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, boolean isDefault) {
93 int mod = getModifiers() & mask;
94
95 if (mod != 0 && !isDefault) {
96 sb.append(Modifier.toString(mod)).append(' ');
97 } else {
98 int access_mod = mod & Modifier.ACCESS_MODIFIERS;
99 if (access_mod != 0)
100 sb.append(Modifier.toString(access_mod)).append(' ');
101 if (isDefault)
102 sb.append("default ");
103 mod = (mod & ~Modifier.ACCESS_MODIFIERS);
104 if (mod != 0)
105 sb.append(Modifier.toString(mod)).append(' ');
106 }
107 }
108
109 String sharedToString(int modifierMask,
110 boolean isDefault,
111 Class<?>[] parameterTypes,
112 Class<?>[] exceptionTypes) {
113 try {
114 StringBuilder sb = new StringBuilder();
115
116 printModifiersIfNonzero(sb, modifierMask, isDefault);
117 specificToStringHeader(sb);
118
119 sb.append('(');
120 separateWithCommas(parameterTypes, sb);
121 sb.append(')');
122 if (exceptionTypes.length > 0) {
123 sb.append(" throws ");
124 separateWithCommas(exceptionTypes, sb);
125 }
126 return sb.toString();
127 } catch (Exception e) {
128 return "<" + e + ">";
129 }
130 }
131
132 /**
133 * Generate toString header information specific to a method or
134 * constructor.
135 */
136 abstract void specificToStringHeader(StringBuilder sb);
137
138 String sharedToGenericString(int modifierMask, boolean isDefault) {
139 try {
140 StringBuilder sb = new StringBuilder();
141
142 printModifiersIfNonzero(sb, modifierMask, isDefault);
143
144 TypeVariable<?>[] typeparms = getTypeParameters();
145 if (typeparms.length > 0) {
146 boolean first = true;
147 sb.append('<');
148 for(TypeVariable<?> typeparm: typeparms) {
149 if (!first)
150 sb.append(',');
151 // Class objects can't occur here; no need to test
152 // and call Class.getName().
153 sb.append(typeparm.toString());
154 first = false;
155 }
156 sb.append("> ");
157 }
158
159 specificToGenericStringHeader(sb);
160
161 sb.append('(');
162 Type[] params = getGenericParameterTypes();
163 for (int j = 0; j < params.length; j++) {
164 String param = (params[j] instanceof Class)?
165 Field.getTypeName((Class)params[j]):
166 (params[j].toString());
167 if (isVarArgs() && (j == params.length - 1)) // replace T[] with T...
168 param = param.replaceFirst("\\[\\]$", "...");
169 sb.append(param);
170 if (j < (params.length - 1))
171 sb.append(',');
172 }
173 sb.append(')');
174 Type[] exceptions = getGenericExceptionTypes();
175 if (exceptions.length > 0) {
176 sb.append(" throws ");
177 for (int k = 0; k < exceptions.length; k++) {
178 sb.append((exceptions[k] instanceof Class)?
179 ((Class)exceptions[k]).getName():
180 exceptions[k].toString());
181 if (k < (exceptions.length - 1))
182 sb.append(',');
183 }
184 }
185 return sb.toString();
186 } catch (Exception e) {
187 return "<" + e + ">";
188 }
189 }
190
191 /**
192 * Generate toGenericString header information specific to a
193 * method or constructor.
194 */
195 abstract void specificToGenericStringHeader(StringBuilder sb);
196
197 /**
198 * Returns the {@code Class} object representing the class or interface
199 * that declares the executable represented by this object.
200 */
201 public abstract Class<?> getDeclaringClass();
202
203 /**
204 * Returns the name of the executable represented by this object.
205 */
206 public abstract String getName();
207
208 /**
209 * Returns the Java language {@linkplain Modifier modifiers} for
210 * the executable represented by this object.
211 */
212 public abstract int getModifiers();
213
214 /**
215 * Returns an array of {@code TypeVariable} objects that represent the
216 * type variables declared by the generic declaration represented by this
217 * {@code GenericDeclaration} object, in declaration order. Returns an
218 * array of length 0 if the underlying generic declaration declares no type
219 * variables.
220 *
221 * @return an array of {@code TypeVariable} objects that represent
222 * the type variables declared by this generic declaration
223 * @throws GenericSignatureFormatError if the generic
224 * signature of this generic declaration does not conform to
225 * the format specified in
226 * <cite>The Java™ Virtual Machine Specification</cite>
227 */
228 public abstract TypeVariable<?>[] getTypeParameters();
229
230 /**
231 * Returns an array of {@code Class} objects that represent the formal
232 * parameter types, in declaration order, of the executable
233 * represented by this object. Returns an array of length
234 * 0 if the underlying executable takes no parameters.
235 *
236 * @return the parameter types for the executable this object
237 * represents
238 */
239 public abstract Class<?>[] getParameterTypes();
240
241 /**
242 * Returns the number of formal parameters (including any
243 * synthetic or synthesized parameters) for the executable
244 * represented by this object.
245 *
246 * @return The number of formal parameters for the executable this
247 * object represents
248 */
249 public int getParameterCount() {
250 throw new AbstractMethodError();
251 }
252
253 /**
254 * Returns an array of {@code Type} objects that represent the formal
255 * parameter types, in declaration order, of the executable represented by
256 * this object. Returns an array of length 0 if the
257 * underlying executable takes no parameters.
258 *
259 * <p>If a formal parameter type is a parameterized type,
260 * the {@code Type} object returned for it must accurately reflect
261 * the actual type parameters used in the source code.
262 *
263 * <p>If a formal parameter type is a type variable or a parameterized
264 * type, it is created. Otherwise, it is resolved.
265 *
266 * @return an array of {@code Type}s that represent the formal
267 * parameter types of the underlying executable, in declaration order
268 * @throws GenericSignatureFormatError
269 * if the generic method signature does not conform to the format
270 * specified in
271 * <cite>The Java™ Virtual Machine Specification</cite>
272 * @throws TypeNotPresentException if any of the parameter
273 * types of the underlying executable refers to a non-existent type
274 * declaration
275 * @throws MalformedParameterizedTypeException if any of
276 * the underlying executable's parameter types refer to a parameterized
277 * type that cannot be instantiated for any reason
278 */
279 public Type[] getGenericParameterTypes() {
280 if (hasGenericInformation())
281 return getGenericInfo().getParameterTypes();
282 else
283 return getParameterTypes();
284 }
285
286 /**
287 * Returns an array of {@code Parameter} objects that represent
288 * all the parameters to the underlying executable represented by
289 * this object. Returns an array of length 0 if the executable
290 * has no parameters.
291 *
292 * The parameters of the underlying executable do not necessarily
293 * have unique names, or names that are legal identifiers in the
294 * Java programming language (JLS 3.8).
295 *
296 * @return an array of {@code Parameter} objects representing all
297 * the parameters to the executable this object represents
298 */
299 public Parameter[] getParameters() {
300 // TODO: This may eventually need to be guarded by security
301 // mechanisms similar to those in Field, Method, etc.
302 //
303 // Need to copy the cached array to prevent users from messing
304 // with it. Since parameters are immutable, we can
305 // shallow-copy.
306 return privateGetParameters().clone();
307 }
308
309 private Parameter[] synthesizeAllParams() {
310 final int realparams = getParameterCount();
311 final Parameter[] out = new Parameter[realparams];
312 for (int i = 0; i < realparams; i++)
313 // TODO: is there a way to synthetically derive the
314 // modifiers? Probably not in the general case, since
315 // we'd have no way of knowing about them, but there
316 // may be specific cases.
317 out[i] = new Parameter("arg" + i, 0, this, i);
318 return out;
319 }
320
321 private Parameter[] privateGetParameters() {
322 // Use tmp to avoid multiple writes to a volatile.
323 Parameter[] tmp = parameters;
324
325 if (tmp == null) {
326
327 // Otherwise, go to the JVM to get them
328 tmp = getParameters0();
329
330 // If we get back nothing, then synthesize parameters
331 if (tmp == null)
332 tmp = synthesizeAllParams();
333
334 parameters = tmp;
335 }
336
337 return tmp;
338 }
339
340 private transient volatile Parameter[] parameters;
341
342 private native Parameter[] getParameters0();
343
344 /**
345 * Returns an array of {@code Class} objects that represent the
346 * types of exceptions declared to be thrown by the underlying
347 * executable represented by this object. Returns an array of
348 * length 0 if the executable declares no exceptions in its {@code
349 * throws} clause.
350 *
351 * @return the exception types declared as being thrown by the
352 * executable this object represents
353 */
354 public abstract Class<?>[] getExceptionTypes();
355
356 /**
357 * Returns an array of {@code Type} objects that represent the
358 * exceptions declared to be thrown by this executable object.
359 * Returns an array of length 0 if the underlying executable declares
360 * no exceptions in its {@code throws} clause.
361 *
362 * <p>If an exception type is a type variable or a parameterized
363 * type, it is created. Otherwise, it is resolved.
364 *
365 * @return an array of Types that represent the exception types
366 * thrown by the underlying executable
367 * @throws GenericSignatureFormatError
368 * if the generic method signature does not conform to the format
369 * specified in
370 * <cite>The Java™ Virtual Machine Specification</cite>
371 * @throws TypeNotPresentException if the underlying executable's
372 * {@code throws} clause refers to a non-existent type declaration
373 * @throws MalformedParameterizedTypeException if
374 * the underlying executable's {@code throws} clause refers to a
375 * parameterized type that cannot be instantiated for any reason
376 */
377 public Type[] getGenericExceptionTypes() {
378 Type[] result;
379 if (hasGenericInformation() &&
380 ((result = getGenericInfo().getExceptionTypes()).length > 0))
381 return result;
382 else
383 return getExceptionTypes();
384 }
385
386 /**
387 * Returns a string describing this {@code Executable}, including
388 * any type parameters.
389 */
390 public abstract String toGenericString();
391
392 /**
393 * Returns {@code true} if this executable was declared to take a
394 * variable number of arguments; returns {@code false} otherwise.
395 *
396 * @return {@code true} if an only if this executable was declared
397 * to take a variable number of arguments.
398 */
399 public boolean isVarArgs() {
400 return (getModifiers() & Modifier.VARARGS) != 0;
401 }
402
403 /**
404 * Returns {@code true} if this executable is a synthetic
405 * construct; returns {@code false} otherwise.
406 *
407 * @return true if and only if this executable is a synthetic
408 * construct as defined by
409 * <cite>The Java™ Language Specification</cite>.
410 * @jls 13.1 The Form of a Binary
411 */
412 public boolean isSynthetic() {
413 return Modifier.isSynthetic(getModifiers());
414 }
415
416 /**
417 * Returns an array of arrays that represent the annotations on
418 * the formal parameters, in declaration order, of the executable
419 * represented by this object. (Returns an array of length zero if
420 * the underlying executable is parameterless. If the executable has
421 * one or more parameters, a nested array of length zero is
422 * returned for each parameter with no annotations.) The
423 * annotation objects contained in the returned arrays are
424 * serializable. The caller of this method is free to modify the
425 * returned arrays; it will have no effect on the arrays returned
426 * to other callers.
427 *
428 * @return an array of arrays that represent the annotations on the formal
429 * parameters, in declaration order, of the executable represented by this
430 * object
431 */
432 public abstract Annotation[][] getParameterAnnotations();
433
434 Annotation[][] sharedGetParameterAnnotations(Class<?>[] parameterTypes,
435 byte[] parameterAnnotations) {
436 int numParameters = parameterTypes.length;
437 if (parameterAnnotations == null)
438 return new Annotation[numParameters][0];
439
440 Annotation[][] result = parseParameterAnnotations(parameterAnnotations);
441
442 if (result.length != numParameters)
443 handleParameterNumberMismatch(result.length, numParameters);
444 return result;
445 }
446
447 abstract void handleParameterNumberMismatch(int resultLength, int numParameters);
448
449 /**
450 * {@inheritDoc}
451 * @throws NullPointerException {@inheritDoc}
452 */
453 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
454 Objects.requireNonNull(annotationClass);
455 return annotationClass.cast(declaredAnnotations().get(annotationClass));
456 }
457
458 /**
459 * {@inheritDoc}
460 * @throws NullPointerException {@inheritDoc}
461 * @since 1.8
462 */
463 @Override
464 public <T extends Annotation> T[] getAnnotationsByType(Class<T> annotationClass) {
465 Objects.requireNonNull(annotationClass);
466
467 return AnnotationSupport.getMultipleAnnotations(declaredAnnotations(), annotationClass);
468 }
469
470 /**
471 * {@inheritDoc}
472 */
473 public Annotation[] getDeclaredAnnotations() {
474 return AnnotationParser.toArray(declaredAnnotations());
475 }
476
477 private transient Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
478
479 private synchronized Map<Class<? extends Annotation>, Annotation> declaredAnnotations() {
480 if (declaredAnnotations == null) {
481 declaredAnnotations = AnnotationParser.parseAnnotations(
482 getAnnotationBytes(),
483 sun.misc.SharedSecrets.getJavaLangAccess().
484 getConstantPool(getDeclaringClass()),
485 getDeclaringClass());
486 }
487 return declaredAnnotations;
488 }
489
490 /**
491 * Returns an AnnotatedType object that represents the potentially
492 * annotated return type of the method/constructor represented by this
493 * Executable.
494 *
495 * If this Executable represents a constructor, the AnnotatedType object
496 * represents the type of the constructed object.
497 *
498 * If this Executable represents a method, the AnnotatedType object
499 * represents the use of a type to specify the return type of the method.
500 *
501 * @since 1.8
502 */
503 public abstract AnnotatedType getAnnotatedReturnType();
504
505 /* Helper for subclasses of Executable.
506 *
507 * Returns an AnnotatedType object that represents the use of a type to
508 * specify the return type of the method/constructor represented by this
509 * Executable.
510 *
511 * @since 1.8
512 */
513 AnnotatedType getAnnotatedReturnType0(Type returnType) {
514 return TypeAnnotationParser.buildAnnotatedType(getTypeAnnotationBytes(),
515 sun.misc.SharedSecrets.getJavaLangAccess().
516 getConstantPool(getDeclaringClass()),
517 this,
518 getDeclaringClass(),
519 returnType,
520 TypeAnnotation.TypeAnnotationTarget.METHOD_RETURN_TYPE);
521 }
522
523 /**
524 * Returns an AnnotatedType object that represents the use of a type to
525 * specify the receiver type of the method/constructor represented by this
526 * Executable. The receiver type of a method/constructor is available only
527 * if the method/constructor declares a formal parameter called 'this'.
528 *
529 * Returns null if this Executable represents a constructor or instance
530 * method that either declares no formal parameter called 'this', or
531 * declares a formal parameter called 'this' with no annotations on its
532 * type.
533 *
534 * Returns null if this Executable represents a static method.
535 *
536 * @since 1.8
537 */
538 public AnnotatedType getAnnotatedReceiverType() {
539 return TypeAnnotationParser.buildAnnotatedType(getTypeAnnotationBytes(),
540 sun.misc.SharedSecrets.getJavaLangAccess().
541 getConstantPool(getDeclaringClass()),
542 this,
543 getDeclaringClass(),
544 getDeclaringClass(),
545 TypeAnnotation.TypeAnnotationTarget.METHOD_RECEIVER_TYPE);
546 }
547
548 /**
549 * Returns an array of AnnotatedType objects that represent the use of
550 * types to specify formal parameter types of the method/constructor
551 * represented by this Executable. The order of the objects in the array
552 * corresponds to the order of the formal parameter types in the
553 * declaration of the method/constructor.
554 *
555 * Returns an array of length 0 if the method/constructor declares no
556 * parameters.
557 *
558 * @since 1.8
559 */
560 public AnnotatedType[] getAnnotatedParameterTypes() {
561 throw new UnsupportedOperationException("Not yet");
562 }
563
564 /**
565 * Returns an array of AnnotatedType objects that represent the use of
566 * types to specify the declared exceptions of the method/constructor
567 * represented by this Executable. The order of the objects in the array
568 * corresponds to the order of the exception types in the declaration of
569 * the method/constructor.
570 *
571 * Returns an array of length 0 if the method/constructor declares no
572 * exceptions.
573 *
574 * @since 1.8
575 */
576 public AnnotatedType[] getAnnotatedExceptionTypes() {
577 return TypeAnnotationParser.buildAnnotatedTypes(getTypeAnnotationBytes(),
578 sun.misc.SharedSecrets.getJavaLangAccess().
579 getConstantPool(getDeclaringClass()),
580 this,
581 getDeclaringClass(),
582 getGenericExceptionTypes(),
583 TypeAnnotation.TypeAnnotationTarget.THROWS);
584 }
585
586 }