/* * Copyright (c) 1997, 2018, 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/javaClasses.hpp" #include "classfile/systemDictionary.hpp" #include "classfile/vmSymbols.hpp" #include "gc/shared/collectedHeap.inline.hpp" #include "jvmtifiles/jvmti.h" #include "memory/metaspaceClosure.hpp" #include "memory/resourceArea.hpp" #include "memory/universe.hpp" #include "oops/arrayKlass.hpp" #include "oops/arrayOop.hpp" #include "oops/instanceKlass.hpp" #include "oops/objArrayOop.hpp" #include "oops/oop.inline.hpp" #include "runtime/handles.inline.hpp" int ArrayKlass::static_size(int header_size) { // size of an array klass object assert(header_size <= InstanceKlass::header_size(), "bad header size"); // If this assert fails, see comments in base_create_array_klass. header_size = InstanceKlass::header_size(); int vtable_len = Universe::base_vtable_size(); int size = header_size + vtable_len; return align_metadata_size(size); } Klass* ArrayKlass::java_super() const { if (super() == NULL) return NULL; // bootstrap case // Array klasses have primary supertypes which are not reported to Java. // Example super chain: String[][] -> Object[][] -> Object[] -> Object return SystemDictionary::Object_klass(); } oop ArrayKlass::multi_allocate(int rank, jint* sizes, TRAPS) { ShouldNotReachHere(); return NULL; } // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined Klass* ArrayKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { // There are no fields in an array klass but look to the super class (Object) assert(super(), "super klass must be present"); return super()->find_field(name, sig, fd); } Method* ArrayKlass::uncached_lookup_method(const Symbol* name, const Symbol* signature, OverpassLookupMode overpass_mode) const { // There are no methods in an array klass but the super class (Object) has some assert(super(), "super klass must be present"); // Always ignore overpass methods in superclasses, although technically the // super klass of an array, (j.l.Object) should not have // any overpass methods present. return super()->uncached_lookup_method(name, signature, Klass::skip_overpass); } ArrayKlass::ArrayKlass(Symbol* name) : _dimension(1), _higher_dimension(NULL), _lower_dimension(NULL) { // Arrays don't add any new methods, so their vtable is the same size as // the vtable of klass Object. set_vtable_length(Universe::base_vtable_size()); set_name(name); set_super(Universe::is_bootstrapping() ? (Klass*)NULL : SystemDictionary::Object_klass()); set_layout_helper(Klass::_lh_neutral_value); set_is_cloneable(); // All arrays are considered to be cloneable (See JLS 20.1.5) JFR_ONLY(INIT_ID(this);) } // Initialization of vtables and mirror object is done separatly from base_create_array_klass, // since a GC can happen. At this point all instance variables of the ArrayKlass must be setup. void ArrayKlass::complete_create_array_klass(ArrayKlass* k, Klass* super_klass, ModuleEntry* module_entry, TRAPS) { ResourceMark rm(THREAD); k->initialize_supers(super_klass, NULL, CHECK); k->vtable().initialize_vtable(false, CHECK); // During bootstrapping, before java.base is defined, the module_entry may not be present yet. // These classes will be put on a fixup list and their module fields will be patched once // java.base is defined. assert((module_entry != NULL) || ((module_entry == NULL) && !ModuleEntryTable::javabase_defined()), "module entry not available post " JAVA_BASE_NAME " definition"); oop module = (module_entry != NULL) ? module_entry->module() : (oop)NULL; java_lang_Class::create_mirror(k, Handle(THREAD, k->class_loader()), Handle(THREAD, module), Handle(), CHECK); } GrowableArray* ArrayKlass::compute_secondary_supers(int num_extra_slots, Array* transitive_interfaces) { // interfaces = { cloneable_klass, serializable_klass }; assert(num_extra_slots == 0, "sanity of primitive array type"); assert(transitive_interfaces == NULL, "sanity"); // Must share this for correct bootstrapping! set_secondary_supers(Universe::the_array_interfaces_array()); return NULL; } bool ArrayKlass::compute_is_subtype_of(Klass* k) { // An array is a subtype of Serializable, Clonable, and Object return k == SystemDictionary::Object_klass() || k == SystemDictionary::Cloneable_klass() || k == SystemDictionary::Serializable_klass(); } objArrayOop ArrayKlass::allocate_arrayArray(int n, int length, TRAPS) { if (length < 0) { ResourceMark rm(THREAD); stringStream ss; ss.print("%d", length); THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), ss.as_string()); } if (length > arrayOopDesc::max_array_length(T_ARRAY)) { 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* k = array_klass(n+dimension(), CHECK_0); ArrayKlass* ak = ArrayKlass::cast(k); objArrayOop o = (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_0); // initialization to NULL not necessary, area already cleared return o; } void ArrayKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) { Klass* k = this; // Iterate over this array klass and all higher dimensions while (k != NULL) { f(k, CHECK); k = ArrayKlass::cast(k)->higher_dimension(); } } void ArrayKlass::array_klasses_do(void f(Klass* k)) { Klass* k = this; // Iterate over this array klass and all higher dimensions while (k != NULL) { f(k); k = ArrayKlass::cast(k)->higher_dimension(); } } // JVM support jint ArrayKlass::compute_modifier_flags(TRAPS) const { return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC; } // JVMTI support jint ArrayKlass::jvmti_class_status() const { return JVMTI_CLASS_STATUS_ARRAY; } void ArrayKlass::metaspace_pointers_do(MetaspaceClosure* it) { Klass::metaspace_pointers_do(it); ResourceMark rm; log_trace(cds)("Iter(ArrayKlass): %p (%s)", this, external_name()); // need to cast away volatile it->push((Klass**)&_higher_dimension); it->push((Klass**)&_lower_dimension); } void ArrayKlass::remove_unshareable_info() { Klass::remove_unshareable_info(); if (_higher_dimension != NULL) { ArrayKlass *ak = ArrayKlass::cast(higher_dimension()); ak->remove_unshareable_info(); } } void ArrayKlass::remove_java_mirror() { Klass::remove_java_mirror(); if (_higher_dimension != NULL) { ArrayKlass *ak = ArrayKlass::cast(higher_dimension()); ak->remove_java_mirror(); } } void ArrayKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) { assert(loader_data == ClassLoaderData::the_null_class_loader_data(), "array classes belong to null loader"); Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); // Klass recreates the component mirror also if (_higher_dimension != NULL) { ArrayKlass *ak = ArrayKlass::cast(higher_dimension()); ak->restore_unshareable_info(loader_data, protection_domain, CHECK); } } // Printing void ArrayKlass::print_on(outputStream* st) const { assert(is_klass(), "must be klass"); Klass::print_on(st); } void ArrayKlass::print_value_on(outputStream* st) const { assert(is_klass(), "must be klass"); for(int index = 0; index < dimension(); index++) { st->print("[]"); } } void ArrayKlass::oop_print_on(oop obj, outputStream* st) { assert(obj->is_array(), "must be array"); Klass::oop_print_on(obj, st); st->print_cr(" - length: %d", arrayOop(obj)->length()); } // Verification void ArrayKlass::verify_on(outputStream* st) { Klass::verify_on(st); } void ArrayKlass::oop_verify_on(oop obj, outputStream* st) { guarantee(obj->is_array(), "must be array"); arrayOop a = arrayOop(obj); guarantee(a->length() >= 0, "array with negative length?"); }