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
55 /**
56 * Accessor method to allow code sharing
57 */
58 abstract Executable getRoot();
59
60 /**
61 * Does the Executable have generic information.
62 */
63 abstract boolean hasGenericInformation();
64
65 abstract ConstructorRepository getGenericInfo();
66
67 boolean equalParamTypes(Class<?>[] params1, Class<?>[] params2) {
68 /* Avoid unnecessary cloning */
69 if (params1.length == params2.length) {
70 for (int i = 0; i < params1.length; i++) {
71 if (params1[i] != params2[i])
72 return false;
73 }
74 return true;
75 }
76 return false;
77 }
78
79 Annotation[][] parseParameterAnnotations(byte[] parameterAnnotations) {
80 return AnnotationParser.parseParameterAnnotations(
81 parameterAnnotations,
82 sun.misc.SharedSecrets.getJavaLangAccess().
83 getConstantPool(getDeclaringClass()),
84 getDeclaringClass());
85 }
86
87 void separateWithCommas(Class<?>[] types, StringBuilder sb) {
88 for (int j = 0; j < types.length; j++) {
89 sb.append(types[j].getTypeName());
90 if (j < (types.length - 1))
91 sb.append(",");
92 }
93
94 }
95
96 void printModifiersIfNonzero(StringBuilder sb, int mask, boolean isDefault) {
97 int mod = getModifiers() & mask;
98
99 if (mod != 0 && !isDefault) {
100 sb.append(Modifier.toString(mod)).append(' ');
101 } else {
102 int access_mod = mod & Modifier.ACCESS_MODIFIERS;
103 if (access_mod != 0)
104 sb.append(Modifier.toString(access_mod)).append(' ');
105 if (isDefault)
106 sb.append("default ");
107 mod = (mod & ~Modifier.ACCESS_MODIFIERS);
108 if (mod != 0)
109 sb.append(Modifier.toString(mod)).append(' ');
110 }
111 }
112
113 String sharedToString(int modifierMask,
114 boolean isDefault,
115 Class<?>[] parameterTypes,
116 Class<?>[] exceptionTypes) {
117 try {
118 StringBuilder sb = new StringBuilder();
119
120 printModifiersIfNonzero(sb, modifierMask, isDefault);
121 specificToStringHeader(sb);
122
123 sb.append('(');
124 separateWithCommas(parameterTypes, sb);
125 sb.append(')');
126 if (exceptionTypes.length > 0) {
127 sb.append(" throws ");
128 separateWithCommas(exceptionTypes, sb);
129 }
130 return sb.toString();
131 } catch (Exception e) {
132 return "<" + e + ">";
133 }
134 }
135
136 /**
137 * Generate toString header information specific to a method or
138 * constructor.
139 */
140 abstract void specificToStringHeader(StringBuilder sb);
141
142 String sharedToGenericString(int modifierMask, boolean isDefault) {
143 try {
144 StringBuilder sb = new StringBuilder();
145
146 printModifiersIfNonzero(sb, modifierMask, isDefault);
147
148 TypeVariable<?>[] typeparms = getTypeParameters();
149 if (typeparms.length > 0) {
150 boolean first = true;
151 sb.append('<');
152 for(TypeVariable<?> typeparm: typeparms) {
153 if (!first)
154 sb.append(',');
155 // Class objects can't occur here; no need to test
156 // and call Class.getName().
157 sb.append(typeparm.toString());
158 first = false;
159 }
160 sb.append("> ");
161 }
162
163 specificToGenericStringHeader(sb);
164
165 sb.append('(');
166 Type[] params = getGenericParameterTypes();
167 for (int j = 0; j < params.length; j++) {
168 String param = params[j].getTypeName();
169 if (isVarArgs() && (j == params.length - 1)) // replace T[] with T...
170 param = param.replaceFirst("\\[\\]$", "...");
171 sb.append(param);
172 if (j < (params.length - 1))
173 sb.append(',');
174 }
175 sb.append(')');
176 Type[] exceptions = getGenericExceptionTypes();
177 if (exceptions.length > 0) {
178 sb.append(" throws ");
179 for (int k = 0; k < exceptions.length; k++) {
180 sb.append((exceptions[k] instanceof Class)?
181 ((Class)exceptions[k]).getName():
182 exceptions[k].toString());
183 if (k < (exceptions.length - 1))
184 sb.append(',');
185 }
186 }
187 return sb.toString();
188 } catch (Exception e) {
189 return "<" + e + ">";
190 }
191 }
192
193 /**
194 * Generate toGenericString header information specific to a
195 * method or constructor.
196 */
197 abstract void specificToGenericStringHeader(StringBuilder sb);
198
199 /**
200 * Returns the {@code Class} object representing the class or interface
201 * that declares the executable represented by this object.
202 */
203 public abstract Class<?> getDeclaringClass();
204
205 /**
206 * Returns the name of the executable represented by this object.
207 */
208 public abstract String getName();
209
210 /**
211 * Returns the Java language {@linkplain Modifier modifiers} for
212 * the executable represented by this object.
213 */
214 public abstract int getModifiers();
215
216 /**
217 * Returns an array of {@code TypeVariable} objects that represent the
218 * type variables declared by the generic declaration represented by this
219 * {@code GenericDeclaration} object, in declaration order. Returns an
220 * array of length 0 if the underlying generic declaration declares no type
221 * variables.
222 *
223 * @return an array of {@code TypeVariable} objects that represent
224 * the type variables declared by this generic declaration
225 * @throws GenericSignatureFormatError if the generic
226 * signature of this generic declaration does not conform to
227 * the format specified in
228 * <cite>The Java™ Virtual Machine Specification</cite>
229 */
230 public abstract TypeVariable<?>[] getTypeParameters();
231
232 /**
233 * Returns an array of {@code Class} objects that represent the formal
234 * parameter types, in declaration order, of the executable
235 * represented by this object. Returns an array of length
236 * 0 if the underlying executable takes no parameters.
237 *
238 * @return the parameter types for the executable this object
239 * represents
240 */
241 public abstract Class<?>[] getParameterTypes();
242
243 /**
244 * Returns the number of formal parameters (whether explicitly
245 * declared or implicitly declared or neither) for the executable
246 * represented by this object.
247 *
248 * @return The number of formal parameters for the executable this
249 * object represents
250 */
251 public int getParameterCount() {
252 throw new AbstractMethodError();
253 }
254
255 /**
256 * Returns an array of {@code Type} objects that represent the formal
257 * parameter types, in declaration order, of the executable represented by
258 * this object. Returns an array of length 0 if the
259 * underlying executable takes no parameters.
260 *
261 * <p>If a formal parameter type is a parameterized type,
262 * the {@code Type} object returned for it must accurately reflect
263 * the actual type parameters used in the source code.
264 *
265 * <p>If a formal parameter type is a type variable or a parameterized
266 * type, it is created. Otherwise, it is resolved.
267 *
268 * @return an array of {@code Type}s that represent the formal
269 * parameter types of the underlying executable, in declaration order
270 * @throws GenericSignatureFormatError
271 * if the generic method signature does not conform to the format
272 * specified in
273 * <cite>The Java™ Virtual Machine Specification</cite>
274 * @throws TypeNotPresentException if any of the parameter
275 * types of the underlying executable refers to a non-existent type
276 * declaration
277 * @throws MalformedParameterizedTypeException if any of
278 * the underlying executable's parameter types refer to a parameterized
279 * type that cannot be instantiated for any reason
280 */
281 public Type[] getGenericParameterTypes() {
282 if (hasGenericInformation())
283 return getGenericInfo().getParameterTypes();
284 else
285 return getParameterTypes();
286 }
287
288 /**
289 * Returns an array of {@code Parameter} objects that represent
290 * all the parameters to the underlying executable represented by
291 * this object. Returns an array of length 0 if the executable
292 * has no parameters.
293 *
294 * <p>The parameters of the underlying executable do not necessarily
295 * have unique names, or names that are legal identifiers in the
296 * Java programming language (JLS 3.8).
297 *
298 * @throws MalformedParametersException if the class file contains
299 * a MethodParameters attribute that is improperly formatted.
300 * @return an array of {@code Parameter} objects representing all
301 * the parameters to the executable this object represents.
302 */
303 public Parameter[] getParameters() {
304 // TODO: This may eventually need to be guarded by security
305 // mechanisms similar to those in Field, Method, etc.
306 //
307 // Need to copy the cached array to prevent users from messing
308 // with it. Since parameters are immutable, we can
309 // shallow-copy.
310 return privateGetParameters().clone();
311 }
312
313 private Parameter[] synthesizeAllParams() {
314 final int realparams = getParameterCount();
315 final Parameter[] out = new Parameter[realparams];
316 for (int i = 0; i < realparams; i++)
317 // TODO: is there a way to synthetically derive the
318 // modifiers? Probably not in the general case, since
319 // we'd have no way of knowing about them, but there
320 // may be specific cases.
321 out[i] = new Parameter("arg" + i, 0, this, i);
322 return out;
323 }
324
325 private void verifyParameters(final Parameter[] parameters) {
326 final int mask = Modifier.FINAL | Modifier.SYNTHETIC | Modifier.MANDATED;
327
328 if (getParameterTypes().length != parameters.length)
329 throw new MalformedParametersException("Wrong number of parameters in MethodParameters attribute");
330
331 for (Parameter parameter : parameters) {
332 final String name = parameter.getRealName();
333 final int mods = parameter.getModifiers();
334
335 if (name != null) {
336 if (name.isEmpty() || name.indexOf('.') != -1 ||
337 name.indexOf(';') != -1 || name.indexOf('[') != -1 ||
338 name.indexOf('/') != -1) {
339 throw new MalformedParametersException("Invalid parameter name \"" + name + "\"");
340 }
341 }
342
343 if (mods != (mods & mask)) {
344 throw new MalformedParametersException("Invalid parameter modifiers");
345 }
346 }
347 }
348
349 private Parameter[] privateGetParameters() {
350 // Use tmp to avoid multiple writes to a volatile.
351 Parameter[] tmp = parameters;
352
353 if (tmp == null) {
354
355 // Otherwise, go to the JVM to get them
356 try {
357 tmp = getParameters0();
358 } catch(IllegalArgumentException e) {
359 // Rethrow ClassFormatErrors
360 throw new MalformedParametersException("Invalid constant pool index");
361 }
362
363 // If we get back nothing, then synthesize parameters
364 if (tmp == null) {
365 hasRealParameterData = false;
366 tmp = synthesizeAllParams();
367 } else {
368 hasRealParameterData = true;
369 verifyParameters(tmp);
370 }
371
372 parameters = tmp;
373 }
374
375 return tmp;
376 }
377
378 boolean hasRealParameterData() {
379 // If this somehow gets called before parameters gets
380 // initialized, force it into existence.
381 if (parameters == null) {
382 privateGetParameters();
383 }
384 return hasRealParameterData;
385 }
386
387 private transient volatile boolean hasRealParameterData;
388 private transient volatile Parameter[] parameters;
389
390 private native Parameter[] getParameters0();
391 native byte[] getTypeAnnotationBytes0();
392
393 // Needed by reflectaccess
394 byte[] getTypeAnnotationBytes() {
395 return getTypeAnnotationBytes0();
396 }
397
398 /**
399 * Returns an array of {@code Class} objects that represent the
400 * types of exceptions declared to be thrown by the underlying
401 * executable represented by this object. Returns an array of
402 * length 0 if the executable declares no exceptions in its {@code
403 * throws} clause.
404 *
405 * @return the exception types declared as being thrown by the
406 * executable this object represents
407 */
408 public abstract Class<?>[] getExceptionTypes();
409
410 /**
411 * Returns an array of {@code Type} objects that represent the
412 * exceptions declared to be thrown by this executable object.
413 * Returns an array of length 0 if the underlying executable declares
414 * no exceptions in its {@code throws} clause.
415 *
416 * <p>If an exception type is a type variable or a parameterized
417 * type, it is created. Otherwise, it is resolved.
418 *
419 * @return an array of Types that represent the exception types
420 * thrown by the underlying executable
421 * @throws GenericSignatureFormatError
422 * if the generic method signature does not conform to the format
423 * specified in
424 * <cite>The Java™ Virtual Machine Specification</cite>
425 * @throws TypeNotPresentException if the underlying executable's
426 * {@code throws} clause refers to a non-existent type declaration
427 * @throws MalformedParameterizedTypeException if
428 * the underlying executable's {@code throws} clause refers to a
429 * parameterized type that cannot be instantiated for any reason
430 */
431 public Type[] getGenericExceptionTypes() {
432 Type[] result;
433 if (hasGenericInformation() &&
434 ((result = getGenericInfo().getExceptionTypes()).length > 0))
435 return result;
436 else
437 return getExceptionTypes();
438 }
439
440 /**
441 * Returns a string describing this {@code Executable}, including
442 * any type parameters.
443 * @return a string describing this {@code Executable}, including
444 * any type parameters
445 */
446 public abstract String toGenericString();
447
448 /**
449 * Returns {@code true} if this executable was declared to take a
450 * variable number of arguments; returns {@code false} otherwise.
451 *
452 * @return {@code true} if an only if this executable was declared
453 * to take a variable number of arguments.
454 */
455 public boolean isVarArgs() {
456 return (getModifiers() & Modifier.VARARGS) != 0;
457 }
458
459 /**
460 * Returns {@code true} if this executable is a synthetic
461 * construct; returns {@code false} otherwise.
462 *
463 * @return true if and only if this executable is a synthetic
464 * construct as defined by
465 * <cite>The Java™ Language Specification</cite>.
466 * @jls 13.1 The Form of a Binary
467 */
468 public boolean isSynthetic() {
469 return Modifier.isSynthetic(getModifiers());
470 }
471
472 /**
473 * Returns an array of arrays of {@code Annotation}s that
474 * represent the annotations on the formal parameters, in
475 * declaration order, of the {@code Executable} represented by
476 * this object. Synthetic and mandated parameters (see
477 * explanation below), such as the outer "this" parameter to an
478 * inner class constructor will be represented in the returned
479 * array. If the executable has no parameters (meaning no formal,
480 * no synthetic, and no mandated parameters), a zero-length array
481 * will be returned. If the {@code Executable} has one or more
482 * parameters, a nested array of length zero is returned for each
483 * parameter with no annotations. The annotation objects contained
484 * in the returned arrays are serializable. The caller of this
485 * method is free to modify the returned arrays; it will have no
486 * effect on the arrays returned to other callers.
487 *
488 * A compiler may add extra parameters that are implicitly
489 * declared in source ("mandated"), as well as parameters that
490 * are neither implicitly nor explicitly declared in source
491 * ("synthetic") to the parameter list for a method. See {@link
492 * java.lang.reflect.Parameter} for more information.
493 *
494 * @see java.lang.reflect.Parameter
495 * @see java.lang.reflect.Parameter#getAnnotations
496 * @return an array of arrays that represent the annotations on
497 * the formal and implicit parameters, in declaration order, of
498 * the executable represented by this object
499 */
500 public abstract Annotation[][] getParameterAnnotations();
501
502 Annotation[][] sharedGetParameterAnnotations(Class<?>[] parameterTypes,
503 byte[] parameterAnnotations) {
504 int numParameters = parameterTypes.length;
505 if (parameterAnnotations == null)
506 return new Annotation[numParameters][0];
507
508 Annotation[][] result = parseParameterAnnotations(parameterAnnotations);
509
510 if (result.length != numParameters)
511 handleParameterNumberMismatch(result.length, numParameters);
512 return result;
513 }
514
515 abstract void handleParameterNumberMismatch(int resultLength, int numParameters);
516
517 /**
518 * {@inheritDoc}
519 * @throws NullPointerException {@inheritDoc}
520 */
521 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
522 Objects.requireNonNull(annotationClass);
523 return annotationClass.cast(declaredAnnotations().get(annotationClass));
524 }
525
526 /**
527 * {@inheritDoc}
528 * @throws NullPointerException {@inheritDoc}
529 */
530 @Override
531 public <T extends Annotation> T[] getAnnotationsByType(Class<T> annotationClass) {
532 Objects.requireNonNull(annotationClass);
533
534 return AnnotationSupport.getDirectlyAndIndirectlyPresent(declaredAnnotations(), annotationClass);
535 }
536
537 /**
538 * {@inheritDoc}
539 */
540 public Annotation[] getDeclaredAnnotations() {
541 return AnnotationParser.toArray(declaredAnnotations());
542 }
543
544 private transient Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
545
546 private synchronized Map<Class<? extends Annotation>, Annotation> declaredAnnotations() {
547 if (declaredAnnotations == null) {
548 Executable root = getRoot();
549 if (root != null) {
550 declaredAnnotations = root.declaredAnnotations();
551 } else {
552 declaredAnnotations = AnnotationParser.parseAnnotations(
553 getAnnotationBytes(),
554 sun.misc.SharedSecrets.getJavaLangAccess().
555 getConstantPool(getDeclaringClass()),
556 getDeclaringClass());
557 }
558 }
559 return declaredAnnotations;
560 }
561
562 /**
563 * Returns an {@code AnnotatedType} object that represents the use of a type to
564 * specify the return type of the method/constructor represented by this
565 * Executable.
566 *
567 * If this {@code Executable} object represents a constructor, the {@code
568 * AnnotatedType} object represents the type of the constructed object.
569 *
570 * If this {@code Executable} object represents a method, the {@code
571 * AnnotatedType} object represents the use of a type to specify the return
572 * type of the method.
573 *
574 * @return an object representing the return type of the method
575 * or constructor represented by this {@code Executable}
576 */
577 public abstract AnnotatedType getAnnotatedReturnType();
578
579 /* Helper for subclasses of Executable.
580 *
581 * Returns an AnnotatedType object that represents the use of a type to
582 * specify the return type of the method/constructor represented by this
583 * Executable.
584 */
585 AnnotatedType getAnnotatedReturnType0(Type returnType) {
586 return TypeAnnotationParser.buildAnnotatedType(getTypeAnnotationBytes0(),
587 sun.misc.SharedSecrets.getJavaLangAccess().
588 getConstantPool(getDeclaringClass()),
589 this,
590 getDeclaringClass(),
591 returnType,
592 TypeAnnotation.TypeAnnotationTarget.METHOD_RETURN);
593 }
594
595 /**
596 * Returns an {@code AnnotatedType} object that represents the use of a
597 * type to specify the receiver type of the method/constructor represented
598 * by this {@code Executable} object.
599 *
600 * The receiver type of a method/constructor is available only if the
601 * method/constructor has a receiver parameter (JLS 8.4.1). If this {@code
602 * Executable} object <em>represents an instance method or represents a
603 * constructor of an inner member class</em>, and the
604 * method/constructor <em>either</em> has no receiver parameter or has a
605 * receiver parameter with no annotations on its type, then the return
606 * value is an {@code AnnotatedType} object representing an element with no
607 * annotations.
608 *
609 * If this {@code Executable} object represents a static method or
610 * represents a constructor of a top level, static member, local, or
611 * anoymous class, then the return value is null.
612 *
613 * @return an object representing the receiver type of the method or
614 * constructor represented by this {@code Executable} or {@code null} if
615 * this {@code Executable} can not have a receiver parameter
616 */
617 public AnnotatedType getAnnotatedReceiverType() {
618 if (Modifier.isStatic(this.getModifiers()))
619 return null;
620 return TypeAnnotationParser.buildAnnotatedType(getTypeAnnotationBytes0(),
621 sun.misc.SharedSecrets.getJavaLangAccess().
622 getConstantPool(getDeclaringClass()),
623 this,
624 getDeclaringClass(),
625 getDeclaringClass(),
626 TypeAnnotation.TypeAnnotationTarget.METHOD_RECEIVER);
627 }
628
629 /**
630 * Returns an array of {@code AnnotatedType} objects that represent the use
631 * of types to specify formal parameter types of the method/constructor
632 * represented by this Executable. The order of the objects in the array
633 * corresponds to the order of the formal parameter types in the
634 * declaration of the method/constructor.
635 *
636 * Returns an array of length 0 if the method/constructor declares no
637 * parameters.
638 *
639 * @return an array of objects representing the types of the
640 * formal parameters of the method or constructor represented by this
641 * {@code Executable}
642 */
643 public AnnotatedType[] getAnnotatedParameterTypes() {
644 return TypeAnnotationParser.buildAnnotatedTypes(getTypeAnnotationBytes0(),
645 sun.misc.SharedSecrets.getJavaLangAccess().
646 getConstantPool(getDeclaringClass()),
647 this,
648 getDeclaringClass(),
649 getGenericParameterTypes(),
650 TypeAnnotation.TypeAnnotationTarget.METHOD_FORMAL_PARAMETER);
651 }
652
653 /**
654 * Returns an array of {@code AnnotatedType} objects that represent the use
655 * of types to specify the declared exceptions of the method/constructor
656 * represented by this Executable. The order of the objects in the array
657 * corresponds to the order of the exception types in the declaration of
658 * the method/constructor.
659 *
660 * Returns an array of length 0 if the method/constructor declares no
661 * exceptions.
662 *
663 * @return an array of objects representing the declared
664 * exceptions of the method or constructor represented by this {@code
665 * Executable}
666 */
667 public AnnotatedType[] getAnnotatedExceptionTypes() {
668 return TypeAnnotationParser.buildAnnotatedTypes(getTypeAnnotationBytes0(),
669 sun.misc.SharedSecrets.getJavaLangAccess().
670 getConstantPool(getDeclaringClass()),
671 this,
672 getDeclaringClass(),
673 getGenericExceptionTypes(),
674 TypeAnnotation.TypeAnnotationTarget.THROWS);
675 }
676
677 }