1 /*
2 * Copyright (c) 2005, 2019, 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 com.sun.tools.javac.model;
27
28 import java.io.IOException;
29 import java.io.ObjectInputStream;
30 import java.lang.annotation.*;
31 import java.lang.reflect.Array;
32 import java.lang.reflect.Method;
33 import java.util.LinkedHashMap;
34 import java.util.Map;
35 import java.util.stream.Collectors;
36 import sun.reflect.annotation.*;
37
38 import javax.lang.model.type.MirroredTypeException;
39 import javax.lang.model.type.MirroredTypesException;
40 import javax.lang.model.type.TypeMirror;
41
42 import com.sun.tools.javac.code.*;
43 import com.sun.tools.javac.code.Symbol.*;
44 import com.sun.tools.javac.code.Type.ArrayType;
45 import com.sun.tools.javac.util.*;
46
47 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
48 import static com.sun.tools.javac.code.Kinds.Kind.*;
49
50 /**
51 * A generator of dynamic proxy implementations of
52 * java.lang.annotation.Annotation.
53 *
54 * <p> The "dynamic proxy return form" of an annotation element value is
55 * the form used by sun.reflect.annotation.AnnotationInvocationHandler.
56 *
57 * <p><b>This is NOT part of any supported API.
58 * If you write code that depends on this, you do so at your own risk.
59 * This code and its internal interfaces are subject to change or
60 * deletion without notice.</b>
61 */
62
63 public class AnnotationProxyMaker {
64
65 private final Attribute.Compound anno;
66 private final Class<? extends Annotation> annoType;
67
68
69 private AnnotationProxyMaker(Attribute.Compound anno,
70 Class<? extends Annotation> annoType) {
71 this.anno = anno;
72 this.annoType = annoType;
73 }
74
75
76 /**
77 * Returns a dynamic proxy for an annotation mirror.
78 */
79 public static <A extends Annotation> A generateAnnotation(
80 Attribute.Compound anno, Class<A> annoType) {
81 AnnotationProxyMaker apm = new AnnotationProxyMaker(anno, annoType);
82 return annoType.cast(apm.generateAnnotation());
83 }
84
85
86 /**
87 * Returns a dynamic proxy for an annotation mirror.
88 */
89 private Annotation generateAnnotation() {
90 return AnnotationParser.annotationForMap(annoType,
91 getAllReflectedValues());
92 }
93
94 /**
95 * Returns a map from element names to their values in "dynamic
96 * proxy return form". Includes all elements, whether explicit or
97 * defaulted.
98 */
99 private Map<String, Object> getAllReflectedValues() {
100 Map<String, Object> res = new LinkedHashMap<>();
101
102 for (Map.Entry<MethodSymbol, Attribute> entry :
103 getAllValues().entrySet()) {
104 MethodSymbol meth = entry.getKey();
105 Object value = generateValue(meth, entry.getValue());
106 if (value != null) {
107 res.put(meth.name.toString(), value);
108 } else {
109 // Ignore this element. May (properly) lead to
110 // IncompleteAnnotationException somewhere down the line.
111 }
112 }
113 return res;
114 }
115
116 /**
117 * Returns a map from element symbols to their values.
118 * Includes all elements, whether explicit or defaulted.
119 */
120 private Map<MethodSymbol, Attribute> getAllValues() {
121 Map<MethodSymbol, Attribute> res = new LinkedHashMap<>();
122
123 // First find the default values.
124 ClassSymbol sym = (ClassSymbol) anno.type.tsym;
125 for (Symbol s : sym.members().getSymbols(NON_RECURSIVE)) {
126 if (s.kind == MTH) {
127 MethodSymbol m = (MethodSymbol) s;
128 Attribute def = m.getDefaultValue();
129 if (def != null)
130 res.put(m, def);
131 }
132 }
133 // Next find the explicit values, possibly overriding defaults.
134 for (Pair<MethodSymbol, Attribute> p : anno.values)
135 res.put(p.fst, p.snd);
136 return res;
137 }
138
139 /**
140 * Converts an element value to its "dynamic proxy return form".
141 * Returns an exception proxy on some errors, but may return null if
142 * a useful exception cannot or should not be generated at this point.
143 */
144 private Object generateValue(MethodSymbol meth, Attribute attr) {
145 ValueVisitor vv = new ValueVisitor(meth);
146 return vv.getValue(attr);
147 }
148
149
150 private class ValueVisitor implements Attribute.Visitor {
151
152 private MethodSymbol meth; // annotation element being visited
153 private Class<?> returnClass; // return type of annotation element
154 private Object value; // value in "dynamic proxy return form"
155
156 ValueVisitor(MethodSymbol meth) {
157 this.meth = meth;
158 }
159
160 Object getValue(Attribute attr) {
161 Method method; // runtime method of annotation element
162 try {
163 method = annoType.getMethod(meth.name.toString());
164 } catch (NoSuchMethodException e) {
165 return null;
166 }
167 returnClass = method.getReturnType();
168 attr.accept(this);
169 if (!(value instanceof ExceptionProxy) &&
170 !AnnotationType.invocationHandlerReturnType(returnClass)
171 .isInstance(value)) {
172 typeMismatch(method, attr);
173 }
174 return value;
175 }
176
177
178 public void visitConstant(Attribute.Constant c) {
179 value = c.getValue();
180 }
181
182 public void visitClass(Attribute.Class c) {
183 value = new MirroredTypeExceptionProxy(c.classType);
184 }
185
186 public void visitArray(Attribute.Array a) {
187 Name elemName = ((ArrayType) a.type).elemtype.tsym.getQualifiedName();
188
189 if (elemName.equals(elemName.table.names.java_lang_Class)) { // Class[]
190 // Construct a proxy for a MirroredTypesException
191 ListBuffer<TypeMirror> elems = new ListBuffer<>();
192 for (Attribute value : a.values) {
193 Type elem = ((Attribute.Class) value).classType;
194 elems.append(elem);
195 }
196 value = new MirroredTypesExceptionProxy(elems.toList());
197
198 } else {
199 int len = a.values.length;
200 Class<?> returnClassSaved = returnClass;
201 returnClass = returnClass.getComponentType();
202 try {
203 Object res = Array.newInstance(returnClass, len);
204 for (int i = 0; i < len; i++) {
205 a.values[i].accept(this);
206 if (value == null || value instanceof ExceptionProxy) {
207 return;
208 }
209 try {
210 Array.set(res, i, value);
211 } catch (IllegalArgumentException e) {
212 value = null; // indicates a type mismatch
213 return;
214 }
215 }
216 value = res;
217 } finally {
218 returnClass = returnClassSaved;
219 }
220 }
221 }
222
223 @SuppressWarnings({"unchecked", "rawtypes"})
224 public void visitEnum(Attribute.Enum e) {
225 if (returnClass.isEnum()) {
226 String constName = e.value.toString();
227 try {
228 value = Enum.valueOf((Class)returnClass, constName);
229 } catch (IllegalArgumentException ex) {
230 value = new EnumConstantNotPresentExceptionProxy(
231 (Class<Enum<?>>) returnClass, constName);
232 }
233 } else {
234 value = null; // indicates a type mismatch
235 }
236 }
237
238 public void visitCompound(Attribute.Compound c) {
239 try {
240 Class<? extends Annotation> nested =
241 returnClass.asSubclass(Annotation.class);
242 value = generateAnnotation(c, nested);
243 } catch (ClassCastException ex) {
244 value = null; // indicates a type mismatch
245 }
246 }
247
248 public void visitError(Attribute.Error e) {
249 if (e instanceof Attribute.UnresolvedClass)
250 value = new MirroredTypeExceptionProxy(((Attribute.UnresolvedClass)e).classType);
251 else
252 value = null; // indicates a type mismatch
253 }
254
255
256 /**
257 * Sets "value" to an ExceptionProxy indicating a type mismatch.
258 */
259 private void typeMismatch(Method method, final Attribute attr) {
260 class AnnotationTypeMismatchExceptionProxy extends ExceptionProxy {
261 static final long serialVersionUID = 269;
262 transient final Method method;
263 AnnotationTypeMismatchExceptionProxy(Method method) {
264 this.method = method;
265 }
266 public String toString() {
267 return "<error>"; // eg: @Anno(value=<error>)
268 }
269 protected RuntimeException generateException() {
270 return new AnnotationTypeMismatchException(method,
271 attr.type.toString());
272 }
273 }
274 value = new AnnotationTypeMismatchExceptionProxy(method);
275 }
276 }
277
278
279 /**
280 * ExceptionProxy for MirroredTypeException.
281 * The toString, hashCode, and equals methods forward to the underlying
282 * type.
283 */
284 private static final class MirroredTypeExceptionProxy extends ExceptionProxy {
285 static final long serialVersionUID = 269;
286
287 private transient TypeMirror type;
288 private final String typeString;
289
290 MirroredTypeExceptionProxy(TypeMirror t) {
291 type = t;
292 typeString = t.toString();
293 }
294
295 public String toString() {
296 return typeString + ".class";
297 }
298
299 public int hashCode() {
300 return (type != null ? type : typeString).hashCode();
301 }
302
303 public boolean equals(Object obj) {
304 return type != null &&
305 obj instanceof MirroredTypeExceptionProxy &&
306 type.equals(((MirroredTypeExceptionProxy) obj).type);
307 }
308
309 protected RuntimeException generateException() {
310 return new MirroredTypeException(type);
311 }
312
313 // Explicitly set all transient fields.
314 private void readObject(ObjectInputStream s)
315 throws IOException, ClassNotFoundException {
316 s.defaultReadObject();
317 type = null;
318 }
319 }
320
321
322 /**
323 * ExceptionProxy for MirroredTypesException.
324 * The toString, hashCode, and equals methods foward to the underlying
325 * types.
326 */
327 private static final class MirroredTypesExceptionProxy extends ExceptionProxy {
328 static final long serialVersionUID = 269;
329
330 private transient List<TypeMirror> types;
331 private final String typeStrings;
332
333 MirroredTypesExceptionProxy(List<TypeMirror> ts) {
334 types = ts;
335 typeStrings = ts.toString();
336 }
337
338 public String toString() {
339 return types.stream()
340 .map(t -> t.toString() + ".class")
341 .collect(Collectors.joining(", ", "{", "}"));
342 }
343
344 public int hashCode() {
345 return (types != null ? types : typeStrings).hashCode();
346 }
347
348 public boolean equals(Object obj) {
349 return types != null &&
350 obj instanceof MirroredTypesExceptionProxy &&
351 types.equals(
352 ((MirroredTypesExceptionProxy) obj).types);
353 }
354
355 protected RuntimeException generateException() {
356 return new MirroredTypesException(types);
357 }
358
359 // Explicitly set all transient fields.
360 private void readObject(ObjectInputStream s)
361 throws IOException, ClassNotFoundException {
362 s.defaultReadObject();
363 types = null;
364 }
365 }
366 }