1 /*
2 * Copyright 2005-2008 Sun Microsystems, Inc. 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. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25
26 package com.sun.tools.javac.model;
27
28 import com.sun.tools.javac.util.*;
29 import java.lang.annotation.*;
30 import java.lang.reflect.Array;
31 import java.lang.reflect.Method;
32 import java.util.LinkedHashMap;
33 import java.util.Map;
34 import java.io.ObjectInputStream;
35 import java.io.IOException;
36 import sun.reflect.annotation.*;
37
38 import javax.lang.model.type.TypeMirror;
39 import javax.lang.model.type.MirroredTypeException;
40 import javax.lang.model.type.MirroredTypesException;
41 import com.sun.tools.javac.code.*;
42 import com.sun.tools.javac.code.Symbol.*;
43 import com.sun.tools.javac.code.Type.ArrayType;
44
45
46 /**
47 * A generator of dynamic proxy implementations of
48 * java.lang.annotation.Annotation.
49 *
50 * <p> The "dynamic proxy return form" of an annotation element value is
51 * the form used by sun.reflect.annotation.AnnotationInvocationHandler.
52 *
53 * <p><b>This is NOT part of any API supported by Sun Microsystems. If
54 * you write code that depends on this, you do so at your own risk.
55 * This code and its internal interfaces are subject to change or
56 * deletion without notice.</b>
57 */
58
59 public class AnnotationProxyMaker {
60
61 private final Attribute.Compound anno;
62 private final Class<? extends Annotation> annoType;
63
64
65 private AnnotationProxyMaker(Attribute.Compound anno,
66 Class<? extends Annotation> annoType) {
67 this.anno = anno;
68 this.annoType = annoType;
69 }
70
71
72 /**
73 * Returns a dynamic proxy for an annotation mirror.
74 */
75 public static <A extends Annotation> A generateAnnotation(
76 Attribute.Compound anno, Class<A> annoType) {
77 AnnotationProxyMaker apm = new AnnotationProxyMaker(anno, annoType);
78 return annoType.cast(apm.generateAnnotation());
79 }
80
81
82 /**
83 * Returns a dynamic proxy for an annotation mirror.
84 */
85 private Annotation generateAnnotation() {
86 return AnnotationParser.annotationForMap(annoType,
87 getAllReflectedValues());
88 }
89
90 /**
91 * Returns a map from element names to their values in "dynamic
92 * proxy return form". Includes all elements, whether explicit or
93 * defaulted.
94 */
95 private Map<String, Object> getAllReflectedValues() {
96 Map<String, Object> res = new LinkedHashMap<String, Object>();
97
98 for (Map.Entry<MethodSymbol, Attribute> entry :
99 getAllValues().entrySet()) {
100 MethodSymbol meth = entry.getKey();
101 Object value = generateValue(meth, entry.getValue());
102 if (value != null) {
103 res.put(meth.name.toString(), value);
104 } else {
105 // Ignore this element. May (properly) lead to
106 // IncompleteAnnotationException somewhere down the line.
107 }
108 }
109 return res;
110 }
111
112 /**
113 * Returns a map from element symbols to their values.
114 * Includes all elements, whether explicit or defaulted.
115 */
116 private Map<MethodSymbol, Attribute> getAllValues() {
117 Map<MethodSymbol, Attribute> res =
118 new LinkedHashMap<MethodSymbol, Attribute>();
119
120 // First find the default values.
121 ClassSymbol sym = (ClassSymbol) anno.type.tsym;
122 for (Scope.Entry e = sym.members().elems; e != null; e = e.sibling) {
123 if (e.sym.kind == Kinds.MTH) {
124 MethodSymbol m = (MethodSymbol) e.sym;
125 Attribute def = m.getDefaultValue();
126 if (def != null)
127 res.put(m, def);
128 }
129 }
130 // Next find the explicit values, possibly overriding defaults.
131 for (Pair<MethodSymbol, Attribute> p : anno.values)
132 res.put(p.fst, p.snd);
133 return res;
134 }
135
136 /**
137 * Converts an element value to its "dynamic proxy return form".
138 * Returns an exception proxy on some errors, but may return null if
139 * a useful exception cannot or should not be generated at this point.
140 */
141 private Object generateValue(MethodSymbol meth, Attribute attr) {
142 ValueVisitor vv = new ValueVisitor(meth);
143 return vv.getValue(attr);
144 }
145
146
147 private class ValueVisitor implements Attribute.Visitor {
148
149 private MethodSymbol meth; // annotation element being visited
150 private Class<?> returnClass; // return type of annotation element
151 private Object value; // value in "dynamic proxy return form"
152
153 ValueVisitor(MethodSymbol meth) {
154 this.meth = meth;
155 }
156
157 Object getValue(Attribute attr) {
158 Method method; // runtime method of annotation element
159 try {
160 method = annoType.getMethod(meth.name.toString());
161 } catch (NoSuchMethodException e) {
162 return null;
163 }
164 returnClass = method.getReturnType();
165 attr.accept(this);
166 if (!(value instanceof ExceptionProxy) &&
167 !AnnotationType.invocationHandlerReturnType(returnClass)
168 .isInstance(value)) {
169 typeMismatch(method, attr);
170 }
171 return value;
172 }
173
174
175 public void visitConstant(Attribute.Constant c) {
176 value = c.getValue();
177 }
178
179 public void visitClass(Attribute.Class c) {
180 value = new MirroredTypeExceptionProxy(c.type);
181 }
182
183 public void visitArray(Attribute.Array a) {
184 Name elemName = ((ArrayType) a.type).elemtype.tsym.name;
185
186 if (elemName == elemName.table.names.java_lang_Class) { // Class[]
187 // Construct a proxy for a MirroredTypesException
188 List<TypeMirror> elems = List.nil();
189 for (Attribute value : a.values) {
190 Type elem = ((Attribute.Class) value).type;
191 elems.add(elem);
192 }
193 value = new MirroredTypesExceptionProxy(elems);
194
195 } else {
196 int len = a.values.length;
197 Class<?> returnClassSaved = returnClass;
198 returnClass = returnClass.getComponentType();
199 try {
200 Object res = Array.newInstance(returnClass, len);
201 for (int i = 0; i < len; i++) {
202 a.values[i].accept(this);
203 if (value == null || value instanceof ExceptionProxy) {
204 return;
205 }
206 try {
207 Array.set(res, i, value);
208 } catch (IllegalArgumentException e) {
209 value = null; // indicates a type mismatch
210 return;
211 }
212 }
213 value = res;
214 } finally {
215 returnClass = returnClassSaved;
216 }
217 }
218 }
219
220 @SuppressWarnings({"unchecked", "rawtypes"})
221 public void visitEnum(Attribute.Enum e) {
222 if (returnClass.isEnum()) {
223 String constName = e.value.toString();
224 try {
225 value = Enum.valueOf((Class)returnClass, constName);
226 } catch (IllegalArgumentException ex) {
227 value = new EnumConstantNotPresentExceptionProxy(
228 (Class<Enum<?>>) returnClass, constName);
229 }
230 } else {
231 value = null; // indicates a type mismatch
232 }
233 }
234
235 public void visitCompound(Attribute.Compound c) {
236 try {
237 Class<? extends Annotation> nested =
238 returnClass.asSubclass(Annotation.class);
239 value = generateAnnotation(c, nested);
240 } catch (ClassCastException ex) {
241 value = null; // indicates a type mismatch
242 }
243 }
244
245 public void visitError(Attribute.Error e) {
246 value = null; // indicates a type mismatch
247 }
248
249
250 /**
251 * Sets "value" to an ExceptionProxy indicating a type mismatch.
252 */
253 private void typeMismatch(final Method method, final Attribute attr) {
254 value = new ExceptionProxy() {
255 static final long serialVersionUID = 269;
256 public String toString() {
257 return "<error>"; // eg: @Anno(value=<error>)
258 }
259 protected RuntimeException generateException() {
260 return new AnnotationTypeMismatchException(method,
261 attr.type.toString());
262 }
263 };
264 }
265 }
266
267
268 /**
269 * ExceptionProxy for MirroredTypeException.
270 * The toString, hashCode, and equals methods foward to the underlying
271 * type.
272 */
273 private static final class MirroredTypeExceptionProxy extends ExceptionProxy {
274 static final long serialVersionUID = 269;
275
276 private transient TypeMirror type;
277 private final String typeString;
278
279 MirroredTypeExceptionProxy(TypeMirror t) {
280 type = t;
281 typeString = t.toString();
282 }
283
284 public String toString() {
285 return typeString;
286 }
287
288 public int hashCode() {
289 return (type != null ? type : typeString).hashCode();
290 }
291
292 public boolean equals(Object obj) {
293 return type != null &&
294 obj instanceof MirroredTypeExceptionProxy &&
295 type.equals(((MirroredTypeExceptionProxy) obj).type);
296 }
297
298 protected RuntimeException generateException() {
299 return new MirroredTypeException(type);
300 }
301
302 // Explicitly set all transient fields.
303 private void readObject(ObjectInputStream s)
304 throws IOException, ClassNotFoundException {
305 s.defaultReadObject();
306 type = null;
307 }
308 }
309
310
311 /**
312 * ExceptionProxy for MirroredTypesException.
313 * The toString, hashCode, and equals methods foward to the underlying
314 * types.
315 */
316 private static final class MirroredTypesExceptionProxy extends ExceptionProxy {
317 static final long serialVersionUID = 269;
318
319 private transient List<TypeMirror> types;
320 private final String typeStrings;
321
322 MirroredTypesExceptionProxy(List<TypeMirror> ts) {
323 types = ts;
324 typeStrings = ts.toString();
325 }
326
327 public String toString() {
328 return typeStrings;
329 }
330
331 public int hashCode() {
332 return (types != null ? types : typeStrings).hashCode();
333 }
334
335 public boolean equals(Object obj) {
336 return types != null &&
337 obj instanceof MirroredTypesExceptionProxy &&
338 types.equals(
339 ((MirroredTypesExceptionProxy) obj).types);
340 }
341
342 protected RuntimeException generateException() {
343 return new MirroredTypesException(types);
344 }
345
346 // Explicitly set all transient fields.
347 private void readObject(ObjectInputStream s)
348 throws IOException, ClassNotFoundException {
349 s.defaultReadObject();
350 types = null;
351 }
352 }
353 }