1 /*
2 * Copyright (c) 2011, 2015, 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 package jdk.vm.ci.hotspot;
24
25 import static jdk.vm.ci.hotspot.HotSpotVMConfig.config;
26
27 import java.lang.annotation.Annotation;
28 import java.lang.reflect.Field;
29
30 import jdk.internal.vm.annotation.Stable;
31 import jdk.vm.ci.common.JVMCIError;
32 import jdk.vm.ci.hotspot.HotSpotJVMCIRuntime.Option;
33 import jdk.vm.ci.meta.JavaType;
34 import jdk.vm.ci.meta.MetaAccessProvider;
35 import jdk.vm.ci.meta.ModifiersProvider;
36 import jdk.vm.ci.meta.ResolvedJavaField;
37 import jdk.vm.ci.meta.ResolvedJavaType;
38
39 /**
40 * Represents a field in a HotSpot type.
41 */
42 class HotSpotResolvedJavaFieldImpl implements HotSpotResolvedJavaField {
43
44 private final HotSpotResolvedObjectTypeImpl holder;
45 private final String name;
46 private JavaType type;
47 private final int offset;
48
49 /**
50 * This value contains all flags as stored in the VM including internal ones.
51 */
52 private final int modifiers;
53
54 HotSpotResolvedJavaFieldImpl(HotSpotResolvedObjectTypeImpl holder, String name, JavaType type, long offset, int modifiers) {
55 this.holder = holder;
56 this.name = name;
57 this.type = type;
58 assert offset != -1;
59 assert offset == (int) offset : "offset larger than int";
60 this.offset = (int) offset;
61 this.modifiers = modifiers;
62 }
63
64 @Override
65 public boolean equals(Object obj) {
66 if (this == obj) {
67 return true;
68 }
69 if (obj instanceof HotSpotResolvedJavaField) {
70 HotSpotResolvedJavaFieldImpl that = (HotSpotResolvedJavaFieldImpl) obj;
71 if (that.offset != this.offset || that.isStatic() != this.isStatic()) {
72 return false;
73 } else if (this.holder.equals(that.holder)) {
74 assert this.name.equals(that.name) && this.type.equals(that.type);
75 return true;
76 }
77 }
78 return false;
79 }
80
81 @Override
82 public int hashCode() {
83 return name.hashCode();
84 }
85
86 @Override
87 public int getModifiers() {
88 return modifiers & ModifiersProvider.jvmFieldModifiers();
89 }
90
91 @Override
92 public boolean isInternal() {
93 return (modifiers & config().jvmAccFieldInternal) != 0;
94 }
95
96 /**
97 * Determines if a given object contains this field.
98 *
99 * @return true iff this is a non-static field and its declaring class is assignable from
100 * {@code object}'s class
101 */
102 public boolean isInObject(Object object) {
103 if (isStatic()) {
104 return false;
105 }
106 return getDeclaringClass().isAssignableFrom(HotSpotResolvedObjectTypeImpl.fromObjectClass(object.getClass()));
107 }
108
109 @Override
110 public HotSpotResolvedObjectTypeImpl getDeclaringClass() {
111 return holder;
112 }
113
114 @Override
115 public String getName() {
116 return name;
117 }
118
119 @Override
120 public JavaType getType() {
121 // Pull field into local variable to prevent a race causing
122 // a ClassCastException below
123 JavaType currentType = type;
124 if (currentType instanceof HotSpotUnresolvedJavaType) {
125 // Don't allow unresolved types to hang around forever
126 HotSpotUnresolvedJavaType unresolvedType = (HotSpotUnresolvedJavaType) currentType;
127 ResolvedJavaType resolved = unresolvedType.reresolve(holder);
128 if (resolved != null) {
129 type = resolved;
130 }
131 }
132 return type;
133 }
134
135 public int offset() {
136 return offset;
137 }
138
139 @Override
140 public String toString() {
141 return format("HotSpotField<%H.%n %t:") + offset + ">";
142 }
143
144 @Override
145 public boolean isSynthetic() {
146 return (config().jvmAccSynthetic & modifiers) != 0;
147 }
148
149 /**
150 * Checks if this field has the {@link Stable} annotation.
151 *
152 * @return true if field has {@link Stable} annotation, false otherwise
153 */
154 public boolean isStable() {
155 return (config().jvmAccFieldStable & modifiers) != 0;
156 }
157
158 @Override
159 public Annotation[] getAnnotations() {
160 Field javaField = toJava();
161 if (javaField != null) {
162 return javaField.getAnnotations();
163 }
164 return new Annotation[0];
165 }
166
167 @Override
168 public Annotation[] getDeclaredAnnotations() {
169 Field javaField = toJava();
170 if (javaField != null) {
171 return javaField.getDeclaredAnnotations();
172 }
173 return new Annotation[0];
174 }
175
176 @Override
177 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
178 Field javaField = toJava();
179 if (javaField != null) {
180 return javaField.getAnnotation(annotationClass);
181 }
182 return null;
183 }
184
185 private Field toJavaCache;
186
187 private Field toJava() {
188 if (toJavaCache != null) {
189 return toJavaCache;
190 }
191
192 if (isInternal()) {
193 return null;
194 }
195 try {
196 return toJavaCache = holder.mirror().getDeclaredField(name);
197 } catch (NoSuchFieldException | NoClassDefFoundError e) {
198 return null;
199 }
200 }
201 }