/* * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include "precompiled.hpp" #include "classfile/classFileParser.hpp" #include "classfile/javaClasses.hpp" #include "classfile/systemDictionary.hpp" #include "classfile/verifier.hpp" #include "classfile/vmSymbols.hpp" #include "code/dependencyContext.hpp" #include "compiler/compileBroker.hpp" #include "gc/shared/collectedHeap.inline.hpp" #include "gc/shared/specialized_oop_closures.hpp" #include "interpreter/oopMapCache.hpp" #include "interpreter/rewriter.hpp" #include "jvmtifiles/jvmti.h" #include "memory/heapInspection.hpp" #include "memory/iterator.inline.hpp" #include "memory/metadataFactory.hpp" #include "memory/oopFactory.hpp" #include "oops/fieldStreams.hpp" #include "oops/instanceClassLoaderKlass.hpp" #include "oops/instanceKlass.inline.hpp" #include "oops/instanceMirrorKlass.hpp" #include "oops/instanceOop.hpp" #include "oops/klass.inline.hpp" #include "oops/method.hpp" #include "oops/oop.inline.hpp" #include "oops/symbol.hpp" #include "prims/jvmtiExport.hpp" #include "prims/jvmtiRedefineClasses.hpp" #include "prims/jvmtiRedefineClassesTrace.hpp" #include "prims/jvmtiThreadState.hpp" #include "prims/methodComparator.hpp" #include "runtime/atomic.inline.hpp" #include "runtime/fieldDescriptor.hpp" #include "runtime/handles.inline.hpp" #include "runtime/javaCalls.hpp" #include "runtime/mutexLocker.hpp" #include "runtime/orderAccess.inline.hpp" #include "runtime/thread.inline.hpp" #include "services/classLoadingService.hpp" #include "services/threadService.hpp" #include "utilities/dtrace.hpp" #include "utilities/macros.hpp" #include "logging/log.hpp" #ifdef COMPILER1 #include "c1/c1_Compiler.hpp" #endif #ifdef DTRACE_ENABLED #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \ { \ char* data = NULL; \ int len = 0; \ Symbol* name = (clss)->name(); \ if (name != NULL) { \ data = (char*)name->bytes(); \ len = name->utf8_length(); \ } \ HOTSPOT_CLASS_INITIALIZATION_##type( \ data, len, (clss)->class_loader(), thread_type); \ } #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \ { \ char* data = NULL; \ int len = 0; \ Symbol* name = (clss)->name(); \ if (name != NULL) { \ data = (char*)name->bytes(); \ len = name->utf8_length(); \ } \ HOTSPOT_CLASS_INITIALIZATION_##type( \ data, len, (clss)->class_loader(), thread_type, wait); \ } #else // ndef DTRACE_ENABLED #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) #endif // ndef DTRACE_ENABLED volatile int InstanceKlass::_total_instanceKlass_count = 0; static inline bool is_class_loader(const Symbol* class_name, const ClassFileParser& parser) { assert(class_name != NULL, "invariant"); if (class_name == vmSymbols::java_lang_ClassLoader()) { return true; } if (SystemDictionary::ClassLoader_klass_loaded()) { const Klass* const super_klass = parser.super_klass(); if (super_klass != NULL) { if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) { return true; } } } return false; } InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) { const int size = InstanceKlass::size(parser.vtable_size(), parser.itable_size(), nonstatic_oop_map_size(parser.total_oop_map_count()), parser.is_interface(), parser.is_anonymous()); const Symbol* const class_name = parser.class_name(); assert(class_name != NULL, "invariant"); ClassLoaderData* loader_data = parser.loader_data(); assert(loader_data != NULL, "invariant"); InstanceKlass* ik; // Allocation if (REF_NONE == parser.reference_type()) { if (class_name == vmSymbols::java_lang_Class()) { // mirror ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser); } else if (is_class_loader(class_name, parser)) { // class loader ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser); } else { // normal ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other); } } else { // reference ik = new (loader_data, size, THREAD) InstanceRefKlass(parser); } // Check for pending exception before adding to the loader data and incrementing // class count. Can get OOM here. if (HAS_PENDING_EXCEPTION) { return NULL; } assert(ik != NULL, "invariant"); const bool publicize = !parser.is_internal(); // Add all classes to our internal class loader list here, // including classes in the bootstrap (NULL) class loader. loader_data->add_class(ik, publicize); Atomic::inc(&_total_instanceKlass_count); return ik; } // copy method ordering from resource area to Metaspace void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) { if (m != NULL) { // allocate a new array and copy contents (memcpy?) _method_ordering = MetadataFactory::new_array(class_loader_data(), m->length(), CHECK); for (int i = 0; i < m->length(); i++) { _method_ordering->at_put(i, m->at(i)); } } else { _method_ordering = Universe::the_empty_int_array(); } } // create a new array of vtable_indices for default methods Array* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { Array* vtable_indices = MetadataFactory::new_array(class_loader_data(), len, CHECK_NULL); assert(default_vtable_indices() == NULL, "only create once"); set_default_vtable_indices(vtable_indices); return vtable_indices; } InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) : _static_field_size(parser.static_field_size()), _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())), _vtable_len(parser.vtable_size()), _itable_len(parser.itable_size()), _reference_type(parser.reference_type()) { set_kind(kind); set_access_flags(parser.access_flags()); set_is_anonymous(parser.is_anonymous()); set_layout_helper(Klass::instance_layout_helper(parser.layout_size(), false)); assert(NULL == _methods, "underlying memory not zeroed?"); assert(is_instance_klass(), "is layout incorrect?"); assert(size_helper() == parser.layout_size(), "incorrect size_helper?"); } void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, Array* methods) { if (methods != NULL && methods != Universe::the_empty_method_array() && !methods->is_shared()) { for (int i = 0; i < methods->length(); i++) { Method* method = methods->at(i); if (method == NULL) continue; // maybe null if error processing // Only want to delete methods that are not executing for RedefineClasses. // The previous version will point to them so they're not totally dangling assert (!method->on_stack(), "shouldn't be called with methods on stack"); MetadataFactory::free_metadata(loader_data, method); } MetadataFactory::free_array(loader_data, methods); } } void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, const Klass* super_klass, Array* local_interfaces, Array* transitive_interfaces) { // Only deallocate transitive interfaces if not empty, same as super class // or same as local interfaces. See code in parseClassFile. Array* ti = transitive_interfaces; if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) { // check that the interfaces don't come from super class Array* sti = (super_klass == NULL) ? NULL : InstanceKlass::cast(super_klass)->transitive_interfaces(); if (ti != sti && ti != NULL && !ti->is_shared()) { MetadataFactory::free_array(loader_data, ti); } } // local interfaces can be empty if (local_interfaces != Universe::the_empty_klass_array() && local_interfaces != NULL && !local_interfaces->is_shared()) { MetadataFactory::free_array(loader_data, local_interfaces); } } // This function deallocates the metadata and C heap pointers that the // InstanceKlass points to. void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { // Orphan the mirror first, CMS thinks it's still live. if (java_mirror() != NULL) { java_lang_Class::set_klass(java_mirror(), NULL); } // Need to take this class off the class loader data list. loader_data->remove_class(this); // The array_klass for this class is created later, after error handling. // For class redefinition, we keep the original class so this scratch class // doesn't have an array class. Either way, assert that there is nothing // to deallocate. assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet"); // Release C heap allocated data that this might point to, which includes // reference counting symbol names. release_C_heap_structures(); deallocate_methods(loader_data, methods()); set_methods(NULL); if (method_ordering() != NULL && method_ordering() != Universe::the_empty_int_array() && !method_ordering()->is_shared()) { MetadataFactory::free_array(loader_data, method_ordering()); } set_method_ordering(NULL); // default methods can be empty if (default_methods() != NULL && default_methods() != Universe::the_empty_method_array() && !default_methods()->is_shared()) { MetadataFactory::free_array(loader_data, default_methods()); } // Do NOT deallocate the default methods, they are owned by superinterfaces. set_default_methods(NULL); // default methods vtable indices can be empty if (default_vtable_indices() != NULL && !default_vtable_indices()->is_shared()) { MetadataFactory::free_array(loader_data, default_vtable_indices()); } set_default_vtable_indices(NULL); // This array is in Klass, but remove it with the InstanceKlass since // this place would be the only caller and it can share memory with transitive // interfaces. if (secondary_supers() != NULL && secondary_supers() != Universe::the_empty_klass_array() && secondary_supers() != transitive_interfaces() && !secondary_supers()->is_shared()) { MetadataFactory::free_array(loader_data, secondary_supers()); } set_secondary_supers(NULL); deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); set_transitive_interfaces(NULL); set_local_interfaces(NULL); if (fields() != NULL && !fields()->is_shared()) { MetadataFactory::free_array(loader_data, fields()); } set_fields(NULL, 0); // If a method from a redefined class is using this constant pool, don't // delete it, yet. The new class's previous version will point to this. if (constants() != NULL) { assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); if (!constants()->is_shared()) { MetadataFactory::free_metadata(loader_data, constants()); } // Delete any cached resolution errors for the constant pool SystemDictionary::delete_resolution_error(constants()); set_constants(NULL); } if (inner_classes() != NULL && inner_classes() != Universe::the_empty_short_array() && !inner_classes()->is_shared()) { MetadataFactory::free_array(loader_data, inner_classes()); } set_inner_classes(NULL); // We should deallocate the Annotations instance if it's not in shared spaces. if (annotations() != NULL && !annotations()->is_shared()) { MetadataFactory::free_metadata(loader_data, annotations()); } set_annotations(NULL); } bool InstanceKlass::should_be_initialized() const { return !is_initialized(); } klassVtable* InstanceKlass::vtable() const { return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size()); } klassItable* InstanceKlass::itable() const { return new klassItable(instanceKlassHandle(this)); } void InstanceKlass::eager_initialize(Thread *thread) { if (!EagerInitialization) return; if (this->is_not_initialized()) { // abort if the the class has a class initializer if (this->class_initializer() != NULL) return; // abort if it is java.lang.Object (initialization is handled in genesis) Klass* super = this->super(); if (super == NULL) return; // abort if the super class should be initialized if (!InstanceKlass::cast(super)->is_initialized()) return; // call body to expose the this pointer instanceKlassHandle this_k(thread, this); eager_initialize_impl(this_k); } } // JVMTI spec thinks there are signers and protection domain in the // instanceKlass. These accessors pretend these fields are there. // The hprof specification also thinks these fields are in InstanceKlass. oop InstanceKlass::protection_domain() const { // return the protection_domain from the mirror return java_lang_Class::protection_domain(java_mirror()); } // To remove these from requires an incompatible change and CCC request. objArrayOop InstanceKlass::signers() const { // return the signers from the mirror return java_lang_Class::signers(java_mirror()); } oop InstanceKlass::init_lock() const { // return the init lock from the mirror oop lock = java_lang_Class::init_lock(java_mirror()); // Prevent reordering with any access of initialization state OrderAccess::loadload(); assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state "only fully initialized state can have a null lock"); return lock; } // Set the initialization lock to null so the object can be GC'ed. Any racing // threads to get this lock will see a null lock and will not lock. // That's okay because they all check for initialized state after getting // the lock and return. void InstanceKlass::fence_and_clear_init_lock() { // make sure previous stores are all done, notably the init_state. OrderAccess::storestore(); java_lang_Class::set_init_lock(java_mirror(), NULL); assert(!is_not_initialized(), "class must be initialized now"); } void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) { EXCEPTION_MARK; oop init_lock = this_k->init_lock(); ObjectLocker ol(init_lock, THREAD, init_lock != NULL); // abort if someone beat us to the initialization if (!this_k->is_not_initialized()) return; // note: not equivalent to is_initialized() ClassState old_state = this_k->init_state(); link_class_impl(this_k, true, THREAD); if (HAS_PENDING_EXCEPTION) { CLEAR_PENDING_EXCEPTION; // Abort if linking the class throws an exception. // Use a test to avoid redundantly resetting the state if there's // no change. Set_init_state() asserts that state changes make // progress, whereas here we might just be spinning in place. if( old_state != this_k->_init_state ) this_k->set_init_state (old_state); } else { // linking successfull, mark class as initialized this_k->set_init_state (fully_initialized); this_k->fence_and_clear_init_lock(); // trace if (log_is_enabled(Info, classinit)) { ResourceMark rm(THREAD); log_info(classinit)("[Initialized %s without side effects]", this_k->external_name()); } } } // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization // process. The step comments refers to the procedure described in that section. // Note: implementation moved to static method to expose the this pointer. void InstanceKlass::initialize(TRAPS) { if (this->should_be_initialized()) { HandleMark hm(THREAD); instanceKlassHandle this_k(THREAD, this); initialize_impl(this_k, CHECK); // Note: at this point the class may be initialized // OR it may be in the state of being initialized // in case of recursive initialization! } else { assert(is_initialized(), "sanity check"); } } bool InstanceKlass::verify_code( instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) { // 1) Verify the bytecodes Verifier::Mode mode = throw_verifyerror ? Verifier::ThrowException : Verifier::NoException; return Verifier::verify(this_k, mode, this_k->should_verify_class(), THREAD); } // Used exclusively by the shared spaces dump mechanism to prevent // classes mapped into the shared regions in new VMs from appearing linked. void InstanceKlass::unlink_class() { assert(is_linked(), "must be linked"); _init_state = loaded; } void InstanceKlass::link_class(TRAPS) { assert(is_loaded(), "must be loaded"); if (!is_linked()) { HandleMark hm(THREAD); instanceKlassHandle this_k(THREAD, this); link_class_impl(this_k, true, CHECK); } } // Called to verify that a class can link during initialization, without // throwing a VerifyError. bool InstanceKlass::link_class_or_fail(TRAPS) { assert(is_loaded(), "must be loaded"); if (!is_linked()) { HandleMark hm(THREAD); instanceKlassHandle this_k(THREAD, this); link_class_impl(this_k, false, CHECK_false); } return is_linked(); } bool InstanceKlass::link_class_impl( instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) { // check for error state if (this_k->is_in_error_state()) { ResourceMark rm(THREAD); THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(), this_k->external_name(), false); } // return if already verified if (this_k->is_linked()) { return true; } // Timing // timer handles recursion assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); JavaThread* jt = (JavaThread*)THREAD; // link super class before linking this class instanceKlassHandle super(THREAD, this_k->super()); if (super.not_null()) { if (super->is_interface()) { // check if super class is an interface ResourceMark rm(THREAD); Exceptions::fthrow( THREAD_AND_LOCATION, vmSymbols::java_lang_IncompatibleClassChangeError(), "class %s has interface %s as super class", this_k->external_name(), super->external_name() ); return false; } link_class_impl(super, throw_verifyerror, CHECK_false); } // link all interfaces implemented by this class before linking this class Array* interfaces = this_k->local_interfaces(); int num_interfaces = interfaces->length(); for (int index = 0; index < num_interfaces; index++) { HandleMark hm(THREAD); instanceKlassHandle ih(THREAD, interfaces->at(index)); link_class_impl(ih, throw_verifyerror, CHECK_false); } // in case the class is linked in the process of linking its superclasses if (this_k->is_linked()) { return true; } // trace only the link time for this klass that includes // the verification time PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), ClassLoader::perf_class_link_selftime(), ClassLoader::perf_classes_linked(), jt->get_thread_stat()->perf_recursion_counts_addr(), jt->get_thread_stat()->perf_timers_addr(), PerfClassTraceTime::CLASS_LINK); // verification & rewriting { oop init_lock = this_k->init_lock(); ObjectLocker ol(init_lock, THREAD, init_lock != NULL); // rewritten will have been set if loader constraint error found // on an earlier link attempt // don't verify or rewrite if already rewritten if (!this_k->is_linked()) { if (!this_k->is_rewritten()) { { bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD); if (!verify_ok) { return false; } } // Just in case a side-effect of verify linked this class already // (which can sometimes happen since the verifier loads classes // using custom class loaders, which are free to initialize things) if (this_k->is_linked()) { return true; } // also sets rewritten this_k->rewrite_class(CHECK_false); } // relocate jsrs and link methods after they are all rewritten this_k->link_methods(CHECK_false); // Initialize the vtable and interface table after // methods have been rewritten since rewrite may // fabricate new Method*s. // also does loader constraint checking if (!this_k()->is_shared()) { ResourceMark rm(THREAD); this_k->vtable()->initialize_vtable(true, CHECK_false); this_k->itable()->initialize_itable(true, CHECK_false); } #ifdef ASSERT else { ResourceMark rm(THREAD); this_k->vtable()->verify(tty, true); // In case itable verification is ever added. // this_k->itable()->verify(tty, true); } #endif this_k->set_init_state(linked); if (JvmtiExport::should_post_class_prepare()) { Thread *thread = THREAD; assert(thread->is_Java_thread(), "thread->is_Java_thread()"); JvmtiExport::post_class_prepare((JavaThread *) thread, this_k()); } } } return true; } // Rewrite the byte codes of all of the methods of a class. // The rewriter must be called exactly once. Rewriting must happen after // verification but before the first method of the class is executed. void InstanceKlass::rewrite_class(TRAPS) { assert(is_loaded(), "must be loaded"); instanceKlassHandle this_k(THREAD, this); if (this_k->is_rewritten()) { assert(this_k()->is_shared(), "rewriting an unshared class?"); return; } Rewriter::rewrite(this_k, CHECK); this_k->set_rewritten(); } // Now relocate and link method entry points after class is rewritten. // This is outside is_rewritten flag. In case of an exception, it can be // executed more than once. void InstanceKlass::link_methods(TRAPS) { int len = methods()->length(); for (int i = len-1; i >= 0; i--) { methodHandle m(THREAD, methods()->at(i)); // Set up method entry points for compiler and interpreter . m->link_method(m, CHECK); } } // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) void InstanceKlass::initialize_super_interfaces(instanceKlassHandle this_k, TRAPS) { if (this_k->has_default_methods()) { for (int i = 0; i < this_k->local_interfaces()->length(); ++i) { Klass* iface = this_k->local_interfaces()->at(i); InstanceKlass* ik = InstanceKlass::cast(iface); if (ik->should_be_initialized()) { if (ik->has_default_methods()) { ik->initialize_super_interfaces(ik, THREAD); } // Only initialize() interfaces that "declare" concrete methods. // has_default_methods drives searching superinterfaces since it // means has_default_methods in its superinterface hierarchy if (!HAS_PENDING_EXCEPTION && ik->declares_default_methods()) { ik->initialize(THREAD); } if (HAS_PENDING_EXCEPTION) { Handle e(THREAD, PENDING_EXCEPTION); CLEAR_PENDING_EXCEPTION; { EXCEPTION_MARK; // Locks object, set state, and notify all waiting threads this_k->set_initialization_state_and_notify( initialization_error, THREAD); // ignore any exception thrown, superclass initialization error is // thrown below CLEAR_PENDING_EXCEPTION; } THROW_OOP(e()); } } } } } void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) { // Make sure klass is linked (verified) before initialization // A class could already be verified, since it has been reflected upon. this_k->link_class(CHECK); DTRACE_CLASSINIT_PROBE(required, this_k(), -1); bool wait = false; // refer to the JVM book page 47 for description of steps // Step 1 { oop init_lock = this_k->init_lock(); ObjectLocker ol(init_lock, THREAD, init_lock != NULL); Thread *self = THREAD; // it's passed the current thread // Step 2 // If we were to use wait() instead of waitInterruptibly() then // we might end up throwing IE from link/symbol resolution sites // that aren't expected to throw. This would wreak havoc. See 6320309. while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) { wait = true; ol.waitUninterruptibly(CHECK); } // Step 3 if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) { DTRACE_CLASSINIT_PROBE_WAIT(recursive, this_k(), -1,wait); return; } // Step 4 if (this_k->is_initialized()) { DTRACE_CLASSINIT_PROBE_WAIT(concurrent, this_k(), -1,wait); return; } // Step 5 if (this_k->is_in_error_state()) { DTRACE_CLASSINIT_PROBE_WAIT(erroneous, this_k(), -1,wait); ResourceMark rm(THREAD); const char* desc = "Could not initialize class "; const char* className = this_k->external_name(); size_t msglen = strlen(desc) + strlen(className) + 1; char* message = NEW_RESOURCE_ARRAY(char, msglen); if (NULL == message) { // Out of memory: can't create detailed error message THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className); } else { jio_snprintf(message, msglen, "%s%s", desc, className); THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message); } } // Step 6 this_k->set_init_state(being_initialized); this_k->set_init_thread(self); } // Step 7 Klass* super_klass = this_k->super(); if (super_klass != NULL && !this_k->is_interface() && super_klass->should_be_initialized()) { super_klass->initialize(THREAD); if (HAS_PENDING_EXCEPTION) { Handle e(THREAD, PENDING_EXCEPTION); CLEAR_PENDING_EXCEPTION; { EXCEPTION_MARK; this_k->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below } DTRACE_CLASSINIT_PROBE_WAIT(super__failed, this_k(), -1,wait); THROW_OOP(e()); } } // If C is an interface that declares a non-abstract, non-static method, // the initialization of a class (not an interface) that implements C directly or // indirectly. // Recursively initialize any superinterfaces that declare default methods // Only need to recurse if has_default_methods which includes declaring and // inheriting default methods if (!this_k->is_interface() && this_k->has_default_methods()) { this_k->initialize_super_interfaces(this_k, CHECK); } // Step 8 { assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl"); JavaThread* jt = (JavaThread*)THREAD; DTRACE_CLASSINIT_PROBE_WAIT(clinit, this_k(), -1,wait); // Timer includes any side effects of class initialization (resolution, // etc), but not recursive entry into call_class_initializer(). PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), ClassLoader::perf_class_init_selftime(), ClassLoader::perf_classes_inited(), jt->get_thread_stat()->perf_recursion_counts_addr(), jt->get_thread_stat()->perf_timers_addr(), PerfClassTraceTime::CLASS_CLINIT); this_k->call_class_initializer(THREAD); } // Step 9 if (!HAS_PENDING_EXCEPTION) { this_k->set_initialization_state_and_notify(fully_initialized, CHECK); { ResourceMark rm(THREAD); debug_only(this_k->vtable()->verify(tty, true);) } } else { // Step 10 and 11 Handle e(THREAD, PENDING_EXCEPTION); CLEAR_PENDING_EXCEPTION; // JVMTI has already reported the pending exception // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError JvmtiExport::clear_detected_exception((JavaThread*)THREAD); { EXCEPTION_MARK; this_k->set_initialization_state_and_notify(initialization_error, THREAD); CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below // JVMTI has already reported the pending exception // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError JvmtiExport::clear_detected_exception((JavaThread*)THREAD); } DTRACE_CLASSINIT_PROBE_WAIT(error, this_k(), -1,wait); if (e->is_a(SystemDictionary::Error_klass())) { THROW_OOP(e()); } else { JavaCallArguments args(e); THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), vmSymbols::throwable_void_signature(), &args); } } DTRACE_CLASSINIT_PROBE_WAIT(end, this_k(), -1,wait); } // Note: implementation moved to static method to expose the this pointer. void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { instanceKlassHandle kh(THREAD, this); set_initialization_state_and_notify_impl(kh, state, CHECK); } void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) { oop init_lock = this_k->init_lock(); ObjectLocker ol(init_lock, THREAD, init_lock != NULL); this_k->set_init_state(state); this_k->fence_and_clear_init_lock(); ol.notify_all(CHECK); } // The embedded _implementor field can only record one implementor. // When there are more than one implementors, the _implementor field // is set to the interface Klass* itself. Following are the possible // values for the _implementor field: // NULL - no implementor // implementor Klass* - one implementor // self - more than one implementor // // The _implementor field only exists for interfaces. void InstanceKlass::add_implementor(Klass* k) { assert(Compile_lock->owned_by_self(), ""); assert(is_interface(), "not interface"); // Filter out my subinterfaces. // (Note: Interfaces are never on the subklass list.) if (InstanceKlass::cast(k)->is_interface()) return; // Filter out subclasses whose supers already implement me. // (Note: CHA must walk subclasses of direct implementors // in order to locate indirect implementors.) Klass* sk = k->super(); if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this)) // We only need to check one immediate superclass, since the // implements_interface query looks at transitive_interfaces. // Any supers of the super have the same (or fewer) transitive_interfaces. return; Klass* ik = implementor(); if (ik == NULL) { set_implementor(k); } else if (ik != this) { // There is already an implementor. Use itself as an indicator of // more than one implementors. set_implementor(this); } // The implementor also implements the transitive_interfaces for (int index = 0; index < local_interfaces()->length(); index++) { InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k); } } void InstanceKlass::init_implementor() { if (is_interface()) { set_implementor(NULL); } } void InstanceKlass::process_interfaces(Thread *thread) { // link this class into the implementors list of every interface it implements for (int i = local_interfaces()->length() - 1; i >= 0; i--) { assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i)); assert(interf->is_interface(), "expected interface"); interf->add_implementor(this); } } bool InstanceKlass::can_be_primary_super_slow() const { if (is_interface()) return false; else return Klass::can_be_primary_super_slow(); } GrowableArray* InstanceKlass::compute_secondary_supers(int num_extra_slots) { // The secondaries are the implemented interfaces. Array* interfaces = transitive_interfaces(); int num_secondaries = num_extra_slots + interfaces->length(); if (num_secondaries == 0) { // Must share this for correct bootstrapping! set_secondary_supers(Universe::the_empty_klass_array()); return NULL; } else if (num_extra_slots == 0) { // The secondary super list is exactly the same as the transitive interfaces. // Redefine classes has to be careful not to delete this! set_secondary_supers(interfaces); return NULL; } else { // Copy transitive interfaces to a temporary growable array to be constructed // into the secondary super list with extra slots. GrowableArray* secondaries = new GrowableArray(interfaces->length()); for (int i = 0; i < interfaces->length(); i++) { secondaries->push(interfaces->at(i)); } return secondaries; } } bool InstanceKlass::compute_is_subtype_of(Klass* k) { if (k->is_interface()) { return implements_interface(k); } else { return Klass::compute_is_subtype_of(k); } } bool InstanceKlass::implements_interface(Klass* k) const { if (this == k) return true; assert(k->is_interface(), "should be an interface class"); for (int i = 0; i < transitive_interfaces()->length(); i++) { if (transitive_interfaces()->at(i) == k) { return true; } } return false; } bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { // Verify direct super interface if (this == k) return true; assert(k->is_interface(), "should be an interface class"); for (int i = 0; i < local_interfaces()->length(); i++) { if (local_interfaces()->at(i) == k) { return true; } } return false; } objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException()); if (length > arrayOopDesc::max_array_length(T_OBJECT)) { report_java_out_of_memory("Requested array size exceeds VM limit"); JvmtiExport::post_array_size_exhausted(); THROW_OOP_0(Universe::out_of_memory_error_array_size()); } int size = objArrayOopDesc::object_size(length); Klass* ak = array_klass(n, CHECK_NULL); KlassHandle h_ak (THREAD, ak); objArrayOop o = (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL); return o; } instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { if (TraceFinalizerRegistration) { tty->print("Registered "); i->print_value_on(tty); tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i)); } instanceHandle h_i(THREAD, i); // Pass the handle as argument, JavaCalls::call expects oop as jobjects JavaValue result(T_VOID); JavaCallArguments args(h_i); methodHandle mh (THREAD, Universe::finalizer_register_method()); JavaCalls::call(&result, mh, &args, CHECK_NULL); return h_i(); } instanceOop InstanceKlass::allocate_instance(TRAPS) { bool has_finalizer_flag = has_finalizer(); // Query before possible GC int size = size_helper(); // Query before forming handle. KlassHandle h_k(THREAD, this); instanceOop i; i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL); if (has_finalizer_flag && !RegisterFinalizersAtInit) { i = register_finalizer(i, CHECK_NULL); } return i; } void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { if (is_interface() || is_abstract()) { ResourceMark rm(THREAD); THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() : vmSymbols::java_lang_InstantiationException(), external_name()); } if (this == SystemDictionary::Class_klass()) { ResourceMark rm(THREAD); THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() : vmSymbols::java_lang_IllegalAccessException(), external_name()); } } Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) { instanceKlassHandle this_k(THREAD, this); return array_klass_impl(this_k, or_null, n, THREAD); } Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) { if (this_k->array_klasses() == NULL) { if (or_null) return NULL; ResourceMark rm; JavaThread *jt = (JavaThread *)THREAD; { // Atomic creation of array_klasses MutexLocker mc(Compile_lock, THREAD); // for vtables MutexLocker ma(MultiArray_lock, THREAD); // Check if update has already taken place if (this_k->array_klasses() == NULL) { Klass* k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL); this_k->set_array_klasses(k); } } } // _this will always be set at this point ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses(); if (or_null) { return oak->array_klass_or_null(n); } return oak->array_klass(n, THREAD); } Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) { return array_klass_impl(or_null, 1, THREAD); } void InstanceKlass::call_class_initializer(TRAPS) { instanceKlassHandle ik (THREAD, this); call_class_initializer_impl(ik, THREAD); } static int call_class_initializer_impl_counter = 0; // for debugging Method* InstanceKlass::class_initializer() { Method* clinit = find_method( vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); if (clinit != NULL && clinit->has_valid_initializer_flags()) { return clinit; } return NULL; } void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) { if (ReplayCompiles && (ReplaySuppressInitializers == 1 || ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) { // Hide the existence of the initializer for the purpose of replaying the compile return; } methodHandle h_method(THREAD, this_k->class_initializer()); assert(!this_k->is_initialized(), "we cannot initialize twice"); if (log_is_enabled(Info, classinit)) { ResourceMark rm; outputStream* log = LogHandle(classinit)::info_stream(); log->print("%d Initializing ", call_class_initializer_impl_counter++); this_k->name()->print_value_on(log); log->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this_k())); } if (h_method() != NULL) { JavaCallArguments args; // No arguments JavaValue result(T_VOID); JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) } } void InstanceKlass::mask_for(const methodHandle& method, int bci, InterpreterOopMap* entry_for) { // Dirty read, then double-check under a lock. if (_oop_map_cache == NULL) { // Otherwise, allocate a new one. MutexLocker x(OopMapCacheAlloc_lock); // First time use. Allocate a cache in C heap if (_oop_map_cache == NULL) { // Release stores from OopMapCache constructor before assignment // to _oop_map_cache. C++ compilers on ppc do not emit the // required memory barrier only because of the volatile // qualifier of _oop_map_cache. OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache()); } } // _oop_map_cache is constant after init; lookup below does is own locking. _oop_map_cache->lookup(method, bci, entry_for); } bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { for (JavaFieldStream fs(this); !fs.done(); fs.next()) { Symbol* f_name = fs.name(); Symbol* f_sig = fs.signature(); if (f_name == name && f_sig == sig) { fd->reinitialize(const_cast(this), fs.index()); return true; } } return false; } Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { const int n = local_interfaces()->length(); for (int i = 0; i < n; i++) { Klass* intf1 = local_interfaces()->at(i); assert(intf1->is_interface(), "just checking type"); // search for field in current interface if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { assert(fd->is_static(), "interface field must be static"); return intf1; } // search for field in direct superinterfaces Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); if (intf2 != NULL) return intf2; } // otherwise field lookup fails return NULL; } Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { // search order according to newest JVM spec (5.4.3.2, p.167). // 1) search for field in current klass if (find_local_field(name, sig, fd)) { return const_cast(this); } // 2) search for field recursively in direct superinterfaces { Klass* intf = find_interface_field(name, sig, fd); if (intf != NULL) return intf; } // 3) apply field lookup recursively if superclass exists { Klass* supr = super(); if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd); } // 4) otherwise field lookup fails return NULL; } Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { // search order according to newest JVM spec (5.4.3.2, p.167). // 1) search for field in current klass if (find_local_field(name, sig, fd)) { if (fd->is_static() == is_static) return const_cast(this); } // 2) search for field recursively in direct superinterfaces if (is_static) { Klass* intf = find_interface_field(name, sig, fd); if (intf != NULL) return intf; } // 3) apply field lookup recursively if superclass exists { Klass* supr = super(); if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); } // 4) otherwise field lookup fails return NULL; } bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { for (JavaFieldStream fs(this); !fs.done(); fs.next()) { if (fs.offset() == offset) { fd->reinitialize(const_cast(this), fs.index()); if (fd->is_static() == is_static) return true; } } return false; } bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { Klass* klass = const_cast(this); while (klass != NULL) { if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { return true; } klass = klass->super(); } return false; } void InstanceKlass::methods_do(void f(Method* method)) { // Methods aren't stable until they are loaded. This can be read outside // a lock through the ClassLoaderData for profiling if (!is_loaded()) { return; } int len = methods()->length(); for (int index = 0; index < len; index++) { Method* m = methods()->at(index); assert(m->is_method(), "must be method"); f(m); } } void InstanceKlass::do_local_static_fields(FieldClosure* cl) { for (JavaFieldStream fs(this); !fs.done(); fs.next()) { if (fs.access_flags().is_static()) { fieldDescriptor& fd = fs.field_descriptor(); cl->do_field(&fd); } } } void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { instanceKlassHandle h_this(THREAD, this); do_local_static_fields_impl(h_this, f, mirror, CHECK); } void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k, void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) { for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) { if (fs.access_flags().is_static()) { fieldDescriptor& fd = fs.field_descriptor(); f(&fd, mirror, CHECK); } } } static int compare_fields_by_offset(int* a, int* b) { return a[0] - b[0]; } void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { InstanceKlass* super = superklass(); if (super != NULL) { super->do_nonstatic_fields(cl); } fieldDescriptor fd; int length = java_fields_count(); // In DebugInfo nonstatic fields are sorted by offset. int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass); int j = 0; for (int i = 0; i < length; i += 1) { fd.reinitialize(this, i); if (!fd.is_static()) { fields_sorted[j + 0] = fd.offset(); fields_sorted[j + 1] = i; j += 2; } } if (j > 0) { length = j; // _sort_Fn is defined in growableArray.hpp. qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset); for (int i = 0; i < length; i += 2) { fd.reinitialize(this, fields_sorted[i + 1]); assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields"); cl->do_field(&fd); } } FREE_C_HEAP_ARRAY(int, fields_sorted); } void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) { if (array_klasses() != NULL) ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD); } void InstanceKlass::array_klasses_do(void f(Klass* k)) { if (array_klasses() != NULL) ArrayKlass::cast(array_klasses())->array_klasses_do(f); } #ifdef ASSERT static int linear_search(const Array* methods, const Symbol* name, const Symbol* signature) { const int len = methods->length(); for (int index = 0; index < len; index++) { const Method* const m = methods->at(index); assert(m->is_method(), "must be method"); if (m->signature() == signature && m->name() == name) { return index; } } return -1; } #endif static int binary_search(const Array* methods, const Symbol* name) { int len = methods->length(); // methods are sorted, so do binary search int l = 0; int h = len - 1; while (l <= h) { int mid = (l + h) >> 1; Method* m = methods->at(mid); assert(m->is_method(), "must be method"); int res = m->name()->fast_compare(name); if (res == 0) { return mid; } else if (res < 0) { l = mid + 1; } else { h = mid - 1; } } return -1; } // find_method looks up the name/signature in the local methods array Method* InstanceKlass::find_method(const Symbol* name, const Symbol* signature) const { return find_method_impl(name, signature, find_overpass, find_static, find_private); } Method* InstanceKlass::find_method_impl(const Symbol* name, const Symbol* signature, OverpassLookupMode overpass_mode, StaticLookupMode static_mode, PrivateLookupMode private_mode) const { return InstanceKlass::find_method_impl(methods(), name, signature, overpass_mode, static_mode, private_mode); } // find_instance_method looks up the name/signature in the local methods array // and skips over static methods Method* InstanceKlass::find_instance_method(const Array* methods, const Symbol* name, const Symbol* signature) { Method* const meth = InstanceKlass::find_method_impl(methods, name, signature, find_overpass, skip_static, find_private); assert(((meth == NULL) || !meth->is_static()), "find_instance_method should have skipped statics"); return meth; } // find_instance_method looks up the name/signature in the local methods array // and skips over static methods Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const { return InstanceKlass::find_instance_method(methods(), name, signature); } // Find looks up the name/signature in the local methods array // and filters on the overpass, static and private flags // This returns the first one found // note that the local methods array can have up to one overpass, one static // and one instance (private or not) with the same name/signature Method* InstanceKlass::find_local_method(const Symbol* name, const Symbol* signature, OverpassLookupMode overpass_mode, StaticLookupMode static_mode, PrivateLookupMode private_mode) const { return InstanceKlass::find_method_impl(methods(), name, signature, overpass_mode, static_mode, private_mode); } // Find looks up the name/signature in the local methods array // and filters on the overpass, static and private flags // This returns the first one found // note that the local methods array can have up to one overpass, one static // and one instance (private or not) with the same name/signature Method* InstanceKlass::find_local_method(const Array* methods, const Symbol* name, const Symbol* signature, OverpassLookupMode overpass_mode, StaticLookupMode static_mode, PrivateLookupMode private_mode) { return InstanceKlass::find_method_impl(methods, name, signature, overpass_mode, static_mode, private_mode); } Method* InstanceKlass::find_method(const Array* methods, const Symbol* name, const Symbol* signature) { return InstanceKlass::find_method_impl(methods, name, signature, find_overpass, find_static, find_private); } Method* InstanceKlass::find_method_impl(const Array* methods, const Symbol* name, const Symbol* signature, OverpassLookupMode overpass_mode, StaticLookupMode static_mode, PrivateLookupMode private_mode) { int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); return hit >= 0 ? methods->at(hit): NULL; } // true if method matches signature and conforms to skipping_X conditions. static bool method_matches(const Method* m, const Symbol* signature, bool skipping_overpass, bool skipping_static, bool skipping_private) { return ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass()) && (!skipping_static || !m->is_static()) && (!skipping_private || !m->is_private())); } // Used directly for default_methods to find the index into the // default_vtable_indices, and indirectly by find_method // find_method_index looks in the local methods array to return the index // of the matching name/signature. If, overpass methods are being ignored, // the search continues to find a potential non-overpass match. This capability // is important during method resolution to prefer a static method, for example, // over an overpass method. // There is the possibility in any _method's array to have the same name/signature // for a static method, an overpass method and a local instance method // To correctly catch a given method, the search criteria may need // to explicitly skip the other two. For local instance methods, it // is often necessary to skip private methods int InstanceKlass::find_method_index(const Array* methods, const Symbol* name, const Symbol* signature, OverpassLookupMode overpass_mode, StaticLookupMode static_mode, PrivateLookupMode private_mode) { const bool skipping_overpass = (overpass_mode == skip_overpass); const bool skipping_static = (static_mode == skip_static); const bool skipping_private = (private_mode == skip_private); const int hit = binary_search(methods, name); if (hit != -1) { const Method* const m = methods->at(hit); // Do linear search to find matching signature. First, quick check // for common case, ignoring overpasses if requested. if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { return hit; } // search downwards through overloaded methods int i; for (i = hit - 1; i >= 0; --i) { const Method* const m = methods->at(i); assert(m->is_method(), "must be method"); if (m->name() != name) { break; } if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { return i; } } // search upwards for (i = hit + 1; i < methods->length(); ++i) { const Method* const m = methods->at(i); assert(m->is_method(), "must be method"); if (m->name() != name) { break; } if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { return i; } } // not found #ifdef ASSERT const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : linear_search(methods, name, signature); assert(-1 == index, "binary search should have found entry %d", index); #endif } return -1; } int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const { return find_method_by_name(methods(), name, end); } int InstanceKlass::find_method_by_name(const Array* methods, const Symbol* name, int* end_ptr) { assert(end_ptr != NULL, "just checking"); int start = binary_search(methods, name); int end = start + 1; if (start != -1) { while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; while (end < methods->length() && (methods->at(end))->name() == name) ++end; *end_ptr = end; return start; } return -1; } // uncached_lookup_method searches both the local class methods array and all // superclasses methods arrays, skipping any overpass methods in superclasses. Method* InstanceKlass::uncached_lookup_method(const Symbol* name, const Symbol* signature, OverpassLookupMode overpass_mode) const { OverpassLookupMode overpass_local_mode = overpass_mode; const Klass* klass = this; while (klass != NULL) { Method* const method = InstanceKlass::cast(klass)->find_method_impl(name, signature, overpass_local_mode, find_static, find_private); if (method != NULL) { return method; } klass = klass->super(); overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses } return NULL; } #ifdef ASSERT // search through class hierarchy and return true if this class or // one of the superclasses was redefined bool InstanceKlass::has_redefined_this_or_super() const { const Klass* klass = this; while (klass != NULL) { if (InstanceKlass::cast(klass)->has_been_redefined()) { return true; } klass = klass->super(); } return false; } #endif // lookup a method in the default methods list then in all transitive interfaces // Do NOT return private or static methods Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, Symbol* signature) const { Method* m = NULL; if (default_methods() != NULL) { m = find_method(default_methods(), name, signature); } // Look up interfaces if (m == NULL) { m = lookup_method_in_all_interfaces(name, signature, find_defaults); } return m; } // lookup a method in all the interfaces that this class implements // Do NOT return private or static methods, new in JDK8 which are not externally visible // They should only be found in the initial InterfaceMethodRef Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, Symbol* signature, DefaultsLookupMode defaults_mode) const { Array* all_ifs = transitive_interfaces(); int num_ifs = all_ifs->length(); InstanceKlass *ik = NULL; for (int i = 0; i < num_ifs; i++) { ik = InstanceKlass::cast(all_ifs->at(i)); Method* m = ik->lookup_method(name, signature); if (m != NULL && m->is_public() && !m->is_static() && ((defaults_mode != skip_defaults) || !m->is_default_method())) { return m; } } return NULL; } /* jni_id_for_impl for jfieldIds only */ JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) { MutexLocker ml(JfieldIdCreation_lock); // Retry lookup after we got the lock JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset); if (probe == NULL) { // Slow case, allocate new static field identifier probe = new JNIid(this_k(), offset, this_k->jni_ids()); this_k->set_jni_ids(probe); } return probe; } /* jni_id_for for jfieldIds only */ JNIid* InstanceKlass::jni_id_for(int offset) { JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); if (probe == NULL) { probe = jni_id_for_impl(this, offset); } return probe; } u2 InstanceKlass::enclosing_method_data(int offset) const { const Array* const inner_class_list = inner_classes(); if (inner_class_list == NULL) { return 0; } const int length = inner_class_list->length(); if (length % inner_class_next_offset == 0) { return 0; } const int index = length - enclosing_method_attribute_size; assert(offset < enclosing_method_attribute_size, "invalid offset"); return inner_class_list->at(index + offset); } void InstanceKlass::set_enclosing_method_indices(u2 class_index, u2 method_index) { Array* inner_class_list = inner_classes(); assert (inner_class_list != NULL, "_inner_classes list is not set up"); int length = inner_class_list->length(); if (length % inner_class_next_offset == enclosing_method_attribute_size) { int index = length - enclosing_method_attribute_size; inner_class_list->at_put( index + enclosing_method_class_index_offset, class_index); inner_class_list->at_put( index + enclosing_method_method_index_offset, method_index); } } // Lookup or create a jmethodID. // This code is called by the VMThread and JavaThreads so the // locking has to be done very carefully to avoid deadlocks // and/or other cache consistency problems. // jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, const methodHandle& method_h) { size_t idnum = (size_t)method_h->method_idnum(); jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire(); size_t length = 0; jmethodID id = NULL; // We use a double-check locking idiom here because this cache is // performance sensitive. In the normal system, this cache only // transitions from NULL to non-NULL which is safe because we use // release_set_methods_jmethod_ids() to advertise the new cache. // A partially constructed cache should never be seen by a racing // thread. We also use release_store_ptr() to save a new jmethodID // in the cache so a partially constructed jmethodID should never be // seen either. Cache reads of existing jmethodIDs proceed without a // lock, but cache writes of a new jmethodID requires uniqueness and // creation of the cache itself requires no leaks so a lock is // generally acquired in those two cases. // // If the RedefineClasses() API has been used, then this cache can // grow and we'll have transitions from non-NULL to bigger non-NULL. // Cache creation requires no leaks and we require safety between all // cache accesses and freeing of the old cache so a lock is generally // acquired when the RedefineClasses() API has been used. if (jmeths != NULL) { // the cache already exists if (!ik_h->idnum_can_increment()) { // the cache can't grow so we can just get the current values get_jmethod_id_length_value(jmeths, idnum, &length, &id); } else { // cache can grow so we have to be more careful if (Threads::number_of_threads() == 0 || SafepointSynchronize::is_at_safepoint()) { // we're single threaded or at a safepoint - no locking needed get_jmethod_id_length_value(jmeths, idnum, &length, &id); } else { MutexLocker ml(JmethodIdCreation_lock); get_jmethod_id_length_value(jmeths, idnum, &length, &id); } } } // implied else: // we need to allocate a cache so default length and id values are good if (jmeths == NULL || // no cache yet length <= idnum || // cache is too short id == NULL) { // cache doesn't contain entry // This function can be called by the VMThread so we have to do all // things that might block on a safepoint before grabbing the lock. // Otherwise, we can deadlock with the VMThread or have a cache // consistency issue. These vars keep track of what we might have // to free after the lock is dropped. jmethodID to_dealloc_id = NULL; jmethodID* to_dealloc_jmeths = NULL; // may not allocate new_jmeths or use it if we allocate it jmethodID* new_jmeths = NULL; if (length <= idnum) { // allocate a new cache that might be used size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count()); new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass); memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); // cache size is stored in element[0], other elements offset by one new_jmeths[0] = (jmethodID)size; } // allocate a new jmethodID that might be used jmethodID new_id = NULL; if (method_h->is_old() && !method_h->is_obsolete()) { // The method passed in is old (but not obsolete), we need to use the current version Method* current_method = ik_h->method_with_idnum((int)idnum); assert(current_method != NULL, "old and but not obsolete, so should exist"); new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method); } else { // It is the current version of the method or an obsolete method, // use the version passed in new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h()); } if (Threads::number_of_threads() == 0 || SafepointSynchronize::is_at_safepoint()) { // we're single threaded or at a safepoint - no locking needed id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths, &to_dealloc_id, &to_dealloc_jmeths); } else { MutexLocker ml(JmethodIdCreation_lock); id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths, &to_dealloc_id, &to_dealloc_jmeths); } // The lock has been dropped so we can free resources. // Free up either the old cache or the new cache if we allocated one. if (to_dealloc_jmeths != NULL) { FreeHeap(to_dealloc_jmeths); } // free up the new ID since it wasn't needed if (to_dealloc_id != NULL) { Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id); } } return id; } // Figure out how many jmethodIDs haven't been allocated, and make // sure space for them is pre-allocated. This makes getting all // method ids much, much faster with classes with more than 8 // methods, and has a *substantial* effect on performance with jvmti // code that loads all jmethodIDs for all classes. void InstanceKlass::ensure_space_for_methodids(int start_offset) { int new_jmeths = 0; int length = methods()->length(); for (int index = start_offset; index < length; index++) { Method* m = methods()->at(index); jmethodID id = m->find_jmethod_id_or_null(); if (id == NULL) { new_jmeths++; } } if (new_jmeths != 0) { Method::ensure_jmethod_ids(class_loader_data(), new_jmeths); } } // Common code to fetch the jmethodID from the cache or update the // cache with the new jmethodID. This function should never do anything // that causes the caller to go to a safepoint or we can deadlock with // the VMThread or have cache consistency issues. // jmethodID InstanceKlass::get_jmethod_id_fetch_or_update( instanceKlassHandle ik_h, size_t idnum, jmethodID new_id, jmethodID* new_jmeths, jmethodID* to_dealloc_id_p, jmethodID** to_dealloc_jmeths_p) { assert(new_id != NULL, "sanity check"); assert(to_dealloc_id_p != NULL, "sanity check"); assert(to_dealloc_jmeths_p != NULL, "sanity check"); assert(Threads::number_of_threads() == 0 || SafepointSynchronize::is_at_safepoint() || JmethodIdCreation_lock->owned_by_self(), "sanity check"); // reacquire the cache - we are locked, single threaded or at a safepoint jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire(); jmethodID id = NULL; size_t length = 0; if (jmeths == NULL || // no cache yet (length = (size_t)jmeths[0]) <= idnum) { // cache is too short if (jmeths != NULL) { // copy any existing entries from the old cache for (size_t index = 0; index < length; index++) { new_jmeths[index+1] = jmeths[index+1]; } *to_dealloc_jmeths_p = jmeths; // save old cache for later delete } ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths); } else { // fetch jmethodID (if any) from the existing cache id = jmeths[idnum+1]; *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete } if (id == NULL) { // No matching jmethodID in the existing cache or we have a new // cache or we just grew the cache. This cache write is done here // by the first thread to win the foot race because a jmethodID // needs to be unique once it is generally available. id = new_id; // The jmethodID cache can be read while unlocked so we have to // make sure the new jmethodID is complete before installing it // in the cache. OrderAccess::release_store_ptr(&jmeths[idnum+1], id); } else { *to_dealloc_id_p = new_id; // save new id for later delete } return id; } // Common code to get the jmethodID cache length and the jmethodID // value at index idnum if there is one. // void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache, size_t idnum, size_t *length_p, jmethodID* id_p) { assert(cache != NULL, "sanity check"); assert(length_p != NULL, "sanity check"); assert(id_p != NULL, "sanity check"); // cache size is stored in element[0], other elements offset by one *length_p = (size_t)cache[0]; if (*length_p <= idnum) { // cache is too short *id_p = NULL; } else { *id_p = cache[idnum+1]; // fetch jmethodID (if any) } } // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { size_t idnum = (size_t)method->method_idnum(); jmethodID* jmeths = methods_jmethod_ids_acquire(); size_t length; // length assigned as debugging crumb jmethodID id = NULL; if (jmeths != NULL && // If there is a cache (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, id = jmeths[idnum+1]; // Look up the id (may be NULL) } return id; } inline DependencyContext InstanceKlass::dependencies() { DependencyContext dep_context(&_dep_context); return dep_context; } int InstanceKlass::mark_dependent_nmethods(DepChange& changes) { return dependencies().mark_dependent_nmethods(changes); } void InstanceKlass::add_dependent_nmethod(nmethod* nm) { dependencies().add_dependent_nmethod(nm); } void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) { dependencies().remove_dependent_nmethod(nm, delete_immediately); } #ifndef PRODUCT void InstanceKlass::print_dependent_nmethods(bool verbose) { dependencies().print_dependent_nmethods(verbose); } bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { return dependencies().is_dependent_nmethod(nm); } #endif //PRODUCT void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) { clean_implementors_list(is_alive); clean_method_data(is_alive); // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here. DependencyContext dep_context(&_dep_context); dep_context.expunge_stale_entries(); } void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) { assert(class_loader_data()->is_alive(is_alive), "this klass should be live"); if (is_interface()) { if (ClassUnloading) { Klass* impl = implementor(); if (impl != NULL) { if (!impl->is_loader_alive(is_alive)) { // remove this guy Klass** klass = adr_implementor(); assert(klass != NULL, "null klass"); if (klass != NULL) { *klass = NULL; } } } } } } void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) { for (int m = 0; m < methods()->length(); m++) { MethodData* mdo = methods()->at(m)->method_data(); if (mdo != NULL) { mdo->clean_method_data(is_alive); } } } static void remove_unshareable_in_class(Klass* k) { // remove klass's unshareable info k->remove_unshareable_info(); } void InstanceKlass::remove_unshareable_info() { Klass::remove_unshareable_info(); // Unlink the class if (is_linked()) { unlink_class(); } init_implementor(); constants()->remove_unshareable_info(); assert(_dep_context == DependencyContext::EMPTY, "dependency context is not shareable"); for (int i = 0; i < methods()->length(); i++) { Method* m = methods()->at(i); m->remove_unshareable_info(); } // do array classes also. array_klasses_do(remove_unshareable_in_class); } static void restore_unshareable_in_class(Klass* k, TRAPS) { // Array classes have null protection domain. // --> see ArrayKlass::complete_create_array_klass() k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK); } void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) { Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); instanceKlassHandle ik(THREAD, this); Array* methods = ik->methods(); int num_methods = methods->length(); for (int index2 = 0; index2 < num_methods; ++index2) { methodHandle m(THREAD, methods->at(index2)); m->restore_unshareable_info(CHECK); } if (JvmtiExport::has_redefined_a_class()) { // Reinitialize vtable because RedefineClasses may have changed some // entries in this vtable for super classes so the CDS vtable might // point to old or obsolete entries. RedefineClasses doesn't fix up // vtables in the shared system dictionary, only the main one. // It also redefines the itable too so fix that too. ResourceMark rm(THREAD); ik->vtable()->initialize_vtable(false, CHECK); ik->itable()->initialize_itable(false, CHECK); } // restore constant pool resolved references ik->constants()->restore_unshareable_info(CHECK); ik->array_klasses_do(restore_unshareable_in_class, CHECK); } // returns true IFF is_in_error_state() has been changed as a result of this call. bool InstanceKlass::check_sharing_error_state() { assert(DumpSharedSpaces, "should only be called during dumping"); bool old_state = is_in_error_state(); if (!is_in_error_state()) { bool bad = false; for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) { if (sup->is_in_error_state()) { bad = true; break; } } if (!bad) { Array* interfaces = transitive_interfaces(); for (int i = 0; i < interfaces->length(); i++) { Klass* iface = interfaces->at(i); if (InstanceKlass::cast(iface)->is_in_error_state()) { bad = true; break; } } } if (bad) { set_in_error_state(); } } return (old_state != is_in_error_state()); } static void clear_all_breakpoints(Method* m) { m->clear_all_breakpoints(); } void InstanceKlass::notify_unload_class(InstanceKlass* ik) { // notify the debugger if (JvmtiExport::should_post_class_unload()) { JvmtiExport::post_class_unload(ik); } // notify ClassLoadingService of class unload ClassLoadingService::notify_class_unloaded(ik); } void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) { // Clean up C heap ik->release_C_heap_structures(); ik->constants()->release_C_heap_structures(); } void InstanceKlass::release_C_heap_structures() { // Can't release the constant pool here because the constant pool can be // deallocated separately from the InstanceKlass for default methods and // redefine classes. // Deallocate oop map cache if (_oop_map_cache != NULL) { delete _oop_map_cache; _oop_map_cache = NULL; } // Deallocate JNI identifiers for jfieldIDs JNIid::deallocate(jni_ids()); set_jni_ids(NULL); jmethodID* jmeths = methods_jmethod_ids_acquire(); if (jmeths != (jmethodID*)NULL) { release_set_methods_jmethod_ids(NULL); FreeHeap(jmeths); } // Deallocate MemberNameTable { Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock; MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag); MemberNameTable* mnt = member_names(); if (mnt != NULL) { delete mnt; set_member_names(NULL); } } // Release dependencies. // It is desirable to use DC::remove_all_dependents() here, but, unfortunately, // it is not safe (see JDK-8143408). The problem is that the klass dependency // context can contain live dependencies, since there's a race between nmethod & // klass unloading. If the klass is dead when nmethod unloading happens, relevant // dependencies aren't removed from the context associated with the class (see // nmethod::flush_dependencies). It ends up during klass unloading as seemingly // live dependencies pointing to unloaded nmethods and causes a crash in // DC::remove_all_dependents() when it touches unloaded nmethod. dependencies().wipe(); // Deallocate breakpoint records if (breakpoints() != 0x0) { methods_do(clear_all_breakpoints); assert(breakpoints() == 0x0, "should have cleared breakpoints"); } // deallocate the cached class file if (_cached_class_file != NULL) { os::free(_cached_class_file); _cached_class_file = NULL; } // Decrement symbol reference counts associated with the unloaded class. if (_name != NULL) _name->decrement_refcount(); // unreference array name derived from this class name (arrays of an unloaded // class can't be referenced anymore). if (_array_name != NULL) _array_name->decrement_refcount(); if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension); assert(_total_instanceKlass_count >= 1, "Sanity check"); Atomic::dec(&_total_instanceKlass_count); } void InstanceKlass::set_source_debug_extension(const char* array, int length) { if (array == NULL) { _source_debug_extension = NULL; } else { // Adding one to the attribute length in order to store a null terminator // character could cause an overflow because the attribute length is // already coded with an u4 in the classfile, but in practice, it's // unlikely to happen. assert((length+1) > length, "Overflow checking"); char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); for (int i = 0; i < length; i++) { sde[i] = array[i]; } sde[length] = '\0'; _source_debug_extension = sde; } } address InstanceKlass::static_field_addr(int offset) { return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop(java_mirror())); } const char* InstanceKlass::signature_name() const { int hash_len = 0; char hash_buf[40]; // If this is an anonymous class, append a hash to make the name unique if (is_anonymous()) { intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0; jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash); hash_len = (int)strlen(hash_buf); } // Get the internal name as a c string const char* src = (const char*) (name()->as_C_string()); const int src_length = (int)strlen(src); char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3); // Add L as type indicator int dest_index = 0; dest[dest_index++] = 'L'; // Add the actual class name for (int src_index = 0; src_index < src_length; ) { dest[dest_index++] = src[src_index++]; } // If we have a hash, append it for (int hash_index = 0; hash_index < hash_len; ) { dest[dest_index++] = hash_buf[hash_index++]; } // Add the semicolon and the NULL dest[dest_index++] = ';'; dest[dest_index] = '\0'; return dest; } // different verisons of is_same_class_package bool InstanceKlass::is_same_class_package(const Klass* class2) const { const Klass* const class1 = (const Klass* const)this; oop classloader1 = InstanceKlass::cast(class1)->class_loader(); const Symbol* const classname1 = class1->name(); if (class2->is_objArray_klass()) { class2 = ObjArrayKlass::cast(class2)->bottom_klass(); } oop classloader2; if (class2->is_instance_klass()) { classloader2 = InstanceKlass::cast(class2)->class_loader(); } else { assert(class2->is_typeArray_klass(), "should be type array"); classloader2 = NULL; } const Symbol* classname2 = class2->name(); return InstanceKlass::is_same_class_package(classloader1, classname1, classloader2, classname2); } bool InstanceKlass::is_same_class_package(oop other_class_loader, const Symbol* other_class_name) const { oop this_class_loader = class_loader(); const Symbol* const this_class_name = name(); return InstanceKlass::is_same_class_package(this_class_loader, this_class_name, other_class_loader, other_class_name); } // return true if two classes are in the same package, classloader // and classname information is enough to determine a class's package bool InstanceKlass::is_same_class_package(oop class_loader1, const Symbol* class_name1, oop class_loader2, const Symbol* class_name2) { if (class_loader1 != class_loader2) { return false; } else if (class_name1 == class_name2) { return true; // skip painful bytewise comparison } else { ResourceMark rm; // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding. // Otherwise, we just compare jbyte values between the strings. const jbyte *name1 = class_name1->base(); const jbyte *name2 = class_name2->base(); const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/'); const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/'); if ((last_slash1 == NULL) || (last_slash2 == NULL)) { // One of the two doesn't have a package. Only return true // if the other one also doesn't have a package. return last_slash1 == last_slash2; } else { // Skip over '['s if (*name1 == '[') { do { name1++; } while (*name1 == '['); if (*name1 != 'L') { // Something is terribly wrong. Shouldn't be here. return false; } } if (*name2 == '[') { do { name2++; } while (*name2 == '['); if (*name2 != 'L') { // Something is terribly wrong. Shouldn't be here. return false; } } // Check that package part is identical int length1 = last_slash1 - name1; int length2 = last_slash2 - name2; return UTF8::equal(name1, length1, name2, length2); } } } // Returns true iff super_method can be overridden by a method in targetclassname // See JSL 3rd edition 8.4.6.1 // Assumes name-signature match // "this" is InstanceKlass of super_method which must exist // note that the InstanceKlass of the method in the targetclassname has not always been created yet bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) { // Private methods can not be overridden if (super_method->is_private()) { return false; } // If super method is accessible, then override if ((super_method->is_protected()) || (super_method->is_public())) { return true; } // Package-private methods are not inherited outside of package assert(super_method->is_package_private(), "must be package private"); return(is_same_class_package(targetclassloader(), targetclassname)); } /* defined for now in jvm.cpp, for historical reasons *-- Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self, Symbol*& simple_name_result, TRAPS) { ... } */ // tell if two classes have the same enclosing class (at package level) bool InstanceKlass::is_same_package_member_impl(const InstanceKlass* class1, const Klass* class2, TRAPS) { if (class2 == class1) return true; if (!class2->is_instance_klass()) return false; // must be in same package before we try anything else if (!class1->is_same_class_package(class2->class_loader(), class2->name())) return false; // As long as there is an outer1.getEnclosingClass, // shift the search outward. const InstanceKlass* outer1 = class1; for (;;) { // As we walk along, look for equalities between outer1 and class2. // Eventually, the walks will terminate as outer1 stops // at the top-level class around the original class. bool ignore_inner_is_member; const Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member, CHECK_false); if (next == NULL) break; if (next == class2) return true; outer1 = InstanceKlass::cast(next); } // Now do the same for class2. const InstanceKlass* outer2 = InstanceKlass::cast(class2); for (;;) { bool ignore_inner_is_member; Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member, CHECK_false); if (next == NULL) break; // Might as well check the new outer against all available values. if (next == class1) return true; if (next == outer1) return true; outer2 = InstanceKlass::cast(next); } // If by this point we have not found an equality between the // two classes, we know they are in separate package members. return false; } bool InstanceKlass::find_inner_classes_attr(instanceKlassHandle k, int* ooff, int* noff, TRAPS) { constantPoolHandle i_cp(THREAD, k->constants()); for (InnerClassesIterator iter(k); !iter.done(); iter.next()) { int ioff = iter.inner_class_info_index(); if (ioff != 0) { // Check to see if the name matches the class we're looking for // before attempting to find the class. if (i_cp->klass_name_at_matches(k, ioff)) { Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); if (k() == inner_klass) { *ooff = iter.outer_class_info_index(); *noff = iter.inner_name_index(); return true; } } } } return false; } InstanceKlass* InstanceKlass::compute_enclosing_class_impl(const InstanceKlass* k, bool* inner_is_member, TRAPS) { InstanceKlass* outer_klass = NULL; *inner_is_member = false; int ooff = 0, noff = 0; if (find_inner_classes_attr(k, &ooff, &noff, THREAD)) { constantPoolHandle i_cp(THREAD, k->constants()); if (ooff != 0) { Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); outer_klass = InstanceKlass::cast(ok); *inner_is_member = true; } if (NULL == outer_klass) { // It may be anonymous; try for that. int encl_method_class_idx = k->enclosing_method_class_index(); if (encl_method_class_idx != 0) { Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); outer_klass = InstanceKlass::cast(ok); *inner_is_member = false; } } } // If no inner class attribute found for this class. if (NULL == outer_klass) return NULL; // Throws an exception if outer klass has not declared k as an inner klass // We need evidence that each klass knows about the other, or else // the system could allow a spoof of an inner class to gain access rights. Reflection::check_for_inner_class(outer_klass, k, *inner_is_member, CHECK_NULL); return outer_klass; } jint InstanceKlass::compute_modifier_flags(TRAPS) const { jint access = access_flags().as_int(); // But check if it happens to be member class. instanceKlassHandle ik(THREAD, this); InnerClassesIterator iter(ik); for (; !iter.done(); iter.next()) { int ioff = iter.inner_class_info_index(); // Inner class attribute can be zero, skip it. // Strange but true: JVM spec. allows null inner class refs. if (ioff == 0) continue; // only look at classes that are already loaded // since we are looking for the flags for our self. Symbol* inner_name = ik->constants()->klass_name_at(ioff); if ((ik->name() == inner_name)) { // This is really a member class. access = iter.inner_access_flags(); break; } } // Remember to strip ACC_SUPER bit return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS; } jint InstanceKlass::jvmti_class_status() const { jint result = 0; if (is_linked()) { result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; } if (is_initialized()) { assert(is_linked(), "Class status is not consistent"); result |= JVMTI_CLASS_STATUS_INITIALIZED; } if (is_in_error_state()) { result |= JVMTI_CLASS_STATUS_ERROR; } return result; } Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) { itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); int method_table_offset_in_words = ioe->offset()/wordSize; int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) / itableOffsetEntry::size(); for (int cnt = 0 ; ; cnt ++, ioe ++) { // If the interface isn't implemented by the receiver class, // the VM should throw IncompatibleClassChangeError. if (cnt >= nof_interfaces) { THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError()); } Klass* ik = ioe->interface_klass(); if (ik == holder) break; } itableMethodEntry* ime = ioe->first_method_entry(this); Method* m = ime[index].method(); if (m == NULL) { THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); } return m; } #if INCLUDE_JVMTI // update default_methods for redefineclasses for methods that are // not yet in the vtable due to concurrent subclass define and superinterface // redefinition // Note: those in the vtable, should have been updated via adjust_method_entries void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) { // search the default_methods for uses of either obsolete or EMCP methods if (default_methods() != NULL) { for (int index = 0; index < default_methods()->length(); index ++) { Method* old_method = default_methods()->at(index); if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) { continue; // skip uninteresting entries } assert(!old_method->is_deleted(), "default methods may not be deleted"); Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum()); assert(new_method != NULL, "method_with_idnum() should not be NULL"); assert(old_method != new_method, "sanity check"); default_methods()->at_put(index, new_method); if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) { if (!(*trace_name_printed)) { // RC_TRACE_MESG macro has an embedded ResourceMark RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s", external_name(), old_method->method_holder()->external_name())); *trace_name_printed = true; } RC_TRACE(0x00100000, ("default method update: %s(%s) ", new_method->name()->as_C_string(), new_method->signature()->as_C_string())); } } } } #endif // INCLUDE_JVMTI // On-stack replacement stuff void InstanceKlass::add_osr_nmethod(nmethod* n) { // only one compilation can be active { // This is a short non-blocking critical region, so the no safepoint check is ok. MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); assert(n->is_osr_method(), "wrong kind of nmethod"); n->set_osr_link(osr_nmethods_head()); set_osr_nmethods_head(n); // Raise the highest osr level if necessary if (TieredCompilation) { Method* m = n->method(); m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level())); } } // Get rid of the osr methods for the same bci that have lower levels. if (TieredCompilation) { for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); if (inv != NULL && inv->is_in_use()) { inv->make_not_entrant(); } } } } void InstanceKlass::remove_osr_nmethod(nmethod* n) { // This is a short non-blocking critical region, so the no safepoint check is ok. MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); assert(n->is_osr_method(), "wrong kind of nmethod"); nmethod* last = NULL; nmethod* cur = osr_nmethods_head(); int max_level = CompLevel_none; // Find the max comp level excluding n Method* m = n->method(); // Search for match while(cur != NULL && cur != n) { if (TieredCompilation && m == cur->method()) { // Find max level before n max_level = MAX2(max_level, cur->comp_level()); } last = cur; cur = cur->osr_link(); } nmethod* next = NULL; if (cur == n) { next = cur->osr_link(); if (last == NULL) { // Remove first element set_osr_nmethods_head(next); } else { last->set_osr_link(next); } } n->set_osr_link(NULL); if (TieredCompilation) { cur = next; while (cur != NULL) { // Find max level after n if (m == cur->method()) { max_level = MAX2(max_level, cur->comp_level()); } cur = cur->osr_link(); } m->set_highest_osr_comp_level(max_level); } } int InstanceKlass::mark_osr_nmethods(const Method* m) { // This is a short non-blocking critical region, so the no safepoint check is ok. MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); nmethod* osr = osr_nmethods_head(); int found = 0; while (osr != NULL) { assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); if (osr->method() == m) { osr->mark_for_deoptimization(); found++; } osr = osr->osr_link(); } return found; } nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { // This is a short non-blocking critical region, so the no safepoint check is ok. MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); nmethod* osr = osr_nmethods_head(); nmethod* best = NULL; while (osr != NULL) { assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); // There can be a time when a c1 osr method exists but we are waiting // for a c2 version. When c2 completes its osr nmethod we will trash // the c1 version and only be able to find the c2 version. However // while we overflow in the c1 code at back branches we don't want to // try and switch to the same code as we are already running if (osr->method() == m && (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { if (match_level) { if (osr->comp_level() == comp_level) { // Found a match - return it. return osr; } } else { if (best == NULL || (osr->comp_level() > best->comp_level())) { if (osr->comp_level() == CompLevel_highest_tier) { // Found the best possible - return it. return osr; } best = osr; } } } osr = osr->osr_link(); } if (best != NULL && best->comp_level() >= comp_level && match_level == false) { return best; } return NULL; } bool InstanceKlass::add_member_name(Handle mem_name) { jweak mem_name_wref = JNIHandles::make_weak_global(mem_name); MutexLocker ml(MemberNameTable_lock); DEBUG_ONLY(NoSafepointVerifier nsv); // Check if method has been redefined while taking out MemberNameTable_lock, if so // return false. We cannot cache obsolete methods. They will crash when the function // is called! Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name()); if (method->is_obsolete()) { return false; } else if (method->is_old()) { // Replace method with redefined version java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum())); } if (_member_names == NULL) { _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count()); } _member_names->add_member_name(mem_name_wref); return true; } // ----------------------------------------------------------------------------------------------------- // Printing #ifndef PRODUCT #define BULLET " - " static const char* state_names[] = { "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" }; static void print_vtable(intptr_t* start, int len, outputStream* st) { for (int i = 0; i < len; i++) { intptr_t e = start[i]; st->print("%d : " INTPTR_FORMAT, i, e); if (e != 0 && ((Metadata*)e)->is_metaspace_object()) { st->print(" "); ((Metadata*)e)->print_value_on(st); } st->cr(); } } void InstanceKlass::print_on(outputStream* st) const { assert(is_klass(), "must be klass"); Klass::print_on(st); st->print(BULLET"instance size: %d", size_helper()); st->cr(); st->print(BULLET"klass size: %d", size()); st->cr(); st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]); st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr(); st->print(BULLET"sub: "); Klass* sub = subklass(); int n; for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) { if (n < MaxSubklassPrintSize) { sub->print_value_on(st); st->print(" "); } } if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize); st->cr(); if (is_interface()) { st->print_cr(BULLET"nof implementors: %d", nof_implementors()); if (nof_implementors() == 1) { st->print_cr(BULLET"implementor: "); st->print(" "); implementor()->print_value_on(st); st->cr(); } } st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr(); st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr(); if (Verbose || WizardMode) { Array* method_array = methods(); for (int i = 0; i < method_array->length(); i++) { st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); } } st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr(); st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr(); if (Verbose && default_methods() != NULL) { Array* method_array = default_methods(); for (int i = 0; i < method_array->length(); i++) { st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); } } if (default_vtable_indices() != NULL) { st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr(); } st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); if (class_loader_data() != NULL) { st->print(BULLET"class loader data: "); class_loader_data()->print_value_on(st); st->cr(); } st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr(); if (source_file_name() != NULL) { st->print(BULLET"source file: "); source_file_name()->print_value_on(st); st->cr(); } if (source_debug_extension() != NULL) { st->print(BULLET"source debug extension: "); st->print("%s", source_debug_extension()); st->cr(); } st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr(); st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr(); st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr(); st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr(); { bool have_pv = false; // previous versions are linked together through the InstanceKlass for (InstanceKlass* pv_node = _previous_versions; pv_node != NULL; pv_node = pv_node->previous_versions()) { if (!have_pv) st->print(BULLET"previous version: "); have_pv = true; pv_node->constants()->print_value_on(st); } if (have_pv) st->cr(); } if (generic_signature() != NULL) { st->print(BULLET"generic signature: "); generic_signature()->print_value_on(st); st->cr(); } st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr(); st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st); st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); FieldPrinter print_static_field(st); ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); FieldPrinter print_nonstatic_field(st); InstanceKlass* ik = const_cast(this); ik->do_nonstatic_fields(&print_nonstatic_field); st->print(BULLET"non-static oop maps: "); OopMapBlock* map = start_of_nonstatic_oop_maps(); OopMapBlock* end_map = map + nonstatic_oop_map_count(); while (map < end_map) { st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); map++; } st->cr(); } #endif //PRODUCT void InstanceKlass::print_value_on(outputStream* st) const { assert(is_klass(), "must be klass"); if (Verbose || WizardMode) access_flags().print_on(st); name()->print_value_on(st); } #ifndef PRODUCT void FieldPrinter::do_field(fieldDescriptor* fd) { _st->print(BULLET); if (_obj == NULL) { fd->print_on(_st); _st->cr(); } else { fd->print_on_for(_st, _obj); _st->cr(); } } void InstanceKlass::oop_print_on(oop obj, outputStream* st) { Klass::oop_print_on(obj, st); if (this == SystemDictionary::String_klass()) { typeArrayOop value = java_lang_String::value(obj); juint length = java_lang_String::length(obj); if (value != NULL && value->is_typeArray() && length <= (juint) value->length()) { st->print(BULLET"string: "); java_lang_String::print(obj, st); st->cr(); if (!WizardMode) return; // that is enough } } st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj)); FieldPrinter print_field(st, obj); do_nonstatic_fields(&print_field); if (this == SystemDictionary::Class_klass()) { st->print(BULLET"signature: "); java_lang_Class::print_signature(obj, st); st->cr(); Klass* mirrored_klass = java_lang_Class::as_Klass(obj); st->print(BULLET"fake entry for mirror: "); mirrored_klass->print_value_on_maybe_null(st); st->cr(); Klass* array_klass = java_lang_Class::array_klass(obj); st->print(BULLET"fake entry for array: "); array_klass->print_value_on_maybe_null(st); st->cr(); st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj)); st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj)); Klass* real_klass = java_lang_Class::as_Klass(obj); if (real_klass != NULL && real_klass->is_instance_klass()) { InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); } } else if (this == SystemDictionary::MethodType_klass()) { st->print(BULLET"signature: "); java_lang_invoke_MethodType::print_signature(obj, st); st->cr(); } } #endif //PRODUCT void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { st->print("a "); name()->print_value_on(st); obj->print_address_on(st); if (this == SystemDictionary::String_klass() && java_lang_String::value(obj) != NULL) { ResourceMark rm; int len = java_lang_String::length(obj); int plen = (len < 24 ? len : 12); char* str = java_lang_String::as_utf8_string(obj, 0, plen); st->print(" = \"%s\"", str); if (len > plen) st->print("...[%d]", len); } else if (this == SystemDictionary::Class_klass()) { Klass* k = java_lang_Class::as_Klass(obj); st->print(" = "); if (k != NULL) { k->print_value_on(st); } else { const char* tname = type2name(java_lang_Class::primitive_type(obj)); st->print("%s", tname ? tname : "type?"); } } else if (this == SystemDictionary::MethodType_klass()) { st->print(" = "); java_lang_invoke_MethodType::print_signature(obj, st); } else if (java_lang_boxing_object::is_instance(obj)) { st->print(" = "); java_lang_boxing_object::print(obj, st); } else if (this == SystemDictionary::LambdaForm_klass()) { oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); if (vmentry != NULL) { st->print(" => "); vmentry->print_value_on(st); } } else if (this == SystemDictionary::MemberName_klass()) { Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); if (vmtarget != NULL) { st->print(" = "); vmtarget->print_value_on(st); } else { java_lang_invoke_MemberName::clazz(obj)->print_value_on(st); st->print("."); java_lang_invoke_MemberName::name(obj)->print_value_on(st); } } } const char* InstanceKlass::internal_name() const { return external_name(); } #if INCLUDE_SERVICES // Size Statistics void InstanceKlass::collect_statistics(KlassSizeStats *sz) const { Klass::collect_statistics(sz); sz->_inst_size = HeapWordSize * size_helper(); sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length()); sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length()); sz->_nonstatic_oopmap_bytes = HeapWordSize * ((is_interface() || is_anonymous()) ? align_object_offset(nonstatic_oop_map_size()) : nonstatic_oop_map_size()); int n = 0; n += (sz->_methods_array_bytes = sz->count_array(methods())); n += (sz->_method_ordering_bytes = sz->count_array(method_ordering())); n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces())); n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces())); n += (sz->_fields_bytes = sz->count_array(fields())); n += (sz->_inner_classes_bytes = sz->count_array(inner_classes())); sz->_ro_bytes += n; const ConstantPool* cp = constants(); if (cp) { cp->collect_statistics(sz); } const Annotations* anno = annotations(); if (anno) { anno->collect_statistics(sz); } const Array* methods_array = methods(); if (methods()) { for (int i = 0; i < methods_array->length(); i++) { Method* method = methods_array->at(i); if (method) { sz->_method_count ++; method->collect_statistics(sz); } } } } #endif // INCLUDE_SERVICES // Verification class VerifyFieldClosure: public OopClosure { protected: template void do_oop_work(T* p) { oop obj = oopDesc::load_decode_heap_oop(p); if (!obj->is_oop_or_null()) { tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); Universe::print_on(tty); guarantee(false, "boom"); } } public: virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } }; void InstanceKlass::verify_on(outputStream* st) { #ifndef PRODUCT // Avoid redundant verifies, this really should be in product. if (_verify_count == Universe::verify_count()) return; _verify_count = Universe::verify_count(); #endif // Verify Klass Klass::verify_on(st); // Verify that klass is present in ClassLoaderData guarantee(class_loader_data()->contains_klass(this), "this class isn't found in class loader data"); // Verify vtables if (is_linked()) { ResourceMark rm; // $$$ This used to be done only for m/s collections. Doing it // always seemed a valid generalization. (DLD -- 6/00) vtable()->verify(st); } // Verify first subklass if (subklass() != NULL) { guarantee(subklass()->is_klass(), "should be klass"); } // Verify siblings Klass* super = this->super(); Klass* sib = next_sibling(); if (sib != NULL) { if (sib == this) { fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); } guarantee(sib->is_klass(), "should be klass"); guarantee(sib->super() == super, "siblings should have same superklass"); } // Verify implementor fields Klass* im = implementor(); if (im != NULL) { guarantee(is_interface(), "only interfaces should have implementor set"); guarantee(im->is_klass(), "should be klass"); guarantee(!im->is_interface() || im == this, "implementors cannot be interfaces"); } // Verify local interfaces if (local_interfaces()) { Array* local_interfaces = this->local_interfaces(); for (int j = 0; j < local_interfaces->length(); j++) { Klass* e = local_interfaces->at(j); guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); } } // Verify transitive interfaces if (transitive_interfaces() != NULL) { Array* transitive_interfaces = this->transitive_interfaces(); for (int j = 0; j < transitive_interfaces->length(); j++) { Klass* e = transitive_interfaces->at(j); guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); } } // Verify methods if (methods() != NULL) { Array* methods = this->methods(); for (int j = 0; j < methods->length(); j++) { guarantee(methods->at(j)->is_method(), "non-method in methods array"); } for (int j = 0; j < methods->length() - 1; j++) { Method* m1 = methods->at(j); Method* m2 = methods->at(j + 1); guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); } } // Verify method ordering if (method_ordering() != NULL) { Array* method_ordering = this->method_ordering(); int length = method_ordering->length(); if (JvmtiExport::can_maintain_original_method_order() || ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) { guarantee(length == methods()->length(), "invalid method ordering length"); jlong sum = 0; for (int j = 0; j < length; j++) { int original_index = method_ordering->at(j); guarantee(original_index >= 0, "invalid method ordering index"); guarantee(original_index < length, "invalid method ordering index"); sum += original_index; } // Verify sum of indices 0,1,...,length-1 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); } else { guarantee(length == 0, "invalid method ordering length"); } } // Verify default methods if (default_methods() != NULL) { Array* methods = this->default_methods(); for (int j = 0; j < methods->length(); j++) { guarantee(methods->at(j)->is_method(), "non-method in methods array"); } for (int j = 0; j < methods->length() - 1; j++) { Method* m1 = methods->at(j); Method* m2 = methods->at(j + 1); guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); } } // Verify JNI static field identifiers if (jni_ids() != NULL) { jni_ids()->verify(this); } // Verify other fields if (array_klasses() != NULL) { guarantee(array_klasses()->is_klass(), "should be klass"); } if (constants() != NULL) { guarantee(constants()->is_constantPool(), "should be constant pool"); } const Klass* host = host_klass(); if (host != NULL) { guarantee(host->is_klass(), "should be klass"); } } void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { Klass::oop_verify_on(obj, st); VerifyFieldClosure blk; obj->oop_iterate_no_header(&blk); } // JNIid class for jfieldIDs only // Note to reviewers: // These JNI functions are just moved over to column 1 and not changed // in the compressed oops workspace. JNIid::JNIid(Klass* holder, int offset, JNIid* next) { _holder = holder; _offset = offset; _next = next; debug_only(_is_static_field_id = false;) } JNIid* JNIid::find(int offset) { JNIid* current = this; while (current != NULL) { if (current->offset() == offset) return current; current = current->next(); } return NULL; } void JNIid::deallocate(JNIid* current) { while (current != NULL) { JNIid* next = current->next(); delete current; current = next; } } void JNIid::verify(Klass* holder) { int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); int end_field_offset; end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); JNIid* current = this; while (current != NULL) { guarantee(current->holder() == holder, "Invalid klass in JNIid"); #ifdef ASSERT int o = current->offset(); if (current->is_static_field_id()) { guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); } #endif current = current->next(); } } #ifdef ASSERT void InstanceKlass::set_init_state(ClassState state) { bool good_state = is_shared() ? (_init_state <= state) : (_init_state < state); assert(good_state || state == allocated, "illegal state transition"); _init_state = (u1)state; } #endif // RedefineClasses() support for previous versions: int InstanceKlass::_previous_version_count = 0; // Purge previous versions before adding new previous versions of the class. void InstanceKlass::purge_previous_versions(InstanceKlass* ik) { if (ik->previous_versions() != NULL) { // This klass has previous versions so see what we can cleanup // while it is safe to do so. int deleted_count = 0; // leave debugging breadcrumbs int live_count = 0; ClassLoaderData* loader_data = ik->class_loader_data(); assert(loader_data != NULL, "should never be null"); // RC_TRACE macro has an embedded ResourceMark RC_TRACE(0x00000200, ("purge: %s: previous versions", ik->external_name())); // previous versions are linked together through the InstanceKlass InstanceKlass* pv_node = ik->previous_versions(); InstanceKlass* last = ik; int version = 0; // check the previous versions list for (; pv_node != NULL; ) { ConstantPool* pvcp = pv_node->constants(); assert(pvcp != NULL, "cp ref was unexpectedly cleared"); if (!pvcp->on_stack()) { // If the constant pool isn't on stack, none of the methods // are executing. Unlink this previous_version. // The previous version InstanceKlass is on the ClassLoaderData deallocate list // so will be deallocated during the next phase of class unloading. RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is dead", p2i(pv_node))); // For debugging purposes. pv_node->set_is_scratch_class(); pv_node->class_loader_data()->add_to_deallocate_list(pv_node); pv_node = pv_node->previous_versions(); last->link_previous_versions(pv_node); deleted_count++; version++; continue; } else { RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is alive", p2i(pv_node))); assert(pvcp->pool_holder() != NULL, "Constant pool with no holder"); guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); live_count++; } // At least one method is live in this previous version. // Reset dead EMCP methods not to get breakpoints. // All methods are deallocated when all of the methods for this class are no // longer running. Array* method_refs = pv_node->methods(); if (method_refs != NULL) { RC_TRACE(0x00000200, ("purge: previous methods length=%d", method_refs->length())); for (int j = 0; j < method_refs->length(); j++) { Method* method = method_refs->at(j); if (!method->on_stack()) { // no breakpoints for non-running methods if (method->is_running_emcp()) { method->set_running_emcp(false); } } else { assert (method->is_obsolete() || method->is_running_emcp(), "emcp method cannot run after emcp bit is cleared"); // RC_TRACE macro has an embedded ResourceMark RC_TRACE(0x00000200, ("purge: %s(%s): prev method @%d in version @%d is alive", method->name()->as_C_string(), method->signature()->as_C_string(), j, version)); } } } // next previous version last = pv_node; pv_node = pv_node->previous_versions(); version++; } RC_TRACE(0x00000200, ("purge: previous version stats: live=%d, deleted=%d", live_count, deleted_count)); } } void InstanceKlass::mark_newly_obsolete_methods(Array* old_methods, int emcp_method_count) { int obsolete_method_count = old_methods->length() - emcp_method_count; if (emcp_method_count != 0 && obsolete_method_count != 0 && _previous_versions != NULL) { // We have a mix of obsolete and EMCP methods so we have to // clear out any matching EMCP method entries the hard way. int local_count = 0; for (int i = 0; i < old_methods->length(); i++) { Method* old_method = old_methods->at(i); if (old_method->is_obsolete()) { // only obsolete methods are interesting Symbol* m_name = old_method->name(); Symbol* m_signature = old_method->signature(); // previous versions are linked together through the InstanceKlass int j = 0; for (InstanceKlass* prev_version = _previous_versions; prev_version != NULL; prev_version = prev_version->previous_versions(), j++) { Array* method_refs = prev_version->methods(); for (int k = 0; k < method_refs->length(); k++) { Method* method = method_refs->at(k); if (!method->is_obsolete() && method->name() == m_name && method->signature() == m_signature) { // The current RedefineClasses() call has made all EMCP // versions of this method obsolete so mark it as obsolete RC_TRACE(0x00000400, ("add: %s(%s): flush obsolete method @%d in version @%d", m_name->as_C_string(), m_signature->as_C_string(), k, j)); method->set_is_obsolete(); break; } } // The previous loop may not find a matching EMCP method, but // that doesn't mean that we can optimize and not go any // further back in the PreviousVersion generations. The EMCP // method for this generation could have already been made obsolete, // but there still may be an older EMCP method that has not // been made obsolete. } if (++local_count >= obsolete_method_count) { // no more obsolete methods so bail out now break; } } } } } // Save the scratch_class as the previous version if any of the methods are running. // The previous_versions are used to set breakpoints in EMCP methods and they are // also used to clean MethodData links to redefined methods that are no longer running. void InstanceKlass::add_previous_version(instanceKlassHandle scratch_class, int emcp_method_count) { assert(Thread::current()->is_VM_thread(), "only VMThread can add previous versions"); // RC_TRACE macro has an embedded ResourceMark RC_TRACE(0x00000400, ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count)); // Clean out old previous versions purge_previous_versions(this); // Mark newly obsolete methods in remaining previous versions. An EMCP method from // a previous redefinition may be made obsolete by this redefinition. Array* old_methods = scratch_class->methods(); mark_newly_obsolete_methods(old_methods, emcp_method_count); // If the constant pool for this previous version of the class // is not marked as being on the stack, then none of the methods // in this previous version of the class are on the stack so // we don't need to add this as a previous version. ConstantPool* cp_ref = scratch_class->constants(); if (!cp_ref->on_stack()) { RC_TRACE(0x00000400, ("add: scratch class not added; no methods are running")); // For debugging purposes. scratch_class->set_is_scratch_class(); scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class()); // Update count for class unloading. _previous_version_count--; return; } if (emcp_method_count != 0) { // At least one method is still running, check for EMCP methods for (int i = 0; i < old_methods->length(); i++) { Method* old_method = old_methods->at(i); if (!old_method->is_obsolete() && old_method->on_stack()) { // if EMCP method (not obsolete) is on the stack, mark as EMCP so that // we can add breakpoints for it. // We set the method->on_stack bit during safepoints for class redefinition // and use this bit to set the is_running_emcp bit. // After the safepoint, the on_stack bit is cleared and the running emcp // method may exit. If so, we would set a breakpoint in a method that // is never reached, but this won't be noticeable to the programmer. old_method->set_running_emcp(true); RC_TRACE(0x00000400, ("add: EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method))); } else if (!old_method->is_obsolete()) { RC_TRACE(0x00000400, ("add: EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method))); } } } // Add previous version if any methods are still running. RC_TRACE(0x00000400, ("add: scratch class added; one of its methods is on_stack")); assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version"); scratch_class->link_previous_versions(previous_versions()); link_previous_versions(scratch_class()); // Update count for class unloading. _previous_version_count++; } // end add_previous_version() Method* InstanceKlass::method_with_idnum(int idnum) { Method* m = NULL; if (idnum < methods()->length()) { m = methods()->at(idnum); } if (m == NULL || m->method_idnum() != idnum) { for (int index = 0; index < methods()->length(); ++index) { m = methods()->at(index); if (m->method_idnum() == idnum) { return m; } } // None found, return null for the caller to handle. return NULL; } return m; } Method* InstanceKlass::method_with_orig_idnum(int idnum) { if (idnum >= methods()->length()) { return NULL; } Method* m = methods()->at(idnum); if (m != NULL && m->orig_method_idnum() == idnum) { return m; } // Obsolete method idnum does not match the original idnum for (int index = 0; index < methods()->length(); ++index) { m = methods()->at(index); if (m->orig_method_idnum() == idnum) { return m; } } // None found, return null for the caller to handle. return NULL; } Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) { InstanceKlass* holder = get_klass_version(version); if (holder == NULL) { return NULL; // The version of klass is gone, no method is found } Method* method = holder->method_with_orig_idnum(idnum); return method; } jint InstanceKlass::get_cached_class_file_len() { return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); } unsigned char * InstanceKlass::get_cached_class_file_bytes() { return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); }