a class being loaded
653 static void add_placeholder(int index,
654 Symbol* class_name,
655 ClassLoaderData* loader_data);
656 static void remove_placeholder(int index,
657 Symbol* class_name,
658 ClassLoaderData* loader_data);
660 // Performs cleanups after resolve_super_or_fail. This typically needs
661 // to be called on failure.
662 // Won't throw, but can block.
663 static void resolution_cleanups(Symbol* class_name,
664 ClassLoaderData* loader_data,
665 TRAPS);
667 // Initialization
668 static void initialize_preloaded_classes(TRAPS);
670 // Class loader constraints
671 static void check_constraints(int index, unsigned int hash,
672 instanceKlassHandle k, Handle loader,
673 bool defining, TRAPS);
674 static void update_dictionary(int d_index, unsigned int d_hash,
675 int p_index, unsigned int p_hash,
676 instanceKlassHandle k, Handle loader,
677 TRAPS);
679 // Variables holding commonly used klasses (preloaded)
680 static Klass* _well_known_klasses[];
682 // Lazily loaded klasses
683 static Klass* volatile _abstract_ownable_synchronizer_klass;
685 // table of box klasses (int_klass, etc.)
686 static Klass* _box_klasses[T_VOID+1];
688 static oop _java_system_loader;
690 static bool _has_loadClassInternal;
691 static bool _has_checkPackageAccess;
692 };
694 #endif // SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP