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 (including any
241 * synthetic or synthesized parameters) 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 tmp = synthesizeAllParams();
331
332 parameters = tmp;
333 }
334
335 return tmp;
336 }
337
338 private transient volatile Parameter[] parameters;
339
340 private native Parameter[] getParameters0();
341
342 /**
343 * Returns an array of {@code Class} objects that represent the
344 * types of exceptions declared to be thrown by the underlying
345 * executable represented by this object. Returns an array of
346 * length 0 if the executable declares no exceptions in its {@code
347 * throws} clause.
348 *
349 * @return the exception types declared as being thrown by the
350 * executable this object represents
351 */
352 public abstract Class<?>[] getExceptionTypes();
353
354 /**
355 * Returns an array of {@code Type} objects that represent the
356 * exceptions declared to be thrown by this executable object.
357 * Returns an array of length 0 if the underlying executable declares
358 * no exceptions in its {@code throws} clause.
359 *
360 * <p>If an exception type is a type variable or a parameterized
361 * type, it is created. Otherwise, it is resolved.
362 *
363 * @return an array of Types that represent the exception types
364 * thrown by the underlying executable
365 * @throws GenericSignatureFormatError
366 * if the generic method signature does not conform to the format
367 * specified in
368 * <cite>The Java™ Virtual Machine Specification</cite>
369 * @throws TypeNotPresentException if the underlying executable's
370 * {@code throws} clause refers to a non-existent type declaration
371 * @throws MalformedParameterizedTypeException if
372 * the underlying executable's {@code throws} clause refers to a
373 * parameterized type that cannot be instantiated for any reason
374 */
375 public Type[] getGenericExceptionTypes() {
376 Type[] result;
377 if (hasGenericInformation() &&
378 ((result = getGenericInfo().getExceptionTypes()).length > 0))
379 return result;
380 else
381 return getExceptionTypes();
382 }
383
384 /**
385 * Returns a string describing this {@code Executable}, including
386 * any type parameters.
387 */
388 public abstract String toGenericString();
389
390 /**
391 * Returns {@code true} if this executable was declared to take a
392 * variable number of arguments; returns {@code false} otherwise.
393 *
394 * @return {@code true} if an only if this executable was declared
395 * to take a variable number of arguments.
396 */
397 public boolean isVarArgs() {
398 return (getModifiers() & Modifier.VARARGS) != 0;
399 }
400
401 /**
402 * Returns {@code true} if this executable is a synthetic
403 * construct; returns {@code false} otherwise.
404 *
405 * @return true if and only if this executable is a synthetic
406 * construct as defined by
407 * <cite>The Java™ Language Specification</cite>.
408 * @jls 13.1 The Form of a Binary
409 */
410 public boolean isSynthetic() {
411 return Modifier.isSynthetic(getModifiers());
412 }
413
414 /**
415 * Returns an array of arrays that represent the annotations on
416 * the formal parameters, in declaration order, of the executable
417 * represented by this object. (Returns an array of length zero if
418 * the underlying executable is parameterless. If the executable has
419 * one or more parameters, a nested array of length zero is
420 * returned for each parameter with no annotations.) The
421 * annotation objects contained in the returned arrays are
422 * serializable. The caller of this method is free to modify the
423 * returned arrays; it will have no effect on the arrays returned
424 * to other callers.
425 *
426 * @return an array of arrays that represent the annotations on the formal
427 * parameters, in declaration order, of the executable represented by this
428 * object
429 */
430 public abstract Annotation[][] getParameterAnnotations();
431
432 Annotation[][] sharedGetParameterAnnotations(Class<?>[] parameterTypes,
433 byte[] parameterAnnotations) {
434 int numParameters = parameterTypes.length;
435 if (parameterAnnotations == null)
436 return new Annotation[numParameters][0];
437
438 Annotation[][] result = parseParameterAnnotations(parameterAnnotations);
439
440 if (result.length != numParameters)
441 handleParameterNumberMismatch(result.length, numParameters);
442 return result;
443 }
444
445 abstract void handleParameterNumberMismatch(int resultLength, int numParameters);
446
447 /**
448 * {@inheritDoc}
449 * @throws NullPointerException {@inheritDoc}
450 */
451 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
452 Objects.requireNonNull(annotationClass);
453 return annotationClass.cast(declaredAnnotations().get(annotationClass));
454 }
455
456 /**
457 * {@inheritDoc}
458 * @throws NullPointerException {@inheritDoc}
459 * @since 1.8
460 */
461 @Override
462 public <T extends Annotation> T[] getAnnotationsByType(Class<T> annotationClass) {
463 Objects.requireNonNull(annotationClass);
464
465 return AnnotationSupport.getMultipleAnnotations(declaredAnnotations(), annotationClass);
466 }
467
468 /**
469 * {@inheritDoc}
470 */
471 public Annotation[] getDeclaredAnnotations() {
472 return AnnotationParser.toArray(declaredAnnotations());
473 }
474
475 private transient Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
476
477 private synchronized Map<Class<? extends Annotation>, Annotation> declaredAnnotations() {
478 if (declaredAnnotations == null) {
479 declaredAnnotations = AnnotationParser.parseAnnotations(
480 getAnnotationBytes(),
481 sun.misc.SharedSecrets.getJavaLangAccess().
482 getConstantPool(getDeclaringClass()),
483 getDeclaringClass());
484 }
485 return declaredAnnotations;
486 }
487
488 /**
489 * Returns an AnnotatedType object that represents the potentially
490 * annotated return type of the method/constructor represented by this
491 * Executable.
492 *
493 * If this Executable represents a constructor, the AnnotatedType object
494 * represents the type of the constructed object.
495 *
496 * If this Executable represents a method, the AnnotatedType object
497 * represents the use of a type to specify the return type of the method.
498 *
499 * @since 1.8
500 */
501 public abstract AnnotatedType getAnnotatedReturnType();
502
503 /* Helper for subclasses of Executable.
504 *
505 * Returns an AnnotatedType object that represents the use of a type to
506 * specify the return type of the method/constructor represented by this
507 * Executable.
508 *
509 * @since 1.8
510 */
511 AnnotatedType getAnnotatedReturnType0(Type returnType) {
512 return TypeAnnotationParser.buildAnnotatedType(getTypeAnnotationBytes(),
513 sun.misc.SharedSecrets.getJavaLangAccess().
514 getConstantPool(getDeclaringClass()),
515 this,
516 getDeclaringClass(),
517 returnType,
518 TypeAnnotation.TypeAnnotationTarget.METHOD_RETURN_TYPE);
519 }
520
521 /**
522 * Returns an AnnotatedType object that represents the use of a type to
523 * specify the receiver type of the method/constructor represented by this
524 * Executable. The receiver type of a method/constructor is available only
525 * if the method/constructor declares a formal parameter called 'this'.
526 *
527 * Returns null if this Executable represents a constructor or instance
528 * method that either declares no formal parameter called 'this', or
529 * declares a formal parameter called 'this' with no annotations on its
530 * type.
531 *
532 * Returns null if this Executable represents a static method.
533 *
534 * @since 1.8
535 */
536 public AnnotatedType getAnnotatedReceiverType() {
537 return TypeAnnotationParser.buildAnnotatedType(getTypeAnnotationBytes(),
538 sun.misc.SharedSecrets.getJavaLangAccess().
539 getConstantPool(getDeclaringClass()),
540 this,
541 getDeclaringClass(),
542 getDeclaringClass(),
543 TypeAnnotation.TypeAnnotationTarget.METHOD_RECEIVER_TYPE);
544 }
545
546 /**
547 * Returns an array of AnnotatedType objects that represent the use of
548 * types to specify formal parameter types of the method/constructor
549 * represented by this Executable. The order of the objects in the array
550 * corresponds to the order of the formal parameter types in the
551 * declaration of the method/constructor.
552 *
553 * Returns an array of length 0 if the method/constructor declares no
554 * parameters.
555 *
556 * @since 1.8
557 */
558 public AnnotatedType[] getAnnotatedParameterTypes() {
559 throw new UnsupportedOperationException("Not yet");
560 }
561
562 /**
563 * Returns an array of AnnotatedType objects that represent the use of
564 * types to specify the declared exceptions of the method/constructor
565 * represented by this Executable. The order of the objects in the array
566 * corresponds to the order of the exception types in the declaration of
567 * the method/constructor.
568 *
569 * Returns an array of length 0 if the method/constructor declares no
570 * exceptions.
571 *
572 * @since 1.8
573 */
574 public AnnotatedType[] getAnnotatedExceptionTypes() {
575 return TypeAnnotationParser.buildAnnotatedTypes(getTypeAnnotationBytes(),
576 sun.misc.SharedSecrets.getJavaLangAccess().
577 getConstantPool(getDeclaringClass()),
578 this,
579 getDeclaringClass(),
580 getGenericExceptionTypes(),
581 TypeAnnotation.TypeAnnotationTarget.THROWS);
582 }
583
584 }