1 /*
2 * Copyright (c) 2011, 2017, 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.HotSpotModifiers.jvmFieldModifiers;
26 import static jdk.vm.ci.hotspot.HotSpotVMConfig.config;
27
28 import java.lang.annotation.Annotation;
29 import java.lang.reflect.Field;
30
31 import jdk.internal.vm.annotation.Stable;
32
33 import jdk.vm.ci.meta.JavaConstant;
34 import jdk.vm.ci.meta.JavaType;
35 import jdk.vm.ci.meta.ResolvedJavaType;
36 import jdk.vm.ci.meta.UnresolvedJavaType;
37
38 /**
39 * Represents a field in a HotSpot type.
40 */
41 class HotSpotResolvedJavaFieldImpl implements HotSpotResolvedJavaField {
42
43 private final HotSpotResolvedObjectTypeImpl holder;
44 private JavaType type;
45 private final int offset;
46 private final short index;
47
48 /**
49 * This value contains all flags as stored in the VM including internal ones.
50 */
51 private final int modifiers;
52
53 HotSpotResolvedJavaFieldImpl(HotSpotResolvedObjectTypeImpl holder, JavaType type, long offset, int modifiers, int index) {
54 this.holder = holder;
55 this.type = type;
56 this.index = (short) index;
57 assert this.index == index;
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 return true;
75 }
76 }
77 return false;
78 }
79
80 @Override
81 public int hashCode() {
82 return holder.hashCode() ^ offset;
83 }
84
85 @Override
86 public int getModifiers() {
87 return modifiers & jvmFieldModifiers();
88 }
89
90 @Override
91 public boolean isInternal() {
92 return (modifiers & config().jvmAccFieldInternal) != 0;
93 }
94
95 /**
96 * Determines if a given object contains this field.
97 *
98 * @return true iff this is a non-static field and its declaring class is assignable from
99 * {@code object}'s class
100 */
101 @Override
102 public boolean isInObject(JavaConstant constant) {
103 if (isStatic()) {
104 return false;
105 }
106 Object object = ((HotSpotObjectConstantImpl) constant).object();
107 return getDeclaringClass().isAssignableFrom(HotSpotResolvedObjectTypeImpl.fromObjectClass(object.getClass()));
108 }
109
110 @Override
111 public HotSpotResolvedObjectTypeImpl getDeclaringClass() {
112 return holder;
113 }
114
115 @Override
116 public String getName() {
117 return holder.createFieldInfo(index).getName();
118 }
119
120 @Override
121 public JavaType getType() {
122 // Pull field into local variable to prevent a race causing
123 // a ClassCastException below
124 JavaType currentType = type;
125 if (currentType instanceof UnresolvedJavaType) {
126 // Don't allow unresolved types to hang around forever
127 UnresolvedJavaType unresolvedType = (UnresolvedJavaType) currentType;
128 ResolvedJavaType resolved = holder.lookupType(unresolvedType, false);
129 if (resolved != null) {
130 type = resolved;
131 }
132 }
133 return type;
134 }
135
136 @Override
137 public int getOffset() {
138 return offset;
139 }
140
141 @Override
142 public String toString() {
143 return format("HotSpotField<%H.%n %t:") + offset + ">";
144 }
145
146 @Override
147 public boolean isSynthetic() {
148 return (config().jvmAccSynthetic & modifiers) != 0;
149 }
150
151 /**
152 * Checks if this field has the {@link Stable} annotation.
153 *
154 * @return true if field has {@link Stable} annotation, false otherwise
155 */
156 @Override
157 public boolean isStable() {
158 return (config().jvmAccFieldStable & modifiers) != 0;
159 }
160
161 @Override
162 public Annotation[] getAnnotations() {
163 Field javaField = toJava();
164 if (javaField != null) {
165 return javaField.getAnnotations();
166 }
167 return new Annotation[0];
168 }
169
170 @Override
171 public Annotation[] getDeclaredAnnotations() {
172 Field javaField = toJava();
173 if (javaField != null) {
174 return javaField.getDeclaredAnnotations();
175 }
176 return new Annotation[0];
177 }
178
179 @Override
180 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
181 Field javaField = toJava();
182 if (javaField != null) {
183 return javaField.getAnnotation(annotationClass);
184 }
185 return null;
186 }
187
188 private Field toJava() {
189 if (isInternal()) {
190 return null;
191 }
192 try {
193 return holder.mirror().getDeclaredField(getName());
194 } catch (NoSuchFieldException e) {
195 return null;
196 }
197 }
198 }