1 /*
2 * Copyright (c) 2008, 2016, 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 jdk.internal.misc.JavaLangInvokeAccess;
29 import jdk.internal.misc.SharedSecrets;
30 import sun.invoke.util.BytecodeDescriptor;
31 import sun.invoke.util.VerifyAccess;
32
33 import java.lang.reflect.Constructor;
34 import java.lang.reflect.Field;
35 import java.lang.reflect.Member;
36 import java.lang.reflect.Method;
37 import java.lang.reflect.Modifier;
38 import java.lang.reflect.Module;
39 import java.util.ArrayList;
40 import java.util.Arrays;
41 import java.util.Collections;
42 import java.util.Iterator;
43 import java.util.List;
44 import java.util.Objects;
45
46 import static java.lang.invoke.MethodHandleNatives.Constants.*;
47 import static java.lang.invoke.MethodHandleStatics.newIllegalArgumentException;
48 import static java.lang.invoke.MethodHandleStatics.newInternalError;
49
50 /**
51 * A {@code MemberName} is a compact symbolic datum which fully characterizes
52 * a method or field reference.
53 * A member name refers to a field, method, constructor, or member type.
54 * Every member name has a simple name (a string) and a type (either a Class or MethodType).
55 * A member name may also have a non-null declaring class, or it may be simply
56 * a naked name/type pair.
57 * A member name may also have non-zero modifier flags.
58 * Finally, a member name may be either resolved or unresolved.
59 * If it is resolved, the existence of the named member has been determined by the JVM.
60 * <p>
61 * Whether resolved or not, a member name provides no access rights or
62 * invocation capability to its possessor. It is merely a compact
63 * representation of all symbolic information necessary to link to
64 * and properly use the named member.
65 * <p>
66 * When resolved, a member name's internal implementation may include references to JVM metadata.
67 * This representation is stateless and only descriptive.
68 * It provides no private information and no capability to use the member.
69 * <p>
70 * By contrast, a {@linkplain java.lang.reflect.Method} contains fuller information
71 * about the internals of a method (except its bytecodes) and also
72 * allows invocation. A MemberName is much lighter than a Method,
73 * since it contains about 7 fields to the 16 of Method (plus its sub-arrays),
74 * and those seven fields omit much of the information in Method.
75 * @author jrose
76 */
77 /*non-public*/ final class MemberName implements Member, Cloneable {
78 private Class<?> clazz; // class in which the method is defined
79 private String name; // may be null if not yet materialized
80 private Object type; // may be null if not yet materialized
81 private int flags; // modifier bits; see reflect.Modifier
82 //@Injected JVM_Method* vmtarget;
83 //@Injected int vmindex;
84 private Object resolution; // if null, this guy is resolved
85
86 /** Return the declaring class of this member.
87 * In the case of a bare name and type, the declaring class will be null.
88 */
89 public Class<?> getDeclaringClass() {
90 return clazz;
91 }
92
93 /** Utility method producing the class loader of the declaring class. */
94 public ClassLoader getClassLoader() {
95 return clazz.getClassLoader();
96 }
97
98 /** Return the simple name of this member.
99 * For a type, it is the same as {@link Class#getSimpleName}.
100 * For a method or field, it is the simple name of the member.
101 * For a constructor, it is always {@code "<init>"}.
102 */
103 public String getName() {
104 if (name == null) {
105 expandFromVM();
106 if (name == null) {
107 return null;
108 }
109 }
110 return name;
111 }
112
113 public MethodType getMethodOrFieldType() {
114 if (isInvocable())
115 return getMethodType();
116 if (isGetter())
117 return MethodType.methodType(getFieldType());
118 if (isSetter())
119 return MethodType.methodType(void.class, getFieldType());
120 throw new InternalError("not a method or field: "+this);
121 }
122
123 /** Return the declared type of this member, which
124 * must be a method or constructor.
125 */
126 public MethodType getMethodType() {
127 if (type == null) {
128 expandFromVM();
129 if (type == null) {
130 return null;
131 }
132 }
133 if (!isInvocable()) {
134 throw newIllegalArgumentException("not invocable, no method type");
135 }
136
137 {
138 // Get a snapshot of type which doesn't get changed by racing threads.
139 final Object type = this.type;
140 if (type instanceof MethodType) {
141 return (MethodType) type;
142 }
143 }
144
145 // type is not a MethodType yet. Convert it thread-safely.
146 synchronized (this) {
147 if (type instanceof String) {
148 String sig = (String) type;
149 MethodType res = MethodType.fromDescriptor(sig, getClassLoader());
150 type = res;
151 } else if (type instanceof Object[]) {
152 Object[] typeInfo = (Object[]) type;
153 Class<?>[] ptypes = (Class<?>[]) typeInfo[1];
154 Class<?> rtype = (Class<?>) typeInfo[0];
155 MethodType res = MethodType.methodType(rtype, ptypes);
156 type = res;
157 }
158 // Make sure type is a MethodType for racing threads.
159 assert type instanceof MethodType : "bad method type " + type;
160 }
161 return (MethodType) type;
162 }
163
164 /** Return the actual type under which this method or constructor must be invoked.
165 * For non-static methods or constructors, this is the type with a leading parameter,
166 * a reference to declaring class. For static methods, it is the same as the declared type.
167 */
168 public MethodType getInvocationType() {
169 MethodType itype = getMethodOrFieldType();
170 if (isConstructor() && getReferenceKind() == REF_newInvokeSpecial)
171 return itype.changeReturnType(clazz);
172 if (!isStatic())
173 return itype.insertParameterTypes(0, clazz);
174 return itype;
175 }
176
177 /** Utility method producing the parameter types of the method type. */
178 public Class<?>[] getParameterTypes() {
179 return getMethodType().parameterArray();
180 }
181
182 /** Utility method producing the return type of the method type. */
183 public Class<?> getReturnType() {
184 return getMethodType().returnType();
185 }
186
187 /** Return the declared type of this member, which
188 * must be a field or type.
189 * If it is a type member, that type itself is returned.
190 */
191 public Class<?> getFieldType() {
192 if (type == null) {
193 expandFromVM();
194 if (type == null) {
195 return null;
196 }
197 }
198 if (isInvocable()) {
199 throw newIllegalArgumentException("not a field or nested class, no simple type");
200 }
201
202 {
203 // Get a snapshot of type which doesn't get changed by racing threads.
204 final Object type = this.type;
205 if (type instanceof Class<?>) {
206 return (Class<?>) type;
207 }
208 }
209
210 // type is not a Class yet. Convert it thread-safely.
211 synchronized (this) {
212 if (type instanceof String) {
213 String sig = (String) type;
214 MethodType mtype = MethodType.fromDescriptor("()"+sig, getClassLoader());
215 Class<?> res = mtype.returnType();
216 type = res;
217 }
218 // Make sure type is a Class for racing threads.
219 assert type instanceof Class<?> : "bad field type " + type;
220 }
221 return (Class<?>) type;
222 }
223
224 /** Utility method to produce either the method type or field type of this member. */
225 public Object getType() {
226 return (isInvocable() ? getMethodType() : getFieldType());
227 }
228
229 /** Utility method to produce the signature of this member,
230 * used within the class file format to describe its type.
231 */
232 public String getSignature() {
233 if (type == null) {
234 expandFromVM();
235 if (type == null) {
236 return null;
237 }
238 }
239 if (isInvocable())
240 return BytecodeDescriptor.unparse(getMethodType());
241 else
242 return BytecodeDescriptor.unparse(getFieldType());
243 }
244
245 /** Return the modifier flags of this member.
246 * @see java.lang.reflect.Modifier
247 */
248 public int getModifiers() {
249 return (flags & RECOGNIZED_MODIFIERS);
250 }
251
252 /** Return the reference kind of this member, or zero if none.
253 */
254 public byte getReferenceKind() {
255 return (byte) ((flags >>> MN_REFERENCE_KIND_SHIFT) & MN_REFERENCE_KIND_MASK);
256 }
257 private boolean referenceKindIsConsistent() {
258 byte refKind = getReferenceKind();
259 if (refKind == REF_NONE) return isType();
260 if (isField()) {
261 assert(staticIsConsistent());
262 assert(MethodHandleNatives.refKindIsField(refKind));
263 } else if (isConstructor()) {
264 assert(refKind == REF_newInvokeSpecial || refKind == REF_invokeSpecial);
265 } else if (isMethod()) {
266 assert(staticIsConsistent());
267 assert(MethodHandleNatives.refKindIsMethod(refKind));
268 if (clazz.isInterface())
269 assert(refKind == REF_invokeInterface ||
270 refKind == REF_invokeStatic ||
271 refKind == REF_invokeSpecial ||
272 refKind == REF_invokeVirtual && isObjectPublicMethod());
273 } else {
274 assert(false);
275 }
276 return true;
277 }
278 private boolean isObjectPublicMethod() {
279 if (clazz == Object.class) return true;
280 MethodType mtype = getMethodType();
281 if (name.equals("toString") && mtype.returnType() == String.class && mtype.parameterCount() == 0)
282 return true;
283 if (name.equals("hashCode") && mtype.returnType() == int.class && mtype.parameterCount() == 0)
284 return true;
285 if (name.equals("equals") && mtype.returnType() == boolean.class && mtype.parameterCount() == 1 && mtype.parameterType(0) == Object.class)
286 return true;
287 return false;
288 }
289 /*non-public*/ boolean referenceKindIsConsistentWith(int originalRefKind) {
290 int refKind = getReferenceKind();
291 if (refKind == originalRefKind) return true;
292 switch (originalRefKind) {
293 case REF_invokeInterface:
294 // Looking up an interface method, can get (e.g.) Object.hashCode
295 assert(refKind == REF_invokeVirtual ||
296 refKind == REF_invokeSpecial) : this;
297 return true;
298 case REF_invokeVirtual:
299 case REF_newInvokeSpecial:
300 // Looked up a virtual, can get (e.g.) final String.hashCode.
301 assert(refKind == REF_invokeSpecial) : this;
302 return true;
303 }
304 assert(false) : this+" != "+MethodHandleNatives.refKindName((byte)originalRefKind);
305 return true;
306 }
307 private boolean staticIsConsistent() {
308 byte refKind = getReferenceKind();
309 return MethodHandleNatives.refKindIsStatic(refKind) == isStatic() || getModifiers() == 0;
310 }
311 private boolean vminfoIsConsistent() {
312 byte refKind = getReferenceKind();
313 assert(isResolved()); // else don't call
314 Object vminfo = MethodHandleNatives.getMemberVMInfo(this);
315 assert(vminfo instanceof Object[]);
316 long vmindex = (Long) ((Object[])vminfo)[0];
317 Object vmtarget = ((Object[])vminfo)[1];
318 if (MethodHandleNatives.refKindIsField(refKind)) {
319 assert(vmindex >= 0) : vmindex + ":" + this;
320 assert(vmtarget instanceof Class);
321 } else {
322 if (MethodHandleNatives.refKindDoesDispatch(refKind))
323 assert(vmindex >= 0) : vmindex + ":" + this;
324 else
325 assert(vmindex < 0) : vmindex;
326 assert(vmtarget instanceof MemberName) : vmtarget + " in " + this;
327 }
328 return true;
329 }
330
331 private MemberName changeReferenceKind(byte refKind, byte oldKind) {
332 assert(getReferenceKind() == oldKind);
333 assert(MethodHandleNatives.refKindIsValid(refKind));
334 flags += (((int)refKind - oldKind) << MN_REFERENCE_KIND_SHIFT);
335 return this;
336 }
337
338 private boolean testFlags(int mask, int value) {
339 return (flags & mask) == value;
340 }
341 private boolean testAllFlags(int mask) {
342 return testFlags(mask, mask);
343 }
344 private boolean testAnyFlags(int mask) {
345 return !testFlags(mask, 0);
346 }
347
348 /** Utility method to query if this member is a method handle invocation (invoke or invokeExact).
349 */
350 public boolean isMethodHandleInvoke() {
351 final int bits = MH_INVOKE_MODS &~ Modifier.PUBLIC;
352 final int negs = Modifier.STATIC;
353 if (testFlags(bits | negs, bits) &&
354 clazz == MethodHandle.class) {
355 return isMethodHandleInvokeName(name);
356 }
357 return false;
358 }
359 public static boolean isMethodHandleInvokeName(String name) {
360 switch (name) {
361 case "invoke":
362 case "invokeExact":
363 return true;
364 default:
365 return false;
366 }
367 }
368 public boolean isVarHandleMethodInvoke() {
369 final int bits = MH_INVOKE_MODS &~ Modifier.PUBLIC;
370 final int negs = Modifier.STATIC;
371 if (testFlags(bits | negs, bits) &&
372 clazz == VarHandle.class) {
373 return isVarHandleMethodInvokeName(name);
374 }
375 return false;
376 }
377 public static boolean isVarHandleMethodInvokeName(String name) {
378 try {
379 VarHandle.AccessMode.valueFromMethodName(name);
380 return true;
381 } catch (IllegalArgumentException e) {
382 return false;
383 }
384 }
385 private static final int MH_INVOKE_MODS = Modifier.NATIVE | Modifier.FINAL | Modifier.PUBLIC;
386
387 /** Utility method to query the modifier flags of this member. */
388 public boolean isStatic() {
389 return Modifier.isStatic(flags);
390 }
391 /** Utility method to query the modifier flags of this member. */
392 public boolean isPublic() {
393 return Modifier.isPublic(flags);
394 }
395 /** Utility method to query the modifier flags of this member. */
396 public boolean isPrivate() {
397 return Modifier.isPrivate(flags);
398 }
399 /** Utility method to query the modifier flags of this member. */
400 public boolean isProtected() {
401 return Modifier.isProtected(flags);
402 }
403 /** Utility method to query the modifier flags of this member. */
404 public boolean isFinal() {
405 return Modifier.isFinal(flags);
406 }
407 /** Utility method to query whether this member or its defining class is final. */
408 public boolean canBeStaticallyBound() {
409 return Modifier.isFinal(flags | clazz.getModifiers());
410 }
411 /** Utility method to query the modifier flags of this member. */
412 public boolean isVolatile() {
413 return Modifier.isVolatile(flags);
414 }
415 /** Utility method to query the modifier flags of this member. */
416 public boolean isAbstract() {
417 return Modifier.isAbstract(flags);
418 }
419 /** Utility method to query the modifier flags of this member. */
420 public boolean isNative() {
421 return Modifier.isNative(flags);
422 }
423 // let the rest (native, volatile, transient, etc.) be tested via Modifier.isFoo
424
425 // unofficial modifier flags, used by HotSpot:
426 static final int BRIDGE = 0x00000040;
427 static final int VARARGS = 0x00000080;
428 static final int SYNTHETIC = 0x00001000;
429 static final int ANNOTATION= 0x00002000;
430 static final int ENUM = 0x00004000;
431 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */
432 public boolean isBridge() {
433 return testAllFlags(IS_METHOD | BRIDGE);
434 }
435 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */
436 public boolean isVarargs() {
437 return testAllFlags(VARARGS) && isInvocable();
438 }
439 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */
440 public boolean isSynthetic() {
441 return testAllFlags(SYNTHETIC);
442 }
443
444 static final String CONSTRUCTOR_NAME = "<init>"; // the ever-popular
445
446 // modifiers exported by the JVM:
447 static final int RECOGNIZED_MODIFIERS = 0xFFFF;
448
449 // private flags, not part of RECOGNIZED_MODIFIERS:
450 static final int
451 IS_METHOD = MN_IS_METHOD, // method (not constructor)
452 IS_CONSTRUCTOR = MN_IS_CONSTRUCTOR, // constructor
453 IS_FIELD = MN_IS_FIELD, // field
454 IS_TYPE = MN_IS_TYPE, // nested type
455 CALLER_SENSITIVE = MN_CALLER_SENSITIVE; // @CallerSensitive annotation detected
456
457 static final int ALL_ACCESS = Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED;
458 static final int ALL_KINDS = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE;
459 static final int IS_INVOCABLE = IS_METHOD | IS_CONSTRUCTOR;
460 static final int IS_FIELD_OR_METHOD = IS_METHOD | IS_FIELD;
461 static final int SEARCH_ALL_SUPERS = MN_SEARCH_SUPERCLASSES | MN_SEARCH_INTERFACES;
462
463 /** Utility method to query whether this member is a method or constructor. */
464 public boolean isInvocable() {
465 return testAnyFlags(IS_INVOCABLE);
466 }
467 /** Utility method to query whether this member is a method, constructor, or field. */
468 public boolean isFieldOrMethod() {
469 return testAnyFlags(IS_FIELD_OR_METHOD);
470 }
471 /** Query whether this member is a method. */
472 public boolean isMethod() {
473 return testAllFlags(IS_METHOD);
474 }
475 /** Query whether this member is a constructor. */
476 public boolean isConstructor() {
477 return testAllFlags(IS_CONSTRUCTOR);
478 }
479 /** Query whether this member is a field. */
480 public boolean isField() {
481 return testAllFlags(IS_FIELD);
482 }
483 /** Query whether this member is a type. */
484 public boolean isType() {
485 return testAllFlags(IS_TYPE);
486 }
487 /** Utility method to query whether this member is neither public, private, nor protected. */
488 public boolean isPackage() {
489 return !testAnyFlags(ALL_ACCESS);
490 }
491 /** Query whether this member has a CallerSensitive annotation. */
492 public boolean isCallerSensitive() {
493 return testAllFlags(CALLER_SENSITIVE);
494 }
495
496 /** Utility method to query whether this member is accessible from a given lookup class. */
497 public boolean isAccessibleFrom(Class<?> lookupClass) {
498 int mode = (ALL_ACCESS|MethodHandles.Lookup.PACKAGE|MethodHandles.Lookup.MODULE);
499 return VerifyAccess.isMemberAccessible(this.getDeclaringClass(), this.getDeclaringClass(), flags,
500 lookupClass, mode);
501 }
502
503 /**
504 * Check if MemberName is a call to a method named {@code name} in class {@code declaredClass}.
505 */
506 public boolean refersTo(Class<?> declc, String n) {
507 return clazz == declc && getName().equals(n);
508 }
509
510 /** Initialize a query. It is not resolved. */
511 private void init(Class<?> defClass, String name, Object type, int flags) {
512 // defining class is allowed to be null (for a naked name/type pair)
513 //name.toString(); // null check
514 //type.equals(type); // null check
515 // fill in fields:
516 this.clazz = defClass;
517 this.name = name;
518 this.type = type;
519 this.flags = flags;
520 assert(testAnyFlags(ALL_KINDS));
521 assert(this.resolution == null); // nobody should have touched this yet
522 //assert(referenceKindIsConsistent()); // do this after resolution
523 }
524
525 /**
526 * Calls down to the VM to fill in the fields. This method is
527 * synchronized to avoid racing calls.
528 */
529 private void expandFromVM() {
530 if (type != null) {
531 return;
532 }
533 if (!isResolved()) {
534 return;
535 }
536 MethodHandleNatives.expand(this);
537 }
538
539 // Capturing information from the Core Reflection API:
540 private static int flagsMods(int flags, int mods, byte refKind) {
541 assert((flags & RECOGNIZED_MODIFIERS) == 0);
542 assert((mods & ~RECOGNIZED_MODIFIERS) == 0);
543 assert((refKind & ~MN_REFERENCE_KIND_MASK) == 0);
544 return flags | mods | (refKind << MN_REFERENCE_KIND_SHIFT);
545 }
546 /** Create a name for the given reflected method. The resulting name will be in a resolved state. */
547 public MemberName(Method m) {
548 this(m, false);
549 }
550 @SuppressWarnings("LeakingThisInConstructor")
551 public MemberName(Method m, boolean wantSpecial) {
552 Objects.requireNonNull(m);
553 // fill in vmtarget, vmindex while we have m in hand:
554 MethodHandleNatives.init(this, m);
555 if (clazz == null) { // MHN.init failed
556 if (m.getDeclaringClass() == MethodHandle.class &&
557 isMethodHandleInvokeName(m.getName())) {
558 // The JVM did not reify this signature-polymorphic instance.
559 // Need a special case here.
560 // See comments on MethodHandleNatives.linkMethod.
561 MethodType type = MethodType.methodType(m.getReturnType(), m.getParameterTypes());
562 int flags = flagsMods(IS_METHOD, m.getModifiers(), REF_invokeVirtual);
563 init(MethodHandle.class, m.getName(), type, flags);
564 if (isMethodHandleInvoke())
565 return;
566 }
567 if (m.getDeclaringClass() == VarHandle.class &&
568 isVarHandleMethodInvokeName(m.getName())) {
569 // The JVM did not reify this signature-polymorphic instance.
570 // Need a special case here.
571 // See comments on MethodHandleNatives.linkMethod.
572 MethodType type = MethodType.methodType(m.getReturnType(), m.getParameterTypes());
573 int flags = flagsMods(IS_METHOD, m.getModifiers(), REF_invokeVirtual);
574 init(VarHandle.class, m.getName(), type, flags);
575 if (isVarHandleMethodInvoke())
576 return;
577 }
578 throw new LinkageError(m.toString());
579 }
580 assert(isResolved() && this.clazz != null);
581 this.name = m.getName();
582 if (this.type == null)
583 this.type = new Object[] { m.getReturnType(), m.getParameterTypes() };
584 if (wantSpecial) {
585 if (isAbstract())
586 throw new AbstractMethodError(this.toString());
587 if (getReferenceKind() == REF_invokeVirtual)
588 changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual);
589 else if (getReferenceKind() == REF_invokeInterface)
590 // invokeSpecial on a default method
591 changeReferenceKind(REF_invokeSpecial, REF_invokeInterface);
592 }
593 }
594 public MemberName asSpecial() {
595 switch (getReferenceKind()) {
596 case REF_invokeSpecial: return this;
597 case REF_invokeVirtual: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual);
598 case REF_invokeInterface: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeInterface);
599 case REF_newInvokeSpecial: return clone().changeReferenceKind(REF_invokeSpecial, REF_newInvokeSpecial);
600 }
601 throw new IllegalArgumentException(this.toString());
602 }
603 /** If this MN is not REF_newInvokeSpecial, return a clone with that ref. kind.
604 * In that case it must already be REF_invokeSpecial.
605 */
606 public MemberName asConstructor() {
607 switch (getReferenceKind()) {
608 case REF_invokeSpecial: return clone().changeReferenceKind(REF_newInvokeSpecial, REF_invokeSpecial);
609 case REF_newInvokeSpecial: return this;
610 }
611 throw new IllegalArgumentException(this.toString());
612 }
613 /** If this MN is a REF_invokeSpecial, return a clone with the "normal" kind
614 * REF_invokeVirtual; also switch either to REF_invokeInterface if clazz.isInterface.
615 * The end result is to get a fully virtualized version of the MN.
616 * (Note that resolving in the JVM will sometimes devirtualize, changing
617 * REF_invokeVirtual of a final to REF_invokeSpecial, and REF_invokeInterface
618 * in some corner cases to either of the previous two; this transform
619 * undoes that change under the assumption that it occurred.)
620 */
621 public MemberName asNormalOriginal() {
622 byte normalVirtual = clazz.isInterface() ? REF_invokeInterface : REF_invokeVirtual;
623 byte refKind = getReferenceKind();
624 byte newRefKind = refKind;
625 MemberName result = this;
626 switch (refKind) {
627 case REF_invokeInterface:
628 case REF_invokeVirtual:
629 case REF_invokeSpecial:
630 newRefKind = normalVirtual;
631 break;
632 }
633 if (newRefKind == refKind)
634 return this;
635 result = clone().changeReferenceKind(newRefKind, refKind);
636 assert(this.referenceKindIsConsistentWith(result.getReferenceKind()));
637 return result;
638 }
639 /** Create a name for the given reflected constructor. The resulting name will be in a resolved state. */
640 @SuppressWarnings("LeakingThisInConstructor")
641 public MemberName(Constructor<?> ctor) {
642 Objects.requireNonNull(ctor);
643 // fill in vmtarget, vmindex while we have ctor in hand:
644 MethodHandleNatives.init(this, ctor);
645 assert(isResolved() && this.clazz != null);
646 this.name = CONSTRUCTOR_NAME;
647 if (this.type == null)
648 this.type = new Object[] { void.class, ctor.getParameterTypes() };
649 }
650 /** Create a name for the given reflected field. The resulting name will be in a resolved state.
651 */
652 public MemberName(Field fld) {
653 this(fld, false);
654 }
655 @SuppressWarnings("LeakingThisInConstructor")
656 public MemberName(Field fld, boolean makeSetter) {
657 Objects.requireNonNull(fld);
658 // fill in vmtarget, vmindex while we have fld in hand:
659 MethodHandleNatives.init(this, fld);
660 assert(isResolved() && this.clazz != null);
661 this.name = fld.getName();
662 this.type = fld.getType();
663 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField));
664 byte refKind = this.getReferenceKind();
665 assert(refKind == (isStatic() ? REF_getStatic : REF_getField));
666 if (makeSetter) {
667 changeReferenceKind((byte)(refKind + (REF_putStatic - REF_getStatic)), refKind);
668 }
669 }
670 public boolean isGetter() {
671 return MethodHandleNatives.refKindIsGetter(getReferenceKind());
672 }
673 public boolean isSetter() {
674 return MethodHandleNatives.refKindIsSetter(getReferenceKind());
675 }
676 public MemberName asSetter() {
677 byte refKind = getReferenceKind();
678 assert(MethodHandleNatives.refKindIsGetter(refKind));
679 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField));
680 byte setterRefKind = (byte)(refKind + (REF_putField - REF_getField));
681 return clone().changeReferenceKind(setterRefKind, refKind);
682 }
683 /** Create a name for the given class. The resulting name will be in a resolved state. */
684 public MemberName(Class<?> type) {
685 init(type.getDeclaringClass(), type.getSimpleName(), type,
686 flagsMods(IS_TYPE, type.getModifiers(), REF_NONE));
687 initResolved(true);
688 }
689
690 /**
691 * Create a name for a signature-polymorphic invoker.
692 * This is a placeholder for a signature-polymorphic instance
693 * (of MH.invokeExact, etc.) that the JVM does not reify.
694 * See comments on {@link MethodHandleNatives#linkMethod}.
695 */
696 static MemberName makeMethodHandleInvoke(String name, MethodType type) {
697 return makeMethodHandleInvoke(name, type, MH_INVOKE_MODS | SYNTHETIC);
698 }
699 static MemberName makeMethodHandleInvoke(String name, MethodType type, int mods) {
700 MemberName mem = new MemberName(MethodHandle.class, name, type, REF_invokeVirtual);
701 mem.flags |= mods; // it's not resolved, but add these modifiers anyway
702 assert(mem.isMethodHandleInvoke()) : mem;
703 return mem;
704 }
705
706 static MemberName makeVarHandleMethodInvoke(String name, MethodType type) {
707 return makeVarHandleMethodInvoke(name, type, MH_INVOKE_MODS | SYNTHETIC);
708 }
709 static MemberName makeVarHandleMethodInvoke(String name, MethodType type, int mods) {
710 MemberName mem = new MemberName(VarHandle.class, name, type, REF_invokeVirtual);
711 mem.flags |= mods; // it's not resolved, but add these modifiers anyway
712 assert(mem.isVarHandleMethodInvoke()) : mem;
713 return mem;
714 }
715
716 // bare-bones constructor; the JVM will fill it in
717 MemberName() { }
718
719 // locally useful cloner
720 @Override protected MemberName clone() {
721 try {
722 return (MemberName) super.clone();
723 } catch (CloneNotSupportedException ex) {
724 throw newInternalError(ex);
725 }
726 }
727
728 /** Get the definition of this member name.
729 * This may be in a super-class of the declaring class of this member.
730 */
731 public MemberName getDefinition() {
732 if (!isResolved()) throw new IllegalStateException("must be resolved: "+this);
733 if (isType()) return this;
734 MemberName res = this.clone();
735 res.clazz = null;
736 res.type = null;
737 res.name = null;
738 res.resolution = res;
739 res.expandFromVM();
740 assert(res.getName().equals(this.getName()));
741 return res;
742 }
743
744 @Override
745 @SuppressWarnings("deprecation")
746 public int hashCode() {
747 // Avoid autoboxing getReferenceKind(), since this is used early and will force
748 // early initialization of Byte$ByteCache
749 return Objects.hash(clazz, new Byte(getReferenceKind()), name, getType());
750 }
751
752 @Override
753 public boolean equals(Object that) {
754 return (that instanceof MemberName && this.equals((MemberName)that));
755 }
756
757 /** Decide if two member names have exactly the same symbolic content.
758 * Does not take into account any actual class members, so even if
759 * two member names resolve to the same actual member, they may
760 * be distinct references.
761 */
762 public boolean equals(MemberName that) {
763 if (this == that) return true;
764 if (that == null) return false;
765 return this.clazz == that.clazz
766 && this.getReferenceKind() == that.getReferenceKind()
767 && Objects.equals(this.name, that.name)
768 && Objects.equals(this.getType(), that.getType());
769 }
770
771 // Construction from symbolic parts, for queries:
772 /** Create a field or type name from the given components:
773 * Declaring class, name, type, reference kind.
774 * The declaring class may be supplied as null if this is to be a bare name and type.
775 * The resulting name will in an unresolved state.
776 */
777 public MemberName(Class<?> defClass, String name, Class<?> type, byte refKind) {
778 init(defClass, name, type, flagsMods(IS_FIELD, 0, refKind));
779 initResolved(false);
780 }
781 /** Create a method or constructor name from the given components:
782 * Declaring class, name, type, reference kind.
783 * It will be a constructor if and only if the name is {@code "<init>"}.
784 * The declaring class may be supplied as null if this is to be a bare name and type.
785 * The last argument is optional, a boolean which requests REF_invokeSpecial.
786 * The resulting name will in an unresolved state.
787 */
788 public MemberName(Class<?> defClass, String name, MethodType type, byte refKind) {
789 int initFlags = (name != null && name.equals(CONSTRUCTOR_NAME) ? IS_CONSTRUCTOR : IS_METHOD);
790 init(defClass, name, type, flagsMods(initFlags, 0, refKind));
791 initResolved(false);
792 }
793 /** Create a method, constructor, or field name from the given components:
794 * Reference kind, declaring class, name, type.
795 */
796 public MemberName(byte refKind, Class<?> defClass, String name, Object type) {
797 int kindFlags;
798 if (MethodHandleNatives.refKindIsField(refKind)) {
799 kindFlags = IS_FIELD;
800 if (!(type instanceof Class))
801 throw newIllegalArgumentException("not a field type");
802 } else if (MethodHandleNatives.refKindIsMethod(refKind)) {
803 kindFlags = IS_METHOD;
804 if (!(type instanceof MethodType))
805 throw newIllegalArgumentException("not a method type");
806 } else if (refKind == REF_newInvokeSpecial) {
807 kindFlags = IS_CONSTRUCTOR;
808 if (!(type instanceof MethodType) ||
809 !CONSTRUCTOR_NAME.equals(name))
810 throw newIllegalArgumentException("not a constructor type or name");
811 } else {
812 throw newIllegalArgumentException("bad reference kind "+refKind);
813 }
814 init(defClass, name, type, flagsMods(kindFlags, 0, refKind));
815 initResolved(false);
816 }
817 /** Query whether this member name is resolved to a non-static, non-final method.
818 */
819 public boolean hasReceiverTypeDispatch() {
820 return MethodHandleNatives.refKindDoesDispatch(getReferenceKind());
821 }
822
823 /** Query whether this member name is resolved.
824 * A resolved member name is one for which the JVM has found
825 * a method, constructor, field, or type binding corresponding exactly to the name.
826 * (Document?)
827 */
828 public boolean isResolved() {
829 return resolution == null;
830 }
831
832 private void initResolved(boolean isResolved) {
833 assert(this.resolution == null); // not initialized yet!
834 if (!isResolved)
835 this.resolution = this;
836 assert(isResolved() == isResolved);
837 }
838
839 void checkForTypeAlias(Class<?> refc) {
840 if (isInvocable()) {
841 MethodType type;
842 if (this.type instanceof MethodType)
843 type = (MethodType) this.type;
844 else
845 this.type = type = getMethodType();
846 if (type.erase() == type) return;
847 if (VerifyAccess.isTypeVisible(type, refc)) return;
848 throw new LinkageError("bad method type alias: "+type+" not visible from "+refc);
849 } else {
850 Class<?> type;
851 if (this.type instanceof Class<?>)
852 type = (Class<?>) this.type;
853 else
854 this.type = type = getFieldType();
855 if (VerifyAccess.isTypeVisible(type, refc)) return;
856 throw new LinkageError("bad field type alias: "+type+" not visible from "+refc);
857 }
858 }
859
860
861 /** Produce a string form of this member name.
862 * For types, it is simply the type's own string (as reported by {@code toString}).
863 * For fields, it is {@code "DeclaringClass.name/type"}.
864 * For methods and constructors, it is {@code "DeclaringClass.name(ptype...)rtype"}.
865 * If the declaring class is null, the prefix {@code "DeclaringClass."} is omitted.
866 * If the member is unresolved, a prefix {@code "*."} is prepended.
867 */
868 @SuppressWarnings("LocalVariableHidesMemberVariable")
869 @Override
870 public String toString() {
871 if (isType())
872 return type.toString(); // class java.lang.String
873 // else it is a field, method, or constructor
874 StringBuilder buf = new StringBuilder();
875 if (getDeclaringClass() != null) {
876 buf.append(getName(clazz));
877 buf.append('.');
878 }
879 String name = getName();
880 buf.append(name == null ? "*" : name);
881 Object type = getType();
882 if (!isInvocable()) {
883 buf.append('/');
884 buf.append(type == null ? "*" : getName(type));
885 } else {
886 buf.append(type == null ? "(*)*" : getName(type));
887 }
888 byte refKind = getReferenceKind();
889 if (refKind != REF_NONE) {
890 buf.append('/');
891 buf.append(MethodHandleNatives.refKindName(refKind));
892 }
893 //buf.append("#").append(System.identityHashCode(this));
894 return buf.toString();
895 }
896 private static String getName(Object obj) {
897 if (obj instanceof Class<?>)
898 return ((Class<?>)obj).getName();
899 return String.valueOf(obj);
900 }
901
902 public IllegalAccessException makeAccessException(String message, Object from) {
903 message = message + ": "+ toString();
904 if (from != null) {
905 if (from == MethodHandles.publicLookup()) {
906 message += ", from public Lookup";
907 } else {
908 Module m;
909 if (from instanceof MethodHandles.Lookup) {
910 MethodHandles.Lookup lookup = (MethodHandles.Lookup)from;
911 m = lookup.lookupClass().getModule();
912 } else {
913 m = from.getClass().getModule();
914 }
915 message += ", from " + from + " (" + m + ")";
916 }
917 }
918 return new IllegalAccessException(message);
919 }
920 private String message() {
921 if (isResolved())
922 return "no access";
923 else if (isConstructor())
924 return "no such constructor";
925 else if (isMethod())
926 return "no such method";
927 else
928 return "no such field";
929 }
930 public ReflectiveOperationException makeAccessException() {
931 String message = message() + ": "+ toString();
932 ReflectiveOperationException ex;
933 if (isResolved() || !(resolution instanceof NoSuchMethodError ||
934 resolution instanceof NoSuchFieldError))
935 ex = new IllegalAccessException(message);
936 else if (isConstructor())
937 ex = new NoSuchMethodException(message);
938 else if (isMethod())
939 ex = new NoSuchMethodException(message);
940 else
941 ex = new NoSuchFieldException(message);
942 if (resolution instanceof Throwable)
943 ex.initCause((Throwable) resolution);
944 return ex;
945 }
946
947 /** Actually making a query requires an access check. */
948 /*non-public*/ static Factory getFactory() {
949 return Factory.INSTANCE;
950 }
951 /** A factory type for resolving member names with the help of the VM.
952 * TBD: Define access-safe public constructors for this factory.
953 */
954 /*non-public*/ static class Factory {
955 private Factory() { } // singleton pattern
956 static Factory INSTANCE = new Factory();
957
958 private static int ALLOWED_FLAGS = ALL_KINDS;
959
960 /// Queries
961 List<MemberName> getMembers(Class<?> defc,
962 String matchName, Object matchType,
963 int matchFlags, Class<?> lookupClass) {
964 matchFlags &= ALLOWED_FLAGS;
965 String matchSig = null;
966 if (matchType != null) {
967 matchSig = BytecodeDescriptor.unparse(matchType);
968 if (matchSig.startsWith("("))
969 matchFlags &= ~(ALL_KINDS & ~IS_INVOCABLE);
970 else
971 matchFlags &= ~(ALL_KINDS & ~IS_FIELD);
972 }
973 final int BUF_MAX = 0x2000;
974 int len1 = matchName == null ? 10 : matchType == null ? 4 : 1;
975 MemberName[] buf = newMemberBuffer(len1);
976 int totalCount = 0;
977 ArrayList<MemberName[]> bufs = null;
978 int bufCount = 0;
979 for (;;) {
980 bufCount = MethodHandleNatives.getMembers(defc,
981 matchName, matchSig, matchFlags,
982 lookupClass,
983 totalCount, buf);
984 if (bufCount <= buf.length) {
985 if (bufCount < 0) bufCount = 0;
986 totalCount += bufCount;
987 break;
988 }
989 // JVM returned to us with an intentional overflow!
990 totalCount += buf.length;
991 int excess = bufCount - buf.length;
992 if (bufs == null) bufs = new ArrayList<>(1);
993 bufs.add(buf);
994 int len2 = buf.length;
995 len2 = Math.max(len2, excess);
996 len2 = Math.max(len2, totalCount / 4);
997 buf = newMemberBuffer(Math.min(BUF_MAX, len2));
998 }
999 ArrayList<MemberName> result = new ArrayList<>(totalCount);
1000 if (bufs != null) {
1001 for (MemberName[] buf0 : bufs) {
1002 Collections.addAll(result, buf0);
1003 }
1004 }
1005 result.addAll(Arrays.asList(buf).subList(0, bufCount));
1006 // Signature matching is not the same as type matching, since
1007 // one signature might correspond to several types.
1008 // So if matchType is a Class or MethodType, refilter the results.
1009 if (matchType != null && matchType != matchSig) {
1010 for (Iterator<MemberName> it = result.iterator(); it.hasNext();) {
1011 MemberName m = it.next();
1012 if (!matchType.equals(m.getType()))
1013 it.remove();
1014 }
1015 }
1016 return result;
1017 }
1018 /** Produce a resolved version of the given member.
1019 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1020 * Access checking is performed on behalf of the given {@code lookupClass}.
1021 * If lookup fails or access is not permitted, null is returned.
1022 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in.
1023 */
1024 private MemberName resolve(byte refKind, MemberName ref, Class<?> lookupClass) {
1025 MemberName m = ref.clone(); // JVM will side-effect the ref
1026 assert(refKind == m.getReferenceKind());
1027 try {
1028 // There are 4 entities in play here:
1029 // * LC: lookupClass
1030 // * REFC: symbolic reference class (MN.clazz before resolution);
1031 // * DEFC: resolved method holder (MN.clazz after resolution);
1032 // * PTYPES: parameter types (MN.type)
1033 //
1034 // What we care about when resolving a MemberName is consistency between DEFC and PTYPES.
1035 // We do type alias (TA) checks on DEFC to ensure that. DEFC is not known until the JVM
1036 // finishes the resolution, so do TA checks right after MHN.resolve() is over.
1037 //
1038 // All parameters passed by a caller are checked against MH type (PTYPES) on every invocation,
1039 // so it is safe to call a MH from any context.
1040 //
1041 // REFC view on PTYPES doesn't matter, since it is used only as a starting point for resolution and doesn't
1042 // participate in method selection.
1043 m = MethodHandleNatives.resolve(m, lookupClass);
1044 m.checkForTypeAlias(m.getDeclaringClass());
1045 m.resolution = null;
1046 } catch (ClassNotFoundException | LinkageError ex) {
1047 // JVM reports that the "bytecode behavior" would get an error
1048 assert(!m.isResolved());
1049 m.resolution = ex;
1050 return m;
1051 }
1052 assert(m.referenceKindIsConsistent());
1053 m.initResolved(true);
1054 assert(m.vminfoIsConsistent());
1055 return m;
1056 }
1057 /** Produce a resolved version of the given member.
1058 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1059 * Access checking is performed on behalf of the given {@code lookupClass}.
1060 * If lookup fails or access is not permitted, a {@linkplain ReflectiveOperationException} is thrown.
1061 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in.
1062 */
1063 public
1064 <NoSuchMemberException extends ReflectiveOperationException>
1065 MemberName resolveOrFail(byte refKind, MemberName m, Class<?> lookupClass,
1066 Class<NoSuchMemberException> nsmClass)
1067 throws IllegalAccessException, NoSuchMemberException {
1068 MemberName result = resolve(refKind, m, lookupClass);
1069 if (result.isResolved())
1070 return result;
1071 ReflectiveOperationException ex = result.makeAccessException();
1072 if (ex instanceof IllegalAccessException) throw (IllegalAccessException) ex;
1073 throw nsmClass.cast(ex);
1074 }
1075 /** Produce a resolved version of the given member.
1076 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1077 * Access checking is performed on behalf of the given {@code lookupClass}.
1078 * If lookup fails or access is not permitted, return null.
1079 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in.
1080 */
1081 public
1082 MemberName resolveOrNull(byte refKind, MemberName m, Class<?> lookupClass) {
1083 MemberName result = resolve(refKind, m, lookupClass);
1084 if (result.isResolved())
1085 return result;
1086 return null;
1087 }
1088 /** Return a list of all methods defined by the given class.
1089 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1090 * Access checking is performed on behalf of the given {@code lookupClass}.
1091 * Inaccessible members are not added to the last.
1092 */
1093 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers,
1094 Class<?> lookupClass) {
1095 return getMethods(defc, searchSupers, null, null, lookupClass);
1096 }
1097 /** Return a list of matching methods defined by the given class.
1098 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1099 * Returned methods will match the name (if not null) and the type (if not null).
1100 * Access checking is performed on behalf of the given {@code lookupClass}.
1101 * Inaccessible members are not added to the last.
1102 */
1103 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers,
1104 String name, MethodType type, Class<?> lookupClass) {
1105 int matchFlags = IS_METHOD | (searchSupers ? SEARCH_ALL_SUPERS : 0);
1106 return getMembers(defc, name, type, matchFlags, lookupClass);
1107 }
1108 /** Return a list of all constructors defined by the given class.
1109 * Access checking is performed on behalf of the given {@code lookupClass}.
1110 * Inaccessible members are not added to the last.
1111 */
1112 public List<MemberName> getConstructors(Class<?> defc, Class<?> lookupClass) {
1113 return getMembers(defc, null, null, IS_CONSTRUCTOR, lookupClass);
1114 }
1115 /** Return a list of all fields defined by the given class.
1116 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1117 * Access checking is performed on behalf of the given {@code lookupClass}.
1118 * Inaccessible members are not added to the last.
1119 */
1120 public List<MemberName> getFields(Class<?> defc, boolean searchSupers,
1121 Class<?> lookupClass) {
1122 return getFields(defc, searchSupers, null, null, lookupClass);
1123 }
1124 /** Return a list of all fields defined by the given class.
1125 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1126 * Returned fields will match the name (if not null) and the type (if not null).
1127 * Access checking is performed on behalf of the given {@code lookupClass}.
1128 * Inaccessible members are not added to the last.
1129 */
1130 public List<MemberName> getFields(Class<?> defc, boolean searchSupers,
1131 String name, Class<?> type, Class<?> lookupClass) {
1132 int matchFlags = IS_FIELD | (searchSupers ? SEARCH_ALL_SUPERS : 0);
1133 return getMembers(defc, name, type, matchFlags, lookupClass);
1134 }
1135 /** Return a list of all nested types defined by the given class.
1136 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1137 * Access checking is performed on behalf of the given {@code lookupClass}.
1138 * Inaccessible members are not added to the last.
1139 */
1140 public List<MemberName> getNestedTypes(Class<?> defc, boolean searchSupers,
1141 Class<?> lookupClass) {
1142 int matchFlags = IS_TYPE | (searchSupers ? SEARCH_ALL_SUPERS : 0);
1143 return getMembers(defc, null, null, matchFlags, lookupClass);
1144 }
1145 private static MemberName[] newMemberBuffer(int length) {
1146 MemberName[] buf = new MemberName[length];
1147 // fill the buffer with dummy structs for the JVM to fill in
1148 for (int i = 0; i < length; i++)
1149 buf[i] = new MemberName();
1150 return buf;
1151 }
1152 }
1153
1154 static {
1155 // StackFrameInfo stores Member and this provides the shared secrets
1156 // for stack walker to access MemberName information.
1157 SharedSecrets.setJavaLangInvokeAccess(new JavaLangInvokeAccess() {
1158 @Override
1159 public Object newMemberName() {
1160 return new MemberName();
1161 }
1162
1163 @Override
1164 public String getName(Object mname) {
1165 MemberName memberName = (MemberName)mname;
1166 return memberName.getName();
1167 }
1168
1169 @Override
1170 public boolean isNative(Object mname) {
1171 MemberName memberName = (MemberName)mname;
1172 return memberName.isNative();
1173 }
1174 });
1175 }
1176 }