jdk8-mips64-public/hotspot: src/share/vm/classfile/systemDictionary.hpp@2c6ef90f030a (annotated)

src/share/vm/classfile/systemDictionary.hpp@2c6ef90f030a (annotated)

src/share/vm/classfile/systemDictionary.hpp

Mon, 07 Jul 2014 10:12:40 +0200

author: stefank
date: Mon, 07 Jul 2014 10:12:40 +0200
changeset 6992: 2c6ef90f030a
parent 6626: 9428a0b94204
child 7089: 6e0cb14ce59b
permissions: -rw-r--r--

8049421: G1 Class Unloading after completing a concurrent mark cycle
Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com

 /*
  * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #ifndef SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP
 #define SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP
 #include "classfile/classFileStream.hpp"
 #include "classfile/classLoader.hpp"
 #include "oops/objArrayOop.hpp"
 #include "oops/symbol.hpp"
 #include "runtime/java.hpp"
 #include "runtime/reflectionUtils.hpp"
 #include "utilities/hashtable.hpp"
 #include "utilities/hashtable.inline.hpp"
 // The system dictionary stores all loaded classes and maps:
 //
 //   [class name,class loader] -> class   i.e.  [Symbol*,oop] -> Klass*
 //
 // Classes are loaded lazily. The default VM class loader is
 // represented as NULL.
 // The underlying data structure is an open hash table with a fixed number
 // of buckets. During loading the loader object is locked, (for the VM loader
 // a private lock object is used). Class loading can thus be done concurrently,
 // but only by different loaders.
 //
 // During loading a placeholder (name, loader) is temporarily placed in
 // a side data structure, and is used to detect ClassCircularityErrors
 // and to perform verification during GC.  A GC can occur in the midst
 // of class loading, as we call out to Java, have to take locks, etc.
 //
 // When class loading is finished, a new entry is added to the system
 // dictionary and the place holder is removed. Note that the protection
 // domain field of the system dictionary has not yet been filled in when
 // the "real" system dictionary entry is created.
 //
 // Clients of this class who are interested in finding if a class has
 // been completely loaded -- not classes in the process of being loaded --
 // can read the SystemDictionary unlocked. This is safe because
 //    - entries are only deleted at safepoints
 //    - readers cannot come to a safepoint while actively examining
 //         an entry  (an entry cannot be deleted from under a reader)
 //    - entries must be fully formed before they are available to concurrent
 //         readers (we must ensure write ordering)
 //
 // Note that placeholders are deleted at any time, as they are removed
 // when a class is completely loaded. Therefore, readers as well as writers
 // of placeholders must hold the SystemDictionary_lock.
 //
 class Dictionary;
 class PlaceholderTable;
 class LoaderConstraintTable;
 template <MEMFLAGS F> class HashtableBucket;
 class ResolutionErrorTable;
 class SymbolPropertyTable;
 class Ticks;
 // Certain classes are preloaded, such as java.lang.Object and java.lang.String.
 // They are all "well-known", in the sense that no class loader is allowed
 // to provide a different definition.
 //
 // These klasses must all have names defined in vmSymbols.
 #define WK_KLASS_ENUM_NAME(kname)    kname##_knum
 // Each well-known class has a short klass name (like object_klass),
 // a vmSymbol name (like java_lang_Object), and a flag word
 // that makes some minor distinctions, like whether the klass
 // is preloaded, optional, release-specific, etc.
 // The order of these definitions is significant; it is the order in which
 // preloading is actually performed by initialize_preloaded_classes.
 #define WK_KLASSES_DO(do_klass)                                                                                          \
   /* well-known classes */                                                                                               \
   do_klass(Object_klass,                                java_lang_Object,                          Pre                 ) \
   do_klass(String_klass,                                java_lang_String,                          Pre                 ) \
   do_klass(Class_klass,                                 java_lang_Class,                           Pre                 ) \
   do_klass(Cloneable_klass,                             java_lang_Cloneable,                       Pre                 ) \
   do_klass(ClassLoader_klass,                           java_lang_ClassLoader,                     Pre                 ) \
   do_klass(Serializable_klass,                          java_io_Serializable,                      Pre                 ) \
   do_klass(System_klass,                                java_lang_System,                          Pre                 ) \
   do_klass(Throwable_klass,                             java_lang_Throwable,                       Pre                 ) \
   do_klass(Error_klass,                                 java_lang_Error,                           Pre                 ) \
   do_klass(ThreadDeath_klass,                           java_lang_ThreadDeath,                     Pre                 ) \
   do_klass(Exception_klass,                             java_lang_Exception,                       Pre                 ) \
   do_klass(RuntimeException_klass,                      java_lang_RuntimeException,                Pre                 ) \
   do_klass(SecurityManager_klass,                       java_lang_SecurityManager,                 Pre                 ) \
   do_klass(ProtectionDomain_klass,                      java_security_ProtectionDomain,            Pre                 ) \
   do_klass(AccessControlContext_klass,                  java_security_AccessControlContext,        Pre                 ) \
   do_klass(ClassNotFoundException_klass,                java_lang_ClassNotFoundException,          Pre                 ) \
   do_klass(NoClassDefFoundError_klass,                  java_lang_NoClassDefFoundError,            Pre                 ) \
   do_klass(LinkageError_klass,                          java_lang_LinkageError,                    Pre                 ) \
   do_klass(ClassCastException_klass,                    java_lang_ClassCastException,              Pre                 ) \
   do_klass(ArrayStoreException_klass,                   java_lang_ArrayStoreException,             Pre                 ) \
   do_klass(VirtualMachineError_klass,                   java_lang_VirtualMachineError,             Pre                 ) \
   do_klass(OutOfMemoryError_klass,                      java_lang_OutOfMemoryError,                Pre                 ) \
   do_klass(StackOverflowError_klass,                    java_lang_StackOverflowError,              Pre                 ) \
   do_klass(IllegalMonitorStateException_klass,          java_lang_IllegalMonitorStateException,    Pre                 ) \
   do_klass(Reference_klass,                             java_lang_ref_Reference,                   Pre                 ) \
                                                                                                                          \
   /* Preload ref klasses and set reference types */                                                                      \
   do_klass(SoftReference_klass,                         java_lang_ref_SoftReference,               Pre                 ) \
   do_klass(WeakReference_klass,                         java_lang_ref_WeakReference,               Pre                 ) \
   do_klass(FinalReference_klass,                        java_lang_ref_FinalReference,              Pre                 ) \
   do_klass(PhantomReference_klass,                      java_lang_ref_PhantomReference,            Pre                 ) \
   do_klass(Finalizer_klass,                             java_lang_ref_Finalizer,                   Pre                 ) \
                                                                                                                          \
   do_klass(Thread_klass,                                java_lang_Thread,                          Pre                 ) \
   do_klass(ThreadGroup_klass,                           java_lang_ThreadGroup,                     Pre                 ) \
   do_klass(Properties_klass,                            java_util_Properties,                      Pre                 ) \
   do_klass(reflect_AccessibleObject_klass,              java_lang_reflect_AccessibleObject,        Pre                 ) \
   do_klass(reflect_Field_klass,                         java_lang_reflect_Field,                   Pre                 ) \
   do_klass(reflect_Parameter_klass,                     java_lang_reflect_Parameter,               Opt                 ) \
   do_klass(reflect_Method_klass,                        java_lang_reflect_Method,                  Pre                 ) \
   do_klass(reflect_Constructor_klass,                   java_lang_reflect_Constructor,             Pre                 ) \
                                                                                                                          \
   /* NOTE: needed too early in bootstrapping process to have checks based on JDK version */                              \
   /* Universe::is_gte_jdk14x_version() is not set up by this point. */                                                   \
   /* It's okay if this turns out to be NULL in non-1.4 JDKs. */                                                          \
   do_klass(reflect_MagicAccessorImpl_klass,             sun_reflect_MagicAccessorImpl,             Opt                 ) \
   do_klass(reflect_MethodAccessorImpl_klass,            sun_reflect_MethodAccessorImpl,            Opt_Only_JDK14NewRef) \
   do_klass(reflect_ConstructorAccessorImpl_klass,       sun_reflect_ConstructorAccessorImpl,       Opt_Only_JDK14NewRef) \
   do_klass(reflect_DelegatingClassLoader_klass,         sun_reflect_DelegatingClassLoader,         Opt                 ) \
   do_klass(reflect_ConstantPool_klass,                  sun_reflect_ConstantPool,                  Opt_Only_JDK15      ) \
   do_klass(reflect_UnsafeStaticFieldAccessorImpl_klass, sun_reflect_UnsafeStaticFieldAccessorImpl, Opt_Only_JDK15      ) \
   do_klass(reflect_CallerSensitive_klass,               sun_reflect_CallerSensitive,               Opt                 ) \
                                                                                                                          \
   /* support for dynamic typing; it's OK if these are NULL in earlier JDKs */                                            \
   do_klass(DirectMethodHandle_klass,                    java_lang_invoke_DirectMethodHandle,       Opt                 ) \
   do_klass(MethodHandle_klass,                          java_lang_invoke_MethodHandle,             Pre_JSR292          ) \
   do_klass(MemberName_klass,                            java_lang_invoke_MemberName,               Pre_JSR292          ) \
   do_klass(MethodHandleNatives_klass,                   java_lang_invoke_MethodHandleNatives,      Pre_JSR292          ) \
   do_klass(LambdaForm_klass,                            java_lang_invoke_LambdaForm,               Opt                 ) \
   do_klass(MethodType_klass,                            java_lang_invoke_MethodType,               Pre_JSR292          ) \
   do_klass(BootstrapMethodError_klass,                  java_lang_BootstrapMethodError,            Pre_JSR292          ) \
   do_klass(CallSite_klass,                              java_lang_invoke_CallSite,                 Pre_JSR292          ) \
   do_klass(ConstantCallSite_klass,                      java_lang_invoke_ConstantCallSite,         Pre_JSR292          ) \
   do_klass(MutableCallSite_klass,                       java_lang_invoke_MutableCallSite,          Pre_JSR292          ) \
   do_klass(VolatileCallSite_klass,                      java_lang_invoke_VolatileCallSite,         Pre_JSR292          ) \
   /* Note: MethodHandle must be first, and VolatileCallSite last in group */                                             \
                                                                                                                          \
   do_klass(StringBuffer_klass,                          java_lang_StringBuffer,                    Pre                 ) \
   do_klass(StringBuilder_klass,                         java_lang_StringBuilder,                   Pre                 ) \
   do_klass(misc_Unsafe_klass,                           sun_misc_Unsafe,                           Pre                 ) \
                                                                                                                          \
   /* It's NULL in non-1.4 JDKs. */                                                                                       \
   do_klass(StackTraceElement_klass,                     java_lang_StackTraceElement,               Opt                 ) \
   /* Universe::is_gte_jdk14x_version() is not set up by this point. */                                                   \
   /* It's okay if this turns out to be NULL in non-1.4 JDKs. */                                                          \
   do_klass(nio_Buffer_klass,                            java_nio_Buffer,                           Opt                 ) \
                                                                                                                          \
   /* Preload boxing klasses */                                                                                           \
   do_klass(Boolean_klass,                               java_lang_Boolean,                         Pre                 ) \
   do_klass(Character_klass,                             java_lang_Character,                       Pre                 ) \
   do_klass(Float_klass,                                 java_lang_Float,                           Pre                 ) \
   do_klass(Double_klass,                                java_lang_Double,                          Pre                 ) \
   do_klass(Byte_klass,                                  java_lang_Byte,                            Pre                 ) \
   do_klass(Short_klass,                                 java_lang_Short,                           Pre                 ) \
   do_klass(Integer_klass,                               java_lang_Integer,                         Pre                 ) \
   do_klass(Long_klass,                                  java_lang_Long,                            Pre                 ) \
   /*end*/
 class SystemDictionary : AllStatic {
   friend class VMStructs;
   friend class SystemDictionaryHandles;
  public:
   enum WKID {
     NO_WKID = 0,
     #define WK_KLASS_ENUM(name, symbol, ignore_o) WK_KLASS_ENUM_NAME(name), WK_KLASS_ENUM_NAME(symbol) = WK_KLASS_ENUM_NAME(name),
     WK_KLASSES_DO(WK_KLASS_ENUM)
     #undef WK_KLASS_ENUM
     WKID_LIMIT,
     FIRST_WKID = NO_WKID + 1
   };
   enum InitOption {
     Pre,                        // preloaded; error if not present
     Pre_JSR292,                 // preloaded if EnableInvokeDynamic
     // Order is significant.  Options before this point require resolve_or_fail.
     // Options after this point will use resolve_or_null instead.
     Opt,                        // preload tried; NULL if not present
     Opt_Only_JDK14NewRef,       // preload tried; use only with NewReflection
     Opt_Only_JDK15,             // preload tried; use only with JDK1.5+
     OPTION_LIMIT,
     CEIL_LG_OPTION_LIMIT = 4    // OPTION_LIMIT <= (1<<CEIL_LG_OPTION_LIMIT)
   };
   // Returns a class with a given class name and class loader.  Loads the
   // class if needed. If not found a NoClassDefFoundError or a
   // ClassNotFoundException is thrown, depending on the value on the
   // throw_error flag.  For most uses the throw_error argument should be set
   // to true.
   static Klass* resolve_or_fail(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS);
   // Convenient call for null loader and protection domain.
   static Klass* resolve_or_fail(Symbol* class_name, bool throw_error, TRAPS);
 private:
   // handle error translation for resolve_or_null results
   static Klass* handle_resolution_exception(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, KlassHandle klass_h, TRAPS);
 public:
   // Returns a class with a given class name and class loader.
   // Loads the class if needed. If not found NULL is returned.
   static Klass* resolve_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
   // Version with null loader and protection domain
   static Klass* resolve_or_null(Symbol* class_name, TRAPS);
   // Resolve a superclass or superinterface. Called from ClassFileParser,
   // parse_interfaces, resolve_instance_class_or_null, load_shared_class
   // "child_name" is the class whose super class or interface is being resolved.
   static Klass* resolve_super_or_fail(Symbol* child_name,
                                         Symbol* class_name,
                                         Handle class_loader,
                                         Handle protection_domain,
                                         bool is_superclass,
                                         TRAPS);
   // Parse new stream. This won't update the system dictionary or
   // class hierarchy, simply parse the stream. Used by JVMTI RedefineClasses.
   static Klass* parse_stream(Symbol* class_name,
                                Handle class_loader,
                                Handle protection_domain,
                                ClassFileStream* st,
                                TRAPS) {
     KlassHandle nullHandle;
     return parse_stream(class_name, class_loader, protection_domain, st, nullHandle, NULL, THREAD);
   }
   static Klass* parse_stream(Symbol* class_name,
                                Handle class_loader,
                                Handle protection_domain,
                                ClassFileStream* st,
                                KlassHandle host_klass,
                                GrowableArray<Handle>* cp_patches,
                                TRAPS);
   // Resolve from stream (called by jni_DefineClass and JVM_DefineClass)
   static Klass* resolve_from_stream(Symbol* class_name, Handle class_loader,
                                       Handle protection_domain,
                                       ClassFileStream* st, bool verify, TRAPS);
   // Lookup an already loaded class. If not found NULL is returned.
   static Klass* find(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
   // Lookup an already loaded instance or array class.
   // Do not make any queries to class loaders; consult only the cache.
   // If not found NULL is returned.
   static Klass* find_instance_or_array_klass(Symbol* class_name,
                                                Handle class_loader,
                                                Handle protection_domain,
                                                TRAPS);
   // Lookup an instance or array class that has already been loaded
   // either into the given class loader, or else into another class
   // loader that is constrained (via loader constraints) to produce
   // a consistent class.  Do not take protection domains into account.
   // Do not make any queries to class loaders; consult only the cache.
   // Return NULL if the class is not found.
   //
   // This function is a strict superset of find_instance_or_array_klass.
   // This function (the unchecked version) makes a conservative prediction
   // of the result of the checked version, assuming successful lookup.
   // If both functions return non-null, they must return the same value.
   // Also, the unchecked version may sometimes be non-null where the
   // checked version is null.  This can occur in several ways:
   //   1. No query has yet been made to the class loader.
   //   2. The class loader was queried, but chose not to delegate.
   //   3. ClassLoader.checkPackageAccess rejected a proposed protection domain.
   //   4. Loading was attempted, but there was a linkage error of some sort.
   // In all of these cases, the loader constraints on this type are
   // satisfied, and it is safe for classes in the given class loader
   // to manipulate strongly-typed values of the found class, subject
   // to local linkage and access checks.
   static Klass* find_constrained_instance_or_array_klass(Symbol* class_name,
                                                            Handle class_loader,
                                                            TRAPS);
   // Iterate over all klasses in dictionary
   //   Just the classes from defining class loaders
   static void classes_do(void f(Klass*));
   // Added for initialize_itable_for_klass to handle exceptions
   static void classes_do(void f(Klass*, TRAPS), TRAPS);
   //   All classes, and their class loaders
   static void classes_do(void f(Klass*, ClassLoaderData*));
   static void placeholders_do(void f(Symbol*));
   // Iterate over all methods in all klasses in dictionary
   static void methods_do(void f(Method*));
   // Garbage collection support
   // This method applies "blk->do_oop" to all the pointers to "system"
   // classes and loaders.
   static void always_strong_oops_do(OopClosure* blk);
   static void always_strong_classes_do(KlassClosure* closure);
   // Unload (that is, break root links to) all unmarked classes and
   // loaders.  Returns "true" iff something was unloaded.
   static bool do_unloading(BoolObjectClosure* is_alive);
   static int calculate_systemdictionary_size(int loadedclasses);
   // Applies "f->do_oop" to all root oops in the system dictionary.
   static void oops_do(OopClosure* f);
   static void roots_oops_do(OopClosure* strong, OopClosure* weak);
   // System loader lock
   static oop system_loader_lock()           { return _system_loader_lock_obj; }
 private:
   // Extended Redefine classes support (tbi)
   static void preloaded_classes_do(KlassClosure* f);
   static void lazily_loaded_classes_do(KlassClosure* f);
 public:
   // Sharing support.
   static void reorder_dictionary();
   static void copy_buckets(char** top, char* end);
   static void copy_table(char** top, char* end);
   static void reverse();
   static void set_shared_dictionary(HashtableBucket<mtClass>* t, int length,
                                     int number_of_entries);
   // Printing
   static void print()                   PRODUCT_RETURN;
   static void print_class_statistics()  PRODUCT_RETURN;
   static void print_method_statistics() PRODUCT_RETURN;
   // Number of contained klasses
   // This is both fully loaded classes and classes in the process
   // of being loaded
   static int number_of_classes();
   // Monotonically increasing counter which grows as classes are
   // loaded or modifications such as hot-swapping or setting/removing
   // of breakpoints are performed
   static inline int number_of_modifications()     { assert_locked_or_safepoint(Compile_lock); return _number_of_modifications; }
   // Needed by evolution and breakpoint code
   static inline void notice_modification()        { assert_locked_or_safepoint(Compile_lock); ++_number_of_modifications;      }
   // Verification
   static void verify();
 #ifdef ASSERT
   static bool is_internal_format(Symbol* class_name);
 #endif
   // Initialization
   static void initialize(TRAPS);
   // Fast access to commonly used classes (preloaded)
   static Klass* check_klass(Klass* k) {
     assert(k != NULL, "preloaded klass not initialized");
     return k;
   }
   static Klass* check_klass_Pre(       Klass* k) { return check_klass(k); }
   static Klass* check_klass_Pre_JSR292(Klass* k) { return EnableInvokeDynamic ? check_klass(k) : k; }
   static Klass* check_klass_Opt(       Klass* k) { return k; }
   static Klass* check_klass_Opt_Only_JDK15(Klass* k) {
     assert(JDK_Version::is_gte_jdk15x_version(), "JDK 1.5 only");
     return k;
   }
   static Klass* check_klass_Opt_Only_JDK14NewRef(Klass* k) {
     assert(JDK_Version::is_gte_jdk14x_version() && UseNewReflection, "JDK 1.4 only");
     // despite the optional loading, if you use this it must be present:
     return check_klass(k);
   }
   static bool initialize_wk_klass(WKID id, int init_opt, TRAPS);
   static void initialize_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS);
   static void initialize_wk_klasses_through(WKID end_id, WKID &start_id, TRAPS) {
     int limit = (int)end_id + 1;
     initialize_wk_klasses_until((WKID) limit, start_id, THREAD);
   }
 public:
   #define WK_KLASS_DECLARE(name, symbol, option) \
     static Klass* name() { return check_klass_##option(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); } \
     static Klass** name##_addr() {                                                                       \
       return &SystemDictionary::_well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)];           \
     }
   WK_KLASSES_DO(WK_KLASS_DECLARE);
   #undef WK_KLASS_DECLARE
   static Klass* well_known_klass(WKID id) {
     assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
     return _well_known_klasses[id];
   }
   static Klass** well_known_klass_addr(WKID id) {
     assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
     return &_well_known_klasses[id];
   }
   // Local definition for direct access to the private array:
   #define WK_KLASS(name) _well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]
   static Klass* box_klass(BasicType t) {
     assert((uint)t < T_VOID+1, "range check");
     return check_klass(_box_klasses[t]);
   }
   static BasicType box_klass_type(Klass* k);  // inverse of box_klass
   // methods returning lazily loaded klasses
   // The corresponding method to load the class must be called before calling them.
   static Klass* abstract_ownable_synchronizer_klass() { return check_klass(_abstract_ownable_synchronizer_klass); }
   static void load_abstract_ownable_synchronizer_klass(TRAPS);
 private:
   // Tells whether ClassLoader.loadClassInternal is present
   static bool has_loadClassInternal()       { return _has_loadClassInternal; }
   // Returns the class loader data to be used when looking up/updating the
   // system dictionary.
   static ClassLoaderData *class_loader_data(Handle class_loader) {
     return ClassLoaderData::class_loader_data(class_loader());
   }
 public:
   // Tells whether ClassLoader.checkPackageAccess is present
   static bool has_checkPackageAccess()      { return _has_checkPackageAccess; }
   static bool Parameter_klass_loaded()      { return WK_KLASS(reflect_Parameter_klass) != NULL; }
   static bool Class_klass_loaded()          { return WK_KLASS(Class_klass) != NULL; }
   static bool Cloneable_klass_loaded()      { return WK_KLASS(Cloneable_klass) != NULL; }
   static bool Object_klass_loaded()         { return WK_KLASS(Object_klass) != NULL; }
   static bool ClassLoader_klass_loaded()    { return WK_KLASS(ClassLoader_klass) != NULL; }
   // Returns default system loader
   static oop java_system_loader();
   // Compute the default system loader
   static void compute_java_system_loader(TRAPS);
   // Register a new class loader
   static ClassLoaderData* register_loader(Handle class_loader, TRAPS);
 private:
   // Mirrors for primitive classes (created eagerly)
   static oop check_mirror(oop m) {
     assert(m != NULL, "mirror not initialized");
     return m;
   }
 public:
   // Note:  java_lang_Class::primitive_type is the inverse of java_mirror
   // Check class loader constraints
   static bool add_loader_constraint(Symbol* name, Handle loader1,
                                     Handle loader2, TRAPS);
   static Symbol* check_signature_loaders(Symbol* signature, Handle loader1,
                                          Handle loader2, bool is_method, TRAPS);
   // JSR 292
   // find a java.lang.invoke.MethodHandle.invoke* method for a given signature
   // (asks Java to compute it if necessary, except in a compiler thread)
   static methodHandle find_method_handle_invoker(Symbol* name,
                                                  Symbol* signature,
                                                  KlassHandle accessing_klass,
                                                  Handle *appendix_result,
                                                  Handle *method_type_result,
                                                  TRAPS);
   // for a given signature, find the internal MethodHandle method (linkTo* or invokeBasic)
   // (does not ask Java, since this is a low-level intrinsic defined by the JVM)
   static methodHandle find_method_handle_intrinsic(vmIntrinsics::ID iid,
                                                    Symbol* signature,
                                                    TRAPS);
   // find a java.lang.invoke.MethodType object for a given signature
   // (asks Java to compute it if necessary, except in a compiler thread)
   static Handle    find_method_handle_type(Symbol* signature,
                                            KlassHandle accessing_klass,
                                            TRAPS);
   // ask Java to compute a java.lang.invoke.MethodHandle object for a given CP entry
   static Handle    link_method_handle_constant(KlassHandle caller,
                                                int ref_kind, //e.g., JVM_REF_invokeVirtual
                                                KlassHandle callee,
                                                Symbol* name,
                                                Symbol* signature,
                                                TRAPS);
   // ask Java to create a dynamic call site, while linking an invokedynamic op
   static methodHandle find_dynamic_call_site_invoker(KlassHandle caller,
                                                      Handle bootstrap_method,
                                                      Symbol* name,
                                                      Symbol* type,
                                                      Handle *appendix_result,
                                                      Handle *method_type_result,
                                                      TRAPS);
   // Utility for printing loader "name" as part of tracing constraints
   static const char* loader_name(oop loader) {
     return ((loader) == NULL ? "<bootloader>" :
             InstanceKlass::cast((loader)->klass())->name()->as_C_string() );
   }
   static const char* loader_name(ClassLoaderData* loader_data) {
     return (loader_data->class_loader() == NULL ? "<bootloader>" :
             InstanceKlass::cast((loader_data->class_loader())->klass())->name()->as_C_string() );
   }
   // Record the error when the first attempt to resolve a reference from a constant
   // pool entry to a class fails.
   static void add_resolution_error(constantPoolHandle pool, int which, Symbol* error);
   static void delete_resolution_error(ConstantPool* pool);
   static Symbol* find_resolution_error(constantPoolHandle pool, int which);
  private:
   enum Constants {
     _loader_constraint_size = 107,                     // number of entries in constraint table
     _resolution_error_size  = 107,                     // number of entries in resolution error table
     _invoke_method_size     = 139,                     // number of entries in invoke method table
     _nof_buckets            = 1009,                    // number of buckets in hash table for placeholders
     _old_default_sdsize     = 1009,                    // backward compat for system dictionary size
     _prime_array_size       = 8,                       // array of primes for system dictionary size
     _average_depth_goal     = 3                        // goal for lookup length
   };
   // Static variables
   // hashtable sizes for system dictionary to allow growth
   // prime numbers for system dictionary size
   static int                     _sdgeneration;
   static const int               _primelist[_prime_array_size];
   // Hashtable holding loaded classes.
   static Dictionary*            _dictionary;
   // Hashtable holding placeholders for classes being loaded.
   static PlaceholderTable*       _placeholders;
   // Hashtable holding classes from the shared archive.
   static Dictionary*             _shared_dictionary;
   // Monotonically increasing counter which grows with
   // _number_of_classes as well as hot-swapping and breakpoint setting
   // and removal.
   static int                     _number_of_modifications;
   // Lock object for system class loader
   static oop                     _system_loader_lock_obj;
   // Constraints on class loaders
   static LoaderConstraintTable*  _loader_constraints;
   // Resolution errors
   static ResolutionErrorTable*   _resolution_errors;
   // Invoke methods (JSR 292)
   static SymbolPropertyTable*    _invoke_method_table;
 public:
   // for VM_CounterDecay iteration support
   friend class CounterDecay;
   static Klass* try_get_next_class();
 private:
   static void validate_protection_domain(instanceKlassHandle klass,
                                          Handle class_loader,
                                          Handle protection_domain, TRAPS);
   friend class VM_PopulateDumpSharedSpace;
   friend class TraversePlaceholdersClosure;
   static Dictionary*         dictionary() { return _dictionary; }
   static Dictionary*         shared_dictionary() { return _shared_dictionary; }
   static PlaceholderTable*   placeholders() { return _placeholders; }
   static LoaderConstraintTable* constraints() { return _loader_constraints; }
   static ResolutionErrorTable* resolution_errors() { return _resolution_errors; }
   static SymbolPropertyTable* invoke_method_table() { return _invoke_method_table; }
   // Basic loading operations
   static Klass* resolve_instance_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
   static Klass* resolve_array_class_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS);
   static instanceKlassHandle handle_parallel_super_load(Symbol* class_name, Symbol* supername, Handle class_loader, Handle protection_domain, Handle lockObject, TRAPS);
   // Wait on SystemDictionary_lock; unlocks lockObject before
   // waiting; relocks lockObject with correct recursion count
   // after waiting, but before reentering SystemDictionary_lock
   // to preserve lock order semantics.
   static void double_lock_wait(Handle lockObject, TRAPS);
   static void define_instance_class(instanceKlassHandle k, TRAPS);
   static instanceKlassHandle find_or_define_instance_class(Symbol* class_name,
                                                 Handle class_loader,
                                                 instanceKlassHandle k, TRAPS);
   static instanceKlassHandle load_shared_class(Symbol* class_name,
                                                Handle class_loader, TRAPS);
   static instanceKlassHandle load_shared_class(instanceKlassHandle ik,
                                                Handle class_loader, TRAPS);
   static instanceKlassHandle load_instance_class(Symbol* class_name, Handle class_loader, TRAPS);
   static Handle compute_loader_lock_object(Handle class_loader, TRAPS);
   static void check_loader_lock_contention(Handle loader_lock, TRAPS);
   static bool is_parallelCapable(Handle class_loader);
   static bool is_parallelDefine(Handle class_loader);
 public:
   static bool is_ext_class_loader(Handle class_loader);
 private:
   static Klass* find_shared_class(Symbol* class_name);
   // Setup link to hierarchy
   static void add_to_hierarchy(instanceKlassHandle k, TRAPS);
   // event based tracing
   static void post_class_load_event(const Ticks& start_time, instanceKlassHandle k,
                                     Handle initiating_loader);
   // We pass in the hashtable index so we can calculate it outside of
   // the SystemDictionary_lock.
   // Basic find on loaded classes
   static Klass* find_class(int index, unsigned int hash,
                              Symbol* name, ClassLoaderData* loader_data);
   static Klass* find_class(Symbol* class_name, ClassLoaderData* loader_data);
   // Basic find on classes in the midst of being loaded
   static Symbol* find_placeholder(Symbol* name, ClassLoaderData* loader_data);
   // Updating entry in dictionary
   // Add a completely loaded class
   static void add_klass(int index, Symbol* class_name,
                         ClassLoaderData* loader_data, KlassHandle obj);
   // Add a placeholder for a class being loaded
   static void add_placeholder(int index,
                               Symbol* class_name,
                               ClassLoaderData* loader_data);
   static void remove_placeholder(int index,
                                  Symbol* class_name,
                                  ClassLoaderData* loader_data);
   // Performs cleanups after resolve_super_or_fail. This typically needs
   // to be called on failure.
   // Won't throw, but can block.
   static void resolution_cleanups(Symbol* class_name,
                                   ClassLoaderData* loader_data,
                                   TRAPS);
   // Initialization
   static void initialize_preloaded_classes(TRAPS);
   // Class loader constraints
   static void check_constraints(int index, unsigned int hash,
                                 instanceKlassHandle k, Handle loader,
                                 bool defining, TRAPS);
   static void update_dictionary(int d_index, unsigned int d_hash,
                                 int p_index, unsigned int p_hash,
                                 instanceKlassHandle k, Handle loader,
                                 TRAPS);
   // Variables holding commonly used klasses (preloaded)
   static Klass* _well_known_klasses[];
   // Lazily loaded klasses
   static Klass* volatile _abstract_ownable_synchronizer_klass;
   // table of box klasses (int_klass, etc.)
   static Klass* _box_klasses[T_VOID+1];
   static oop  _java_system_loader;
   static bool _has_loadClassInternal;
   static bool _has_checkPackageAccess;
 };
 #endif // SHARE_VM_CLASSFILE_SYSTEMDICTIONARY_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/classfile/systemDictionary.hpp@2c6ef90f030a (annotated)

src/share/vm/classfile/systemDictionary.hpp