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(types[j].getTypeName());
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].getTypeName();
165 if (isVarArgs() && (j == params.length - 1)) // replace T[] with T...
166 param = param.replaceFirst("\\[\\]$", "...");
167 sb.append(param);
168 if (j < (params.length - 1))
169 sb.append(',');
170 }
171 sb.append(')');
172 Type[] exceptions = getGenericExceptionTypes();
173 if (exceptions.length > 0) {
174 sb.append(" throws ");
175 for (int k = 0; k < exceptions.length; k++) {
176 sb.append((exceptions[k] instanceof Class)?
177 ((Class)exceptions[k]).getName():
178 exceptions[k].toString());
179 if (k < (exceptions.length - 1))
180 sb.append(',');
181 }
182 }
183 return sb.toString();
184 } catch (Exception e) {
185 return "<" + e + ">";
186 }
187 }
188
189 /**
190 * Generate toGenericString header information specific to a
191 * method or constructor.
192 */
193 abstract void specificToGenericStringHeader(StringBuilder sb);
194
195 /**
196 * Returns the {@code Class} object representing the class or interface
197 * that declares the executable represented by this object.
198 */
199 public abstract Class<?> getDeclaringClass();
200
201 /**
202 * Returns the name of the executable represented by this object.
203 */
204 public abstract String getName();
205
206 /**
207 * Returns the Java language {@linkplain Modifier modifiers} for
208 * the executable represented by this object.
209 */
210 public abstract int getModifiers();
211
212 /**
213 * Returns an array of {@code TypeVariable} objects that represent the
214 * type variables declared by the generic declaration represented by this
215 * {@code GenericDeclaration} object, in declaration order. Returns an
216 * array of length 0 if the underlying generic declaration declares no type
217 * variables.
218 *
219 * @return an array of {@code TypeVariable} objects that represent
220 * the type variables declared by this generic declaration
221 * @throws GenericSignatureFormatError if the generic
222 * signature of this generic declaration does not conform to
223 * the format specified in
224 * <cite>The Java™ Virtual Machine Specification</cite>
225 */
226 public abstract TypeVariable<?>[] getTypeParameters();
227
228 /**
229 * Returns an array of {@code Class} objects that represent the formal
230 * parameter types, in declaration order, of the executable
231 * represented by this object. Returns an array of length
232 * 0 if the underlying executable takes no parameters.
233 *
234 * @return the parameter types for the executable this object
235 * represents
236 */
237 public abstract Class<?>[] getParameterTypes();
238
239 /**
240 * Returns the number of formal parameters (whether explicitly
241 * declared or implicitly declared or neither) for the executable
242 * represented by this object.
243 *
244 * @return The number of formal parameters for the executable this
245 * object represents
246 */
247 public int getParameterCount() {
248 throw new AbstractMethodError();
249 }
250
251 /**
252 * Returns an array of {@code Type} objects that represent the formal
253 * parameter types, in declaration order, of the executable represented by
254 * this object. Returns an array of length 0 if the
255 * underlying executable takes no parameters.
256 *
257 * <p>If a formal parameter type is a parameterized type,
258 * the {@code Type} object returned for it must accurately reflect
259 * the actual type parameters used in the source code.
260 *
261 * <p>If a formal parameter type is a type variable or a parameterized
262 * type, it is created. Otherwise, it is resolved.
263 *
264 * @return an array of {@code Type}s that represent the formal
265 * parameter types of the underlying executable, in declaration order
266 * @throws GenericSignatureFormatError
267 * if the generic method signature does not conform to the format
268 * specified in
269 * <cite>The Java™ Virtual Machine Specification</cite>
270 * @throws TypeNotPresentException if any of the parameter
271 * types of the underlying executable refers to a non-existent type
272 * declaration
273 * @throws MalformedParameterizedTypeException if any of
274 * the underlying executable's parameter types refer to a parameterized
275 * type that cannot be instantiated for any reason
276 */
277 public Type[] getGenericParameterTypes() {
278 if (hasGenericInformation())
279 return getGenericInfo().getParameterTypes();
280 else
281 return getParameterTypes();
282 }
283
284 /**
285 * Returns an array of {@code Parameter} objects that represent
286 * all the parameters to the underlying executable represented by
287 * this object. Returns an array of length 0 if the executable
288 * has no parameters.
289 *
290 * The parameters of the underlying executable do not necessarily
291 * have unique names, or names that are legal identifiers in the
292 * Java programming language (JLS 3.8).
293 *
294 * @return an array of {@code Parameter} objects representing all
295 * the parameters to the executable this object represents
296 */
297 public Parameter[] getParameters() {
298 // TODO: This may eventually need to be guarded by security
299 // mechanisms similar to those in Field, Method, etc.
300 //
301 // Need to copy the cached array to prevent users from messing
302 // with it. Since parameters are immutable, we can
303 // shallow-copy.
304 return privateGetParameters().clone();
305 }
306
307 private Parameter[] synthesizeAllParams() {
308 final int realparams = getParameterCount();
309 final Parameter[] out = new Parameter[realparams];
310 for (int i = 0; i < realparams; i++)
311 // TODO: is there a way to synthetically derive the
312 // modifiers? Probably not in the general case, since
313 // we'd have no way of knowing about them, but there
314 // may be specific cases.
315 out[i] = new Parameter("arg" + i, 0, this, i);
316 return out;
317 }
318
319 private Parameter[] privateGetParameters() {
320 // Use tmp to avoid multiple writes to a volatile.
321 Parameter[] tmp = parameters;
322
323 if (tmp == null) {
324
325 // Otherwise, go to the JVM to get them
326 tmp = getParameters0();
327
328 // If we get back nothing, then synthesize parameters
329 if (tmp == null) {
330 hasRealParameterData = false;
331 tmp = synthesizeAllParams();
332 } else {
333 hasRealParameterData = true;
334 }
335
336 parameters = tmp;
337 }
338
339 return tmp;
340 }
341
342 boolean hasRealParameterData() {
343 // If this somehow gets called before parameters gets
344 // initialized, force it into existence.
345 if (parameters == null)
346 privateGetParameters();
347
348 return hasRealParameterData;
349 }
350
351 private boolean hasRealParameterData;
352 private transient volatile Parameter[] parameters;
353
354 private native Parameter[] getParameters0();
355
356 /**
357 * Returns an array of {@code Class} objects that represent the
358 * types of exceptions declared to be thrown by the underlying
359 * executable represented by this object. Returns an array of
360 * length 0 if the executable declares no exceptions in its {@code
361 * throws} clause.
362 *
363 * @return the exception types declared as being thrown by the
364 * executable this object represents
365 */
366 public abstract Class<?>[] getExceptionTypes();
367
368 /**
369 * Returns an array of {@code Type} objects that represent the
370 * exceptions declared to be thrown by this executable object.
371 * Returns an array of length 0 if the underlying executable declares
372 * no exceptions in its {@code throws} clause.
373 *
374 * <p>If an exception type is a type variable or a parameterized
375 * type, it is created. Otherwise, it is resolved.
376 *
377 * @return an array of Types that represent the exception types
378 * thrown by the underlying executable
379 * @throws GenericSignatureFormatError
380 * if the generic method signature does not conform to the format
381 * specified in
382 * <cite>The Java™ Virtual Machine Specification</cite>
383 * @throws TypeNotPresentException if the underlying executable's
384 * {@code throws} clause refers to a non-existent type declaration
385 * @throws MalformedParameterizedTypeException if
386 * the underlying executable's {@code throws} clause refers to a
387 * parameterized type that cannot be instantiated for any reason
388 */
389 public Type[] getGenericExceptionTypes() {
390 Type[] result;
391 if (hasGenericInformation() &&
392 ((result = getGenericInfo().getExceptionTypes()).length > 0))
393 return result;
394 else
395 return getExceptionTypes();
396 }
397
398 /**
399 * Returns a string describing this {@code Executable}, including
400 * any type parameters.
401 */
402 public abstract String toGenericString();
403
404 /**
405 * Returns {@code true} if this executable was declared to take a
406 * variable number of arguments; returns {@code false} otherwise.
407 *
408 * @return {@code true} if an only if this executable was declared
409 * to take a variable number of arguments.
410 */
411 public boolean isVarArgs() {
412 return (getModifiers() & Modifier.VARARGS) != 0;
413 }
414
415 /**
416 * Returns {@code true} if this executable is a synthetic
417 * construct; returns {@code false} otherwise.
418 *
419 * @return true if and only if this executable is a synthetic
420 * construct as defined by
421 * <cite>The Java™ Language Specification</cite>.
422 * @jls 13.1 The Form of a Binary
423 */
424 public boolean isSynthetic() {
425 return Modifier.isSynthetic(getModifiers());
426 }
427
428 /**
429 * Returns an array of arrays that represent the annotations on
430 * the formal parameters, in declaration order, of the executable
431 * represented by this object. (Returns an array of length zero if
432 * the underlying executable is parameterless. If the executable has
433 * one or more parameters, a nested array of length zero is
434 * returned for each parameter with no annotations.) The
435 * annotation objects contained in the returned arrays are
436 * serializable. The caller of this method is free to modify the
437 * returned arrays; it will have no effect on the arrays returned
438 * to other callers.
439 *
440 * @return an array of arrays that represent the annotations on the formal
441 * parameters, in declaration order, of the executable represented by this
442 * object
443 */
444 public abstract Annotation[][] getParameterAnnotations();
445
446 Annotation[][] sharedGetParameterAnnotations(Class<?>[] parameterTypes,
447 byte[] parameterAnnotations) {
448 int numParameters = parameterTypes.length;
449 if (parameterAnnotations == null)
450 return new Annotation[numParameters][0];
451
452 Annotation[][] result = parseParameterAnnotations(parameterAnnotations);
453
454 if (result.length != numParameters)
455 handleParameterNumberMismatch(result.length, numParameters);
456 return result;
457 }
458
459 abstract void handleParameterNumberMismatch(int resultLength, int numParameters);
460
461 /**
462 * {@inheritDoc}
463 * @throws NullPointerException {@inheritDoc}
464 */
465 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
466 Objects.requireNonNull(annotationClass);
467 return annotationClass.cast(declaredAnnotations().get(annotationClass));
468 }
469
470 /**
471 * {@inheritDoc}
472 * @throws NullPointerException {@inheritDoc}
473 * @since 1.8
474 */
475 @Override
476 public <T extends Annotation> T[] getAnnotationsByType(Class<T> annotationClass) {
477 Objects.requireNonNull(annotationClass);
478
479 return AnnotationSupport.getMultipleAnnotations(declaredAnnotations(), annotationClass);
480 }
481
482 /**
483 * {@inheritDoc}
484 */
485 public Annotation[] getDeclaredAnnotations() {
486 return AnnotationParser.toArray(declaredAnnotations());
487 }
488
489 private transient Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
490
491 private synchronized Map<Class<? extends Annotation>, Annotation> declaredAnnotations() {
492 if (declaredAnnotations == null) {
493 declaredAnnotations = AnnotationParser.parseAnnotations(
494 getAnnotationBytes(),
495 sun.misc.SharedSecrets.getJavaLangAccess().
496 getConstantPool(getDeclaringClass()),
497 getDeclaringClass());
498 }
499 return declaredAnnotations;
500 }
501
502 /**
503 * Returns an AnnotatedType object that represents the use of a type to
504 * specify the return type of the method/constructor represented by this
505 * Executable.
506 *
507 * If this Executable represents a constructor, the AnnotatedType object
508 * represents the type of the constructed object.
509 *
510 * If this Executable represents a method, the AnnotatedType object
511 * represents the use of a type to specify the return type of the method.
512 *
513 * @since 1.8
514 */
515 public abstract AnnotatedType getAnnotatedReturnType();
516
517 /* Helper for subclasses of Executable.
518 *
519 * Returns an AnnotatedType object that represents the use of a type to
520 * specify the return type of the method/constructor represented by this
521 * Executable.
522 *
523 * @since 1.8
524 */
525 AnnotatedType getAnnotatedReturnType0(Type returnType) {
526 return TypeAnnotationParser.buildAnnotatedType(getTypeAnnotationBytes(),
527 sun.misc.SharedSecrets.getJavaLangAccess().
528 getConstantPool(getDeclaringClass()),
529 this,
530 getDeclaringClass(),
531 returnType,
532 TypeAnnotation.TypeAnnotationTarget.METHOD_RETURN);
533 }
534
535 /**
536 * Returns an AnnotatedType object that represents the use of a type to
537 * specify the receiver type of the method/constructor represented by this
538 * Executable. The receiver type of a method/constructor is available only
539 * if the method/constructor declares a formal parameter called 'this'.
540 *
541 * Returns null if this Executable represents a constructor or instance
542 * method that either declares no formal parameter called 'this', or
543 * declares a formal parameter called 'this' with no annotations on its
544 * type.
545 *
546 * Returns null if this Executable represents a static method.
547 *
548 * @since 1.8
549 */
550 public AnnotatedType getAnnotatedReceiverType() {
551 return TypeAnnotationParser.buildAnnotatedType(getTypeAnnotationBytes(),
552 sun.misc.SharedSecrets.getJavaLangAccess().
553 getConstantPool(getDeclaringClass()),
554 this,
555 getDeclaringClass(),
556 getDeclaringClass(),
557 TypeAnnotation.TypeAnnotationTarget.METHOD_RECEIVER);
558 }
559
560 /**
561 * Returns an array of AnnotatedType objects that represent the use of
562 * types to specify formal parameter types of the method/constructor
563 * represented by this Executable. The order of the objects in the array
564 * corresponds to the order of the formal parameter types in the
565 * declaration of the method/constructor.
566 *
567 * Returns an array of length 0 if the method/constructor declares no
568 * parameters.
569 *
570 * @since 1.8
571 */
572 public AnnotatedType[] getAnnotatedParameterTypes() {
573 return TypeAnnotationParser.buildAnnotatedTypes(getTypeAnnotationBytes(),
574 sun.misc.SharedSecrets.getJavaLangAccess().
575 getConstantPool(getDeclaringClass()),
576 this,
577 getDeclaringClass(),
578 getParameterTypes(),
579 TypeAnnotation.TypeAnnotationTarget.METHOD_FORMAL_PARAMETER);
580 }
581
582 /**
583 * Returns an array of AnnotatedType objects that represent the use of
584 * types to specify the declared exceptions of the method/constructor
585 * represented by this Executable. The order of the objects in the array
586 * corresponds to the order of the exception types in the declaration of
587 * the method/constructor.
588 *
589 * Returns an array of length 0 if the method/constructor declares no
590 * exceptions.
591 *
592 * @since 1.8
593 */
594 public AnnotatedType[] getAnnotatedExceptionTypes() {
595 return TypeAnnotationParser.buildAnnotatedTypes(getTypeAnnotationBytes(),
596 sun.misc.SharedSecrets.getJavaLangAccess().
597 getConstantPool(getDeclaringClass()),
598 this,
599 getDeclaringClass(),
600 getGenericExceptionTypes(),
601 TypeAnnotation.TypeAnnotationTarget.THROWS);
602 }
603
604 }