1 /*
2 * Copyright (c) 2008, 2015, 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.invoke;
27
28 import sun.invoke.util.BytecodeDescriptor;
29 import sun.invoke.util.VerifyAccess;
30
31 import java.lang.reflect.Constructor;
32 import java.lang.reflect.Field;
33 import java.lang.reflect.Method;
34 import java.lang.reflect.Member;
35 import java.lang.reflect.Modifier;
36 import java.lang.reflect.Module;
37 import java.util.ArrayList;
38 import java.util.Arrays;
39 import java.util.Collections;
40 import java.util.Iterator;
41 import java.util.List;
42 import static java.lang.invoke.MethodHandleNatives.Constants.*;
43 import static java.lang.invoke.MethodHandleStatics.*;
44 import java.util.Objects;
45
46 /**
47 * A {@code MemberName} is a compact symbolic datum which fully characterizes
48 * a method or field reference.
49 * A member name refers to a field, method, constructor, or member type.
50 * Every member name has a simple name (a string) and a type (either a Class or MethodType).
51 * A member name may also have a non-null declaring class, or it may be simply
52 * a naked name/type pair.
53 * A member name may also have non-zero modifier flags.
54 * Finally, a member name may be either resolved or unresolved.
55 * If it is resolved, the existence of the named
56 * <p>
57 * Whether resolved or not, a member name provides no access rights or
58 * invocation capability to its possessor. It is merely a compact
59 * representation of all symbolic information necessary to link to
60 * and properly use the named member.
61 * <p>
62 * When resolved, a member name's internal implementation may include references to JVM metadata.
63 * This representation is stateless and only descriptive.
64 * It provides no private information and no capability to use the member.
65 * <p>
66 * By contrast, a {@linkplain java.lang.reflect.Method} contains fuller information
67 * about the internals of a method (except its bytecodes) and also
68 * allows invocation. A MemberName is much lighter than a Method,
69 * since it contains about 7 fields to the 16 of Method (plus its sub-arrays),
70 * and those seven fields omit much of the information in Method.
71 * @author jrose
72 */
73 /*non-public*/ final class MemberName implements Member, Cloneable {
74 private Class<?> clazz; // class in which the method is defined
75 private String name; // may be null if not yet materialized
76 private Object type; // may be null if not yet materialized
77 private int flags; // modifier bits; see reflect.Modifier
78 //@Injected JVM_Method* vmtarget;
79 //@Injected int vmindex;
80 private Object resolution; // if null, this guy is resolved
81
82 /** Return the declaring class of this member.
83 * In the case of a bare name and type, the declaring class will be null.
84 */
85 public Class<?> getDeclaringClass() {
86 return clazz;
87 }
88
89 /** Utility method producing the class loader of the declaring class. */
90 public ClassLoader getClassLoader() {
91 return clazz.getClassLoader();
92 }
93
94 /** Return the simple name of this member.
95 * For a type, it is the same as {@link Class#getSimpleName}.
96 * For a method or field, it is the simple name of the member.
97 * For a constructor, it is always {@code "<init>"}.
98 */
99 public String getName() {
100 if (name == null) {
101 expandFromVM();
102 if (name == null) {
103 return null;
104 }
105 }
106 return name;
107 }
108
109 public MethodType getMethodOrFieldType() {
110 if (isInvocable())
111 return getMethodType();
112 if (isGetter())
113 return MethodType.methodType(getFieldType());
114 if (isSetter())
115 return MethodType.methodType(void.class, getFieldType());
116 throw new InternalError("not a method or field: "+this);
117 }
118
119 /** Return the declared type of this member, which
120 * must be a method or constructor.
121 */
122 public MethodType getMethodType() {
123 if (type == null) {
124 expandFromVM();
125 if (type == null) {
126 return null;
127 }
128 }
129 if (!isInvocable()) {
130 throw newIllegalArgumentException("not invocable, no method type");
131 }
132
133 {
134 // Get a snapshot of type which doesn't get changed by racing threads.
135 final Object type = this.type;
136 if (type instanceof MethodType) {
137 return (MethodType) type;
138 }
139 }
140
141 // type is not a MethodType yet. Convert it thread-safely.
142 synchronized (this) {
143 if (type instanceof String) {
144 String sig = (String) type;
145 MethodType res = MethodType.fromDescriptor(sig, getClassLoader());
146 type = res;
147 } else if (type instanceof Object[]) {
148 Object[] typeInfo = (Object[]) type;
149 Class<?>[] ptypes = (Class<?>[]) typeInfo[1];
150 Class<?> rtype = (Class<?>) typeInfo[0];
151 MethodType res = MethodType.methodType(rtype, ptypes);
152 type = res;
153 }
154 // Make sure type is a MethodType for racing threads.
155 assert type instanceof MethodType : "bad method type " + type;
156 }
157 return (MethodType) type;
158 }
159
160 /** Return the actual type under which this method or constructor must be invoked.
161 * For non-static methods or constructors, this is the type with a leading parameter,
162 * a reference to declaring class. For static methods, it is the same as the declared type.
163 */
164 public MethodType getInvocationType() {
165 MethodType itype = getMethodOrFieldType();
166 if (isConstructor() && getReferenceKind() == REF_newInvokeSpecial)
167 return itype.changeReturnType(clazz);
168 if (!isStatic())
169 return itype.insertParameterTypes(0, clazz);
170 return itype;
171 }
172
173 /** Utility method producing the parameter types of the method type. */
174 public Class<?>[] getParameterTypes() {
175 return getMethodType().parameterArray();
176 }
177
178 /** Utility method producing the return type of the method type. */
179 public Class<?> getReturnType() {
180 return getMethodType().returnType();
181 }
182
183 /** Return the declared type of this member, which
184 * must be a field or type.
185 * If it is a type member, that type itself is returned.
186 */
187 public Class<?> getFieldType() {
188 if (type == null) {
189 expandFromVM();
190 if (type == null) {
191 return null;
192 }
193 }
194 if (isInvocable()) {
195 throw newIllegalArgumentException("not a field or nested class, no simple type");
196 }
197
198 {
199 // Get a snapshot of type which doesn't get changed by racing threads.
200 final Object type = this.type;
201 if (type instanceof Class<?>) {
202 return (Class<?>) type;
203 }
204 }
205
206 // type is not a Class yet. Convert it thread-safely.
207 synchronized (this) {
208 if (type instanceof String) {
209 String sig = (String) type;
210 MethodType mtype = MethodType.fromDescriptor("()"+sig, getClassLoader());
211 Class<?> res = mtype.returnType();
212 type = res;
213 }
214 // Make sure type is a Class for racing threads.
215 assert type instanceof Class<?> : "bad field type " + type;
216 }
217 return (Class<?>) type;
218 }
219
220 /** Utility method to produce either the method type or field type of this member. */
221 public Object getType() {
222 return (isInvocable() ? getMethodType() : getFieldType());
223 }
224
225 /** Utility method to produce the signature of this member,
226 * used within the class file format to describe its type.
227 */
228 public String getSignature() {
229 if (type == null) {
230 expandFromVM();
231 if (type == null) {
232 return null;
233 }
234 }
235 if (isInvocable())
236 return BytecodeDescriptor.unparse(getMethodType());
237 else
238 return BytecodeDescriptor.unparse(getFieldType());
239 }
240
241 /** Return the modifier flags of this member.
242 * @see java.lang.reflect.Modifier
243 */
244 public int getModifiers() {
245 return (flags & RECOGNIZED_MODIFIERS);
246 }
247
248 /** Return the reference kind of this member, or zero if none.
249 */
250 public byte getReferenceKind() {
251 return (byte) ((flags >>> MN_REFERENCE_KIND_SHIFT) & MN_REFERENCE_KIND_MASK);
252 }
253 private boolean referenceKindIsConsistent() {
254 byte refKind = getReferenceKind();
255 if (refKind == REF_NONE) return isType();
256 if (isField()) {
257 assert(staticIsConsistent());
258 assert(MethodHandleNatives.refKindIsField(refKind));
259 } else if (isConstructor()) {
260 assert(refKind == REF_newInvokeSpecial || refKind == REF_invokeSpecial);
261 } else if (isMethod()) {
262 assert(staticIsConsistent());
263 assert(MethodHandleNatives.refKindIsMethod(refKind));
264 if (clazz.isInterface())
265 assert(refKind == REF_invokeInterface ||
266 refKind == REF_invokeStatic ||
267 refKind == REF_invokeSpecial ||
268 refKind == REF_invokeVirtual && isObjectPublicMethod());
269 } else {
270 assert(false);
271 }
272 return true;
273 }
274 private boolean isObjectPublicMethod() {
275 if (clazz == Object.class) return true;
276 MethodType mtype = getMethodType();
277 if (name.equals("toString") && mtype.returnType() == String.class && mtype.parameterCount() == 0)
278 return true;
279 if (name.equals("hashCode") && mtype.returnType() == int.class && mtype.parameterCount() == 0)
280 return true;
281 if (name.equals("equals") && mtype.returnType() == boolean.class && mtype.parameterCount() == 1 && mtype.parameterType(0) == Object.class)
282 return true;
283 return false;
284 }
285 /*non-public*/ boolean referenceKindIsConsistentWith(int originalRefKind) {
286 int refKind = getReferenceKind();
287 if (refKind == originalRefKind) return true;
288 switch (originalRefKind) {
289 case REF_invokeInterface:
290 // Looking up an interface method, can get (e.g.) Object.hashCode
291 assert(refKind == REF_invokeVirtual ||
292 refKind == REF_invokeSpecial) : this;
293 return true;
294 case REF_invokeVirtual:
295 case REF_newInvokeSpecial:
296 // Looked up a virtual, can get (e.g.) final String.hashCode.
297 assert(refKind == REF_invokeSpecial) : this;
298 return true;
299 }
300 assert(false) : this+" != "+MethodHandleNatives.refKindName((byte)originalRefKind);
301 return true;
302 }
303 private boolean staticIsConsistent() {
304 byte refKind = getReferenceKind();
305 return MethodHandleNatives.refKindIsStatic(refKind) == isStatic() || getModifiers() == 0;
306 }
307 private boolean vminfoIsConsistent() {
308 byte refKind = getReferenceKind();
309 assert(isResolved()); // else don't call
310 Object vminfo = MethodHandleNatives.getMemberVMInfo(this);
311 assert(vminfo instanceof Object[]);
312 long vmindex = (Long) ((Object[])vminfo)[0];
313 Object vmtarget = ((Object[])vminfo)[1];
314 if (MethodHandleNatives.refKindIsField(refKind)) {
315 assert(vmindex >= 0) : vmindex + ":" + this;
316 assert(vmtarget instanceof Class);
317 } else {
318 if (MethodHandleNatives.refKindDoesDispatch(refKind))
319 assert(vmindex >= 0) : vmindex + ":" + this;
320 else
321 assert(vmindex < 0) : vmindex;
322 assert(vmtarget instanceof MemberName) : vmtarget + " in " + this;
323 }
324 return true;
325 }
326
327 private MemberName changeReferenceKind(byte refKind, byte oldKind) {
328 assert(getReferenceKind() == oldKind);
329 assert(MethodHandleNatives.refKindIsValid(refKind));
330 flags += (((int)refKind - oldKind) << MN_REFERENCE_KIND_SHIFT);
331 return this;
332 }
333
334 private boolean testFlags(int mask, int value) {
335 return (flags & mask) == value;
336 }
337 private boolean testAllFlags(int mask) {
338 return testFlags(mask, mask);
339 }
340 private boolean testAnyFlags(int mask) {
341 return !testFlags(mask, 0);
342 }
343
344 /** Utility method to query if this member is a method handle invocation (invoke or invokeExact).
345 * Also returns true for the non-public MH.invokeBasic.
346 */
347 public boolean isMethodHandleInvoke() {
348 final int bits = MH_INVOKE_MODS &~ Modifier.PUBLIC;
349 final int negs = Modifier.STATIC;
350 if (testFlags(bits | negs, bits) &&
351 clazz == MethodHandle.class) {
352 return isMethodHandleInvokeName(name);
353 }
354 return false;
355 }
356 public static boolean isMethodHandleInvokeName(String name) {
357 switch (name) {
358 case "invoke":
359 case "invokeExact":
360 case "invokeBasic": // internal sig-poly method
361 return true;
362 default:
363 return false;
364 }
365 }
366 public boolean isVarHandleMethodInvoke() {
367 final int bits = MH_INVOKE_MODS &~ Modifier.PUBLIC;
368 final int negs = Modifier.STATIC;
369 if (testFlags(bits | negs, bits) &&
370 clazz == VarHandle.class) {
371 return isVarHandleMethodInvokeName(name);
372 }
373 return false;
374 }
375 public static boolean isVarHandleMethodInvokeName(String name) {
376 try {
377 VarHandle.AccessMode.valueOf(name);
378 return true;
379 } catch (IllegalArgumentException e) {
380 return false;
381 }
382 }
383 private static final int MH_INVOKE_MODS = Modifier.NATIVE | Modifier.FINAL | Modifier.PUBLIC;
384
385 /** Utility method to query the modifier flags of this member. */
386 public boolean isStatic() {
387 return Modifier.isStatic(flags);
388 }
389 /** Utility method to query the modifier flags of this member. */
390 public boolean isPublic() {
391 return Modifier.isPublic(flags);
392 }
393 /** Utility method to query the modifier flags of this member. */
394 public boolean isPrivate() {
395 return Modifier.isPrivate(flags);
396 }
397 /** Utility method to query the modifier flags of this member. */
398 public boolean isProtected() {
399 return Modifier.isProtected(flags);
400 }
401 /** Utility method to query the modifier flags of this member. */
402 public boolean isFinal() {
403 return Modifier.isFinal(flags);
404 }
405 /** Utility method to query whether this member or its defining class is final. */
406 public boolean canBeStaticallyBound() {
407 return Modifier.isFinal(flags | clazz.getModifiers());
408 }
409 /** Utility method to query the modifier flags of this member. */
410 public boolean isVolatile() {
411 return Modifier.isVolatile(flags);
412 }
413 /** Utility method to query the modifier flags of this member. */
414 public boolean isAbstract() {
415 return Modifier.isAbstract(flags);
416 }
417 /** Utility method to query the modifier flags of this member. */
418 public boolean isNative() {
419 return Modifier.isNative(flags);
420 }
421 // let the rest (native, volatile, transient, etc.) be tested via Modifier.isFoo
422
423 // unofficial modifier flags, used by HotSpot:
424 static final int BRIDGE = 0x00000040;
425 static final int VARARGS = 0x00000080;
426 static final int SYNTHETIC = 0x00001000;
427 static final int ANNOTATION= 0x00002000;
428 static final int ENUM = 0x00004000;
429 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */
430 public boolean isBridge() {
431 return testAllFlags(IS_METHOD | BRIDGE);
432 }
433 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */
434 public boolean isVarargs() {
435 return testAllFlags(VARARGS) && isInvocable();
436 }
437 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */
438 public boolean isSynthetic() {
439 return testAllFlags(SYNTHETIC);
440 }
441
442 static final String CONSTRUCTOR_NAME = "<init>"; // the ever-popular
443
444 // modifiers exported by the JVM:
445 static final int RECOGNIZED_MODIFIERS = 0xFFFF;
446
447 // private flags, not part of RECOGNIZED_MODIFIERS:
448 static final int
449 IS_METHOD = MN_IS_METHOD, // method (not constructor)
450 IS_CONSTRUCTOR = MN_IS_CONSTRUCTOR, // constructor
451 IS_FIELD = MN_IS_FIELD, // field
452 IS_TYPE = MN_IS_TYPE, // nested type
453 CALLER_SENSITIVE = MN_CALLER_SENSITIVE; // @CallerSensitive annotation detected
454
455 static final int ALL_ACCESS = Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED;
456 static final int ALL_KINDS = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE;
457 static final int IS_INVOCABLE = IS_METHOD | IS_CONSTRUCTOR;
458 static final int IS_FIELD_OR_METHOD = IS_METHOD | IS_FIELD;
459 static final int SEARCH_ALL_SUPERS = MN_SEARCH_SUPERCLASSES | MN_SEARCH_INTERFACES;
460
461 /** Utility method to query whether this member is a method or constructor. */
462 public boolean isInvocable() {
463 return testAnyFlags(IS_INVOCABLE);
464 }
465 /** Utility method to query whether this member is a method, constructor, or field. */
466 public boolean isFieldOrMethod() {
467 return testAnyFlags(IS_FIELD_OR_METHOD);
468 }
469 /** Query whether this member is a method. */
470 public boolean isMethod() {
471 return testAllFlags(IS_METHOD);
472 }
473 /** Query whether this member is a constructor. */
474 public boolean isConstructor() {
475 return testAllFlags(IS_CONSTRUCTOR);
476 }
477 /** Query whether this member is a field. */
478 public boolean isField() {
479 return testAllFlags(IS_FIELD);
480 }
481 /** Query whether this member is a type. */
482 public boolean isType() {
483 return testAllFlags(IS_TYPE);
484 }
485 /** Utility method to query whether this member is neither public, private, nor protected. */
486 public boolean isPackage() {
487 return !testAnyFlags(ALL_ACCESS);
488 }
489 /** Query whether this member has a CallerSensitive annotation. */
490 public boolean isCallerSensitive() {
491 return testAllFlags(CALLER_SENSITIVE);
492 }
493
494 /** Utility method to query whether this member is accessible from a given lookup class. */
495 public boolean isAccessibleFrom(Class<?> lookupClass) {
496 int mode = (ALL_ACCESS|MethodHandles.Lookup.PACKAGE|MethodHandles.Lookup.MODULE);
497 return VerifyAccess.isMemberAccessible(this.getDeclaringClass(), this.getDeclaringClass(), flags,
498 lookupClass, mode);
499 }
500
501 /** Initialize a query. It is not resolved. */
502 private void init(Class<?> defClass, String name, Object type, int flags) {
503 // defining class is allowed to be null (for a naked name/type pair)
504 //name.toString(); // null check
505 //type.equals(type); // null check
506 // fill in fields:
507 this.clazz = defClass;
508 this.name = name;
509 this.type = type;
510 this.flags = flags;
511 assert(testAnyFlags(ALL_KINDS));
512 assert(this.resolution == null); // nobody should have touched this yet
513 //assert(referenceKindIsConsistent()); // do this after resolution
514 }
515
516 /**
517 * Calls down to the VM to fill in the fields. This method is
518 * synchronized to avoid racing calls.
519 */
520 private void expandFromVM() {
521 if (type != null) {
522 return;
523 }
524 if (!isResolved()) {
525 return;
526 }
527 MethodHandleNatives.expand(this);
528 }
529
530 // Capturing information from the Core Reflection API:
531 private static int flagsMods(int flags, int mods, byte refKind) {
532 assert((flags & RECOGNIZED_MODIFIERS) == 0);
533 assert((mods & ~RECOGNIZED_MODIFIERS) == 0);
534 assert((refKind & ~MN_REFERENCE_KIND_MASK) == 0);
535 return flags | mods | (refKind << MN_REFERENCE_KIND_SHIFT);
536 }
537 /** Create a name for the given reflected method. The resulting name will be in a resolved state. */
538 public MemberName(Method m) {
539 this(m, false);
540 }
541 @SuppressWarnings("LeakingThisInConstructor")
542 public MemberName(Method m, boolean wantSpecial) {
543 Objects.requireNonNull(m);
544 // fill in vmtarget, vmindex while we have m in hand:
545 MethodHandleNatives.init(this, m);
546 if (clazz == null) { // MHN.init failed
547 if (m.getDeclaringClass() == MethodHandle.class &&
548 isMethodHandleInvokeName(m.getName())) {
549 // The JVM did not reify this signature-polymorphic instance.
550 // Need a special case here.
551 // See comments on MethodHandleNatives.linkMethod.
552 MethodType type = MethodType.methodType(m.getReturnType(), m.getParameterTypes());
553 int flags = flagsMods(IS_METHOD, m.getModifiers(), REF_invokeVirtual);
554 init(MethodHandle.class, m.getName(), type, flags);
555 if (isMethodHandleInvoke())
556 return;
557 }
558 if (m.getDeclaringClass() == VarHandle.class &&
559 isVarHandleMethodInvokeName(m.getName())) {
560 // The JVM did not reify this signature-polymorphic instance.
561 // Need a special case here.
562 // See comments on MethodHandleNatives.linkMethod.
563 MethodType type = MethodType.methodType(m.getReturnType(), m.getParameterTypes());
564 int flags = flagsMods(IS_METHOD, m.getModifiers(), REF_invokeVirtual);
565 init(VarHandle.class, m.getName(), type, flags);
566 if (isVarHandleMethodInvoke())
567 return;
568 }
569 throw new LinkageError(m.toString());
570 }
571 assert(isResolved() && this.clazz != null);
572 this.name = m.getName();
573 if (this.type == null)
574 this.type = new Object[] { m.getReturnType(), m.getParameterTypes() };
575 if (wantSpecial) {
576 if (isAbstract())
577 throw new AbstractMethodError(this.toString());
578 if (getReferenceKind() == REF_invokeVirtual)
579 changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual);
580 else if (getReferenceKind() == REF_invokeInterface)
581 // invokeSpecial on a default method
582 changeReferenceKind(REF_invokeSpecial, REF_invokeInterface);
583 }
584 }
585 public MemberName asSpecial() {
586 switch (getReferenceKind()) {
587 case REF_invokeSpecial: return this;
588 case REF_invokeVirtual: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual);
589 case REF_invokeInterface: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeInterface);
590 case REF_newInvokeSpecial: return clone().changeReferenceKind(REF_invokeSpecial, REF_newInvokeSpecial);
591 }
592 throw new IllegalArgumentException(this.toString());
593 }
594 /** If this MN is not REF_newInvokeSpecial, return a clone with that ref. kind.
595 * In that case it must already be REF_invokeSpecial.
596 */
597 public MemberName asConstructor() {
598 switch (getReferenceKind()) {
599 case REF_invokeSpecial: return clone().changeReferenceKind(REF_newInvokeSpecial, REF_invokeSpecial);
600 case REF_newInvokeSpecial: return this;
601 }
602 throw new IllegalArgumentException(this.toString());
603 }
604 /** If this MN is a REF_invokeSpecial, return a clone with the "normal" kind
605 * REF_invokeVirtual; also switch either to REF_invokeInterface if clazz.isInterface.
606 * The end result is to get a fully virtualized version of the MN.
607 * (Note that resolving in the JVM will sometimes devirtualize, changing
608 * REF_invokeVirtual of a final to REF_invokeSpecial, and REF_invokeInterface
609 * in some corner cases to either of the previous two; this transform
610 * undoes that change under the assumption that it occurred.)
611 */
612 public MemberName asNormalOriginal() {
613 byte normalVirtual = clazz.isInterface() ? REF_invokeInterface : REF_invokeVirtual;
614 byte refKind = getReferenceKind();
615 byte newRefKind = refKind;
616 MemberName result = this;
617 switch (refKind) {
618 case REF_invokeInterface:
619 case REF_invokeVirtual:
620 case REF_invokeSpecial:
621 newRefKind = normalVirtual;
622 break;
623 }
624 if (newRefKind == refKind)
625 return this;
626 result = clone().changeReferenceKind(newRefKind, refKind);
627 assert(this.referenceKindIsConsistentWith(result.getReferenceKind()));
628 return result;
629 }
630 /** Create a name for the given reflected constructor. The resulting name will be in a resolved state. */
631 @SuppressWarnings("LeakingThisInConstructor")
632 public MemberName(Constructor<?> ctor) {
633 Objects.requireNonNull(ctor);
634 // fill in vmtarget, vmindex while we have ctor in hand:
635 MethodHandleNatives.init(this, ctor);
636 assert(isResolved() && this.clazz != null);
637 this.name = CONSTRUCTOR_NAME;
638 if (this.type == null)
639 this.type = new Object[] { void.class, ctor.getParameterTypes() };
640 }
641 /** Create a name for the given reflected field. The resulting name will be in a resolved state.
642 */
643 public MemberName(Field fld) {
644 this(fld, false);
645 }
646 @SuppressWarnings("LeakingThisInConstructor")
647 public MemberName(Field fld, boolean makeSetter) {
648 Objects.requireNonNull(fld);
649 // fill in vmtarget, vmindex while we have fld in hand:
650 MethodHandleNatives.init(this, fld);
651 assert(isResolved() && this.clazz != null);
652 this.name = fld.getName();
653 this.type = fld.getType();
654 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField));
655 byte refKind = this.getReferenceKind();
656 assert(refKind == (isStatic() ? REF_getStatic : REF_getField));
657 if (makeSetter) {
658 changeReferenceKind((byte)(refKind + (REF_putStatic - REF_getStatic)), refKind);
659 }
660 }
661 public boolean isGetter() {
662 return MethodHandleNatives.refKindIsGetter(getReferenceKind());
663 }
664 public boolean isSetter() {
665 return MethodHandleNatives.refKindIsSetter(getReferenceKind());
666 }
667 public MemberName asSetter() {
668 byte refKind = getReferenceKind();
669 assert(MethodHandleNatives.refKindIsGetter(refKind));
670 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField));
671 byte setterRefKind = (byte)(refKind + (REF_putField - REF_getField));
672 return clone().changeReferenceKind(setterRefKind, refKind);
673 }
674 /** Create a name for the given class. The resulting name will be in a resolved state. */
675 public MemberName(Class<?> type) {
676 init(type.getDeclaringClass(), type.getSimpleName(), type,
677 flagsMods(IS_TYPE, type.getModifiers(), REF_NONE));
678 initResolved(true);
679 }
680
681 /**
682 * Create a name for a signature-polymorphic invoker.
683 * This is a placeholder for a signature-polymorphic instance
684 * (of MH.invokeExact, etc.) that the JVM does not reify.
685 * See comments on {@link MethodHandleNatives#linkMethod}.
686 */
687 static MemberName makeMethodHandleInvoke(String name, MethodType type) {
688 return makeMethodHandleInvoke(name, type, MH_INVOKE_MODS | SYNTHETIC);
689 }
690 static MemberName makeMethodHandleInvoke(String name, MethodType type, int mods) {
691 MemberName mem = new MemberName(MethodHandle.class, name, type, REF_invokeVirtual);
692 mem.flags |= mods; // it's not resolved, but add these modifiers anyway
693 assert(mem.isMethodHandleInvoke()) : mem;
694 return mem;
695 }
696
697 static MemberName makeVarHandleMethodInvoke(String name, MethodType type) {
698 return makeVarHandleMethodInvoke(name, type, MH_INVOKE_MODS | SYNTHETIC);
699 }
700 static MemberName makeVarHandleMethodInvoke(String name, MethodType type, int mods) {
701 MemberName mem = new MemberName(VarHandle.class, name, type, REF_invokeVirtual);
702 mem.flags |= mods; // it's not resolved, but add these modifiers anyway
703 assert(mem.isVarHandleMethodInvoke()) : mem;
704 return mem;
705 }
706
707 // bare-bones constructor; the JVM will fill it in
708 MemberName() { }
709
710 // locally useful cloner
711 @Override protected MemberName clone() {
712 try {
713 return (MemberName) super.clone();
714 } catch (CloneNotSupportedException ex) {
715 throw newInternalError(ex);
716 }
717 }
718
719 /** Get the definition of this member name.
720 * This may be in a super-class of the declaring class of this member.
721 */
722 public MemberName getDefinition() {
723 if (!isResolved()) throw new IllegalStateException("must be resolved: "+this);
724 if (isType()) return this;
725 MemberName res = this.clone();
726 res.clazz = null;
727 res.type = null;
728 res.name = null;
729 res.resolution = res;
730 res.expandFromVM();
731 assert(res.getName().equals(this.getName()));
732 return res;
733 }
734
735 @Override
736 public int hashCode() {
737 // Avoid autoboxing getReferenceKind(), since this is used early and will force
738 // early initialization of Byte$ByteCache
739 return Objects.hash(clazz, new Byte(getReferenceKind()), name, getType());
740 }
741
742 @Override
743 public boolean equals(Object that) {
744 return (that instanceof MemberName && this.equals((MemberName)that));
745 }
746
747 /** Decide if two member names have exactly the same symbolic content.
748 * Does not take into account any actual class members, so even if
749 * two member names resolve to the same actual member, they may
750 * be distinct references.
751 */
752 public boolean equals(MemberName that) {
753 if (this == that) return true;
754 if (that == null) return false;
755 return this.clazz == that.clazz
756 && this.getReferenceKind() == that.getReferenceKind()
757 && Objects.equals(this.name, that.name)
758 && Objects.equals(this.getType(), that.getType());
759 }
760
761 // Construction from symbolic parts, for queries:
762 /** Create a field or type name from the given components:
763 * Declaring class, name, type, reference kind.
764 * The declaring class may be supplied as null if this is to be a bare name and type.
765 * The resulting name will in an unresolved state.
766 */
767 public MemberName(Class<?> defClass, String name, Class<?> type, byte refKind) {
768 init(defClass, name, type, flagsMods(IS_FIELD, 0, refKind));
769 initResolved(false);
770 }
771 /** Create a method or constructor name from the given components:
772 * Declaring class, name, type, reference kind.
773 * It will be a constructor if and only if the name is {@code "<init>"}.
774 * The declaring class may be supplied as null if this is to be a bare name and type.
775 * The last argument is optional, a boolean which requests REF_invokeSpecial.
776 * The resulting name will in an unresolved state.
777 */
778 public MemberName(Class<?> defClass, String name, MethodType type, byte refKind) {
779 int initFlags = (name != null && name.equals(CONSTRUCTOR_NAME) ? IS_CONSTRUCTOR : IS_METHOD);
780 init(defClass, name, type, flagsMods(initFlags, 0, refKind));
781 initResolved(false);
782 }
783 /** Create a method, constructor, or field name from the given components:
784 * Reference kind, declaring class, name, type.
785 */
786 public MemberName(byte refKind, Class<?> defClass, String name, Object type) {
787 int kindFlags;
788 if (MethodHandleNatives.refKindIsField(refKind)) {
789 kindFlags = IS_FIELD;
790 if (!(type instanceof Class))
791 throw newIllegalArgumentException("not a field type");
792 } else if (MethodHandleNatives.refKindIsMethod(refKind)) {
793 kindFlags = IS_METHOD;
794 if (!(type instanceof MethodType))
795 throw newIllegalArgumentException("not a method type");
796 } else if (refKind == REF_newInvokeSpecial) {
797 kindFlags = IS_CONSTRUCTOR;
798 if (!(type instanceof MethodType) ||
799 !CONSTRUCTOR_NAME.equals(name))
800 throw newIllegalArgumentException("not a constructor type or name");
801 } else {
802 throw newIllegalArgumentException("bad reference kind "+refKind);
803 }
804 init(defClass, name, type, flagsMods(kindFlags, 0, refKind));
805 initResolved(false);
806 }
807 /** Query whether this member name is resolved to a non-static, non-final method.
808 */
809 public boolean hasReceiverTypeDispatch() {
810 return MethodHandleNatives.refKindDoesDispatch(getReferenceKind());
811 }
812
813 /** Query whether this member name is resolved.
814 * A resolved member name is one for which the JVM has found
815 * a method, constructor, field, or type binding corresponding exactly to the name.
816 * (Document?)
817 */
818 public boolean isResolved() {
819 return resolution == null;
820 }
821
822 private void initResolved(boolean isResolved) {
823 assert(this.resolution == null); // not initialized yet!
824 if (!isResolved)
825 this.resolution = this;
826 assert(isResolved() == isResolved);
827 }
828
829 void checkForTypeAlias() {
830 if (isInvocable()) {
831 MethodType type;
832 if (this.type instanceof MethodType)
833 type = (MethodType) this.type;
834 else
835 this.type = type = getMethodType();
836 if (type.erase() == type) return;
837 if (VerifyAccess.isTypeVisible(type, clazz)) return;
838 throw new LinkageError("bad method type alias: "+type+" not visible from "+clazz);
839 } else {
840 Class<?> type;
841 if (this.type instanceof Class<?>)
842 type = (Class<?>) this.type;
843 else
844 this.type = type = getFieldType();
845 if (VerifyAccess.isTypeVisible(type, clazz)) return;
846 throw new LinkageError("bad field type alias: "+type+" not visible from "+clazz);
847 }
848 }
849
850
851 /** Produce a string form of this member name.
852 * For types, it is simply the type's own string (as reported by {@code toString}).
853 * For fields, it is {@code "DeclaringClass.name/type"}.
854 * For methods and constructors, it is {@code "DeclaringClass.name(ptype...)rtype"}.
855 * If the declaring class is null, the prefix {@code "DeclaringClass."} is omitted.
856 * If the member is unresolved, a prefix {@code "*."} is prepended.
857 */
858 @SuppressWarnings("LocalVariableHidesMemberVariable")
859 @Override
860 public String toString() {
861 if (isType())
862 return type.toString(); // class java.lang.String
863 // else it is a field, method, or constructor
864 StringBuilder buf = new StringBuilder();
865 if (getDeclaringClass() != null) {
866 buf.append(getName(clazz));
867 buf.append('.');
868 }
869 String name = getName();
870 buf.append(name == null ? "*" : name);
871 Object type = getType();
872 if (!isInvocable()) {
873 buf.append('/');
874 buf.append(type == null ? "*" : getName(type));
875 } else {
876 buf.append(type == null ? "(*)*" : getName(type));
877 }
878 byte refKind = getReferenceKind();
879 if (refKind != REF_NONE) {
880 buf.append('/');
881 buf.append(MethodHandleNatives.refKindName(refKind));
882 }
883 //buf.append("#").append(System.identityHashCode(this));
884 return buf.toString();
885 }
886 private static String getName(Object obj) {
887 if (obj instanceof Class<?>)
888 return ((Class<?>)obj).getName();
889 return String.valueOf(obj);
890 }
891
892 public IllegalAccessException makeAccessException(String message, Object from) {
893 message = message + ": "+ toString();
894 if (from != null) {
895 if (from == MethodHandles.publicLookup()) {
896 message += ", from public Lookup";
897 } else {
898 Module m;
899 if (from instanceof MethodHandles.Lookup) {
900 MethodHandles.Lookup lookup = (MethodHandles.Lookup)from;
901 m = lookup.lookupClass().getModule();
902 } else {
903 m = from.getClass().getModule();
904 }
905 message += ", from " + from + " (" + m + ")";
906 }
907 }
908 return new IllegalAccessException(message);
909 }
910 private String message() {
911 if (isResolved())
912 return "no access";
913 else if (isConstructor())
914 return "no such constructor";
915 else if (isMethod())
916 return "no such method";
917 else
918 return "no such field";
919 }
920 public ReflectiveOperationException makeAccessException() {
921 String message = message() + ": "+ toString();
922 ReflectiveOperationException ex;
923 if (isResolved() || !(resolution instanceof NoSuchMethodError ||
924 resolution instanceof NoSuchFieldError))
925 ex = new IllegalAccessException(message);
926 else if (isConstructor())
927 ex = new NoSuchMethodException(message);
928 else if (isMethod())
929 ex = new NoSuchMethodException(message);
930 else
931 ex = new NoSuchFieldException(message);
932 if (resolution instanceof Throwable)
933 ex.initCause((Throwable) resolution);
934 return ex;
935 }
936
937 /** Actually making a query requires an access check. */
938 /*non-public*/ static Factory getFactory() {
939 return Factory.INSTANCE;
940 }
941 /** A factory type for resolving member names with the help of the VM.
942 * TBD: Define access-safe public constructors for this factory.
943 */
944 /*non-public*/ static class Factory {
945 private Factory() { } // singleton pattern
946 static Factory INSTANCE = new Factory();
947
948 private static int ALLOWED_FLAGS = ALL_KINDS;
949
950 /// Queries
951 List<MemberName> getMembers(Class<?> defc,
952 String matchName, Object matchType,
953 int matchFlags, Class<?> lookupClass) {
954 matchFlags &= ALLOWED_FLAGS;
955 String matchSig = null;
956 if (matchType != null) {
957 matchSig = BytecodeDescriptor.unparse(matchType);
958 if (matchSig.startsWith("("))
959 matchFlags &= ~(ALL_KINDS & ~IS_INVOCABLE);
960 else
961 matchFlags &= ~(ALL_KINDS & ~IS_FIELD);
962 }
963 final int BUF_MAX = 0x2000;
964 int len1 = matchName == null ? 10 : matchType == null ? 4 : 1;
965 MemberName[] buf = newMemberBuffer(len1);
966 int totalCount = 0;
967 ArrayList<MemberName[]> bufs = null;
968 int bufCount = 0;
969 for (;;) {
970 bufCount = MethodHandleNatives.getMembers(defc,
971 matchName, matchSig, matchFlags,
972 lookupClass,
973 totalCount, buf);
974 if (bufCount <= buf.length) {
975 if (bufCount < 0) bufCount = 0;
976 totalCount += bufCount;
977 break;
978 }
979 // JVM returned to us with an intentional overflow!
980 totalCount += buf.length;
981 int excess = bufCount - buf.length;
982 if (bufs == null) bufs = new ArrayList<>(1);
983 bufs.add(buf);
984 int len2 = buf.length;
985 len2 = Math.max(len2, excess);
986 len2 = Math.max(len2, totalCount / 4);
987 buf = newMemberBuffer(Math.min(BUF_MAX, len2));
988 }
989 ArrayList<MemberName> result = new ArrayList<>(totalCount);
990 if (bufs != null) {
991 for (MemberName[] buf0 : bufs) {
992 Collections.addAll(result, buf0);
993 }
994 }
995 result.addAll(Arrays.asList(buf).subList(0, bufCount));
996 // Signature matching is not the same as type matching, since
997 // one signature might correspond to several types.
998 // So if matchType is a Class or MethodType, refilter the results.
999 if (matchType != null && matchType != matchSig) {
1000 for (Iterator<MemberName> it = result.iterator(); it.hasNext();) {
1001 MemberName m = it.next();
1002 if (!matchType.equals(m.getType()))
1003 it.remove();
1004 }
1005 }
1006 return result;
1007 }
1008 /** Produce a resolved version of the given member.
1009 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1010 * Access checking is performed on behalf of the given {@code lookupClass}.
1011 * If lookup fails or access is not permitted, null is returned.
1012 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in.
1013 */
1014 private MemberName resolve(byte refKind, MemberName ref, Class<?> lookupClass) {
1015 MemberName m = ref.clone(); // JVM will side-effect the ref
1016 assert(refKind == m.getReferenceKind());
1017 try {
1018 m = MethodHandleNatives.resolve(m, lookupClass);
1019 m.checkForTypeAlias();
1020 m.resolution = null;
1021 } catch (LinkageError ex) {
1022 // JVM reports that the "bytecode behavior" would get an error
1023 assert(!m.isResolved());
1024 m.resolution = ex;
1025 return m;
1026 }
1027 assert(m.referenceKindIsConsistent());
1028 m.initResolved(true);
1029 assert(m.vminfoIsConsistent());
1030 return m;
1031 }
1032 /** Produce a resolved version of the given member.
1033 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1034 * Access checking is performed on behalf of the given {@code lookupClass}.
1035 * If lookup fails or access is not permitted, a {@linkplain ReflectiveOperationException} is thrown.
1036 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in.
1037 */
1038 public
1039 <NoSuchMemberException extends ReflectiveOperationException>
1040 MemberName resolveOrFail(byte refKind, MemberName m, Class<?> lookupClass,
1041 Class<NoSuchMemberException> nsmClass)
1042 throws IllegalAccessException, NoSuchMemberException {
1043 MemberName result = resolve(refKind, m, lookupClass);
1044 if (result.isResolved())
1045 return result;
1046 ReflectiveOperationException ex = result.makeAccessException();
1047 if (ex instanceof IllegalAccessException) throw (IllegalAccessException) ex;
1048 throw nsmClass.cast(ex);
1049 }
1050 /** Produce a resolved version of the given member.
1051 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1052 * Access checking is performed on behalf of the given {@code lookupClass}.
1053 * If lookup fails or access is not permitted, return null.
1054 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in.
1055 */
1056 public
1057 MemberName resolveOrNull(byte refKind, MemberName m, Class<?> lookupClass) {
1058 MemberName result = resolve(refKind, m, lookupClass);
1059 if (result.isResolved())
1060 return result;
1061 return null;
1062 }
1063 /** Return a list of all methods defined by the given class.
1064 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1065 * Access checking is performed on behalf of the given {@code lookupClass}.
1066 * Inaccessible members are not added to the last.
1067 */
1068 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers,
1069 Class<?> lookupClass) {
1070 return getMethods(defc, searchSupers, null, null, lookupClass);
1071 }
1072 /** Return a list of matching methods defined by the given class.
1073 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1074 * Returned methods will match the name (if not null) and the type (if not null).
1075 * Access checking is performed on behalf of the given {@code lookupClass}.
1076 * Inaccessible members are not added to the last.
1077 */
1078 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers,
1079 String name, MethodType type, Class<?> lookupClass) {
1080 int matchFlags = IS_METHOD | (searchSupers ? SEARCH_ALL_SUPERS : 0);
1081 return getMembers(defc, name, type, matchFlags, lookupClass);
1082 }
1083 /** Return a list of all constructors defined by the given class.
1084 * Access checking is performed on behalf of the given {@code lookupClass}.
1085 * Inaccessible members are not added to the last.
1086 */
1087 public List<MemberName> getConstructors(Class<?> defc, Class<?> lookupClass) {
1088 return getMembers(defc, null, null, IS_CONSTRUCTOR, lookupClass);
1089 }
1090 /** Return a list of all fields defined by the given class.
1091 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1092 * Access checking is performed on behalf of the given {@code lookupClass}.
1093 * Inaccessible members are not added to the last.
1094 */
1095 public List<MemberName> getFields(Class<?> defc, boolean searchSupers,
1096 Class<?> lookupClass) {
1097 return getFields(defc, searchSupers, null, null, lookupClass);
1098 }
1099 /** Return a list of all fields defined by the given class.
1100 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1101 * Returned fields will match the name (if not null) and the type (if not null).
1102 * Access checking is performed on behalf of the given {@code lookupClass}.
1103 * Inaccessible members are not added to the last.
1104 */
1105 public List<MemberName> getFields(Class<?> defc, boolean searchSupers,
1106 String name, Class<?> type, Class<?> lookupClass) {
1107 int matchFlags = IS_FIELD | (searchSupers ? SEARCH_ALL_SUPERS : 0);
1108 return getMembers(defc, name, type, matchFlags, lookupClass);
1109 }
1110 /** Return a list of all nested types defined by the given class.
1111 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1112 * Access checking is performed on behalf of the given {@code lookupClass}.
1113 * Inaccessible members are not added to the last.
1114 */
1115 public List<MemberName> getNestedTypes(Class<?> defc, boolean searchSupers,
1116 Class<?> lookupClass) {
1117 int matchFlags = IS_TYPE | (searchSupers ? SEARCH_ALL_SUPERS : 0);
1118 return getMembers(defc, null, null, matchFlags, lookupClass);
1119 }
1120 private static MemberName[] newMemberBuffer(int length) {
1121 MemberName[] buf = new MemberName[length];
1122 // fill the buffer with dummy structs for the JVM to fill in
1123 for (int i = 0; i < length; i++)
1124 buf[i] = new MemberName();
1125 return buf;
1126 }
1127 }
1128
1129 static {
1130 // Allow privileged classes outside of java.lang
1131 jdk.internal.misc.SharedSecrets.setJavaLangInvokeAccess(new jdk.internal.misc.JavaLangInvokeAccess() {
1132 public Object newMemberName() {
1133 return new MemberName();
1134 }
1135 public String getName(Object mname) {
1136 MemberName memberName = (MemberName)mname;
1137 return memberName.getName();
1138 }
1139 });
1140 }
1141 }