1 /*
2 * Copyright (c) 2003, 2013, 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package sun.reflect.generics.reflectiveObjects;
27
28 import java.lang.annotation.*;
29 import java.lang.reflect.AnnotatedType;
30 import java.lang.reflect.Array;
31 import java.lang.reflect.Constructor;
32 import java.lang.reflect.GenericDeclaration;
33 import java.lang.reflect.Member;
34 import java.lang.reflect.Method;
35 import java.lang.reflect.Type;
36 import java.lang.reflect.TypeVariable;
37 import java.util.LinkedHashMap;
38 import java.util.Map;
39 import java.util.Objects;
40 import sun.reflect.annotation.AnnotationSupport;
41 import sun.reflect.annotation.TypeAnnotationParser;
42 import sun.reflect.annotation.AnnotationType;
43 import sun.reflect.generics.factory.GenericsFactory;
44 import sun.reflect.generics.tree.FieldTypeSignature;
45 import sun.reflect.generics.visitor.Reifier;
46 import sun.reflect.misc.ReflectUtil;
47
48 /**
49 * Implementation of {@code java.lang.reflect.TypeVariable} interface
50 * for core reflection.
51 */
52 public class TypeVariableImpl<D extends GenericDeclaration>
53 extends LazyReflectiveObjectGenerator implements TypeVariable<D> {
54 private final D genericDeclaration;
55 private final String name;
56
57 /**
58 * The upper bounds. Lazily converted from FieldTypeSignature[] to Type[].
59 * We are required to evaluate the bounds lazily, so we store them as ASTs
60 * until we are first asked for them. This also neatly solves the problem
61 * with F-bounds - you can't reify them before the formal is defined.
62 */
63 private volatile Object[] bounds;
64
65 // constructor is private to enforce access through static factory
66 private TypeVariableImpl(D decl, String n, FieldTypeSignature[] bs,
67 GenericsFactory f) {
68 super(f);
69 genericDeclaration = decl;
70 name = n;
71 bounds = bs;
72 }
73
74 /**
75 * Factory method.
76 * @param decl - the reflective object that declared the type variable
77 * that this method should create
78 * @param name - the name of the type variable to be returned
79 * @param bs - an array of ASTs representing the bounds for the type
80 * variable to be created
81 * @param f - a factory that can be used to manufacture reflective
82 * objects that represent the bounds of this type variable
83 * @return A type variable with name, bounds, declaration and factory
84 * specified
85 */
86 public static <T extends GenericDeclaration>
87 TypeVariableImpl<T> make(T decl, String name,
88 FieldTypeSignature[] bs,
89 GenericsFactory f) {
90
91 if (!((decl instanceof Class) ||
92 (decl instanceof Method) ||
93 (decl instanceof Constructor))) {
94 throw new AssertionError("Unexpected kind of GenericDeclaration" +
95 decl.getClass().toString());
96 }
97 return new TypeVariableImpl<T>(decl, name, bs, f);
98 }
99
100
101 /**
102 * Returns an array of {@code Type} objects representing the
103 * upper bound(s) of this type variable. Note that if no upper bound is
104 * explicitly declared, the upper bound is {@code Object}.
105 *
106 * <p>For each upper bound B:
107 * <ul>
108 * <li>if B is a parameterized type or a type variable, it is created,
109 * (see {@link #ParameterizedType} for the details of the creation
110 * process for parameterized types).
111 * <li>Otherwise, B is resolved.
112 * </ul>
113 *
114 * @throws {@code TypeNotPresentException} if any of the
115 * bounds refers to a non-existent type declaration
116 * @throws {@code MalformedParameterizedTypeException} if any of the
117 * bounds refer to a parameterized type that cannot be instantiated
118 * for any reason
119 * @return an array of Types representing the upper bound(s) of this
120 * type variable
121 */
122 public Type[] getBounds() {
123 Object[] value = bounds;
124 if (value instanceof FieldTypeSignature[]) {
125 value = reifyBounds((FieldTypeSignature[])value);
126 bounds = value;
127 }
128 return (Type[])value.clone();
129 }
130
131 /**
132 * Returns the {@code GenericDeclaration} object representing the
133 * generic declaration that declared this type variable.
134 *
135 * @return the generic declaration that declared this type variable.
136 *
137 * @since 1.5
138 */
139 public D getGenericDeclaration() {
140 if (genericDeclaration instanceof Class)
141 ReflectUtil.checkPackageAccess((Class)genericDeclaration);
142 else if ((genericDeclaration instanceof Method) ||
143 (genericDeclaration instanceof Constructor))
144 ReflectUtil.conservativeCheckMemberAccess((Member)genericDeclaration);
145 else
146 throw new AssertionError("Unexpected kind of GenericDeclaration");
147 return genericDeclaration;
148 }
149
150
151 /**
152 * Returns the name of this type variable, as it occurs in the source code.
153 *
154 * @return the name of this type variable, as it appears in the source code
155 */
156 public String getName() { return name; }
157
158 public String toString() {return getName();}
159
160 @Override
161 public boolean equals(Object o) {
162 if (o instanceof TypeVariable &&
163 o.getClass() == TypeVariableImpl.class) {
164 TypeVariable<?> that = (TypeVariable<?>) o;
165
166 GenericDeclaration thatDecl = that.getGenericDeclaration();
167 String thatName = that.getName();
168
169 return Objects.equals(genericDeclaration, thatDecl) &&
170 Objects.equals(name, thatName);
171
172 } else
173 return false;
174 }
175
176 @Override
177 public int hashCode() {
178 return genericDeclaration.hashCode() ^ name.hashCode();
179 }
180
181 // Implementations of AnnotatedElement methods.
182 @SuppressWarnings("unchecked")
183 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
184 Objects.requireNonNull(annotationClass);
185 // T is an Annotation type, the return value of get will be an annotation
186 return (T)mapAnnotations(getAnnotations()).get(annotationClass);
187 }
188
189 public <T extends Annotation> T getDeclaredAnnotation(Class<T> annotationClass) {
190 Objects.requireNonNull(annotationClass);
191 return getAnnotation(annotationClass);
192 }
193
194 @Override
195 public <T extends Annotation> T[] getAnnotationsByType(Class<T> annotationClass) {
196 Objects.requireNonNull(annotationClass);
197 return AnnotationSupport.getDirectlyAndIndirectlyPresent(mapAnnotations(getAnnotations()), annotationClass);
198 }
199
200 @Override
201 public <T extends Annotation> T[] getDeclaredAnnotationsByType(Class<T> annotationClass) {
202 Objects.requireNonNull(annotationClass);
203 return getAnnotationsByType(annotationClass);
204 }
205
206 public Annotation[] getAnnotations() {
207 int myIndex = typeVarIndex();
208 if (myIndex < 0)
209 throw new AssertionError("Index must be non-negative.");
210 return TypeAnnotationParser.parseTypeVariableAnnotations(getGenericDeclaration(), myIndex);
211 }
212
213 public Annotation[] getDeclaredAnnotations() {
214 return getAnnotations();
215 }
216
217 public AnnotatedType[] getAnnotatedBounds() {
218 return TypeAnnotationParser.parseAnnotatedBounds(getBounds(),
219 getGenericDeclaration(),
220 typeVarIndex());
221 }
222
223 private static final Annotation[] EMPTY_ANNOTATION_ARRAY = new Annotation[0];
224
225 // Helpers for annotation methods
226 private int typeVarIndex() {
227 TypeVariable<?>[] tVars = getGenericDeclaration().getTypeParameters();
228 int i = -1;
229 for (TypeVariable<?> v : tVars) {
230 i++;
231 if (equals(v))
232 return i;
233 }
234 return -1;
235 }
236
237 private static Map<Class<? extends Annotation>, Annotation> mapAnnotations(Annotation[] annos) {
238 Map<Class<? extends Annotation>, Annotation> result =
239 new LinkedHashMap<>();
240 for (Annotation a : annos) {
241 Class<? extends Annotation> klass = a.annotationType();
242 AnnotationType type = AnnotationType.getInstance(klass);
243 if (type.retention() == RetentionPolicy.RUNTIME)
244 if (result.put(klass, a) != null)
245 throw new AnnotationFormatError("Duplicate annotation for class: "+klass+": " + a);
246 }
247 return result;
248 }
249 }