--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/classfile/systemDictionary.cpp Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,2473 @@
+/*
+ * Copyright 1997-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+# include "incls/_precompiled.incl"
+# include "incls/_systemDictionary.cpp.incl"
+
+
+Dictionary* SystemDictionary::_dictionary = NULL;
+PlaceholderTable* SystemDictionary::_placeholders = NULL;
+Dictionary* SystemDictionary::_shared_dictionary = NULL;
+LoaderConstraintTable* SystemDictionary::_loader_constraints = NULL;
+ResolutionErrorTable* SystemDictionary::_resolution_errors = NULL;
+
+
+int SystemDictionary::_number_of_modifications = 0;
+
+oop SystemDictionary::_system_loader_lock_obj = NULL;
+
+klassOop SystemDictionary::_object_klass = NULL;
+klassOop SystemDictionary::_string_klass = NULL;
+klassOop SystemDictionary::_class_klass = NULL;
+klassOop SystemDictionary::_cloneable_klass = NULL;
+klassOop SystemDictionary::_classloader_klass = NULL;
+klassOop SystemDictionary::_serializable_klass = NULL;
+klassOop SystemDictionary::_system_klass = NULL;
+
+klassOop SystemDictionary::_throwable_klass = NULL;
+klassOop SystemDictionary::_error_klass = NULL;
+klassOop SystemDictionary::_threaddeath_klass = NULL;
+klassOop SystemDictionary::_exception_klass = NULL;
+klassOop SystemDictionary::_runtime_exception_klass = NULL;
+klassOop SystemDictionary::_classNotFoundException_klass = NULL;
+klassOop SystemDictionary::_noClassDefFoundError_klass = NULL;
+klassOop SystemDictionary::_linkageError_klass = NULL;
+klassOop SystemDictionary::_classCastException_klass = NULL;
+klassOop SystemDictionary::_arrayStoreException_klass = NULL;
+klassOop SystemDictionary::_virtualMachineError_klass = NULL;
+klassOop SystemDictionary::_outOfMemoryError_klass = NULL;
+klassOop SystemDictionary::_StackOverflowError_klass = NULL;
+klassOop SystemDictionary::_illegalMonitorStateException_klass = NULL;
+klassOop SystemDictionary::_protectionDomain_klass = NULL;
+klassOop SystemDictionary::_AccessControlContext_klass = NULL;
+
+klassOop SystemDictionary::_reference_klass = NULL;
+klassOop SystemDictionary::_soft_reference_klass = NULL;
+klassOop SystemDictionary::_weak_reference_klass = NULL;
+klassOop SystemDictionary::_final_reference_klass = NULL;
+klassOop SystemDictionary::_phantom_reference_klass = NULL;
+klassOop SystemDictionary::_finalizer_klass = NULL;
+
+klassOop SystemDictionary::_thread_klass = NULL;
+klassOop SystemDictionary::_threadGroup_klass = NULL;
+klassOop SystemDictionary::_properties_klass = NULL;
+klassOop SystemDictionary::_reflect_accessible_object_klass = NULL;
+klassOop SystemDictionary::_reflect_field_klass = NULL;
+klassOop SystemDictionary::_reflect_method_klass = NULL;
+klassOop SystemDictionary::_reflect_constructor_klass = NULL;
+klassOop SystemDictionary::_reflect_magic_klass = NULL;
+klassOop SystemDictionary::_reflect_method_accessor_klass = NULL;
+klassOop SystemDictionary::_reflect_constructor_accessor_klass = NULL;
+klassOop SystemDictionary::_reflect_delegating_classloader_klass = NULL;
+klassOop SystemDictionary::_reflect_constant_pool_klass = NULL;
+klassOop SystemDictionary::_reflect_unsafe_static_field_accessor_impl_klass = NULL;
+
+klassOop SystemDictionary::_vector_klass = NULL;
+klassOop SystemDictionary::_hashtable_klass = NULL;
+klassOop SystemDictionary::_stringBuffer_klass = NULL;
+
+klassOop SystemDictionary::_stackTraceElement_klass = NULL;
+
+klassOop SystemDictionary::_java_nio_Buffer_klass = NULL;
+
+klassOop SystemDictionary::_sun_misc_AtomicLongCSImpl_klass = NULL;
+klassOop SystemDictionary::_sun_jkernel_DownloadManager_klass = NULL;
+
+klassOop SystemDictionary::_boolean_klass = NULL;
+klassOop SystemDictionary::_char_klass = NULL;
+klassOop SystemDictionary::_float_klass = NULL;
+klassOop SystemDictionary::_double_klass = NULL;
+klassOop SystemDictionary::_byte_klass = NULL;
+klassOop SystemDictionary::_short_klass = NULL;
+klassOop SystemDictionary::_int_klass = NULL;
+klassOop SystemDictionary::_long_klass = NULL;
+klassOop SystemDictionary::_box_klasses[T_VOID+1] = { NULL /*, NULL...*/ };
+
+oop SystemDictionary::_java_system_loader = NULL;
+
+bool SystemDictionary::_has_loadClassInternal = false;
+bool SystemDictionary::_has_checkPackageAccess = false;
+
+// lazily initialized klass variables
+volatile klassOop SystemDictionary::_abstract_ownable_synchronizer_klass = NULL;
+
+
+// ----------------------------------------------------------------------------
+// Java-level SystemLoader
+
+oop SystemDictionary::java_system_loader() {
+ return _java_system_loader;
+}
+
+void SystemDictionary::compute_java_system_loader(TRAPS) {
+ KlassHandle system_klass(THREAD, _classloader_klass);
+ JavaValue result(T_OBJECT);
+ JavaCalls::call_static(&result,
+ KlassHandle(THREAD, _classloader_klass),
+ vmSymbolHandles::getSystemClassLoader_name(),
+ vmSymbolHandles::void_classloader_signature(),
+ CHECK);
+
+ _java_system_loader = (oop)result.get_jobject();
+}
+
+
+// ----------------------------------------------------------------------------
+// debugging
+
+#ifdef ASSERT
+
+// return true if class_name contains no '.' (internal format is '/')
+bool SystemDictionary::is_internal_format(symbolHandle class_name) {
+ if (class_name.not_null()) {
+ ResourceMark rm;
+ char* name = class_name->as_C_string();
+ return strchr(name, '.') == NULL;
+ } else {
+ return true;
+ }
+}
+
+#endif
+
+// ----------------------------------------------------------------------------
+// Resolving of classes
+
+// Forwards to resolve_or_null
+
+klassOop SystemDictionary::resolve_or_fail(symbolHandle class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS) {
+ klassOop klass = resolve_or_null(class_name, class_loader, protection_domain, THREAD);
+ if (HAS_PENDING_EXCEPTION || klass == NULL) {
+ KlassHandle k_h(THREAD, klass);
+ // can return a null klass
+ klass = handle_resolution_exception(class_name, class_loader, protection_domain, throw_error, k_h, THREAD);
+ }
+ return klass;
+}
+
+klassOop SystemDictionary::handle_resolution_exception(symbolHandle class_name, Handle class_loader, Handle protection_domain, bool throw_error, KlassHandle klass_h, TRAPS) {
+ if (HAS_PENDING_EXCEPTION) {
+ // If we have a pending exception we forward it to the caller, unless throw_error is true,
+ // in which case we have to check whether the pending exception is a ClassNotFoundException,
+ // and if so convert it to a NoClassDefFoundError
+ // And chain the original ClassNotFoundException
+ if (throw_error && PENDING_EXCEPTION->is_a(SystemDictionary::classNotFoundException_klass())) {
+ ResourceMark rm(THREAD);
+ assert(klass_h() == NULL, "Should not have result with exception pending");
+ Handle e(THREAD, PENDING_EXCEPTION);
+ CLEAR_PENDING_EXCEPTION;
+ THROW_MSG_CAUSE_0(vmSymbols::java_lang_NoClassDefFoundError(), class_name->as_C_string(), e);
+ } else {
+ return NULL;
+ }
+ }
+ // Class not found, throw appropriate error or exception depending on value of throw_error
+ if (klass_h() == NULL) {
+ ResourceMark rm(THREAD);
+ if (throw_error) {
+ THROW_MSG_0(vmSymbols::java_lang_NoClassDefFoundError(), class_name->as_C_string());
+ } else {
+ THROW_MSG_0(vmSymbols::java_lang_ClassNotFoundException(), class_name->as_C_string());
+ }
+ }
+ return (klassOop)klass_h();
+}
+
+
+klassOop SystemDictionary::resolve_or_fail(symbolHandle class_name,
+ bool throw_error, TRAPS)
+{
+ return resolve_or_fail(class_name, Handle(), Handle(), throw_error, THREAD);
+}
+
+
+// Forwards to resolve_instance_class_or_null
+
+klassOop SystemDictionary::resolve_or_null(symbolHandle class_name, Handle class_loader, Handle protection_domain, TRAPS) {
+ assert(!THREAD->is_Compiler_thread(), "Can not load classes with the Compiler thread");
+ if (FieldType::is_array(class_name())) {
+ return resolve_array_class_or_null(class_name, class_loader, protection_domain, CHECK_NULL);
+ } else {
+ return resolve_instance_class_or_null(class_name, class_loader, protection_domain, CHECK_NULL);
+ }
+}
+
+klassOop SystemDictionary::resolve_or_null(symbolHandle class_name, TRAPS) {
+ return resolve_or_null(class_name, Handle(), Handle(), THREAD);
+}
+
+// Forwards to resolve_instance_class_or_null
+
+klassOop SystemDictionary::resolve_array_class_or_null(symbolHandle class_name,
+ Handle class_loader,
+ Handle protection_domain,
+ TRAPS) {
+ assert(FieldType::is_array(class_name()), "must be array");
+ jint dimension;
+ symbolOop object_key;
+ klassOop k = NULL;
+ // dimension and object_key are assigned as a side-effect of this call
+ BasicType t = FieldType::get_array_info(class_name(),
+ &dimension,
+ &object_key,
+ CHECK_NULL);
+
+ if (t == T_OBJECT) {
+ symbolHandle h_key(THREAD, object_key);
+ // naked oop "k" is OK here -- we assign back into it
+ k = SystemDictionary::resolve_instance_class_or_null(h_key,
+ class_loader,
+ protection_domain,
+ CHECK_NULL);
+ if (k != NULL) {
+ k = Klass::cast(k)->array_klass(dimension, CHECK_NULL);
+ }
+ } else {
+ k = Universe::typeArrayKlassObj(t);
+ k = typeArrayKlass::cast(k)->array_klass(dimension, CHECK_NULL);
+ }
+ return k;
+}
+
+
+// Must be called for any super-class or super-interface resolution
+// during class definition to allow class circularity checking
+// super-interface callers:
+// parse_interfaces - for defineClass & jvmtiRedefineClasses
+// super-class callers:
+// ClassFileParser - for defineClass & jvmtiRedefineClasses
+// load_shared_class - while loading a class from shared archive
+// resolve_instance_class_or_fail:
+// when resolving a class that has an existing placeholder with
+// a saved superclass [i.e. a defineClass is currently in progress]
+// if another thread is trying to resolve the class, it must do
+// super-class checks on its own thread to catch class circularity
+// This last call is critical in class circularity checking for cases
+// where classloading is delegated to different threads and the
+// classloader lock is released.
+// Take the case: Base->Super->Base
+// 1. If thread T1 tries to do a defineClass of class Base
+// resolve_super_or_fail creates placeholder: T1, Base (super Super)
+// 2. resolve_instance_class_or_null does not find SD or placeholder for Super
+// so it tries to load Super
+// 3. If we load the class internally, or user classloader uses same thread
+// loadClassFromxxx or defineClass via parseClassFile Super ...
+// 3.1 resolve_super_or_fail creates placeholder: T1, Super (super Base)
+// 3.3 resolve_instance_class_or_null Base, finds placeholder for Base
+// 3.4 calls resolve_super_or_fail Base
+// 3.5 finds T1,Base -> throws class circularity
+//OR 4. If T2 tries to resolve Super via defineClass Super ...
+// 4.1 resolve_super_or_fail creates placeholder: T2, Super (super Base)
+// 4.2 resolve_instance_class_or_null Base, finds placeholder for Base (super Super)
+// 4.3 calls resolve_super_or_fail Super in parallel on own thread T2
+// 4.4 finds T2, Super -> throws class circularity
+// Must be called, even if superclass is null, since this is
+// where the placeholder entry is created which claims this
+// thread is loading this class/classloader.
+klassOop SystemDictionary::resolve_super_or_fail(symbolHandle child_name,
+ symbolHandle class_name,
+ Handle class_loader,
+ Handle protection_domain,
+ bool is_superclass,
+ TRAPS) {
+
+ // Double-check, if child class is already loaded, just return super-class,interface
+ // Don't add a placedholder if already loaded, i.e. already in system dictionary
+ // Make sure there's a placeholder for the *child* before resolving.
+ // Used as a claim that this thread is currently loading superclass/classloader
+ // Used here for ClassCircularity checks and also for heap verification
+ // (every instanceKlass in the heap needs to be in the system dictionary
+ // or have a placeholder).
+ // Must check ClassCircularity before checking if super class is already loaded
+ //
+ // We might not already have a placeholder if this child_name was
+ // first seen via resolve_from_stream (jni_DefineClass or JVM_DefineClass);
+ // the name of the class might not be known until the stream is actually
+ // parsed.
+ // Bugs 4643874, 4715493
+ // compute_hash can have a safepoint
+
+ unsigned int d_hash = dictionary()->compute_hash(child_name, class_loader);
+ int d_index = dictionary()->hash_to_index(d_hash);
+ unsigned int p_hash = placeholders()->compute_hash(child_name, class_loader);
+ int p_index = placeholders()->hash_to_index(p_hash);
+ // can't throw error holding a lock
+ bool child_already_loaded = false;
+ bool throw_circularity_error = false;
+ {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ klassOop childk = find_class(d_index, d_hash, child_name, class_loader);
+ klassOop quicksuperk;
+ // to support // loading: if child done loading, just return superclass
+ // if class_name, & class_loader don't match:
+ // if initial define, SD update will give LinkageError
+ // if redefine: compare_class_versions will give HIERARCHY_CHANGED
+ // so we don't throw an exception here.
+ // see: nsk redefclass014 & java.lang.instrument Instrument032
+ if ((childk != NULL ) && (is_superclass) &&
+ ((quicksuperk = instanceKlass::cast(childk)->super()) != NULL) &&
+
+ ((Klass::cast(quicksuperk)->name() == class_name()) &&
+ (Klass::cast(quicksuperk)->class_loader() == class_loader()))) {
+ return quicksuperk;
+ } else {
+ PlaceholderEntry* probe = placeholders()->get_entry(p_index, p_hash, child_name, class_loader);
+ if (probe && probe->check_seen_thread(THREAD, PlaceholderTable::LOAD_SUPER)) {
+ throw_circularity_error = true;
+ }
+
+ // add placeholder entry even if error - callers will remove on error
+ PlaceholderEntry* newprobe = placeholders()->find_and_add(p_index, p_hash, child_name, class_loader, PlaceholderTable::LOAD_SUPER, class_name, THREAD);
+ if (throw_circularity_error) {
+ newprobe->remove_seen_thread(THREAD, PlaceholderTable::LOAD_SUPER);
+ }
+ }
+ }
+ if (throw_circularity_error) {
+ ResourceMark rm(THREAD);
+ THROW_MSG_0(vmSymbols::java_lang_ClassCircularityError(), child_name->as_C_string());
+ }
+
+// java.lang.Object should have been found above
+ assert(class_name() != NULL, "null super class for resolving");
+ // Resolve the super class or interface, check results on return
+ klassOop superk = NULL;
+ superk = SystemDictionary::resolve_or_null(class_name,
+ class_loader,
+ protection_domain,
+ THREAD);
+
+ KlassHandle superk_h(THREAD, superk);
+
+ // Note: clean up of placeholders currently in callers of
+ // resolve_super_or_fail - either at update_dictionary time
+ // or on error
+ {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ PlaceholderEntry* probe = placeholders()->get_entry(p_index, p_hash, child_name, class_loader);
+ if (probe != NULL) {
+ probe->remove_seen_thread(THREAD, PlaceholderTable::LOAD_SUPER);
+ }
+ }
+ if (HAS_PENDING_EXCEPTION || superk_h() == NULL) {
+ // can null superk
+ superk_h = KlassHandle(THREAD, handle_resolution_exception(class_name, class_loader, protection_domain, true, superk_h, THREAD));
+ }
+
+ return superk_h();
+}
+
+
+void SystemDictionary::validate_protection_domain(instanceKlassHandle klass,
+ Handle class_loader,
+ Handle protection_domain,
+ TRAPS) {
+ if(!has_checkPackageAccess()) return;
+
+ // Now we have to call back to java to check if the initating class has access
+ JavaValue result(T_VOID);
+ if (TraceProtectionDomainVerification) {
+ // Print out trace information
+ tty->print_cr("Checking package access");
+ tty->print(" - class loader: "); class_loader()->print_value_on(tty); tty->cr();
+ tty->print(" - protection domain: "); protection_domain()->print_value_on(tty); tty->cr();
+ tty->print(" - loading: "); klass()->print_value_on(tty); tty->cr();
+ }
+
+ assert(class_loader() != NULL, "should not have non-null protection domain for null classloader");
+
+ KlassHandle system_loader(THREAD, SystemDictionary::classloader_klass());
+ JavaCalls::call_special(&result,
+ class_loader,
+ system_loader,
+ vmSymbolHandles::checkPackageAccess_name(),
+ vmSymbolHandles::class_protectiondomain_signature(),
+ Handle(THREAD, klass->java_mirror()),
+ protection_domain,
+ THREAD);
+
+ if (TraceProtectionDomainVerification) {
+ if (HAS_PENDING_EXCEPTION) {
+ tty->print_cr(" -> DENIED !!!!!!!!!!!!!!!!!!!!!");
+ } else {
+ tty->print_cr(" -> granted");
+ }
+ tty->cr();
+ }
+
+ if (HAS_PENDING_EXCEPTION) return;
+
+ // If no exception has been thrown, we have validated the protection domain
+ // Insert the protection domain of the initiating class into the set.
+ {
+ // We recalculate the entry here -- we've called out to java since
+ // the last time it was calculated.
+ symbolHandle kn(THREAD, klass->name());
+ unsigned int d_hash = dictionary()->compute_hash(kn, class_loader);
+ int d_index = dictionary()->hash_to_index(d_hash);
+
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ {
+ // Note that we have an entry, and entries can be deleted only during GC,
+ // so we cannot allow GC to occur while we're holding this entry.
+
+ // We're using a No_Safepoint_Verifier to catch any place where we
+ // might potentially do a GC at all.
+ // SystemDictionary::do_unloading() asserts that classes are only
+ // unloaded at a safepoint.
+ No_Safepoint_Verifier nosafepoint;
+ dictionary()->add_protection_domain(d_index, d_hash, klass, class_loader,
+ protection_domain, THREAD);
+ }
+ }
+}
+
+// We only get here if this thread finds that another thread
+// has already claimed the placeholder token for the current operation,
+// but that other thread either never owned or gave up the
+// object lock
+// Waits on SystemDictionary_lock to indicate placeholder table updated
+// On return, caller must recheck placeholder table state
+//
+// We only get here if
+// 1) custom classLoader, i.e. not bootstrap classloader
+// 2) UnsyncloadClass not set
+// 3) custom classLoader has broken the class loader objectLock
+// so another thread got here in parallel
+//
+// lockObject must be held.
+// Complicated dance due to lock ordering:
+// Must first release the classloader object lock to
+// allow initial definer to complete the class definition
+// and to avoid deadlock
+// Reclaim classloader lock object with same original recursion count
+// Must release SystemDictionary_lock after notify, since
+// class loader lock must be claimed before SystemDictionary_lock
+// to prevent deadlocks
+//
+// The notify allows applications that did an untimed wait() on
+// the classloader object lock to not hang.
+void SystemDictionary::double_lock_wait(Handle lockObject, TRAPS) {
+ assert_lock_strong(SystemDictionary_lock);
+
+ bool calledholdinglock
+ = ObjectSynchronizer::current_thread_holds_lock((JavaThread*)THREAD, lockObject);
+ assert(calledholdinglock,"must hold lock for notify");
+ assert(!UnsyncloadClass, "unexpected double_lock_wait");
+ ObjectSynchronizer::notifyall(lockObject, THREAD);
+ intptr_t recursions = ObjectSynchronizer::complete_exit(lockObject, THREAD);
+ SystemDictionary_lock->wait();
+ SystemDictionary_lock->unlock();
+ ObjectSynchronizer::reenter(lockObject, recursions, THREAD);
+ SystemDictionary_lock->lock();
+}
+
+// If the class in is in the placeholder table, class loading is in progress
+// For cases where the application changes threads to load classes, it
+// is critical to ClassCircularity detection that we try loading
+// the superclass on the same thread internally, so we do parallel
+// super class loading here.
+// This also is critical in cases where the original thread gets stalled
+// even in non-circularity situations.
+// Note: only one thread can define the class, but multiple can resolve
+// Note: must call resolve_super_or_fail even if null super -
+// to force placeholder entry creation for this class
+// Caller must check for pending exception
+// Returns non-null klassOop if other thread has completed load
+// and we are done,
+// If return null klassOop and no pending exception, the caller must load the class
+instanceKlassHandle SystemDictionary::handle_parallel_super_load(
+ symbolHandle name, symbolHandle superclassname, Handle class_loader,
+ Handle protection_domain, Handle lockObject, TRAPS) {
+
+ instanceKlassHandle nh = instanceKlassHandle(); // null Handle
+ unsigned int d_hash = dictionary()->compute_hash(name, class_loader);
+ int d_index = dictionary()->hash_to_index(d_hash);
+ unsigned int p_hash = placeholders()->compute_hash(name, class_loader);
+ int p_index = placeholders()->hash_to_index(p_hash);
+
+ // superk is not used, resolve_super called for circularity check only
+ // This code is reached in two situations. One if this thread
+ // is loading the same class twice (e.g. ClassCircularity, or
+ // java.lang.instrument).
+ // The second is if another thread started the resolve_super first
+ // and has not yet finished.
+ // In both cases the original caller will clean up the placeholder
+ // entry on error.
+ klassOop superk = SystemDictionary::resolve_super_or_fail(name,
+ superclassname,
+ class_loader,
+ protection_domain,
+ true,
+ CHECK_(nh));
+ // We don't redefine the class, so we just need to clean up if there
+ // was not an error (don't want to modify any system dictionary
+ // data structures).
+ {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ placeholders()->find_and_remove(p_index, p_hash, name, class_loader, THREAD);
+ SystemDictionary_lock->notify_all();
+ }
+
+ // UnsyncloadClass does NOT wait for parallel superclass loads to complete
+ // Bootstrap classloader does wait for parallel superclass loads
+ if (UnsyncloadClass) {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ // Check if classloading completed while we were loading superclass or waiting
+ klassOop check = find_class(d_index, d_hash, name, class_loader);
+ if (check != NULL) {
+ // Klass is already loaded, so just return it
+ return(instanceKlassHandle(THREAD, check));
+ } else {
+ return nh;
+ }
+ }
+
+ // must loop to both handle other placeholder updates
+ // and spurious notifications
+ bool super_load_in_progress = true;
+ PlaceholderEntry* placeholder;
+ while (super_load_in_progress) {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ // Check if classloading completed while we were loading superclass or waiting
+ klassOop check = find_class(d_index, d_hash, name, class_loader);
+ if (check != NULL) {
+ // Klass is already loaded, so just return it
+ return(instanceKlassHandle(THREAD, check));
+ } else {
+ placeholder = placeholders()->get_entry(p_index, p_hash, name, class_loader);
+ if (placeholder && placeholder->super_load_in_progress() ){
+ // Before UnsyncloadClass:
+ // We only get here if the application has released the
+ // classloader lock when another thread was in the middle of loading a
+ // superclass/superinterface for this class, and now
+ // this thread is also trying to load this class.
+ // To minimize surprises, the first thread that started to
+ // load a class should be the one to complete the loading
+ // with the classfile it initially expected.
+ // This logic has the current thread wait once it has done
+ // all the superclass/superinterface loading it can, until
+ // the original thread completes the class loading or fails
+ // If it completes we will use the resulting instanceKlass
+ // which we will find below in the systemDictionary.
+ // We also get here for parallel bootstrap classloader
+ if (class_loader.is_null()) {
+ SystemDictionary_lock->wait();
+ } else {
+ double_lock_wait(lockObject, THREAD);
+ }
+ } else {
+ // If not in SD and not in PH, other thread's load must have failed
+ super_load_in_progress = false;
+ }
+ }
+ }
+ return (nh);
+}
+
+
+klassOop SystemDictionary::resolve_instance_class_or_null(symbolHandle class_name, Handle class_loader, Handle protection_domain, TRAPS) {
+ assert(class_name.not_null() && !FieldType::is_array(class_name()), "invalid class name");
+ // First check to see if we should remove wrapping L and ;
+ symbolHandle name;
+ if (FieldType::is_obj(class_name())) {
+ ResourceMark rm(THREAD);
+ // Ignore wrapping L and ;.
+ name = oopFactory::new_symbol_handle(class_name()->as_C_string() + 1, class_name()->utf8_length() - 2, CHECK_NULL);
+ } else {
+ name = class_name;
+ }
+
+ // UseNewReflection
+ // Fix for 4474172; see evaluation for more details
+ class_loader = Handle(THREAD, java_lang_ClassLoader::non_reflection_class_loader(class_loader()));
+
+ // Do lookup to see if class already exist and the protection domain
+ // has the right access
+ unsigned int d_hash = dictionary()->compute_hash(name, class_loader);
+ int d_index = dictionary()->hash_to_index(d_hash);
+ klassOop probe = dictionary()->find(d_index, d_hash, name, class_loader,
+ protection_domain, THREAD);
+ if (probe != NULL) return probe;
+
+
+ // Non-bootstrap class loaders will call out to class loader and
+ // define via jvm/jni_DefineClass which will acquire the
+ // class loader object lock to protect against multiple threads
+ // defining the class in parallel by accident.
+ // This lock must be acquired here so the waiter will find
+ // any successful result in the SystemDictionary and not attempt
+ // the define
+ // Classloaders that support parallelism, e.g. bootstrap classloader,
+ // or all classloaders with UnsyncloadClass do not acquire lock here
+ bool DoObjectLock = true;
+ if (UnsyncloadClass || (class_loader.is_null())) {
+ DoObjectLock = false;
+ }
+
+ unsigned int p_hash = placeholders()->compute_hash(name, class_loader);
+ int p_index = placeholders()->hash_to_index(p_hash);
+
+ // Class is not in SystemDictionary so we have to do loading.
+ // Make sure we are synchronized on the class loader before we proceed
+ Handle lockObject = compute_loader_lock_object(class_loader, THREAD);
+ check_loader_lock_contention(lockObject, THREAD);
+ ObjectLocker ol(lockObject, THREAD, DoObjectLock);
+
+ // Check again (after locking) if class already exist in SystemDictionary
+ bool class_has_been_loaded = false;
+ bool super_load_in_progress = false;
+ bool havesupername = false;
+ instanceKlassHandle k;
+ PlaceholderEntry* placeholder;
+ symbolHandle superclassname;
+
+ {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ klassOop check = find_class(d_index, d_hash, name, class_loader);
+ if (check != NULL) {
+ // Klass is already loaded, so just return it
+ class_has_been_loaded = true;
+ k = instanceKlassHandle(THREAD, check);
+ } else {
+ placeholder = placeholders()->get_entry(p_index, p_hash, name, class_loader);
+ if (placeholder && placeholder->super_load_in_progress()) {
+ super_load_in_progress = true;
+ if (placeholder->havesupername() == true) {
+ superclassname = symbolHandle(THREAD, placeholder->supername());
+ havesupername = true;
+ }
+ }
+ }
+ }
+
+ // If the class in is in the placeholder table, class loading is in progress
+ if (super_load_in_progress && havesupername==true) {
+ k = SystemDictionary::handle_parallel_super_load(name, superclassname,
+ class_loader, protection_domain, lockObject, THREAD);
+ if (HAS_PENDING_EXCEPTION) {
+ return NULL;
+ }
+ if (!k.is_null()) {
+ class_has_been_loaded = true;
+ }
+ }
+
+ if (!class_has_been_loaded) {
+
+ // add placeholder entry to record loading instance class
+ // Five cases:
+ // All cases need to prevent modifying bootclasssearchpath
+ // in parallel with a classload of same classname
+ // case 1. traditional classloaders that rely on the classloader object lock
+ // - no other need for LOAD_INSTANCE
+ // case 2. traditional classloaders that break the classloader object lock
+ // as a deadlock workaround. Detection of this case requires that
+ // this check is done while holding the classloader object lock,
+ // and that lock is still held when calling classloader's loadClass.
+ // For these classloaders, we ensure that the first requestor
+ // completes the load and other requestors wait for completion.
+ // case 3. UnsyncloadClass - don't use objectLocker
+ // With this flag, we allow parallel classloading of a
+ // class/classloader pair
+ // case4. Bootstrap classloader - don't own objectLocker
+ // This classloader supports parallelism at the classloader level,
+ // but only allows a single load of a class/classloader pair.
+ // No performance benefit and no deadlock issues.
+ // case 5. Future: parallel user level classloaders - without objectLocker
+ symbolHandle nullsymbolHandle;
+ bool throw_circularity_error = false;
+ {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ if (!UnsyncloadClass) {
+ PlaceholderEntry* oldprobe = placeholders()->get_entry(p_index, p_hash, name, class_loader);
+ if (oldprobe) {
+ // only need check_seen_thread once, not on each loop
+ // 6341374 java/lang/Instrument with -Xcomp
+ if (oldprobe->check_seen_thread(THREAD, PlaceholderTable::LOAD_INSTANCE)) {
+ throw_circularity_error = true;
+ } else {
+ // case 1: traditional: should never see load_in_progress.
+ while (!class_has_been_loaded && oldprobe && oldprobe->instance_load_in_progress()) {
+
+ // case 4: bootstrap classloader: prevent futile classloading,
+ // wait on first requestor
+ if (class_loader.is_null()) {
+ SystemDictionary_lock->wait();
+ } else {
+ // case 2: traditional with broken classloader lock. wait on first
+ // requestor.
+ double_lock_wait(lockObject, THREAD);
+ }
+ // Check if classloading completed while we were waiting
+ klassOop check = find_class(d_index, d_hash, name, class_loader);
+ if (check != NULL) {
+ // Klass is already loaded, so just return it
+ k = instanceKlassHandle(THREAD, check);
+ class_has_been_loaded = true;
+ }
+ // check if other thread failed to load and cleaned up
+ oldprobe = placeholders()->get_entry(p_index, p_hash, name, class_loader);
+ }
+ }
+ }
+ }
+ // All cases: add LOAD_INSTANCE
+ // case 3: UnsyncloadClass: allow competing threads to try
+ // LOAD_INSTANCE in parallel
+ // add placeholder entry even if error - callers will remove on error
+ if (!class_has_been_loaded) {
+ PlaceholderEntry* newprobe = placeholders()->find_and_add(p_index, p_hash, name, class_loader, PlaceholderTable::LOAD_INSTANCE, nullsymbolHandle, THREAD);
+ if (throw_circularity_error) {
+ newprobe->remove_seen_thread(THREAD, PlaceholderTable::LOAD_INSTANCE);
+ }
+ // For class loaders that do not acquire the classloader object lock,
+ // if they did not catch another thread holding LOAD_INSTANCE,
+ // need a check analogous to the acquire ObjectLocker/find_class
+ // i.e. now that we hold the LOAD_INSTANCE token on loading this class/CL
+ // one final check if the load has already completed
+ klassOop check = find_class(d_index, d_hash, name, class_loader);
+ if (check != NULL) {
+ // Klass is already loaded, so just return it
+ k = instanceKlassHandle(THREAD, check);
+ class_has_been_loaded = true;
+ newprobe->remove_seen_thread(THREAD, PlaceholderTable::LOAD_INSTANCE);
+ }
+ }
+ }
+ // must throw error outside of owning lock
+ if (throw_circularity_error) {
+ ResourceMark rm(THREAD);
+ THROW_MSG_0(vmSymbols::java_lang_ClassCircularityError(), name->as_C_string());
+ }
+
+ if (!class_has_been_loaded) {
+
+ // Do actual loading
+ k = load_instance_class(name, class_loader, THREAD);
+
+ // In custom class loaders, the usual findClass calls
+ // findLoadedClass, which directly searches the SystemDictionary, then
+ // defineClass. If these are not atomic with respect to other threads,
+ // the findLoadedClass can fail, but the defineClass can get a
+ // LinkageError:: duplicate class definition.
+ // If they got a linkageError, check if a parallel class load succeeded.
+ // If it did, then for bytecode resolution the specification requires
+ // that we return the same result we did for the other thread, i.e. the
+ // successfully loaded instanceKlass
+ // Note: Class can not be unloaded as long as any classloader refs exist
+ // Should not get here for classloaders that support parallelism
+ // with the new cleaner mechanism, e.g. bootstrap classloader
+ if (UnsyncloadClass || (class_loader.is_null())) {
+ if (k.is_null() && HAS_PENDING_EXCEPTION
+ && PENDING_EXCEPTION->is_a(SystemDictionary::linkageError_klass())) {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ klassOop check = find_class(d_index, d_hash, name, class_loader);
+ if (check != NULL) {
+ // Klass is already loaded, so just use it
+ k = instanceKlassHandle(THREAD, check);
+ CLEAR_PENDING_EXCEPTION;
+ guarantee((!class_loader.is_null()), "dup definition for bootstrap loader?");
+ }
+ }
+ }
+
+ // clean up placeholder entries for success or error
+ // This cleans up LOAD_INSTANCE entries
+ // It also cleans up LOAD_SUPER entries on errors from
+ // calling load_instance_class
+ {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ PlaceholderEntry* probe = placeholders()->get_entry(p_index, p_hash, name, class_loader);
+ if (probe != NULL) {
+ probe->remove_seen_thread(THREAD, PlaceholderTable::LOAD_INSTANCE);
+ placeholders()->find_and_remove(p_index, p_hash, name, class_loader, THREAD);
+ SystemDictionary_lock->notify_all();
+ }
+ }
+
+ // If everything was OK (no exceptions, no null return value), and
+ // class_loader is NOT the defining loader, do a little more bookkeeping.
+ if (!HAS_PENDING_EXCEPTION && !k.is_null() &&
+ k->class_loader() != class_loader()) {
+
+ check_constraints(d_index, d_hash, k, class_loader, false, THREAD);
+
+ // Need to check for a PENDING_EXCEPTION again; check_constraints
+ // can throw and doesn't use the CHECK macro.
+ if (!HAS_PENDING_EXCEPTION) {
+ { // Grabbing the Compile_lock prevents systemDictionary updates
+ // during compilations.
+ MutexLocker mu(Compile_lock, THREAD);
+ update_dictionary(d_index, d_hash, p_index, p_hash,
+ k, class_loader, THREAD);
+ }
+ if (JvmtiExport::should_post_class_load()) {
+ Thread *thread = THREAD;
+ assert(thread->is_Java_thread(), "thread->is_Java_thread()");
+ JvmtiExport::post_class_load((JavaThread *) thread, k());
+ }
+ }
+ }
+ if (HAS_PENDING_EXCEPTION || k.is_null()) {
+ // On error, clean up placeholders
+ {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ placeholders()->find_and_remove(p_index, p_hash, name, class_loader, THREAD);
+ SystemDictionary_lock->notify_all();
+ }
+ return NULL;
+ }
+ }
+ }
+
+#ifdef ASSERT
+ {
+ Handle loader (THREAD, k->class_loader());
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ oop kk = find_class_or_placeholder(name, loader);
+ assert(kk == k(), "should be present in dictionary");
+ }
+#endif
+
+ // return if the protection domain in NULL
+ if (protection_domain() == NULL) return k();
+
+ // Check the protection domain has the right access
+ {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ // Note that we have an entry, and entries can be deleted only during GC,
+ // so we cannot allow GC to occur while we're holding this entry.
+ // We're using a No_Safepoint_Verifier to catch any place where we
+ // might potentially do a GC at all.
+ // SystemDictionary::do_unloading() asserts that classes are only
+ // unloaded at a safepoint.
+ No_Safepoint_Verifier nosafepoint;
+ if (dictionary()->is_valid_protection_domain(d_index, d_hash, name,
+ class_loader,
+ protection_domain)) {
+ return k();
+ }
+ }
+
+ // Verify protection domain. If it fails an exception is thrown
+ validate_protection_domain(k, class_loader, protection_domain, CHECK_(klassOop(NULL)));
+
+ return k();
+}
+
+
+// This routine does not lock the system dictionary.
+//
+// Since readers don't hold a lock, we must make sure that system
+// dictionary entries are only removed at a safepoint (when only one
+// thread is running), and are added to in a safe way (all links must
+// be updated in an MT-safe manner).
+//
+// Callers should be aware that an entry could be added just after
+// _dictionary->bucket(index) is read here, so the caller will not see
+// the new entry.
+
+klassOop SystemDictionary::find(symbolHandle class_name,
+ Handle class_loader,
+ Handle protection_domain,
+ TRAPS) {
+
+ unsigned int d_hash = dictionary()->compute_hash(class_name, class_loader);
+ int d_index = dictionary()->hash_to_index(d_hash);
+
+ {
+ // Note that we have an entry, and entries can be deleted only during GC,
+ // so we cannot allow GC to occur while we're holding this entry.
+ // We're using a No_Safepoint_Verifier to catch any place where we
+ // might potentially do a GC at all.
+ // SystemDictionary::do_unloading() asserts that classes are only
+ // unloaded at a safepoint.
+ No_Safepoint_Verifier nosafepoint;
+ return dictionary()->find(d_index, d_hash, class_name, class_loader,
+ protection_domain, THREAD);
+ }
+}
+
+
+// Look for a loaded instance or array klass by name. Do not do any loading.
+// return NULL in case of error.
+klassOop SystemDictionary::find_instance_or_array_klass(symbolHandle class_name,
+ Handle class_loader,
+ Handle protection_domain,
+ TRAPS) {
+ klassOop k = NULL;
+ assert(class_name() != NULL, "class name must be non NULL");
+ if (FieldType::is_array(class_name())) {
+ // The name refers to an array. Parse the name.
+ jint dimension;
+ symbolOop object_key;
+
+ // dimension and object_key are assigned as a side-effect of this call
+ BasicType t = FieldType::get_array_info(class_name(), &dimension,
+ &object_key, CHECK_(NULL));
+ if (t != T_OBJECT) {
+ k = Universe::typeArrayKlassObj(t);
+ } else {
+ symbolHandle h_key(THREAD, object_key);
+ k = SystemDictionary::find(h_key, class_loader, protection_domain, THREAD);
+ }
+ if (k != NULL) {
+ k = Klass::cast(k)->array_klass_or_null(dimension);
+ }
+ } else {
+ k = find(class_name, class_loader, protection_domain, THREAD);
+ }
+ return k;
+}
+
+// Note: this method is much like resolve_from_stream, but
+// updates no supplemental data structures.
+// TODO consolidate the two methods with a helper routine?
+klassOop SystemDictionary::parse_stream(symbolHandle class_name,
+ Handle class_loader,
+ Handle protection_domain,
+ ClassFileStream* st,
+ TRAPS) {
+ symbolHandle parsed_name;
+
+ // Parse the stream. Note that we do this even though this klass might
+ // already be present in the SystemDictionary, otherwise we would not
+ // throw potential ClassFormatErrors.
+ //
+ // Note: "name" is updated.
+ // Further note: a placeholder will be added for this class when
+ // super classes are loaded (resolve_super_or_fail). We expect this
+ // to be called for all classes but java.lang.Object; and we preload
+ // java.lang.Object through resolve_or_fail, not this path.
+
+ instanceKlassHandle k = ClassFileParser(st).parseClassFile(class_name,
+ class_loader,
+ protection_domain,
+ parsed_name,
+ THREAD);
+
+
+ // We don't redefine the class, so we just need to clean up whether there
+ // was an error or not (don't want to modify any system dictionary
+ // data structures).
+ // Parsed name could be null if we threw an error before we got far
+ // enough along to parse it -- in that case, there is nothing to clean up.
+ if (!parsed_name.is_null()) {
+ unsigned int p_hash = placeholders()->compute_hash(parsed_name,
+ class_loader);
+ int p_index = placeholders()->hash_to_index(p_hash);
+ {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ placeholders()->find_and_remove(p_index, p_hash, parsed_name, class_loader, THREAD);
+ SystemDictionary_lock->notify_all();
+ }
+ }
+
+ return k();
+}
+
+// Add a klass to the system from a stream (called by jni_DefineClass and
+// JVM_DefineClass).
+// Note: class_name can be NULL. In that case we do not know the name of
+// the class until we have parsed the stream.
+
+klassOop SystemDictionary::resolve_from_stream(symbolHandle class_name,
+ Handle class_loader,
+ Handle protection_domain,
+ ClassFileStream* st,
+ TRAPS) {
+
+ // Make sure we are synchronized on the class loader before we initiate
+ // loading.
+ Handle lockObject = compute_loader_lock_object(class_loader, THREAD);
+ check_loader_lock_contention(lockObject, THREAD);
+ ObjectLocker ol(lockObject, THREAD);
+
+ symbolHandle parsed_name;
+
+ // Parse the stream. Note that we do this even though this klass might
+ // already be present in the SystemDictionary, otherwise we would not
+ // throw potential ClassFormatErrors.
+ //
+ // Note: "name" is updated.
+ // Further note: a placeholder will be added for this class when
+ // super classes are loaded (resolve_super_or_fail). We expect this
+ // to be called for all classes but java.lang.Object; and we preload
+ // java.lang.Object through resolve_or_fail, not this path.
+
+ instanceKlassHandle k = ClassFileParser(st).parseClassFile(class_name,
+ class_loader,
+ protection_domain,
+ parsed_name,
+ THREAD);
+
+ const char* pkg = "java/";
+ if (!HAS_PENDING_EXCEPTION &&
+ !class_loader.is_null() &&
+ !parsed_name.is_null() &&
+ !strncmp((const char*)parsed_name->bytes(), pkg, strlen(pkg))) {
+ // It is illegal to define classes in the "java." package from
+ // JVM_DefineClass or jni_DefineClass unless you're the bootclassloader
+ ResourceMark rm(THREAD);
+ char* name = parsed_name->as_C_string();
+ char* index = strrchr(name, '/');
+ *index = '\0'; // chop to just the package name
+ while ((index = strchr(name, '/')) != NULL) {
+ *index = '.'; // replace '/' with '.' in package name
+ }
+ const char* fmt = "Prohibited package name: %s";
+ size_t len = strlen(fmt) + strlen(name);
+ char* message = NEW_RESOURCE_ARRAY(char, len);
+ jio_snprintf(message, len, fmt, name);
+ Exceptions::_throw_msg(THREAD_AND_LOCATION,
+ vmSymbols::java_lang_SecurityException(), message);
+ }
+
+ if (!HAS_PENDING_EXCEPTION) {
+ assert(!parsed_name.is_null(), "Sanity");
+ assert(class_name.is_null() || class_name() == parsed_name(),
+ "name mismatch");
+ // Verification prevents us from creating names with dots in them, this
+ // asserts that that's the case.
+ assert(is_internal_format(parsed_name),
+ "external class name format used internally");
+
+ // Add class just loaded
+ define_instance_class(k, THREAD);
+ }
+
+ // If parsing the class file or define_instance_class failed, we
+ // need to remove the placeholder added on our behalf. But we
+ // must make sure parsed_name is valid first (it won't be if we had
+ // a format error before the class was parsed far enough to
+ // find the name).
+ if (HAS_PENDING_EXCEPTION && !parsed_name.is_null()) {
+ unsigned int p_hash = placeholders()->compute_hash(parsed_name,
+ class_loader);
+ int p_index = placeholders()->hash_to_index(p_hash);
+ {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ placeholders()->find_and_remove(p_index, p_hash, parsed_name, class_loader, THREAD);
+ SystemDictionary_lock->notify_all();
+ }
+ return NULL;
+ }
+
+ // Make sure that we didn't leave a place holder in the
+ // SystemDictionary; this is only done on success
+ debug_only( {
+ if (!HAS_PENDING_EXCEPTION) {
+ assert(!parsed_name.is_null(), "parsed_name is still null?");
+ symbolHandle h_name (THREAD, k->name());
+ Handle h_loader (THREAD, k->class_loader());
+
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+
+ oop check = find_class_or_placeholder(parsed_name, class_loader);
+ assert(check == k(), "should be present in the dictionary");
+
+ oop check2 = find_class_or_placeholder(h_name, h_loader);
+ assert(check == check2, "name inconsistancy in SystemDictionary");
+ }
+ } );
+
+ return k();
+}
+
+
+void SystemDictionary::set_shared_dictionary(HashtableBucket* t, int length,
+ int number_of_entries) {
+ assert(length == _nof_buckets * sizeof(HashtableBucket),
+ "bad shared dictionary size.");
+ _shared_dictionary = new Dictionary(_nof_buckets, t, number_of_entries);
+}
+
+
+// If there is a shared dictionary, then find the entry for the
+// given shared system class, if any.
+
+klassOop SystemDictionary::find_shared_class(symbolHandle class_name) {
+ if (shared_dictionary() != NULL) {
+ unsigned int d_hash = dictionary()->compute_hash(class_name, Handle());
+ int d_index = dictionary()->hash_to_index(d_hash);
+ return shared_dictionary()->find_shared_class(d_index, d_hash, class_name);
+ } else {
+ return NULL;
+ }
+}
+
+
+// Load a class from the shared spaces (found through the shared system
+// dictionary). Force the superclass and all interfaces to be loaded.
+// Update the class definition to include sibling classes and no
+// subclasses (yet). [Classes in the shared space are not part of the
+// object hierarchy until loaded.]
+
+instanceKlassHandle SystemDictionary::load_shared_class(
+ symbolHandle class_name, Handle class_loader, TRAPS) {
+ instanceKlassHandle ik (THREAD, find_shared_class(class_name));
+ return load_shared_class(ik, class_loader, THREAD);
+}
+
+// Note well! Changes to this method may affect oop access order
+// in the shared archive. Please take care to not make changes that
+// adversely affect cold start time by changing the oop access order
+// that is specified in dump.cpp MarkAndMoveOrderedReadOnly and
+// MarkAndMoveOrderedReadWrite closures.
+instanceKlassHandle SystemDictionary::load_shared_class(
+ instanceKlassHandle ik, Handle class_loader, TRAPS) {
+ assert(class_loader.is_null(), "non-null classloader for shared class?");
+ if (ik.not_null()) {
+ instanceKlassHandle nh = instanceKlassHandle(); // null Handle
+ symbolHandle class_name(THREAD, ik->name());
+
+ // Found the class, now load the superclass and interfaces. If they
+ // are shared, add them to the main system dictionary and reset
+ // their hierarchy references (supers, subs, and interfaces).
+
+ if (ik->super() != NULL) {
+ symbolHandle cn(THREAD, ik->super()->klass_part()->name());
+ resolve_super_or_fail(class_name, cn,
+ class_loader, Handle(), true, CHECK_(nh));
+ }
+
+ objArrayHandle interfaces (THREAD, ik->local_interfaces());
+ int num_interfaces = interfaces->length();
+ for (int index = 0; index < num_interfaces; index++) {
+ klassOop k = klassOop(interfaces->obj_at(index));
+
+ // Note: can not use instanceKlass::cast here because
+ // interfaces' instanceKlass's C++ vtbls haven't been
+ // reinitialized yet (they will be once the interface classes
+ // are loaded)
+ symbolHandle name (THREAD, k->klass_part()->name());
+ resolve_super_or_fail(class_name, name, class_loader, Handle(), false, CHECK_(nh));
+ }
+
+ // Adjust methods to recover missing data. They need addresses for
+ // interpreter entry points and their default native method address
+ // must be reset.
+
+ // Updating methods must be done under a lock so multiple
+ // threads don't update these in parallel
+ // Shared classes are all currently loaded by the bootstrap
+ // classloader, so this will never cause a deadlock on
+ // a custom class loader lock.
+
+ {
+ Handle lockObject = compute_loader_lock_object(class_loader, THREAD);
+ check_loader_lock_contention(lockObject, THREAD);
+ ObjectLocker ol(lockObject, THREAD, true);
+
+ objArrayHandle methods (THREAD, ik->methods());
+ int num_methods = methods->length();
+ for (int index2 = 0; index2 < num_methods; ++index2) {
+ methodHandle m(THREAD, methodOop(methods->obj_at(index2)));
+ m()->link_method(m, CHECK_(nh));
+ }
+ }
+
+ if (TraceClassLoading) {
+ ResourceMark rm;
+ tty->print("[Loaded %s", ik->external_name());
+ tty->print(" from shared objects file");
+ tty->print_cr("]");
+ }
+ // notify a class loaded from shared object
+ ClassLoadingService::notify_class_loaded(instanceKlass::cast(ik()),
+ true /* shared class */);
+ }
+ return ik;
+}
+
+#ifdef KERNEL
+// Some classes on the bootstrap class path haven't been installed on the
+// system yet. Call the DownloadManager method to make them appear in the
+// bootstrap class path and try again to load the named class.
+// Note that with delegation class loaders all classes in another loader will
+// first try to call this so it'd better be fast!!
+static instanceKlassHandle download_and_retry_class_load(
+ symbolHandle class_name,
+ TRAPS) {
+
+ klassOop dlm = SystemDictionary::sun_jkernel_DownloadManager_klass();
+ instanceKlassHandle nk;
+
+ // If download manager class isn't loaded just return.
+ if (dlm == NULL) return nk;
+
+ { HandleMark hm(THREAD);
+ ResourceMark rm(THREAD);
+ Handle s = java_lang_String::create_from_symbol(class_name, CHECK_(nk));
+ Handle class_string = java_lang_String::externalize_classname(s, CHECK_(nk));
+
+ // return value
+ JavaValue result(T_OBJECT);
+
+ // Call the DownloadManager. We assume that it has a lock because
+ // multiple classes could be not found and downloaded at the same time.
+ // class sun.misc.DownloadManager;
+ // public static String getBootClassPathEntryForClass(String className);
+ JavaCalls::call_static(&result,
+ KlassHandle(THREAD, dlm),
+ vmSymbolHandles::getBootClassPathEntryForClass_name(),
+ vmSymbolHandles::string_string_signature(),
+ class_string,
+ CHECK_(nk));
+
+ // Get result.string and add to bootclasspath
+ assert(result.get_type() == T_OBJECT, "just checking");
+ oop obj = (oop) result.get_jobject();
+ if (obj == NULL) { return nk; }
+
+ char* new_class_name = java_lang_String::as_utf8_string(obj);
+
+ // lock the loader
+ // we use this lock because JVMTI does.
+ Handle loader_lock(THREAD, SystemDictionary::system_loader_lock());
+
+ ObjectLocker ol(loader_lock, THREAD);
+ // add the file to the bootclasspath
+ ClassLoader::update_class_path_entry_list(new_class_name, true);
+ } // end HandleMark
+
+ if (TraceClassLoading) {
+ ClassLoader::print_bootclasspath();
+ }
+ return ClassLoader::load_classfile(class_name, CHECK_(nk));
+}
+#endif // KERNEL
+
+
+instanceKlassHandle SystemDictionary::load_instance_class(symbolHandle class_name, Handle class_loader, TRAPS) {
+ instanceKlassHandle nh = instanceKlassHandle(); // null Handle
+ if (class_loader.is_null()) {
+ // Search the shared system dictionary for classes preloaded into the
+ // shared spaces.
+ instanceKlassHandle k;
+ k = load_shared_class(class_name, class_loader, THREAD);
+
+ if (k.is_null()) {
+ // Use VM class loader
+ k = ClassLoader::load_classfile(class_name, CHECK_(nh));
+ }
+
+#ifdef KERNEL
+ // If the VM class loader has failed to load the class, call the
+ // DownloadManager class to make it magically appear on the classpath
+ // and try again. This is only configured with the Kernel VM.
+ if (k.is_null()) {
+ k = download_and_retry_class_load(class_name, CHECK_(nh));
+ }
+#endif // KERNEL
+
+ // find_or_define_instance_class may return a different k
+ if (!k.is_null()) {
+ k = find_or_define_instance_class(class_name, class_loader, k, CHECK_(nh));
+ }
+ return k;
+ } else {
+ // Use user specified class loader to load class. Call loadClass operation on class_loader.
+ ResourceMark rm(THREAD);
+
+ Handle s = java_lang_String::create_from_symbol(class_name, CHECK_(nh));
+ // Translate to external class name format, i.e., convert '/' chars to '.'
+ Handle string = java_lang_String::externalize_classname(s, CHECK_(nh));
+
+ JavaValue result(T_OBJECT);
+
+ KlassHandle spec_klass (THREAD, SystemDictionary::classloader_klass());
+
+ // UnsyncloadClass option means don't synchronize loadClass() calls.
+ // loadClassInternal() is synchronized and public loadClass(String) is not.
+ // This flag is for diagnostic purposes only. It is risky to call
+ // custom class loaders without synchronization.
+ // WARNING If a custom class loader does NOT synchronizer findClass, or callers of
+ // findClass, this flag risks unexpected timing bugs in the field.
+ // Do NOT assume this will be supported in future releases.
+ if (!UnsyncloadClass && has_loadClassInternal()) {
+ JavaCalls::call_special(&result,
+ class_loader,
+ spec_klass,
+ vmSymbolHandles::loadClassInternal_name(),
+ vmSymbolHandles::string_class_signature(),
+ string,
+ CHECK_(nh));
+ } else {
+ JavaCalls::call_virtual(&result,
+ class_loader,
+ spec_klass,
+ vmSymbolHandles::loadClass_name(),
+ vmSymbolHandles::string_class_signature(),
+ string,
+ CHECK_(nh));
+ }
+
+ assert(result.get_type() == T_OBJECT, "just checking");
+ oop obj = (oop) result.get_jobject();
+
+ // Primitive classes return null since forName() can not be
+ // used to obtain any of the Class objects representing primitives or void
+ if ((obj != NULL) && !(java_lang_Class::is_primitive(obj))) {
+ instanceKlassHandle k =
+ instanceKlassHandle(THREAD, java_lang_Class::as_klassOop(obj));
+ // For user defined Java class loaders, check that the name returned is
+ // the same as that requested. This check is done for the bootstrap
+ // loader when parsing the class file.
+ if (class_name() == k->name()) {
+ return k;
+ }
+ }
+ // Class is not found or has the wrong name, return NULL
+ return nh;
+ }
+}
+
+void SystemDictionary::define_instance_class(instanceKlassHandle k, TRAPS) {
+
+ Handle class_loader_h(THREAD, k->class_loader());
+
+ // for bootstrap classloader don't acquire lock
+ if (!class_loader_h.is_null()) {
+ assert(ObjectSynchronizer::current_thread_holds_lock((JavaThread*)THREAD,
+ compute_loader_lock_object(class_loader_h, THREAD)),
+ "define called without lock");
+ }
+
+
+ // Check class-loading constraints. Throw exception if violation is detected.
+ // Grabs and releases SystemDictionary_lock
+ // The check_constraints/find_class call and update_dictionary sequence
+ // must be "atomic" for a specific class/classloader pair so we never
+ // define two different instanceKlasses for that class/classloader pair.
+ // Existing classloaders will call define_instance_class with the
+ // classloader lock held
+ // Parallel classloaders will call find_or_define_instance_class
+ // which will require a token to perform the define class
+ symbolHandle name_h(THREAD, k->name());
+ unsigned int d_hash = dictionary()->compute_hash(name_h, class_loader_h);
+ int d_index = dictionary()->hash_to_index(d_hash);
+ check_constraints(d_index, d_hash, k, class_loader_h, true, CHECK);
+
+ // Register class just loaded with class loader (placed in Vector)
+ // Note we do this before updating the dictionary, as this can
+ // fail with an OutOfMemoryError (if it does, we will *not* put this
+ // class in the dictionary and will not update the class hierarchy).
+ if (k->class_loader() != NULL) {
+ methodHandle m(THREAD, Universe::loader_addClass_method());
+ JavaValue result(T_VOID);
+ JavaCallArguments args(class_loader_h);
+ args.push_oop(Handle(THREAD, k->java_mirror()));
+ JavaCalls::call(&result, m, &args, CHECK);
+ }
+
+ // Add the new class. We need recompile lock during update of CHA.
+ {
+ unsigned int p_hash = placeholders()->compute_hash(name_h, class_loader_h);
+ int p_index = placeholders()->hash_to_index(p_hash);
+
+ MutexLocker mu_r(Compile_lock, THREAD);
+
+ // Add to class hierarchy, initialize vtables, and do possible
+ // deoptimizations.
+ add_to_hierarchy(k, CHECK); // No exception, but can block
+
+ // Add to systemDictionary - so other classes can see it.
+ // Grabs and releases SystemDictionary_lock
+ update_dictionary(d_index, d_hash, p_index, p_hash,
+ k, class_loader_h, THREAD);
+ }
+ k->eager_initialize(THREAD);
+
+ // notify jvmti
+ if (JvmtiExport::should_post_class_load()) {
+ assert(THREAD->is_Java_thread(), "thread->is_Java_thread()");
+ JvmtiExport::post_class_load((JavaThread *) THREAD, k());
+
+ }
+}
+
+// Support parallel classloading
+// Initial implementation for bootstrap classloader
+// For future:
+// For custom class loaders that support parallel classloading,
+// in case they do not synchronize around
+// FindLoadedClass/DefineClass calls, we check for parallel
+// loading for them, wait if a defineClass is in progress
+// and return the initial requestor's results
+// For better performance, the class loaders should synchronize
+// findClass(), i.e. FindLoadedClass/DefineClass or they
+// potentially waste time reading and parsing the bytestream.
+// Note: VM callers should ensure consistency of k/class_name,class_loader
+instanceKlassHandle SystemDictionary::find_or_define_instance_class(symbolHandle class_name, Handle class_loader, instanceKlassHandle k, TRAPS) {
+
+ instanceKlassHandle nh = instanceKlassHandle(); // null Handle
+
+ unsigned int d_hash = dictionary()->compute_hash(class_name, class_loader);
+ int d_index = dictionary()->hash_to_index(d_hash);
+
+// Hold SD lock around find_class and placeholder creation for DEFINE_CLASS
+ unsigned int p_hash = placeholders()->compute_hash(class_name, class_loader);
+ int p_index = placeholders()->hash_to_index(p_hash);
+ PlaceholderEntry* probe;
+
+ {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ // First check if class already defined
+ klassOop check = find_class(d_index, d_hash, class_name, class_loader);
+ if (check != NULL) {
+ return(instanceKlassHandle(THREAD, check));
+ }
+
+ // Acquire define token for this class/classloader
+ symbolHandle nullsymbolHandle;
+ probe = placeholders()->find_and_add(p_index, p_hash, class_name, class_loader, PlaceholderTable::DEFINE_CLASS, nullsymbolHandle, THREAD);
+ // Check if another thread defining in parallel
+ if (probe->definer() == NULL) {
+ // Thread will define the class
+ probe->set_definer(THREAD);
+ } else {
+ // Wait for defining thread to finish and return results
+ while (probe->definer() != NULL) {
+ SystemDictionary_lock->wait();
+ }
+ if (probe->instanceKlass() != NULL) {
+ probe->remove_seen_thread(THREAD, PlaceholderTable::DEFINE_CLASS);
+ return(instanceKlassHandle(THREAD, probe->instanceKlass()));
+ } else {
+ // If definer had an error, try again as any new thread would
+ probe->set_definer(THREAD);
+#ifdef ASSERT
+ klassOop check = find_class(d_index, d_hash, class_name, class_loader);
+ assert(check == NULL, "definer missed recording success");
+#endif
+ }
+ }
+ }
+
+ define_instance_class(k, THREAD);
+
+ Handle linkage_exception = Handle(); // null handle
+
+ // definer must notify any waiting threads
+ {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ PlaceholderEntry* probe = placeholders()->get_entry(p_index, p_hash, class_name, class_loader);
+ assert(probe != NULL, "DEFINE_CLASS placeholder lost?");
+ if (probe != NULL) {
+ if (HAS_PENDING_EXCEPTION) {
+ linkage_exception = Handle(THREAD,PENDING_EXCEPTION);
+ CLEAR_PENDING_EXCEPTION;
+ } else {
+ probe->set_instanceKlass(k());
+ }
+ probe->set_definer(NULL);
+ probe->remove_seen_thread(THREAD, PlaceholderTable::DEFINE_CLASS);
+ SystemDictionary_lock->notify_all();
+ }
+ }
+
+ // Can't throw exception while holding lock due to rank ordering
+ if (linkage_exception() != NULL) {
+ THROW_OOP_(linkage_exception(), nh); // throws exception and returns
+ }
+
+ return k;
+}
+
+Handle SystemDictionary::compute_loader_lock_object(Handle class_loader, TRAPS) {
+ // If class_loader is NULL we synchronize on _system_loader_lock_obj
+ if (class_loader.is_null()) {
+ return Handle(THREAD, _system_loader_lock_obj);
+ } else {
+ return class_loader;
+ }
+}
+
+// This method is added to check how often we have to wait to grab loader
+// lock. The results are being recorded in the performance counters defined in
+// ClassLoader::_sync_systemLoaderLockContentionRate and
+// ClassLoader::_sync_nonSystemLoaderLockConteionRate.
+void SystemDictionary::check_loader_lock_contention(Handle loader_lock, TRAPS) {
+ if (!UsePerfData) {
+ return;
+ }
+
+ assert(!loader_lock.is_null(), "NULL lock object");
+
+ if (ObjectSynchronizer::query_lock_ownership((JavaThread*)THREAD, loader_lock)
+ == ObjectSynchronizer::owner_other) {
+ // contention will likely happen, so increment the corresponding
+ // contention counter.
+ if (loader_lock() == _system_loader_lock_obj) {
+ ClassLoader::sync_systemLoaderLockContentionRate()->inc();
+ } else {
+ ClassLoader::sync_nonSystemLoaderLockContentionRate()->inc();
+ }
+ }
+}
+
+// ----------------------------------------------------------------------------
+// Lookup
+
+klassOop SystemDictionary::find_class(int index, unsigned int hash,
+ symbolHandle class_name,
+ Handle class_loader) {
+ assert_locked_or_safepoint(SystemDictionary_lock);
+ assert (index == dictionary()->index_for(class_name, class_loader),
+ "incorrect index?");
+
+ klassOop k = dictionary()->find_class(index, hash, class_name, class_loader);
+ return k;
+}
+
+
+// Basic find on classes in the midst of being loaded
+symbolOop SystemDictionary::find_placeholder(int index, unsigned int hash,
+ symbolHandle class_name,
+ Handle class_loader) {
+ assert_locked_or_safepoint(SystemDictionary_lock);
+
+ return placeholders()->find_entry(index, hash, class_name, class_loader);
+}
+
+
+// Used for assertions and verification only
+oop SystemDictionary::find_class_or_placeholder(symbolHandle class_name,
+ Handle class_loader) {
+ #ifndef ASSERT
+ guarantee(VerifyBeforeGC ||
+ VerifyDuringGC ||
+ VerifyBeforeExit ||
+ VerifyAfterGC, "too expensive");
+ #endif
+ assert_locked_or_safepoint(SystemDictionary_lock);
+ symbolOop class_name_ = class_name();
+ oop class_loader_ = class_loader();
+
+ // First look in the loaded class array
+ unsigned int d_hash = dictionary()->compute_hash(class_name, class_loader);
+ int d_index = dictionary()->hash_to_index(d_hash);
+ oop lookup = find_class(d_index, d_hash, class_name, class_loader);
+
+ if (lookup == NULL) {
+ // Next try the placeholders
+ unsigned int p_hash = placeholders()->compute_hash(class_name,class_loader);
+ int p_index = placeholders()->hash_to_index(p_hash);
+ lookup = find_placeholder(p_index, p_hash, class_name, class_loader);
+ }
+
+ return lookup;
+}
+
+
+// Get the next class in the diictionary.
+klassOop SystemDictionary::try_get_next_class() {
+ return dictionary()->try_get_next_class();
+}
+
+
+// ----------------------------------------------------------------------------
+// Update hierachy. This is done before the new klass has been added to the SystemDictionary. The Recompile_lock
+// is held, to ensure that the compiler is not using the class hierachy, and that deoptimization will kick in
+// before a new class is used.
+
+void SystemDictionary::add_to_hierarchy(instanceKlassHandle k, TRAPS) {
+ assert(k.not_null(), "just checking");
+ // Link into hierachy. Make sure the vtables are initialized before linking into
+ k->append_to_sibling_list(); // add to superklass/sibling list
+ k->process_interfaces(THREAD); // handle all "implements" declarations
+ k->set_init_state(instanceKlass::loaded);
+ // Now flush all code that depended on old class hierarchy.
+ // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
+ // Also, first reinitialize vtable because it may have gotten out of synch
+ // while the new class wasn't connected to the class hierarchy.
+ Universe::flush_dependents_on(k);
+}
+
+
+// ----------------------------------------------------------------------------
+// GC support
+
+// Following roots during mark-sweep is separated in two phases.
+//
+// The first phase follows preloaded classes and all other system
+// classes, since these will never get unloaded anyway.
+//
+// The second phase removes (unloads) unreachable classes from the
+// system dictionary and follows the remaining classes' contents.
+
+void SystemDictionary::always_strong_oops_do(OopClosure* blk) {
+ // Follow preloaded classes/mirrors and system loader object
+ blk->do_oop(&_java_system_loader);
+ preloaded_oops_do(blk);
+ always_strong_classes_do(blk);
+}
+
+
+void SystemDictionary::always_strong_classes_do(OopClosure* blk) {
+ // Follow all system classes and temporary placeholders in dictionary
+ dictionary()->always_strong_classes_do(blk);
+
+ // Placeholders. These are *always* strong roots, as they
+ // represent classes we're actively loading.
+ placeholders_do(blk);
+
+ // Loader constraints. We must keep the symbolOop used in the name alive.
+ constraints()->always_strong_classes_do(blk);
+
+ // Resolution errors keep the symbolOop for the error alive
+ resolution_errors()->always_strong_classes_do(blk);
+}
+
+
+void SystemDictionary::placeholders_do(OopClosure* blk) {
+ placeholders()->oops_do(blk);
+}
+
+
+bool SystemDictionary::do_unloading(BoolObjectClosure* is_alive) {
+ bool result = dictionary()->do_unloading(is_alive);
+ constraints()->purge_loader_constraints(is_alive);
+ resolution_errors()->purge_resolution_errors(is_alive);
+ return result;
+}
+
+
+// The mirrors are scanned by shared_oops_do() which is
+// not called by oops_do(). In order to process oops in
+// a necessary order, shared_oops_do() is call by
+// Universe::oops_do().
+void SystemDictionary::oops_do(OopClosure* f) {
+ // Adjust preloaded classes and system loader object
+ f->do_oop(&_java_system_loader);
+ preloaded_oops_do(f);
+
+ lazily_loaded_oops_do(f);
+
+ // Adjust dictionary
+ dictionary()->oops_do(f);
+
+ // Partially loaded classes
+ placeholders()->oops_do(f);
+
+ // Adjust constraint table
+ constraints()->oops_do(f);
+
+ // Adjust resolution error table
+ resolution_errors()->oops_do(f);
+}
+
+
+void SystemDictionary::preloaded_oops_do(OopClosure* f) {
+ f->do_oop((oop*) &_string_klass);
+ f->do_oop((oop*) &_object_klass);
+ f->do_oop((oop*) &_class_klass);
+ f->do_oop((oop*) &_cloneable_klass);
+ f->do_oop((oop*) &_classloader_klass);
+ f->do_oop((oop*) &_serializable_klass);
+ f->do_oop((oop*) &_system_klass);
+
+ f->do_oop((oop*) &_throwable_klass);
+ f->do_oop((oop*) &_error_klass);
+ f->do_oop((oop*) &_threaddeath_klass);
+ f->do_oop((oop*) &_exception_klass);
+ f->do_oop((oop*) &_runtime_exception_klass);
+ f->do_oop((oop*) &_classNotFoundException_klass);
+ f->do_oop((oop*) &_noClassDefFoundError_klass);
+ f->do_oop((oop*) &_linkageError_klass);
+ f->do_oop((oop*) &_classCastException_klass);
+ f->do_oop((oop*) &_arrayStoreException_klass);
+ f->do_oop((oop*) &_virtualMachineError_klass);
+ f->do_oop((oop*) &_outOfMemoryError_klass);
+ f->do_oop((oop*) &_StackOverflowError_klass);
+ f->do_oop((oop*) &_illegalMonitorStateException_klass);
+ f->do_oop((oop*) &_protectionDomain_klass);
+ f->do_oop((oop*) &_AccessControlContext_klass);
+
+ f->do_oop((oop*) &_reference_klass);
+ f->do_oop((oop*) &_soft_reference_klass);
+ f->do_oop((oop*) &_weak_reference_klass);
+ f->do_oop((oop*) &_final_reference_klass);
+ f->do_oop((oop*) &_phantom_reference_klass);
+ f->do_oop((oop*) &_finalizer_klass);
+
+ f->do_oop((oop*) &_thread_klass);
+ f->do_oop((oop*) &_threadGroup_klass);
+ f->do_oop((oop*) &_properties_klass);
+ f->do_oop((oop*) &_reflect_accessible_object_klass);
+ f->do_oop((oop*) &_reflect_field_klass);
+ f->do_oop((oop*) &_reflect_method_klass);
+ f->do_oop((oop*) &_reflect_constructor_klass);
+ f->do_oop((oop*) &_reflect_magic_klass);
+ f->do_oop((oop*) &_reflect_method_accessor_klass);
+ f->do_oop((oop*) &_reflect_constructor_accessor_klass);
+ f->do_oop((oop*) &_reflect_delegating_classloader_klass);
+ f->do_oop((oop*) &_reflect_constant_pool_klass);
+ f->do_oop((oop*) &_reflect_unsafe_static_field_accessor_impl_klass);
+
+ f->do_oop((oop*) &_stringBuffer_klass);
+ f->do_oop((oop*) &_vector_klass);
+ f->do_oop((oop*) &_hashtable_klass);
+
+ f->do_oop((oop*) &_stackTraceElement_klass);
+
+ f->do_oop((oop*) &_java_nio_Buffer_klass);
+
+ f->do_oop((oop*) &_sun_misc_AtomicLongCSImpl_klass);
+ f->do_oop((oop*) &_sun_jkernel_DownloadManager_klass);
+
+ f->do_oop((oop*) &_boolean_klass);
+ f->do_oop((oop*) &_char_klass);
+ f->do_oop((oop*) &_float_klass);
+ f->do_oop((oop*) &_double_klass);
+ f->do_oop((oop*) &_byte_klass);
+ f->do_oop((oop*) &_short_klass);
+ f->do_oop((oop*) &_int_klass);
+ f->do_oop((oop*) &_long_klass);
+ {
+ for (int i = 0; i < T_VOID+1; i++) {
+ if (_box_klasses[i] != NULL) {
+ assert(i >= T_BOOLEAN, "checking");
+ f->do_oop((oop*) &_box_klasses[i]);
+ }
+ }
+ }
+
+ // The basic type mirrors would have already been processed in
+ // Universe::oops_do(), via a call to shared_oops_do(), so should
+ // not be processed again.
+
+ f->do_oop((oop*) &_system_loader_lock_obj);
+ FilteredFieldsMap::klasses_oops_do(f);
+}
+
+void SystemDictionary::lazily_loaded_oops_do(OopClosure* f) {
+ f->do_oop((oop*) &_abstract_ownable_synchronizer_klass);
+}
+
+// Just the classes from defining class loaders
+// Don't iterate over placeholders
+void SystemDictionary::classes_do(void f(klassOop)) {
+ dictionary()->classes_do(f);
+}
+
+// Added for initialize_itable_for_klass
+// Just the classes from defining class loaders
+// Don't iterate over placeholders
+void SystemDictionary::classes_do(void f(klassOop, TRAPS), TRAPS) {
+ dictionary()->classes_do(f, CHECK);
+}
+
+// All classes, and their class loaders
+// Don't iterate over placeholders
+void SystemDictionary::classes_do(void f(klassOop, oop)) {
+ dictionary()->classes_do(f);
+}
+
+// All classes, and their class loaders
+// (added for helpers that use HandleMarks and ResourceMarks)
+// Don't iterate over placeholders
+void SystemDictionary::classes_do(void f(klassOop, oop, TRAPS), TRAPS) {
+ dictionary()->classes_do(f, CHECK);
+}
+
+void SystemDictionary::placeholders_do(void f(symbolOop, oop)) {
+ placeholders()->entries_do(f);
+}
+
+void SystemDictionary::methods_do(void f(methodOop)) {
+ dictionary()->methods_do(f);
+}
+
+// ----------------------------------------------------------------------------
+// Lazily load klasses
+
+void SystemDictionary::load_abstract_ownable_synchronizer_klass(TRAPS) {
+ assert(JDK_Version::is_gte_jdk16x_version(), "Must be JDK 1.6 or later");
+
+ // if multiple threads calling this function, only one thread will load
+ // the class. The other threads will find the loaded version once the
+ // class is loaded.
+ klassOop aos = _abstract_ownable_synchronizer_klass;
+ if (aos == NULL) {
+ klassOop k = resolve_or_fail(vmSymbolHandles::java_util_concurrent_locks_AbstractOwnableSynchronizer(), true, CHECK);
+ // Force a fence to prevent any read before the write completes
+ OrderAccess::fence();
+ _abstract_ownable_synchronizer_klass = k;
+ }
+}
+
+// ----------------------------------------------------------------------------
+// Initialization
+
+void SystemDictionary::initialize(TRAPS) {
+ // Allocate arrays
+ assert(dictionary() == NULL,
+ "SystemDictionary should only be initialized once");
+ _dictionary = new Dictionary(_nof_buckets);
+ _placeholders = new PlaceholderTable(_nof_buckets);
+ _number_of_modifications = 0;
+ _loader_constraints = new LoaderConstraintTable(_loader_constraint_size);
+ _resolution_errors = new ResolutionErrorTable(_resolution_error_size);
+
+ // Allocate private object used as system class loader lock
+ _system_loader_lock_obj = oopFactory::new_system_objArray(0, CHECK);
+ // Initialize basic classes
+ initialize_preloaded_classes(CHECK);
+}
+
+
+void SystemDictionary::initialize_preloaded_classes(TRAPS) {
+ assert(_object_klass == NULL, "preloaded classes should only be initialized once");
+ // Preload commonly used klasses
+ _object_klass = resolve_or_fail(vmSymbolHandles::java_lang_Object(), true, CHECK);
+ _string_klass = resolve_or_fail(vmSymbolHandles::java_lang_String(), true, CHECK);
+ _class_klass = resolve_or_fail(vmSymbolHandles::java_lang_Class(), true, CHECK);
+ debug_only(instanceKlass::verify_class_klass_nonstatic_oop_maps(_class_klass));
+ // Fixup mirrors for classes loaded before java.lang.Class.
+ // These calls iterate over the objects currently in the perm gen
+ // so calling them at this point is matters (not before when there
+ // are fewer objects and not later after there are more objects
+ // in the perm gen.
+ Universe::initialize_basic_type_mirrors(CHECK);
+ Universe::fixup_mirrors(CHECK);
+
+ _cloneable_klass = resolve_or_fail(vmSymbolHandles::java_lang_Cloneable(), true, CHECK);
+ _classloader_klass = resolve_or_fail(vmSymbolHandles::java_lang_ClassLoader(), true, CHECK);
+ _serializable_klass = resolve_or_fail(vmSymbolHandles::java_io_Serializable(), true, CHECK);
+ _system_klass = resolve_or_fail(vmSymbolHandles::java_lang_System(), true, CHECK);
+
+ _throwable_klass = resolve_or_fail(vmSymbolHandles::java_lang_Throwable(), true, CHECK);
+ _error_klass = resolve_or_fail(vmSymbolHandles::java_lang_Error(), true, CHECK);
+ _threaddeath_klass = resolve_or_fail(vmSymbolHandles::java_lang_ThreadDeath(), true, CHECK);
+ _exception_klass = resolve_or_fail(vmSymbolHandles::java_lang_Exception(), true, CHECK);
+ _runtime_exception_klass = resolve_or_fail(vmSymbolHandles::java_lang_RuntimeException(), true, CHECK);
+ _protectionDomain_klass = resolve_or_fail(vmSymbolHandles::java_security_ProtectionDomain(), true, CHECK);
+ _AccessControlContext_klass = resolve_or_fail(vmSymbolHandles::java_security_AccessControlContext(), true, CHECK);
+ _classNotFoundException_klass = resolve_or_fail(vmSymbolHandles::java_lang_ClassNotFoundException(), true, CHECK);
+ _noClassDefFoundError_klass = resolve_or_fail(vmSymbolHandles::java_lang_NoClassDefFoundError(), true, CHECK);
+ _linkageError_klass = resolve_or_fail(vmSymbolHandles::java_lang_LinkageError(), true, CHECK);
+ _classCastException_klass = resolve_or_fail(vmSymbolHandles::java_lang_ClassCastException(), true, CHECK);
+ _arrayStoreException_klass = resolve_or_fail(vmSymbolHandles::java_lang_ArrayStoreException(), true, CHECK);
+ _virtualMachineError_klass = resolve_or_fail(vmSymbolHandles::java_lang_VirtualMachineError(), true, CHECK);
+ _outOfMemoryError_klass = resolve_or_fail(vmSymbolHandles::java_lang_OutOfMemoryError(), true, CHECK);
+ _StackOverflowError_klass = resolve_or_fail(vmSymbolHandles::java_lang_StackOverflowError(), true, CHECK);
+ _illegalMonitorStateException_klass = resolve_or_fail(vmSymbolHandles::java_lang_IllegalMonitorStateException(), true, CHECK);
+
+ // Preload ref klasses and set reference types
+ _reference_klass = resolve_or_fail(vmSymbolHandles::java_lang_ref_Reference(), true, CHECK);
+ instanceKlass::cast(_reference_klass)->set_reference_type(REF_OTHER);
+ instanceRefKlass::update_nonstatic_oop_maps(_reference_klass);
+
+ _soft_reference_klass = resolve_or_fail(vmSymbolHandles::java_lang_ref_SoftReference(), true, CHECK);
+ instanceKlass::cast(_soft_reference_klass)->set_reference_type(REF_SOFT);
+ _weak_reference_klass = resolve_or_fail(vmSymbolHandles::java_lang_ref_WeakReference(), true, CHECK);
+ instanceKlass::cast(_weak_reference_klass)->set_reference_type(REF_WEAK);
+ _final_reference_klass = resolve_or_fail(vmSymbolHandles::java_lang_ref_FinalReference(), true, CHECK);
+ instanceKlass::cast(_final_reference_klass)->set_reference_type(REF_FINAL);
+ _phantom_reference_klass = resolve_or_fail(vmSymbolHandles::java_lang_ref_PhantomReference(), true, CHECK);
+ instanceKlass::cast(_phantom_reference_klass)->set_reference_type(REF_PHANTOM);
+ _finalizer_klass = resolve_or_fail(vmSymbolHandles::java_lang_ref_Finalizer(), true, CHECK);
+
+ _thread_klass = resolve_or_fail(vmSymbolHandles::java_lang_Thread(), true, CHECK);
+ _threadGroup_klass = resolve_or_fail(vmSymbolHandles::java_lang_ThreadGroup(), true, CHECK);
+ _properties_klass = resolve_or_fail(vmSymbolHandles::java_util_Properties(), true, CHECK);
+ _reflect_accessible_object_klass = resolve_or_fail(vmSymbolHandles::java_lang_reflect_AccessibleObject(), true, CHECK);
+ _reflect_field_klass = resolve_or_fail(vmSymbolHandles::java_lang_reflect_Field(), true, CHECK);
+ _reflect_method_klass = resolve_or_fail(vmSymbolHandles::java_lang_reflect_Method(), true, CHECK);
+ _reflect_constructor_klass = resolve_or_fail(vmSymbolHandles::java_lang_reflect_Constructor(), true, CHECK);
+ // Universe::is_gte_jdk14x_version() is not set up by this point.
+ // It's okay if these turn out to be NULL in non-1.4 JDKs.
+ _reflect_magic_klass = resolve_or_null(vmSymbolHandles::sun_reflect_MagicAccessorImpl(), CHECK);
+ _reflect_method_accessor_klass = resolve_or_null(vmSymbolHandles::sun_reflect_MethodAccessorImpl(), CHECK);
+ _reflect_constructor_accessor_klass = resolve_or_null(vmSymbolHandles::sun_reflect_ConstructorAccessorImpl(), CHECK);
+ _reflect_delegating_classloader_klass = resolve_or_null(vmSymbolHandles::sun_reflect_DelegatingClassLoader(), CHECK);
+ _reflect_constant_pool_klass = resolve_or_null(vmSymbolHandles::sun_reflect_ConstantPool(), CHECK);
+ _reflect_unsafe_static_field_accessor_impl_klass = resolve_or_null(vmSymbolHandles::sun_reflect_UnsafeStaticFieldAccessorImpl(), CHECK);
+
+ _vector_klass = resolve_or_fail(vmSymbolHandles::java_util_Vector(), true, CHECK);
+ _hashtable_klass = resolve_or_fail(vmSymbolHandles::java_util_Hashtable(), true, CHECK);
+ _stringBuffer_klass = resolve_or_fail(vmSymbolHandles::java_lang_StringBuffer(), true, CHECK);
+
+ // It's NULL in non-1.4 JDKs.
+ _stackTraceElement_klass = resolve_or_null(vmSymbolHandles::java_lang_StackTraceElement(), CHECK);
+
+ // 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.
+ _java_nio_Buffer_klass = resolve_or_null(vmSymbolHandles::java_nio_Buffer(), CHECK);
+
+ // If this class isn't present, it won't be referenced.
+ _sun_misc_AtomicLongCSImpl_klass = resolve_or_null(vmSymbolHandles::sun_misc_AtomicLongCSImpl(), CHECK);
+#ifdef KERNEL
+ _sun_jkernel_DownloadManager_klass = resolve_or_null(vmSymbolHandles::sun_jkernel_DownloadManager(), CHECK);
+ if (_sun_jkernel_DownloadManager_klass == NULL) {
+ warning("Cannot find sun/jkernel/DownloadManager");
+ }
+#endif // KERNEL
+
+ // Preload boxing klasses
+ _boolean_klass = resolve_or_fail(vmSymbolHandles::java_lang_Boolean(), true, CHECK);
+ _char_klass = resolve_or_fail(vmSymbolHandles::java_lang_Character(), true, CHECK);
+ _float_klass = resolve_or_fail(vmSymbolHandles::java_lang_Float(), true, CHECK);
+ _double_klass = resolve_or_fail(vmSymbolHandles::java_lang_Double(), true, CHECK);
+ _byte_klass = resolve_or_fail(vmSymbolHandles::java_lang_Byte(), true, CHECK);
+ _short_klass = resolve_or_fail(vmSymbolHandles::java_lang_Short(), true, CHECK);
+ _int_klass = resolve_or_fail(vmSymbolHandles::java_lang_Integer(), true, CHECK);
+ _long_klass = resolve_or_fail(vmSymbolHandles::java_lang_Long(), true, CHECK);
+
+ _box_klasses[T_BOOLEAN] = _boolean_klass;
+ _box_klasses[T_CHAR] = _char_klass;
+ _box_klasses[T_FLOAT] = _float_klass;
+ _box_klasses[T_DOUBLE] = _double_klass;
+ _box_klasses[T_BYTE] = _byte_klass;
+ _box_klasses[T_SHORT] = _short_klass;
+ _box_klasses[T_INT] = _int_klass;
+ _box_klasses[T_LONG] = _long_klass;
+ //_box_klasses[T_OBJECT] = _object_klass;
+ //_box_klasses[T_ARRAY] = _object_klass;
+
+ { // Compute whether we should use loadClass or loadClassInternal when loading classes.
+ methodOop method = instanceKlass::cast(classloader_klass())->find_method(vmSymbols::loadClassInternal_name(), vmSymbols::string_class_signature());
+ _has_loadClassInternal = (method != NULL);
+ }
+
+ { // Compute whether we should use checkPackageAccess or NOT
+ methodOop method = instanceKlass::cast(classloader_klass())->find_method(vmSymbols::checkPackageAccess_name(), vmSymbols::class_protectiondomain_signature());
+ _has_checkPackageAccess = (method != NULL);
+ }
+}
+
+// Tells if a given klass is a box (wrapper class, such as java.lang.Integer).
+// If so, returns the basic type it holds. If not, returns T_OBJECT.
+BasicType SystemDictionary::box_klass_type(klassOop k) {
+ assert(k != NULL, "");
+ for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
+ if (_box_klasses[i] == k)
+ return (BasicType)i;
+ }
+ return T_OBJECT;
+}
+
+// Constraints on class loaders. The details of the algorithm can be
+// found in the OOPSLA'98 paper "Dynamic Class Loading in the Java
+// Virtual Machine" by Sheng Liang and Gilad Bracha. The basic idea is
+// that the system dictionary needs to maintain a set of contraints that
+// must be satisfied by all classes in the dictionary.
+// if defining is true, then LinkageError if already in systemDictionary
+// if initiating loader, then ok if instanceKlass matches existing entry
+
+void SystemDictionary::check_constraints(int d_index, unsigned int d_hash,
+ instanceKlassHandle k,
+ Handle class_loader, bool defining,
+ TRAPS) {
+ const char *linkage_error = NULL;
+ {
+ symbolHandle name (THREAD, k->name());
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+
+ klassOop check = find_class(d_index, d_hash, name, class_loader);
+ if (check != (klassOop)NULL) {
+ // if different instanceKlass - duplicate class definition,
+ // else - ok, class loaded by a different thread in parallel,
+ // we should only have found it if it was done loading and ok to use
+ // system dictionary only holds instance classes, placeholders
+ // also holds array classes
+
+ assert(check->klass_part()->oop_is_instance(), "noninstance in systemdictionary");
+ if ((defining == true) || (k() != check)) {
+ linkage_error = "loader (instance of %s): attempted duplicate class "
+ "definition for name: \"%s\"";
+ } else {
+ return;
+ }
+ }
+
+#ifdef ASSERT
+ unsigned int p_hash = placeholders()->compute_hash(name, class_loader);
+ int p_index = placeholders()->hash_to_index(p_hash);
+ symbolOop ph_check = find_placeholder(p_index, p_hash, name, class_loader);
+ assert(ph_check == NULL || ph_check == name(), "invalid symbol");
+#endif
+
+ if (linkage_error == NULL) {
+ if (constraints()->check_or_update(k, class_loader, name) == false) {
+ linkage_error = "loader constraint violation: loader (instance of %s)"
+ " previously initiated loading for a different type with name \"%s\"";
+ }
+ }
+ }
+
+ // Throw error now if needed (cannot throw while holding
+ // SystemDictionary_lock because of rank ordering)
+
+ if (linkage_error) {
+ ResourceMark rm(THREAD);
+ const char* class_loader_name = loader_name(class_loader());
+ char* type_name = k->name()->as_C_string();
+ size_t buflen = strlen(linkage_error) + strlen(class_loader_name) +
+ strlen(type_name);
+ char* buf = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, buflen);
+ jio_snprintf(buf, buflen, linkage_error, class_loader_name, type_name);
+ THROW_MSG(vmSymbols::java_lang_LinkageError(), buf);
+ }
+}
+
+
+// Update system dictionary - done after check_constraint and add_to_hierachy
+// have been called.
+void SystemDictionary::update_dictionary(int d_index, unsigned int d_hash,
+ int p_index, unsigned int p_hash,
+ instanceKlassHandle k,
+ Handle class_loader,
+ TRAPS) {
+ // Compile_lock prevents systemDictionary updates during compilations
+ assert_locked_or_safepoint(Compile_lock);
+ symbolHandle name (THREAD, k->name());
+
+ {
+ MutexLocker mu1(SystemDictionary_lock, THREAD);
+
+ // See whether biased locking is enabled and if so set it for this
+ // klass.
+ // Note that this must be done past the last potential blocking
+ // point / safepoint. We enable biased locking lazily using a
+ // VM_Operation to iterate the SystemDictionary and installing the
+ // biasable mark word into each instanceKlass's prototype header.
+ // To avoid race conditions where we accidentally miss enabling the
+ // optimization for one class in the process of being added to the
+ // dictionary, we must not safepoint after the test of
+ // BiasedLocking::enabled().
+ if (UseBiasedLocking && BiasedLocking::enabled()) {
+ // Set biased locking bit for all loaded classes; it will be
+ // cleared if revocation occurs too often for this type
+ // NOTE that we must only do this when the class is initally
+ // defined, not each time it is referenced from a new class loader
+ if (k->class_loader() == class_loader()) {
+ k->set_prototype_header(markOopDesc::biased_locking_prototype());
+ }
+ }
+
+ // Check for a placeholder. If there, remove it and make a
+ // new system dictionary entry.
+ placeholders()->find_and_remove(p_index, p_hash, name, class_loader, THREAD);
+ klassOop sd_check = find_class(d_index, d_hash, name, class_loader);
+ if (sd_check == NULL) {
+ dictionary()->add_klass(name, class_loader, k);
+ notice_modification();
+ }
+#ifdef ASSERT
+ sd_check = find_class(d_index, d_hash, name, class_loader);
+ assert (sd_check != NULL, "should have entry in system dictionary");
+// Changed to allow PH to remain to complete class circularity checking
+// while only one thread can define a class at one time, multiple
+// classes can resolve the superclass for a class at one time,
+// and the placeholder is used to track that
+// symbolOop ph_check = find_placeholder(p_index, p_hash, name, class_loader);
+// assert (ph_check == NULL, "should not have a placeholder entry");
+#endif
+ SystemDictionary_lock->notify_all();
+ }
+}
+
+
+klassOop SystemDictionary::find_constrained_instance_or_array_klass(
+ symbolHandle class_name, Handle class_loader, TRAPS) {
+
+ // First see if it has been loaded directly.
+ // Force the protection domain to be null. (This removes protection checks.)
+ Handle no_protection_domain;
+ klassOop klass = find_instance_or_array_klass(class_name, class_loader,
+ no_protection_domain, CHECK_NULL);
+ if (klass != NULL)
+ return klass;
+
+ // Now look to see if it has been loaded elsewhere, and is subject to
+ // a loader constraint that would require this loader to return the
+ // klass that is already loaded.
+ if (FieldType::is_array(class_name())) {
+ // Array classes are hard because their klassOops are not kept in the
+ // constraint table. The array klass may be constrained, but the elem class
+ // may not be.
+ jint dimension;
+ symbolOop object_key;
+ BasicType t = FieldType::get_array_info(class_name(), &dimension,
+ &object_key, CHECK_(NULL));
+ if (t != T_OBJECT) {
+ klass = Universe::typeArrayKlassObj(t);
+ } else {
+ symbolHandle elem_name(THREAD, object_key);
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ klass = constraints()->find_constrained_elem_klass(class_name, elem_name, class_loader, THREAD);
+ }
+ if (klass != NULL) {
+ klass = Klass::cast(klass)->array_klass_or_null(dimension);
+ }
+ } else {
+ MutexLocker mu(SystemDictionary_lock, THREAD);
+ // Non-array classes are easy: simply check the constraint table.
+ klass = constraints()->find_constrained_klass(class_name, class_loader);
+ }
+
+ return klass;
+}
+
+
+bool SystemDictionary::add_loader_constraint(symbolHandle class_name,
+ Handle class_loader1,
+ Handle class_loader2,
+ Thread* THREAD) {
+ unsigned int d_hash1 = dictionary()->compute_hash(class_name, class_loader1);
+ int d_index1 = dictionary()->hash_to_index(d_hash1);
+
+ unsigned int d_hash2 = dictionary()->compute_hash(class_name, class_loader2);
+ int d_index2 = dictionary()->hash_to_index(d_hash2);
+
+ {
+ MutexLocker mu_s(SystemDictionary_lock, THREAD);
+
+ // Better never do a GC while we're holding these oops
+ No_Safepoint_Verifier nosafepoint;
+
+ klassOop klass1 = find_class(d_index1, d_hash1, class_name, class_loader1);
+ klassOop klass2 = find_class(d_index2, d_hash2, class_name, class_loader2);
+ return constraints()->add_entry(class_name, klass1, class_loader1,
+ klass2, class_loader2);
+ }
+}
+
+// Add entry to resolution error table to record the error when the first
+// attempt to resolve a reference to a class has failed.
+void SystemDictionary::add_resolution_error(constantPoolHandle pool, int which, symbolHandle error) {
+ unsigned int hash = resolution_errors()->compute_hash(pool, which);
+ int index = resolution_errors()->hash_to_index(hash);
+ {
+ MutexLocker ml(SystemDictionary_lock, Thread::current());
+ resolution_errors()->add_entry(index, hash, pool, which, error);
+ }
+}
+
+// Lookup resolution error table. Returns error if found, otherwise NULL.
+symbolOop SystemDictionary::find_resolution_error(constantPoolHandle pool, int which) {
+ unsigned int hash = resolution_errors()->compute_hash(pool, which);
+ int index = resolution_errors()->hash_to_index(hash);
+ {
+ MutexLocker ml(SystemDictionary_lock, Thread::current());
+ ResolutionErrorEntry* entry = resolution_errors()->find_entry(index, hash, pool, which);
+ return (entry != NULL) ? entry->error() : (symbolOop)NULL;
+ }
+}
+
+
+// Make sure all class components (including arrays) in the given
+// signature will be resolved to the same class in both loaders.
+// Returns the name of the type that failed a loader constraint check, or
+// NULL if no constraint failed. The returned C string needs cleaning up
+// with a ResourceMark in the caller
+char* SystemDictionary::check_signature_loaders(symbolHandle signature,
+ Handle loader1, Handle loader2,
+ bool is_method, TRAPS) {
+ // Nothing to do if loaders are the same.
+ if (loader1() == loader2()) {
+ return NULL;
+ }
+
+ SignatureStream sig_strm(signature, is_method);
+ while (!sig_strm.is_done()) {
+ if (sig_strm.is_object()) {
+ symbolOop s = sig_strm.as_symbol(CHECK_NULL);
+ symbolHandle sig (THREAD, s);
+ if (!add_loader_constraint(sig, loader1, loader2, THREAD)) {
+ return sig()->as_C_string();
+ }
+ }
+ sig_strm.next();
+ }
+ return NULL;
+}
+
+
+// Since the identity hash code for symbols changes when the symbols are
+// moved from the regular perm gen (hash in the mark word) to the shared
+// spaces (hash is the address), the classes loaded into the dictionary
+// may be in the wrong buckets.
+
+void SystemDictionary::reorder_dictionary() {
+ dictionary()->reorder_dictionary();
+}
+
+
+void SystemDictionary::copy_buckets(char** top, char* end) {
+ dictionary()->copy_buckets(top, end);
+}
+
+
+void SystemDictionary::copy_table(char** top, char* end) {
+ dictionary()->copy_table(top, end);
+}
+
+
+void SystemDictionary::reverse() {
+ dictionary()->reverse();
+}
+
+int SystemDictionary::number_of_classes() {
+ return dictionary()->number_of_entries();
+}
+
+
+// ----------------------------------------------------------------------------
+#ifndef PRODUCT
+
+void SystemDictionary::print() {
+ dictionary()->print();
+
+ // Placeholders
+ GCMutexLocker mu(SystemDictionary_lock);
+ placeholders()->print();
+
+ // loader constraints - print under SD_lock
+ constraints()->print();
+}
+
+#endif
+
+void SystemDictionary::verify() {
+ guarantee(dictionary() != NULL, "Verify of system dictionary failed");
+ guarantee(constraints() != NULL,
+ "Verify of loader constraints failed");
+ guarantee(dictionary()->number_of_entries() >= 0 &&
+ placeholders()->number_of_entries() >= 0,
+ "Verify of system dictionary failed");
+
+ // Verify dictionary
+ dictionary()->verify();
+
+ GCMutexLocker mu(SystemDictionary_lock);
+ placeholders()->verify();
+
+ // Verify constraint table
+ guarantee(constraints() != NULL, "Verify of loader constraints failed");
+ constraints()->verify(dictionary());
+}
+
+
+void SystemDictionary::verify_obj_klass_present(Handle obj,
+ symbolHandle class_name,
+ Handle class_loader) {
+ GCMutexLocker mu(SystemDictionary_lock);
+ oop probe = find_class_or_placeholder(class_name, class_loader);
+ if (probe == NULL) {
+ probe = SystemDictionary::find_shared_class(class_name);
+ }
+ guarantee(probe != NULL &&
+ (!probe->is_klass() || probe == obj()),
+ "Loaded klasses should be in SystemDictionary");
+}
+
+#ifndef PRODUCT
+
+// statistics code
+class ClassStatistics: AllStatic {
+ private:
+ static int nclasses; // number of classes
+ static int nmethods; // number of methods
+ static int nmethoddata; // number of methodData
+ static int class_size; // size of class objects in words
+ static int method_size; // size of method objects in words
+ static int debug_size; // size of debug info in methods
+ static int methoddata_size; // size of methodData objects in words
+
+ static void do_class(klassOop k) {
+ nclasses++;
+ class_size += k->size();
+ if (k->klass_part()->oop_is_instance()) {
+ instanceKlass* ik = (instanceKlass*)k->klass_part();
+ class_size += ik->methods()->size();
+ class_size += ik->constants()->size();
+ class_size += ik->local_interfaces()->size();
+ class_size += ik->transitive_interfaces()->size();
+ // We do not have to count implementors, since we only store one!
+ class_size += ik->fields()->size();
+ }
+ }
+
+ static void do_method(methodOop m) {
+ nmethods++;
+ method_size += m->size();
+ // class loader uses same objArray for empty vectors, so don't count these
+ if (m->exception_table()->length() != 0) method_size += m->exception_table()->size();
+ if (m->has_stackmap_table()) {
+ method_size += m->stackmap_data()->size();
+ }
+
+ methodDataOop mdo = m->method_data();
+ if (mdo != NULL) {
+ nmethoddata++;
+ methoddata_size += mdo->size();
+ }
+ }
+
+ public:
+ static void print() {
+ SystemDictionary::classes_do(do_class);
+ SystemDictionary::methods_do(do_method);
+ tty->print_cr("Class statistics:");
+ tty->print_cr("%d classes (%d bytes)", nclasses, class_size * oopSize);
+ tty->print_cr("%d methods (%d bytes = %d base + %d debug info)", nmethods,
+ (method_size + debug_size) * oopSize, method_size * oopSize, debug_size * oopSize);
+ tty->print_cr("%d methoddata (%d bytes)", nmethoddata, methoddata_size * oopSize);
+ }
+};
+
+
+int ClassStatistics::nclasses = 0;
+int ClassStatistics::nmethods = 0;
+int ClassStatistics::nmethoddata = 0;
+int ClassStatistics::class_size = 0;
+int ClassStatistics::method_size = 0;
+int ClassStatistics::debug_size = 0;
+int ClassStatistics::methoddata_size = 0;
+
+void SystemDictionary::print_class_statistics() {
+ ResourceMark rm;
+ ClassStatistics::print();
+}
+
+
+class MethodStatistics: AllStatic {
+ public:
+ enum {
+ max_parameter_size = 10
+ };
+ private:
+
+ static int _number_of_methods;
+ static int _number_of_final_methods;
+ static int _number_of_static_methods;
+ static int _number_of_native_methods;
+ static int _number_of_synchronized_methods;
+ static int _number_of_profiled_methods;
+ static int _number_of_bytecodes;
+ static int _parameter_size_profile[max_parameter_size];
+ static int _bytecodes_profile[Bytecodes::number_of_java_codes];
+
+ static void initialize() {
+ _number_of_methods = 0;
+ _number_of_final_methods = 0;
+ _number_of_static_methods = 0;
+ _number_of_native_methods = 0;
+ _number_of_synchronized_methods = 0;
+ _number_of_profiled_methods = 0;
+ _number_of_bytecodes = 0;
+ for (int i = 0; i < max_parameter_size ; i++) _parameter_size_profile[i] = 0;
+ for (int j = 0; j < Bytecodes::number_of_java_codes; j++) _bytecodes_profile [j] = 0;
+ };
+
+ static void do_method(methodOop m) {
+ _number_of_methods++;
+ // collect flag info
+ if (m->is_final() ) _number_of_final_methods++;
+ if (m->is_static() ) _number_of_static_methods++;
+ if (m->is_native() ) _number_of_native_methods++;
+ if (m->is_synchronized()) _number_of_synchronized_methods++;
+ if (m->method_data() != NULL) _number_of_profiled_methods++;
+ // collect parameter size info (add one for receiver, if any)
+ _parameter_size_profile[MIN2(m->size_of_parameters() + (m->is_static() ? 0 : 1), max_parameter_size - 1)]++;
+ // collect bytecodes info
+ {
+ Thread *thread = Thread::current();
+ HandleMark hm(thread);
+ BytecodeStream s(methodHandle(thread, m));
+ Bytecodes::Code c;
+ while ((c = s.next()) >= 0) {
+ _number_of_bytecodes++;
+ _bytecodes_profile[c]++;
+ }
+ }
+ }
+
+ public:
+ static void print() {
+ initialize();
+ SystemDictionary::methods_do(do_method);
+ // generate output
+ tty->cr();
+ tty->print_cr("Method statistics (static):");
+ // flag distribution
+ tty->cr();
+ tty->print_cr("%6d final methods %6.1f%%", _number_of_final_methods , _number_of_final_methods * 100.0F / _number_of_methods);
+ tty->print_cr("%6d static methods %6.1f%%", _number_of_static_methods , _number_of_static_methods * 100.0F / _number_of_methods);
+ tty->print_cr("%6d native methods %6.1f%%", _number_of_native_methods , _number_of_native_methods * 100.0F / _number_of_methods);
+ tty->print_cr("%6d synchronized methods %6.1f%%", _number_of_synchronized_methods, _number_of_synchronized_methods * 100.0F / _number_of_methods);
+ tty->print_cr("%6d profiled methods %6.1f%%", _number_of_profiled_methods, _number_of_profiled_methods * 100.0F / _number_of_methods);
+ // parameter size profile
+ tty->cr();
+ { int tot = 0;
+ int avg = 0;
+ for (int i = 0; i < max_parameter_size; i++) {
+ int n = _parameter_size_profile[i];
+ tot += n;
+ avg += n*i;
+ tty->print_cr("parameter size = %1d: %6d methods %5.1f%%", i, n, n * 100.0F / _number_of_methods);
+ }
+ assert(tot == _number_of_methods, "should be the same");
+ tty->print_cr(" %6d methods 100.0%%", _number_of_methods);
+ tty->print_cr("(average parameter size = %3.1f including receiver, if any)", (float)avg / _number_of_methods);
+ }
+ // bytecodes profile
+ tty->cr();
+ { int tot = 0;
+ for (int i = 0; i < Bytecodes::number_of_java_codes; i++) {
+ if (Bytecodes::is_defined(i)) {
+ Bytecodes::Code c = Bytecodes::cast(i);
+ int n = _bytecodes_profile[c];
+ tot += n;
+ tty->print_cr("%9d %7.3f%% %s", n, n * 100.0F / _number_of_bytecodes, Bytecodes::name(c));
+ }
+ }
+ assert(tot == _number_of_bytecodes, "should be the same");
+ tty->print_cr("%9d 100.000%%", _number_of_bytecodes);
+ }
+ tty->cr();
+ }
+};
+
+int MethodStatistics::_number_of_methods;
+int MethodStatistics::_number_of_final_methods;
+int MethodStatistics::_number_of_static_methods;
+int MethodStatistics::_number_of_native_methods;
+int MethodStatistics::_number_of_synchronized_methods;
+int MethodStatistics::_number_of_profiled_methods;
+int MethodStatistics::_number_of_bytecodes;
+int MethodStatistics::_parameter_size_profile[MethodStatistics::max_parameter_size];
+int MethodStatistics::_bytecodes_profile[Bytecodes::number_of_java_codes];
+
+
+void SystemDictionary::print_method_statistics() {
+ MethodStatistics::print();
+}
+
+#endif // PRODUCT