1 /*
2 * Copyright (c) 2012, 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 java.lang.reflect;
27
28 import java.lang.annotation.*;
29 import java.util.Map;
30 import java.util.Objects;
31 import sun.reflect.annotation.AnnotationParser;
32 import sun.reflect.annotation.AnnotationSupport;
33 import sun.reflect.annotation.TypeAnnotationParser;
34 import sun.reflect.annotation.TypeAnnotation;
35 import sun.reflect.generics.repository.ConstructorRepository;
36
37 /**
38 * A shared superclass for the common functionality of {@link Method}
39 * and {@link Constructor}.
40 *
41 * @since 1.8
42 */
43 public abstract class Executable extends AccessibleObject
44 implements Member, GenericDeclaration {
45 /*
46 * Only grant package-visibility to the constructor.
47 */
48 Executable() {}
49
50 /**
51 * Accessor method to allow code sharing
52 */
53 abstract byte[] getAnnotationBytes();
54 abstract byte[] getTypeAnnotationBytes();
55
56 /**
57 * Does the Executable have generic information.
58 */
59 abstract boolean hasGenericInformation();
60
61 abstract ConstructorRepository getGenericInfo();
62
63 boolean equalParamTypes(Class<?>[] params1, Class<?>[] params2) {
64 /* Avoid unnecessary cloning */
65 if (params1.length == params2.length) {
66 for (int i = 0; i < params1.length; i++) {
67 if (params1[i] != params2[i])
68 return false;
69 }
70 return true;
71 }
72 return false;
73 }
74
75 Annotation[][] parseParameterAnnotations(byte[] parameterAnnotations) {
76 return AnnotationParser.parseParameterAnnotations(
77 parameterAnnotations,
78 sun.misc.SharedSecrets.getJavaLangAccess().
79 getConstantPool(getDeclaringClass()),
80 getDeclaringClass());
81 }
82
83 void separateWithCommas(Class<?>[] types, StringBuilder sb) {
84 for (int j = 0; j < types.length; j++) {
85 sb.append(Field.getTypeName(types[j]));
86 if (j < (types.length - 1))
87 sb.append(",");
88 }
89
90 }
91
92 void printModifiersIfNonzero(StringBuilder sb, int mask) {
93 int mod = getModifiers() & mask;
94 if (mod != 0) {
95 sb.append(Modifier.toString(mod)).append(' ');
96 }
97 }
98
99 String sharedToString(int modifierMask,
100 Class<?>[] parameterTypes,
101 Class<?>[] exceptionTypes) {
102 try {
103 StringBuilder sb = new StringBuilder();
104
105 printModifiersIfNonzero(sb, modifierMask);
106 specificToStringHeader(sb);
107
108 sb.append('(');
109 separateWithCommas(parameterTypes, sb);
110 sb.append(')');
111 if (exceptionTypes.length > 0) {
112 sb.append(" throws ");
113 separateWithCommas(exceptionTypes, sb);
114 }
115 return sb.toString();
116 } catch (Exception e) {
117 return "<" + e + ">";
118 }
119 }
120
121 /**
122 * Generate toString header information specific to a method or
123 * constructor.
124 */
125 abstract void specificToStringHeader(StringBuilder sb);
126
127 String sharedToGenericString(int modifierMask) {
128 try {
129 StringBuilder sb = new StringBuilder();
130
131 printModifiersIfNonzero(sb, modifierMask);
132
133 TypeVariable<?>[] typeparms = getTypeParameters();
134 if (typeparms.length > 0) {
135 boolean first = true;
136 sb.append('<');
137 for(TypeVariable<?> typeparm: typeparms) {
138 if (!first)
139 sb.append(',');
140 // Class objects can't occur here; no need to test
141 // and call Class.getName().
142 sb.append(typeparm.toString());
143 first = false;
144 }
145 sb.append("> ");
146 }
147
148 specificToGenericStringHeader(sb);
149
150 sb.append('(');
151 Type[] params = getGenericParameterTypes();
152 for (int j = 0; j < params.length; j++) {
153 String param = (params[j] instanceof Class)?
154 Field.getTypeName((Class)params[j]):
155 (params[j].toString());
156 if (isVarArgs() && (j == params.length - 1)) // replace T[] with T...
157 param = param.replaceFirst("\\[\\]$", "...");
158 sb.append(param);
159 if (j < (params.length - 1))
160 sb.append(',');
161 }
162 sb.append(')');
163 Type[] exceptions = getGenericExceptionTypes();
164 if (exceptions.length > 0) {
165 sb.append(" throws ");
166 for (int k = 0; k < exceptions.length; k++) {
167 sb.append((exceptions[k] instanceof Class)?
168 ((Class)exceptions[k]).getName():
169 exceptions[k].toString());
170 if (k < (exceptions.length - 1))
171 sb.append(',');
172 }
173 }
174 return sb.toString();
175 } catch (Exception e) {
176 return "<" + e + ">";
177 }
178 }
179
180 /**
181 * Generate toGenericString header information specific to a
182 * method or constructor.
183 */
184 abstract void specificToGenericStringHeader(StringBuilder sb);
185
186 /**
187 * Returns the {@code Class} object representing the class or interface
188 * that declares the executable represented by this object.
189 */
190 public abstract Class<?> getDeclaringClass();
191
192 /**
193 * Returns the name of the executable represented by this object.
194 */
195 public abstract String getName();
196
197 /**
198 * Returns the Java language {@linkplain Modifier modifiers} for
199 * the executable represented by this object.
200 */
201 public abstract int getModifiers();
202
203 /**
204 * Returns an array of {@code TypeVariable} objects that represent the
205 * type variables declared by the generic declaration represented by this
206 * {@code GenericDeclaration} object, in declaration order. Returns an
207 * array of length 0 if the underlying generic declaration declares no type
208 * variables.
209 *
210 * @return an array of {@code TypeVariable} objects that represent
211 * the type variables declared by this generic declaration
212 * @throws GenericSignatureFormatError if the generic
213 * signature of this generic declaration does not conform to
214 * the format specified in
215 * <cite>The Java™ Virtual Machine Specification</cite>
216 */
217 public abstract TypeVariable<?>[] getTypeParameters();
218
219 /**
220 * Returns an array of {@code Class} objects that represent the formal
221 * parameter types, in declaration order, of the executable
222 * represented by this object. Returns an array of length
223 * 0 if the underlying executable takes no parameters.
224 *
225 * @return the parameter types for the executable this object
226 * represents
227 */
228 public abstract Class<?>[] getParameterTypes();
229
230 /**
231 * Returns the number of formal parameters (including any
232 * synthetic or synthesized parameters) for the executable
233 * represented by this object.
234 *
235 * @return The number of formal parameters for the executable this
236 * object represents
237 */
238 public int getParameterCount() {
239 throw new AbstractMethodError();
240 }
241
242 /**
243 * Returns an array of {@code Type} objects that represent the formal
244 * parameter types, in declaration order, of the executable represented by
245 * this object. Returns an array of length 0 if the
246 * underlying executable takes no parameters.
247 *
248 * <p>If a formal parameter type is a parameterized type,
249 * the {@code Type} object returned for it must accurately reflect
250 * the actual type parameters used in the source code.
251 *
252 * <p>If a formal parameter type is a type variable or a parameterized
253 * type, it is created. Otherwise, it is resolved.
254 *
255 * @return an array of {@code Type}s that represent the formal
256 * parameter types of the underlying executable, in declaration order
257 * @throws GenericSignatureFormatError
258 * if the generic method signature does not conform to the format
259 * specified in
260 * <cite>The Java™ Virtual Machine Specification</cite>
261 * @throws TypeNotPresentException if any of the parameter
262 * types of the underlying executable refers to a non-existent type
263 * declaration
264 * @throws MalformedParameterizedTypeException if any of
265 * the underlying executable's parameter types refer to a parameterized
266 * type that cannot be instantiated for any reason
267 */
268 public Type[] getGenericParameterTypes() {
269 if (hasGenericInformation())
270 return getGenericInfo().getParameterTypes();
271 else
272 return getParameterTypes();
273 }
274
275 /**
276 * Returns an array of {@code Parameter} objects that represent
277 * all the parameters to the underlying executable represented by
278 * this object. Returns an array of length 0 if the executable
279 * has no parameters.
280 *
281 * The parameters of the underlying executable do not necessarily
282 * have unique names, or names that are legal identifiers in the
283 * Java programming language (JLS 3.8).
284 *
285 * @return an array of {@code Parameter} objects representing all
286 * the parameters to the executable this object represents
287 */
288 public Parameter[] getParameters() {
289 // TODO: This may eventually need to be guarded by security
290 // mechanisms similar to those in Field, Method, etc.
291 //
292 // Need to copy the cached array to prevent users from messing
293 // with it. Since parameters are immutable, we can
294 // shallow-copy.
295 return privateGetParameters().clone();
296 }
297
298 private Parameter[] synthesizeAllParams() {
299 final int realparams = getParameterCount();
300 final Parameter[] out = new Parameter[realparams];
301 for (int i = 0; i < realparams; i++)
302 // TODO: is there a way to synthetically derive the
303 // modifiers? Probably not in the general case, since
304 // we'd have no way of knowing about them, but there
305 // may be specific cases.
306 out[i] = new Parameter("arg" + i, 0, this, i);
307 return out;
308 }
309
310 private Parameter[] privateGetParameters() {
311 // Use tmp to avoid multiple writes to a volatile.
312 Parameter[] tmp = parameters;
313
314 if (tmp == null) {
315
316 // Otherwise, go to the JVM to get them
317 tmp = getParameters0();
318
319 // If we get back nothing, then synthesize parameters
320 if (tmp == null)
321 tmp = synthesizeAllParams();
322
323 parameters = tmp;
324 }
325
326 return tmp;
327 }
328
329 private transient volatile Parameter[] parameters;
330
331 private native Parameter[] getParameters0();
332
333 /**
334 * Returns an array of {@code Class} objects that represent the
335 * types of exceptions declared to be thrown by the underlying
336 * executable represented by this object. Returns an array of
337 * length 0 if the executable declares no exceptions in its {@code
338 * throws} clause.
339 *
340 * @return the exception types declared as being thrown by the
341 * executable this object represents
342 */
343 public abstract Class<?>[] getExceptionTypes();
344
345 /**
346 * Returns an array of {@code Type} objects that represent the
347 * exceptions declared to be thrown by this executable object.
348 * Returns an array of length 0 if the underlying executable declares
349 * no exceptions in its {@code throws} clause.
350 *
351 * <p>If an exception type is a type variable or a parameterized
352 * type, it is created. Otherwise, it is resolved.
353 *
354 * @return an array of Types that represent the exception types
355 * thrown by the underlying executable
356 * @throws GenericSignatureFormatError
357 * if the generic method signature does not conform to the format
358 * specified in
359 * <cite>The Java™ Virtual Machine Specification</cite>
360 * @throws TypeNotPresentException if the underlying executable's
361 * {@code throws} clause refers to a non-existent type declaration
362 * @throws MalformedParameterizedTypeException if
363 * the underlying executable's {@code throws} clause refers to a
364 * parameterized type that cannot be instantiated for any reason
365 */
366 public Type[] getGenericExceptionTypes() {
367 Type[] result;
368 if (hasGenericInformation() &&
369 ((result = getGenericInfo().getExceptionTypes()).length > 0))
370 return result;
371 else
372 return getExceptionTypes();
373 }
374
375 /**
376 * Returns a string describing this {@code Executable}, including
377 * any type parameters.
378 */
379 public abstract String toGenericString();
380
381 /**
382 * Returns {@code true} if this executable was declared to take a
383 * variable number of arguments; returns {@code false} otherwise.
384 *
385 * @return {@code true} if an only if this executable was declared
386 * to take a variable number of arguments.
387 */
388 public boolean isVarArgs() {
389 return (getModifiers() & Modifier.VARARGS) != 0;
390 }
391
392 /**
393 * Returns {@code true} if this executable is a synthetic
394 * construct; returns {@code false} otherwise.
395 *
396 * @return true if and only if this executable is a synthetic
397 * construct as defined by
398 * <cite>The Java™ Language Specification</cite>.
399 * @jls 13.1 The Form of a Binary
400 */
401 public boolean isSynthetic() {
402 return Modifier.isSynthetic(getModifiers());
403 }
404
405 /**
406 * Returns an array of arrays that represent the annotations on
407 * the formal parameters, in declaration order, of the executable
408 * represented by this object. (Returns an array of length zero if
409 * the underlying executable is parameterless. If the executable has
410 * one or more parameters, a nested array of length zero is
411 * returned for each parameter with no annotations.) The
412 * annotation objects contained in the returned arrays are
413 * serializable. The caller of this method is free to modify the
414 * returned arrays; it will have no effect on the arrays returned
415 * to other callers.
416 *
417 * @return an array of arrays that represent the annotations on the formal
418 * parameters, in declaration order, of the executable represented by this
419 * object
420 */
421 public abstract Annotation[][] getParameterAnnotations();
422
423 Annotation[][] sharedGetParameterAnnotations(Class<?>[] parameterTypes,
424 byte[] parameterAnnotations) {
425 int numParameters = parameterTypes.length;
426 if (parameterAnnotations == null)
427 return new Annotation[numParameters][0];
428
429 Annotation[][] result = parseParameterAnnotations(parameterAnnotations);
430
431 if (result.length != numParameters)
432 handleParameterNumberMismatch(result.length, numParameters);
433 return result;
434 }
435
436 abstract void handleParameterNumberMismatch(int resultLength, int numParameters);
437
438 /**
439 * {@inheritDoc}
440 * @throws NullPointerException {@inheritDoc}
441 */
442 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
443 Objects.requireNonNull(annotationClass);
444 return annotationClass.cast(declaredAnnotations().get(annotationClass));
445 }
446
447 /**
448 * {@inheritDoc}
449 * @throws NullPointerException {@inheritDoc}
450 * @since 1.8
451 */
452 @Override
453 public <T extends Annotation> T[] getAnnotationsByType(Class<T> annotationClass) {
454 Objects.requireNonNull(annotationClass);
455
456 return AnnotationSupport.getMultipleAnnotations(declaredAnnotations(), annotationClass);
457 }
458
459 /**
460 * {@inheritDoc}
461 */
462 public Annotation[] getDeclaredAnnotations() {
463 return AnnotationParser.toArray(declaredAnnotations());
464 }
465
466 private transient Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
467
468 private synchronized Map<Class<? extends Annotation>, Annotation> declaredAnnotations() {
469 if (declaredAnnotations == null) {
470 declaredAnnotations = AnnotationParser.parseAnnotations(
471 getAnnotationBytes(),
472 sun.misc.SharedSecrets.getJavaLangAccess().
473 getConstantPool(getDeclaringClass()),
474 getDeclaringClass());
475 }
476 return declaredAnnotations;
477 }
478
479 /**
480 * Returns an AnnotatedType object that represents the potentially
481 * annotated return type of the method/constructor represented by this
482 * Executable.
483 *
484 * If this Executable represents a constructor, the AnnotatedType object
485 * represents the type of the constructed object.
486 *
487 * If this Executable represents a method, the AnnotatedType object
488 * represents the use of a type to specify the return type of the method.
489 *
490 * @since 1.8
491 */
492 public abstract AnnotatedType getAnnotatedReturnType();
493
494 /* Helper for subclasses of Executable.
495 *
496 * Returns an AnnotatedType object that represents the use of a type to
497 * specify the return type of the method/constructor represented by this
498 * Executable.
499 *
500 * @since 1.8
501 */
502 AnnotatedType getAnnotatedReturnType0(Type returnType) {
503 return TypeAnnotationParser.buildAnnotatedType(getTypeAnnotationBytes(),
504 sun.misc.SharedSecrets.getJavaLangAccess().
505 getConstantPool(getDeclaringClass()),
506 this,
507 getDeclaringClass(),
508 returnType,
509 TypeAnnotation.TypeAnnotationTarget.METHOD_RETURN_TYPE);
510 }
511
512 /**
513 * Returns an AnnotatedType object that represents the use of a type to
514 * specify the receiver type of the method/constructor represented by this
515 * Executable. The receiver type of a method/constructor is available only
516 * if the method/constructor declares a formal parameter called 'this'.
517 *
518 * Returns null if this Executable represents a constructor or instance
519 * method that either declares no formal parameter called 'this', or
520 * declares a formal parameter called 'this' with no annotations on its
521 * type.
522 *
523 * Returns null if this Executable represents a static method.
524 *
525 * @since 1.8
526 */
527 public AnnotatedType getAnnotatedReceiverType() {
528 return TypeAnnotationParser.buildAnnotatedType(getTypeAnnotationBytes(),
529 sun.misc.SharedSecrets.getJavaLangAccess().
530 getConstantPool(getDeclaringClass()),
531 this,
532 getDeclaringClass(),
533 getDeclaringClass(),
534 TypeAnnotation.TypeAnnotationTarget.METHOD_RECEIVER_TYPE);
535 }
536
537 /**
538 * Returns an array of AnnotatedType objects that represent the use of
539 * types to specify formal parameter types of the method/constructor
540 * represented by this Executable. The order of the objects in the array
541 * corresponds to the order of the formal parameter types in the
542 * declaration of the method/constructor.
543 *
544 * Returns an array of length 0 if the method/constructor declares no
545 * parameters.
546 *
547 * @since 1.8
548 */
549 public AnnotatedType[] getAnnotatedParameterTypes() {
550 throw new UnsupportedOperationException("Not yet");
551 }
552
553 /**
554 * Returns an array of AnnotatedType objects that represent the use of
555 * types to specify the declared exceptions of the method/constructor
556 * represented by this Executable. The order of the objects in the array
557 * corresponds to the order of the exception types in the declaration of
558 * the method/constructor.
559 *
560 * Returns an array of length 0 if the method/constructor declares no
561 * exceptions.
562 *
563 * @since 1.8
564 */
565 public AnnotatedType[] getAnnotatedExceptionTypes() {
566 return TypeAnnotationParser.buildAnnotatedTypes(getTypeAnnotationBytes(),
567 sun.misc.SharedSecrets.getJavaLangAccess().
568 getConstantPool(getDeclaringClass()),
569 this,
570 getDeclaringClass(),
571 getGenericExceptionTypes(),
572 TypeAnnotation.TypeAnnotationTarget.THROWS);
573 }
574
575 }