1 /*
2 * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/javaClasses.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "gc/shared/collectedHeap.inline.hpp"
30 #include "gc/shared/gcLocker.hpp"
31 #include "jvmtifiles/jvmti.h"
32 #include "memory/universe.inline.hpp"
33 #include "oops/arrayKlass.hpp"
34 #include "oops/arrayOop.hpp"
35 #include "oops/instanceKlass.hpp"
36 #include "oops/objArrayOop.hpp"
37 #include "oops/oop.inline.hpp"
38
39 int ArrayKlass::static_size(int header_size) {
40 // size of an array klass object
41 assert(header_size <= InstanceKlass::header_size(), "bad header size");
42 // If this assert fails, see comments in base_create_array_klass.
43 header_size = InstanceKlass::header_size();
44 int vtable_len = Universe::base_vtable_size();
45 int size = header_size + vtable_len;
46 return align_object_size(size);
47 }
48
49
50 Klass* ArrayKlass::java_super() const {
51 if (super() == NULL) return NULL; // bootstrap case
52 // Array klasses have primary supertypes which are not reported to Java.
53 // Example super chain: String[][] -> Object[][] -> Object[] -> Object
54 return SystemDictionary::Object_klass();
55 }
56
57
58 oop ArrayKlass::multi_allocate(int rank, jint* sizes, TRAPS) {
59 ShouldNotReachHere();
60 return NULL;
61 }
62
63 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
64 Klass* ArrayKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
65 // There are no fields in an array klass but look to the super class (Object)
66 assert(super(), "super klass must be present");
67 return super()->find_field(name, sig, fd);
68 }
69
70 Method* ArrayKlass::uncached_lookup_method(const Symbol* name,
71 const Symbol* signature,
72 OverpassLookupMode overpass_mode) const {
73 // There are no methods in an array klass but the super class (Object) has some
74 assert(super(), "super klass must be present");
75 // Always ignore overpass methods in superclasses, although technically the
76 // super klass of an array, (j.l.Object) should not have
77 // any overpass methods present.
78 return super()->uncached_lookup_method(name, signature, Klass::skip_overpass);
79 }
80
81 ArrayKlass::ArrayKlass(Symbol* name) :
82 _dimension(1),
83 _higher_dimension(NULL),
84 _lower_dimension(NULL),
85 // Arrays don't add any new methods, so their vtable is the same size as
86 // the vtable of klass Object.
87 _vtable_len(Universe::base_vtable_size()) {
88 set_name(name);
89 set_super(Universe::is_bootstrapping() ? (Klass*)NULL : SystemDictionary::Object_klass());
90 set_layout_helper(Klass::_lh_neutral_value);
91 set_is_cloneable(); // All arrays are considered to be cloneable (See JLS 20.1.5)
92 TRACE_INIT_ID(this);
93 }
94
95
96 // Initialization of vtables and mirror object is done separatly from base_create_array_klass,
97 // since a GC can happen. At this point all instance variables of the ArrayKlass must be setup.
98 void ArrayKlass::complete_create_array_klass(ArrayKlass* k, KlassHandle super_klass, TRAPS) {
99 ResourceMark rm(THREAD);
100 k->initialize_supers(super_klass(), CHECK);
101 k->vtable()->initialize_vtable(false, CHECK);
102 java_lang_Class::create_mirror(k, Handle(THREAD, k->class_loader()), Handle(NULL), CHECK);
103 }
104
105 GrowableArray<Klass*>* ArrayKlass::compute_secondary_supers(int num_extra_slots) {
106 // interfaces = { cloneable_klass, serializable_klass };
107 assert(num_extra_slots == 0, "sanity of primitive array type");
108 // Must share this for correct bootstrapping!
109 set_secondary_supers(Universe::the_array_interfaces_array());
110 return NULL;
111 }
112
113 bool ArrayKlass::compute_is_subtype_of(Klass* k) {
114 // An array is a subtype of Serializable, Clonable, and Object
115 return k == SystemDictionary::Object_klass()
116 || k == SystemDictionary::Cloneable_klass()
117 || k == SystemDictionary::Serializable_klass();
118 }
119
120
121 inline intptr_t* ArrayKlass::start_of_vtable() const {
122 // all vtables start at the same place, that's why we use InstanceKlass::header_size here
123 return ((intptr_t*)this) + InstanceKlass::header_size();
124 }
125
126
127 klassVtable* ArrayKlass::vtable() const {
128 KlassHandle kh(Thread::current(), this);
129 return new klassVtable(kh, start_of_vtable(), vtable_length() / vtableEntry::size());
130 }
131
132
133 objArrayOop ArrayKlass::allocate_arrayArray(int n, int length, TRAPS) {
134 if (length < 0) {
135 THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
136 }
137 if (length > arrayOopDesc::max_array_length(T_ARRAY)) {
138 report_java_out_of_memory("Requested array size exceeds VM limit");
139 JvmtiExport::post_array_size_exhausted();
140 THROW_OOP_0(Universe::out_of_memory_error_array_size());
141 }
142 int size = objArrayOopDesc::object_size(length);
143 Klass* k = array_klass(n+dimension(), CHECK_0);
144 ArrayKlass* ak = ArrayKlass::cast(k);
145 objArrayOop o =
146 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_0);
147 // initialization to NULL not necessary, area already cleared
148 return o;
149 }
150
151 void ArrayKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
152 Klass* k = this;
153 // Iterate over this array klass and all higher dimensions
154 while (k != NULL) {
155 f(k, CHECK);
156 k = ArrayKlass::cast(k)->higher_dimension();
157 }
158 }
159
160 void ArrayKlass::array_klasses_do(void f(Klass* k)) {
161 Klass* k = this;
162 // Iterate over this array klass and all higher dimensions
163 while (k != NULL) {
164 f(k);
165 k = ArrayKlass::cast(k)->higher_dimension();
166 }
167 }
168
169 // JVM support
170
171 jint ArrayKlass::compute_modifier_flags(TRAPS) const {
172 return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC;
173 }
174
175 // JVMTI support
176
177 jint ArrayKlass::jvmti_class_status() const {
178 return JVMTI_CLASS_STATUS_ARRAY;
179 }
180
181 void ArrayKlass::remove_unshareable_info() {
182 Klass::remove_unshareable_info();
183 }
184
185 void ArrayKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
186 assert(loader_data == ClassLoaderData::the_null_class_loader_data(), "array classes belong to null loader");
187 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
188 // Klass recreates the component mirror also
189 }
190
191 // Printing
192
193 void ArrayKlass::print_on(outputStream* st) const {
194 assert(is_klass(), "must be klass");
195 Klass::print_on(st);
196 }
197
198 void ArrayKlass::print_value_on(outputStream* st) const {
199 assert(is_klass(), "must be klass");
200 for(int index = 0; index < dimension(); index++) {
201 st->print("[]");
202 }
203 }
204
205 void ArrayKlass::oop_print_on(oop obj, outputStream* st) {
206 assert(obj->is_array(), "must be array");
207 Klass::oop_print_on(obj, st);
208 st->print_cr(" - length: %d", arrayOop(obj)->length());
209 }
210
211
212 // Verification
213
214 void ArrayKlass::verify_on(outputStream* st) {
215 Klass::verify_on(st);
216 }
217
218 void ArrayKlass::oop_verify_on(oop obj, outputStream* st) {
219 guarantee(obj->is_array(), "must be array");
220 arrayOop a = arrayOop(obj);
221 guarantee(a->length() >= 0, "array with negative length?");
222 }
--- EOF ---