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 private static final int MH_INVOKE_MODS = Modifier.NATIVE | Modifier.FINAL | Modifier.PUBLIC;
367
368 /** Utility method to query the modifier flags of this member. */
369 public boolean isStatic() {
370 return Modifier.isStatic(flags);
371 }
372 /** Utility method to query the modifier flags of this member. */
373 public boolean isPublic() {
374 return Modifier.isPublic(flags);
375 }
376 /** Utility method to query the modifier flags of this member. */
377 public boolean isPrivate() {
378 return Modifier.isPrivate(flags);
379 }
380 /** Utility method to query the modifier flags of this member. */
381 public boolean isProtected() {
382 return Modifier.isProtected(flags);
383 }
384 /** Utility method to query the modifier flags of this member. */
385 public boolean isFinal() {
386 return Modifier.isFinal(flags);
387 }
388 /** Utility method to query whether this member or its defining class is final. */
389 public boolean canBeStaticallyBound() {
390 return Modifier.isFinal(flags | clazz.getModifiers());
391 }
392 /** Utility method to query the modifier flags of this member. */
393 public boolean isVolatile() {
394 return Modifier.isVolatile(flags);
395 }
396 /** Utility method to query the modifier flags of this member. */
397 public boolean isAbstract() {
398 return Modifier.isAbstract(flags);
399 }
400 /** Utility method to query the modifier flags of this member. */
401 public boolean isNative() {
402 return Modifier.isNative(flags);
403 }
404 // let the rest (native, volatile, transient, etc.) be tested via Modifier.isFoo
405
406 // unofficial modifier flags, used by HotSpot:
407 static final int BRIDGE = 0x00000040;
408 static final int VARARGS = 0x00000080;
409 static final int SYNTHETIC = 0x00001000;
410 static final int ANNOTATION= 0x00002000;
411 static final int ENUM = 0x00004000;
412 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */
413 public boolean isBridge() {
414 return testAllFlags(IS_METHOD | BRIDGE);
415 }
416 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */
417 public boolean isVarargs() {
418 return testAllFlags(VARARGS) && isInvocable();
419 }
420 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */
421 public boolean isSynthetic() {
422 return testAllFlags(SYNTHETIC);
423 }
424
425 static final String CONSTRUCTOR_NAME = "<init>"; // the ever-popular
426
427 // modifiers exported by the JVM:
428 static final int RECOGNIZED_MODIFIERS = 0xFFFF;
429
430 // private flags, not part of RECOGNIZED_MODIFIERS:
431 static final int
432 IS_METHOD = MN_IS_METHOD, // method (not constructor)
433 IS_CONSTRUCTOR = MN_IS_CONSTRUCTOR, // constructor
434 IS_FIELD = MN_IS_FIELD, // field
435 IS_TYPE = MN_IS_TYPE, // nested type
436 CALLER_SENSITIVE = MN_CALLER_SENSITIVE; // @CallerSensitive annotation detected
437
438 static final int ALL_ACCESS = Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED;
439 static final int ALL_KINDS = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE;
440 static final int IS_INVOCABLE = IS_METHOD | IS_CONSTRUCTOR;
441 static final int IS_FIELD_OR_METHOD = IS_METHOD | IS_FIELD;
442 static final int SEARCH_ALL_SUPERS = MN_SEARCH_SUPERCLASSES | MN_SEARCH_INTERFACES;
443
444 /** Utility method to query whether this member is a method or constructor. */
445 public boolean isInvocable() {
446 return testAnyFlags(IS_INVOCABLE);
447 }
448 /** Utility method to query whether this member is a method, constructor, or field. */
449 public boolean isFieldOrMethod() {
450 return testAnyFlags(IS_FIELD_OR_METHOD);
451 }
452 /** Query whether this member is a method. */
453 public boolean isMethod() {
454 return testAllFlags(IS_METHOD);
455 }
456 /** Query whether this member is a constructor. */
457 public boolean isConstructor() {
458 return testAllFlags(IS_CONSTRUCTOR);
459 }
460 /** Query whether this member is a field. */
461 public boolean isField() {
462 return testAllFlags(IS_FIELD);
463 }
464 /** Query whether this member is a type. */
465 public boolean isType() {
466 return testAllFlags(IS_TYPE);
467 }
468 /** Utility method to query whether this member is neither public, private, nor protected. */
469 public boolean isPackage() {
470 return !testAnyFlags(ALL_ACCESS);
471 }
472 /** Query whether this member has a CallerSensitive annotation. */
473 public boolean isCallerSensitive() {
474 return testAllFlags(CALLER_SENSITIVE);
475 }
476
477 /** Utility method to query whether this member is accessible from a given lookup class. */
478 public boolean isAccessibleFrom(Class<?> lookupClass) {
479 int mode = (ALL_ACCESS|MethodHandles.Lookup.PACKAGE|MethodHandles.Lookup.MODULE);
480 return VerifyAccess.isMemberAccessible(this.getDeclaringClass(), this.getDeclaringClass(), flags,
481 lookupClass, mode);
482 }
483
484 /** Initialize a query. It is not resolved. */
485 private void init(Class<?> defClass, String name, Object type, int flags) {
486 // defining class is allowed to be null (for a naked name/type pair)
487 //name.toString(); // null check
488 //type.equals(type); // null check
489 // fill in fields:
490 this.clazz = defClass;
491 this.name = name;
492 this.type = type;
493 this.flags = flags;
494 assert(testAnyFlags(ALL_KINDS));
495 assert(this.resolution == null); // nobody should have touched this yet
496 //assert(referenceKindIsConsistent()); // do this after resolution
497 }
498
499 /**
500 * Calls down to the VM to fill in the fields. This method is
501 * synchronized to avoid racing calls.
502 */
503 private void expandFromVM() {
504 if (type != null) {
505 return;
506 }
507 if (!isResolved()) {
508 return;
509 }
510 MethodHandleNatives.expand(this);
511 }
512
513 // Capturing information from the Core Reflection API:
514 private static int flagsMods(int flags, int mods, byte refKind) {
515 assert((flags & RECOGNIZED_MODIFIERS) == 0);
516 assert((mods & ~RECOGNIZED_MODIFIERS) == 0);
517 assert((refKind & ~MN_REFERENCE_KIND_MASK) == 0);
518 return flags | mods | (refKind << MN_REFERENCE_KIND_SHIFT);
519 }
520 /** Create a name for the given reflected method. The resulting name will be in a resolved state. */
521 public MemberName(Method m) {
522 this(m, false);
523 }
524 @SuppressWarnings("LeakingThisInConstructor")
525 public MemberName(Method m, boolean wantSpecial) {
526 Objects.requireNonNull(m);
527 // fill in vmtarget, vmindex while we have m in hand:
528 MethodHandleNatives.init(this, m);
529 if (clazz == null) { // MHN.init failed
530 if (m.getDeclaringClass() == MethodHandle.class &&
531 isMethodHandleInvokeName(m.getName())) {
532 // The JVM did not reify this signature-polymorphic instance.
533 // Need a special case here.
534 // See comments on MethodHandleNatives.linkMethod.
535 MethodType type = MethodType.methodType(m.getReturnType(), m.getParameterTypes());
536 int flags = flagsMods(IS_METHOD, m.getModifiers(), REF_invokeVirtual);
537 init(MethodHandle.class, m.getName(), type, flags);
538 if (isMethodHandleInvoke())
539 return;
540 }
541 throw new LinkageError(m.toString());
542 }
543 assert(isResolved() && this.clazz != null);
544 this.name = m.getName();
545 if (this.type == null)
546 this.type = new Object[] { m.getReturnType(), m.getParameterTypes() };
547 if (wantSpecial) {
548 if (isAbstract())
549 throw new AbstractMethodError(this.toString());
550 if (getReferenceKind() == REF_invokeVirtual)
551 changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual);
552 else if (getReferenceKind() == REF_invokeInterface)
553 // invokeSpecial on a default method
554 changeReferenceKind(REF_invokeSpecial, REF_invokeInterface);
555 }
556 }
557 public MemberName asSpecial() {
558 switch (getReferenceKind()) {
559 case REF_invokeSpecial: return this;
560 case REF_invokeVirtual: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual);
561 case REF_invokeInterface: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeInterface);
562 case REF_newInvokeSpecial: return clone().changeReferenceKind(REF_invokeSpecial, REF_newInvokeSpecial);
563 }
564 throw new IllegalArgumentException(this.toString());
565 }
566 /** If this MN is not REF_newInvokeSpecial, return a clone with that ref. kind.
567 * In that case it must already be REF_invokeSpecial.
568 */
569 public MemberName asConstructor() {
570 switch (getReferenceKind()) {
571 case REF_invokeSpecial: return clone().changeReferenceKind(REF_newInvokeSpecial, REF_invokeSpecial);
572 case REF_newInvokeSpecial: return this;
573 }
574 throw new IllegalArgumentException(this.toString());
575 }
576 /** If this MN is a REF_invokeSpecial, return a clone with the "normal" kind
577 * REF_invokeVirtual; also switch either to REF_invokeInterface if clazz.isInterface.
578 * The end result is to get a fully virtualized version of the MN.
579 * (Note that resolving in the JVM will sometimes devirtualize, changing
580 * REF_invokeVirtual of a final to REF_invokeSpecial, and REF_invokeInterface
581 * in some corner cases to either of the previous two; this transform
582 * undoes that change under the assumption that it occurred.)
583 */
584 public MemberName asNormalOriginal() {
585 byte normalVirtual = clazz.isInterface() ? REF_invokeInterface : REF_invokeVirtual;
586 byte refKind = getReferenceKind();
587 byte newRefKind = refKind;
588 MemberName result = this;
589 switch (refKind) {
590 case REF_invokeInterface:
591 case REF_invokeVirtual:
592 case REF_invokeSpecial:
593 newRefKind = normalVirtual;
594 break;
595 }
596 if (newRefKind == refKind)
597 return this;
598 result = clone().changeReferenceKind(newRefKind, refKind);
599 assert(this.referenceKindIsConsistentWith(result.getReferenceKind()));
600 return result;
601 }
602 /** Create a name for the given reflected constructor. The resulting name will be in a resolved state. */
603 @SuppressWarnings("LeakingThisInConstructor")
604 public MemberName(Constructor<?> ctor) {
605 Objects.requireNonNull(ctor);
606 // fill in vmtarget, vmindex while we have ctor in hand:
607 MethodHandleNatives.init(this, ctor);
608 assert(isResolved() && this.clazz != null);
609 this.name = CONSTRUCTOR_NAME;
610 if (this.type == null)
611 this.type = new Object[] { void.class, ctor.getParameterTypes() };
612 }
613 /** Create a name for the given reflected field. The resulting name will be in a resolved state.
614 */
615 public MemberName(Field fld) {
616 this(fld, false);
617 }
618 @SuppressWarnings("LeakingThisInConstructor")
619 public MemberName(Field fld, boolean makeSetter) {
620 Objects.requireNonNull(fld);
621 // fill in vmtarget, vmindex while we have fld in hand:
622 MethodHandleNatives.init(this, fld);
623 assert(isResolved() && this.clazz != null);
624 this.name = fld.getName();
625 this.type = fld.getType();
626 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField));
627 byte refKind = this.getReferenceKind();
628 assert(refKind == (isStatic() ? REF_getStatic : REF_getField));
629 if (makeSetter) {
630 changeReferenceKind((byte)(refKind + (REF_putStatic - REF_getStatic)), refKind);
631 }
632 }
633 public boolean isGetter() {
634 return MethodHandleNatives.refKindIsGetter(getReferenceKind());
635 }
636 public boolean isSetter() {
637 return MethodHandleNatives.refKindIsSetter(getReferenceKind());
638 }
639 public MemberName asSetter() {
640 byte refKind = getReferenceKind();
641 assert(MethodHandleNatives.refKindIsGetter(refKind));
642 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField));
643 byte setterRefKind = (byte)(refKind + (REF_putField - REF_getField));
644 return clone().changeReferenceKind(setterRefKind, refKind);
645 }
646 /** Create a name for the given class. The resulting name will be in a resolved state. */
647 public MemberName(Class<?> type) {
648 init(type.getDeclaringClass(), type.getSimpleName(), type,
649 flagsMods(IS_TYPE, type.getModifiers(), REF_NONE));
650 initResolved(true);
651 }
652
653 /**
654 * Create a name for a signature-polymorphic invoker.
655 * This is a placeholder for a signature-polymorphic instance
656 * (of MH.invokeExact, etc.) that the JVM does not reify.
657 * See comments on {@link MethodHandleNatives#linkMethod}.
658 */
659 static MemberName makeMethodHandleInvoke(String name, MethodType type) {
660 return makeMethodHandleInvoke(name, type, MH_INVOKE_MODS | SYNTHETIC);
661 }
662 static MemberName makeMethodHandleInvoke(String name, MethodType type, int mods) {
663 MemberName mem = new MemberName(MethodHandle.class, name, type, REF_invokeVirtual);
664 mem.flags |= mods; // it's not resolved, but add these modifiers anyway
665 assert(mem.isMethodHandleInvoke()) : mem;
666 return mem;
667 }
668
669 // bare-bones constructor; the JVM will fill it in
670 MemberName() { }
671
672 // locally useful cloner
673 @Override protected MemberName clone() {
674 try {
675 return (MemberName) super.clone();
676 } catch (CloneNotSupportedException ex) {
677 throw newInternalError(ex);
678 }
679 }
680
681 /** Get the definition of this member name.
682 * This may be in a super-class of the declaring class of this member.
683 */
684 public MemberName getDefinition() {
685 if (!isResolved()) throw new IllegalStateException("must be resolved: "+this);
686 if (isType()) return this;
687 MemberName res = this.clone();
688 res.clazz = null;
689 res.type = null;
690 res.name = null;
691 res.resolution = res;
692 res.expandFromVM();
693 assert(res.getName().equals(this.getName()));
694 return res;
695 }
696
697 @Override
698 public int hashCode() {
699 // Avoid autoboxing getReferenceKind(), since this is used early and will force
700 // early initialization of Byte$ByteCache
701 return Objects.hash(clazz, new Byte(getReferenceKind()), name, getType());
702 }
703
704 @Override
705 public boolean equals(Object that) {
706 return (that instanceof MemberName && this.equals((MemberName)that));
707 }
708
709 /** Decide if two member names have exactly the same symbolic content.
710 * Does not take into account any actual class members, so even if
711 * two member names resolve to the same actual member, they may
712 * be distinct references.
713 */
714 public boolean equals(MemberName that) {
715 if (this == that) return true;
716 if (that == null) return false;
717 return this.clazz == that.clazz
718 && this.getReferenceKind() == that.getReferenceKind()
719 && Objects.equals(this.name, that.name)
720 && Objects.equals(this.getType(), that.getType());
721 }
722
723 // Construction from symbolic parts, for queries:
724 /** Create a field or type name from the given components:
725 * Declaring class, name, type, reference kind.
726 * The declaring class may be supplied as null if this is to be a bare name and type.
727 * The resulting name will in an unresolved state.
728 */
729 public MemberName(Class<?> defClass, String name, Class<?> type, byte refKind) {
730 init(defClass, name, type, flagsMods(IS_FIELD, 0, refKind));
731 initResolved(false);
732 }
733 /** Create a method or constructor name from the given components:
734 * Declaring class, name, type, reference kind.
735 * It will be a constructor if and only if the name is {@code "<init>"}.
736 * The declaring class may be supplied as null if this is to be a bare name and type.
737 * The last argument is optional, a boolean which requests REF_invokeSpecial.
738 * The resulting name will in an unresolved state.
739 */
740 public MemberName(Class<?> defClass, String name, MethodType type, byte refKind) {
741 int initFlags = (name != null && name.equals(CONSTRUCTOR_NAME) ? IS_CONSTRUCTOR : IS_METHOD);
742 init(defClass, name, type, flagsMods(initFlags, 0, refKind));
743 initResolved(false);
744 }
745 /** Create a method, constructor, or field name from the given components:
746 * Reference kind, declaring class, name, type.
747 */
748 public MemberName(byte refKind, Class<?> defClass, String name, Object type) {
749 int kindFlags;
750 if (MethodHandleNatives.refKindIsField(refKind)) {
751 kindFlags = IS_FIELD;
752 if (!(type instanceof Class))
753 throw newIllegalArgumentException("not a field type");
754 } else if (MethodHandleNatives.refKindIsMethod(refKind)) {
755 kindFlags = IS_METHOD;
756 if (!(type instanceof MethodType))
757 throw newIllegalArgumentException("not a method type");
758 } else if (refKind == REF_newInvokeSpecial) {
759 kindFlags = IS_CONSTRUCTOR;
760 if (!(type instanceof MethodType) ||
761 !CONSTRUCTOR_NAME.equals(name))
762 throw newIllegalArgumentException("not a constructor type or name");
763 } else {
764 throw newIllegalArgumentException("bad reference kind "+refKind);
765 }
766 init(defClass, name, type, flagsMods(kindFlags, 0, refKind));
767 initResolved(false);
768 }
769 /** Query whether this member name is resolved to a non-static, non-final method.
770 */
771 public boolean hasReceiverTypeDispatch() {
772 return MethodHandleNatives.refKindDoesDispatch(getReferenceKind());
773 }
774
775 /** Query whether this member name is resolved.
776 * A resolved member name is one for which the JVM has found
777 * a method, constructor, field, or type binding corresponding exactly to the name.
778 * (Document?)
779 */
780 public boolean isResolved() {
781 return resolution == null;
782 }
783
784 private void initResolved(boolean isResolved) {
785 assert(this.resolution == null); // not initialized yet!
786 if (!isResolved)
787 this.resolution = this;
788 assert(isResolved() == isResolved);
789 }
790
791 void checkForTypeAlias() {
792 if (isInvocable()) {
793 MethodType type;
794 if (this.type instanceof MethodType)
795 type = (MethodType) this.type;
796 else
797 this.type = type = getMethodType();
798 if (type.erase() == type) return;
799 if (VerifyAccess.isTypeVisible(type, clazz)) return;
800 throw new LinkageError("bad method type alias: "+type+" not visible from "+clazz);
801 } else {
802 Class<?> type;
803 if (this.type instanceof Class<?>)
804 type = (Class<?>) this.type;
805 else
806 this.type = type = getFieldType();
807 if (VerifyAccess.isTypeVisible(type, clazz)) return;
808 throw new LinkageError("bad field type alias: "+type+" not visible from "+clazz);
809 }
810 }
811
812
813 /** Produce a string form of this member name.
814 * For types, it is simply the type's own string (as reported by {@code toString}).
815 * For fields, it is {@code "DeclaringClass.name/type"}.
816 * For methods and constructors, it is {@code "DeclaringClass.name(ptype...)rtype"}.
817 * If the declaring class is null, the prefix {@code "DeclaringClass."} is omitted.
818 * If the member is unresolved, a prefix {@code "*."} is prepended.
819 */
820 @SuppressWarnings("LocalVariableHidesMemberVariable")
821 @Override
822 public String toString() {
823 if (isType())
824 return type.toString(); // class java.lang.String
825 // else it is a field, method, or constructor
826 StringBuilder buf = new StringBuilder();
827 if (getDeclaringClass() != null) {
828 buf.append(getName(clazz));
829 buf.append('.');
830 }
831 String name = getName();
832 buf.append(name == null ? "*" : name);
833 Object type = getType();
834 if (!isInvocable()) {
835 buf.append('/');
836 buf.append(type == null ? "*" : getName(type));
837 } else {
838 buf.append(type == null ? "(*)*" : getName(type));
839 }
840 byte refKind = getReferenceKind();
841 if (refKind != REF_NONE) {
842 buf.append('/');
843 buf.append(MethodHandleNatives.refKindName(refKind));
844 }
845 //buf.append("#").append(System.identityHashCode(this));
846 return buf.toString();
847 }
848 private static String getName(Object obj) {
849 if (obj instanceof Class<?>)
850 return ((Class<?>)obj).getName();
851 return String.valueOf(obj);
852 }
853
854 public IllegalAccessException makeAccessException(String message, Object from) {
855 message = message + ": "+ toString();
856 if (from != null) {
857 if (from == MethodHandles.publicLookup()) {
858 message += ", from public Lookup";
859 } else {
860 Module m;
861 if (from instanceof MethodHandles.Lookup) {
862 MethodHandles.Lookup lookup = (MethodHandles.Lookup)from;
863 m = lookup.lookupClass().getModule();
864 } else {
865 m = from.getClass().getModule();
866 }
867 message += ", from " + from + " (" + m + ")";
868 }
869 }
870 return new IllegalAccessException(message);
871 }
872 private String message() {
873 if (isResolved())
874 return "no access";
875 else if (isConstructor())
876 return "no such constructor";
877 else if (isMethod())
878 return "no such method";
879 else
880 return "no such field";
881 }
882 public ReflectiveOperationException makeAccessException() {
883 String message = message() + ": "+ toString();
884 ReflectiveOperationException ex;
885 if (isResolved() || !(resolution instanceof NoSuchMethodError ||
886 resolution instanceof NoSuchFieldError))
887 ex = new IllegalAccessException(message);
888 else if (isConstructor())
889 ex = new NoSuchMethodException(message);
890 else if (isMethod())
891 ex = new NoSuchMethodException(message);
892 else
893 ex = new NoSuchFieldException(message);
894 if (resolution instanceof Throwable)
895 ex.initCause((Throwable) resolution);
896 return ex;
897 }
898
899 /** Actually making a query requires an access check. */
900 /*non-public*/ static Factory getFactory() {
901 return Factory.INSTANCE;
902 }
903 /** A factory type for resolving member names with the help of the VM.
904 * TBD: Define access-safe public constructors for this factory.
905 */
906 /*non-public*/ static class Factory {
907 private Factory() { } // singleton pattern
908 static Factory INSTANCE = new Factory();
909
910 private static int ALLOWED_FLAGS = ALL_KINDS;
911
912 /// Queries
913 List<MemberName> getMembers(Class<?> defc,
914 String matchName, Object matchType,
915 int matchFlags, Class<?> lookupClass) {
916 matchFlags &= ALLOWED_FLAGS;
917 String matchSig = null;
918 if (matchType != null) {
919 matchSig = BytecodeDescriptor.unparse(matchType);
920 if (matchSig.startsWith("("))
921 matchFlags &= ~(ALL_KINDS & ~IS_INVOCABLE);
922 else
923 matchFlags &= ~(ALL_KINDS & ~IS_FIELD);
924 }
925 final int BUF_MAX = 0x2000;
926 int len1 = matchName == null ? 10 : matchType == null ? 4 : 1;
927 MemberName[] buf = newMemberBuffer(len1);
928 int totalCount = 0;
929 ArrayList<MemberName[]> bufs = null;
930 int bufCount = 0;
931 for (;;) {
932 bufCount = MethodHandleNatives.getMembers(defc,
933 matchName, matchSig, matchFlags,
934 lookupClass,
935 totalCount, buf);
936 if (bufCount <= buf.length) {
937 if (bufCount < 0) bufCount = 0;
938 totalCount += bufCount;
939 break;
940 }
941 // JVM returned to us with an intentional overflow!
942 totalCount += buf.length;
943 int excess = bufCount - buf.length;
944 if (bufs == null) bufs = new ArrayList<>(1);
945 bufs.add(buf);
946 int len2 = buf.length;
947 len2 = Math.max(len2, excess);
948 len2 = Math.max(len2, totalCount / 4);
949 buf = newMemberBuffer(Math.min(BUF_MAX, len2));
950 }
951 ArrayList<MemberName> result = new ArrayList<>(totalCount);
952 if (bufs != null) {
953 for (MemberName[] buf0 : bufs) {
954 Collections.addAll(result, buf0);
955 }
956 }
957 result.addAll(Arrays.asList(buf).subList(0, bufCount));
958 // Signature matching is not the same as type matching, since
959 // one signature might correspond to several types.
960 // So if matchType is a Class or MethodType, refilter the results.
961 if (matchType != null && matchType != matchSig) {
962 for (Iterator<MemberName> it = result.iterator(); it.hasNext();) {
963 MemberName m = it.next();
964 if (!matchType.equals(m.getType()))
965 it.remove();
966 }
967 }
968 return result;
969 }
970 /** Produce a resolved version of the given member.
971 * Super types are searched (for inherited members) if {@code searchSupers} is true.
972 * Access checking is performed on behalf of the given {@code lookupClass}.
973 * If lookup fails or access is not permitted, null is returned.
974 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in.
975 */
976 private MemberName resolve(byte refKind, MemberName ref, Class<?> lookupClass) {
977 MemberName m = ref.clone(); // JVM will side-effect the ref
978 assert(refKind == m.getReferenceKind());
979 try {
980 m = MethodHandleNatives.resolve(m, lookupClass);
981 m.checkForTypeAlias();
982 m.resolution = null;
983 } catch (LinkageError ex) {
984 // JVM reports that the "bytecode behavior" would get an error
985 assert(!m.isResolved());
986 m.resolution = ex;
987 return m;
988 }
989 assert(m.referenceKindIsConsistent());
990 m.initResolved(true);
991 assert(m.vminfoIsConsistent());
992 return m;
993 }
994 /** Produce a resolved version of the given member.
995 * Super types are searched (for inherited members) if {@code searchSupers} is true.
996 * Access checking is performed on behalf of the given {@code lookupClass}.
997 * If lookup fails or access is not permitted, a {@linkplain ReflectiveOperationException} is thrown.
998 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in.
999 */
1000 public
1001 <NoSuchMemberException extends ReflectiveOperationException>
1002 MemberName resolveOrFail(byte refKind, MemberName m, Class<?> lookupClass,
1003 Class<NoSuchMemberException> nsmClass)
1004 throws IllegalAccessException, NoSuchMemberException {
1005 MemberName result = resolve(refKind, m, lookupClass);
1006 if (result.isResolved())
1007 return result;
1008 ReflectiveOperationException ex = result.makeAccessException();
1009 if (ex instanceof IllegalAccessException) throw (IllegalAccessException) ex;
1010 throw nsmClass.cast(ex);
1011 }
1012 /** Produce a resolved version of the given member.
1013 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1014 * Access checking is performed on behalf of the given {@code lookupClass}.
1015 * If lookup fails or access is not permitted, return null.
1016 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in.
1017 */
1018 public
1019 MemberName resolveOrNull(byte refKind, MemberName m, Class<?> lookupClass) {
1020 MemberName result = resolve(refKind, m, lookupClass);
1021 if (result.isResolved())
1022 return result;
1023 return null;
1024 }
1025 /** Return a list of all methods defined by the given class.
1026 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1027 * Access checking is performed on behalf of the given {@code lookupClass}.
1028 * Inaccessible members are not added to the last.
1029 */
1030 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers,
1031 Class<?> lookupClass) {
1032 return getMethods(defc, searchSupers, null, null, lookupClass);
1033 }
1034 /** Return a list of matching methods defined by the given class.
1035 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1036 * Returned methods will match the name (if not null) and the type (if not null).
1037 * Access checking is performed on behalf of the given {@code lookupClass}.
1038 * Inaccessible members are not added to the last.
1039 */
1040 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers,
1041 String name, MethodType type, Class<?> lookupClass) {
1042 int matchFlags = IS_METHOD | (searchSupers ? SEARCH_ALL_SUPERS : 0);
1043 return getMembers(defc, name, type, matchFlags, lookupClass);
1044 }
1045 /** Return a list of all constructors defined by the given class.
1046 * Access checking is performed on behalf of the given {@code lookupClass}.
1047 * Inaccessible members are not added to the last.
1048 */
1049 public List<MemberName> getConstructors(Class<?> defc, Class<?> lookupClass) {
1050 return getMembers(defc, null, null, IS_CONSTRUCTOR, lookupClass);
1051 }
1052 /** Return a list of all fields defined by the given class.
1053 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1054 * Access checking is performed on behalf of the given {@code lookupClass}.
1055 * Inaccessible members are not added to the last.
1056 */
1057 public List<MemberName> getFields(Class<?> defc, boolean searchSupers,
1058 Class<?> lookupClass) {
1059 return getFields(defc, searchSupers, null, null, lookupClass);
1060 }
1061 /** Return a list of all fields defined by the given class.
1062 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1063 * Returned fields will match the name (if not null) and the type (if not null).
1064 * Access checking is performed on behalf of the given {@code lookupClass}.
1065 * Inaccessible members are not added to the last.
1066 */
1067 public List<MemberName> getFields(Class<?> defc, boolean searchSupers,
1068 String name, Class<?> type, Class<?> lookupClass) {
1069 int matchFlags = IS_FIELD | (searchSupers ? SEARCH_ALL_SUPERS : 0);
1070 return getMembers(defc, name, type, matchFlags, lookupClass);
1071 }
1072 /** Return a list of all nested types defined by the given class.
1073 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1074 * Access checking is performed on behalf of the given {@code lookupClass}.
1075 * Inaccessible members are not added to the last.
1076 */
1077 public List<MemberName> getNestedTypes(Class<?> defc, boolean searchSupers,
1078 Class<?> lookupClass) {
1079 int matchFlags = IS_TYPE | (searchSupers ? SEARCH_ALL_SUPERS : 0);
1080 return getMembers(defc, null, null, matchFlags, lookupClass);
1081 }
1082 private static MemberName[] newMemberBuffer(int length) {
1083 MemberName[] buf = new MemberName[length];
1084 // fill the buffer with dummy structs for the JVM to fill in
1085 for (int i = 0; i < length; i++)
1086 buf[i] = new MemberName();
1087 return buf;
1088 }
1089 }
1090
1091 static {
1092 // Allow privileged classes outside of java.lang
1093 jdk.internal.misc.SharedSecrets.setJavaLangInvokeAccess(new jdk.internal.misc.JavaLangInvokeAccess() {
1094 public Object newMemberName() {
1095 return new MemberName();
1096 }
1097 public String getName(Object mname) {
1098 MemberName memberName = (MemberName)mname;
1099 return memberName.getName();
1100 }
1101 });
1102 }
1103 }