1 /* 2 * Copyright (c) 2008, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package java.lang.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.util.ArrayList; 37 import java.util.Arrays; 38 import java.util.Collections; 39 import java.util.Iterator; 40 import java.util.List; 41 import static java.lang.invoke.MethodHandleNatives.Constants.*; 42 import static java.lang.invoke.MethodHandleStatics.*; 43 import java.util.Objects; 44 45 /** 46 * A {@code MemberName} is a compact symbolic datum which fully characterizes 47 * a method or field reference. 48 * A member name refers to a field, method, constructor, or member type. 49 * Every member name has a simple name (a string) and a type (either a Class or MethodType). 50 * A member name may also have a non-null declaring class, or it may be simply 51 * a naked name/type pair. 52 * A member name may also have non-zero modifier flags. 53 * Finally, a member name may be either resolved or unresolved. 54 * If it is resolved, the existence of the named 55 * <p> 56 * Whether resolved or not, a member name provides no access rights or 57 * invocation capability to its possessor. It is merely a compact 58 * representation of all symbolic information necessary to link to 59 * and properly use the named member. 60 * <p> 61 * When resolved, a member name's internal implementation may include references to JVM metadata. 62 * This representation is stateless and only descriptive. 63 * It provides no private information and no capability to use the member. 64 * <p> 65 * By contrast, a {@linkplain java.lang.reflect.Method} contains fuller information 66 * about the internals of a method (except its bytecodes) and also 67 * allows invocation. A MemberName is much lighter than a Method, 68 * since it contains about 7 fields to the 16 of Method (plus its sub-arrays), 69 * and those seven fields omit much of the information in Method. 70 * @author jrose 71 */ 72 /*non-public*/ final class MemberName implements Member, Cloneable { 73 private Class<?> clazz; // class in which the method is defined 74 private String name; // may be null if not yet materialized 75 private Object type; // may be null if not yet materialized 76 private int flags; // modifier bits; see reflect.Modifier 77 //@Injected JVM_Method* vmtarget; 78 //@Injected int vmindex; 79 private Object resolution; // if null, this guy is resolved 80 81 /** Return the declaring class of this member. 82 * In the case of a bare name and type, the declaring class will be null. 83 */ 84 public Class<?> getDeclaringClass() { 85 return clazz; 86 } 87 88 /** Utility method producing the class loader of the declaring class. */ 89 public ClassLoader getClassLoader() { 90 return clazz.getClassLoader(); 91 } 92 93 /** Return the simple name of this member. 94 * For a type, it is the same as {@link Class#getSimpleName}. 95 * For a method or field, it is the simple name of the member. 96 * For a constructor, it is always {@code "<init>"}. 97 */ 98 public String getName() { 99 if (name == null) { 100 expandFromVM(); 101 if (name == null) { 102 return null; 103 } 104 } 105 return name; 106 } 107 108 public MethodType getMethodOrFieldType() { 109 if (isInvocable()) 110 return getMethodType(); 111 if (isGetter()) 112 return MethodType.methodType(getFieldType()); 113 if (isSetter()) 114 return MethodType.methodType(void.class, getFieldType()); 115 throw new InternalError("not a method or field: "+this); 116 } 117 118 /** Return the declared type of this member, which 119 * must be a method or constructor. 120 */ 121 public MethodType getMethodType() { 122 if (type == null) { 123 expandFromVM(); 124 if (type == null) { 125 return null; 126 } 127 } 128 if (!isInvocable()) { 129 throw newIllegalArgumentException("not invocable, no method type"); 130 } 131 132 { 133 // Get a snapshot of type which doesn't get changed by racing threads. 134 final Object type = this.type; 135 if (type instanceof MethodType) { 136 return (MethodType) type; 137 } 138 } 139 140 // type is not a MethodType yet. Convert it thread-safely. 141 synchronized (this) { 142 if (type instanceof String) { 143 String sig = (String) type; 144 MethodType res = MethodType.fromMethodDescriptorString(sig, getClassLoader()); 145 type = res; 146 } else if (type instanceof Object[]) { 147 Object[] typeInfo = (Object[]) type; 148 Class<?>[] ptypes = (Class<?>[]) typeInfo[1]; 149 Class<?> rtype = (Class<?>) typeInfo[0]; 150 MethodType res = MethodType.methodType(rtype, ptypes); 151 type = res; 152 } 153 // Make sure type is a MethodType for racing threads. 154 assert type instanceof MethodType : "bad method type " + type; 155 } 156 return (MethodType) type; 157 } 158 159 /** Return the actual type under which this method or constructor must be invoked. 160 * For non-static methods or constructors, this is the type with a leading parameter, 161 * a reference to declaring class. For static methods, it is the same as the declared type. 162 */ 163 public MethodType getInvocationType() { 164 MethodType itype = getMethodOrFieldType(); 165 if (isConstructor() && getReferenceKind() == REF_newInvokeSpecial) 166 return itype.changeReturnType(clazz); 167 if (!isStatic()) 168 return itype.insertParameterTypes(0, clazz); 169 return itype; 170 } 171 172 /** Utility method producing the parameter types of the method type. */ 173 public Class<?>[] getParameterTypes() { 174 return getMethodType().parameterArray(); 175 } 176 177 /** Utility method producing the return type of the method type. */ 178 public Class<?> getReturnType() { 179 return getMethodType().returnType(); 180 } 181 182 /** Return the declared type of this member, which 183 * must be a field or type. 184 * If it is a type member, that type itself is returned. 185 */ 186 public Class<?> getFieldType() { 187 if (type == null) { 188 expandFromVM(); 189 if (type == null) { 190 return null; 191 } 192 } 193 if (isInvocable()) { 194 throw newIllegalArgumentException("not a field or nested class, no simple type"); 195 } 196 197 { 198 // Get a snapshot of type which doesn't get changed by racing threads. 199 final Object type = this.type; 200 if (type instanceof Class<?>) { 201 return (Class<?>) type; 202 } 203 } 204 205 // type is not a Class yet. Convert it thread-safely. 206 synchronized (this) { 207 if (type instanceof String) { 208 String sig = (String) type; 209 MethodType mtype = MethodType.fromMethodDescriptorString("()"+sig, getClassLoader()); 210 Class<?> res = mtype.returnType(); 211 type = res; 212 } 213 // Make sure type is a Class for racing threads. 214 assert type instanceof Class<?> : "bad field type " + type; 215 } 216 return (Class<?>) type; 217 } 218 219 /** Utility method to produce either the method type or field type of this member. */ 220 public Object getType() { 221 return (isInvocable() ? getMethodType() : getFieldType()); 222 } 223 224 /** Utility method to produce the signature of this member, 225 * used within the class file format to describe its type. 226 */ 227 public String getSignature() { 228 if (type == null) { 229 expandFromVM(); 230 if (type == null) { 231 return null; 232 } 233 } 234 if (isInvocable()) 235 return BytecodeDescriptor.unparse(getMethodType()); 236 else 237 return BytecodeDescriptor.unparse(getFieldType()); 238 } 239 240 /** Return the modifier flags of this member. 241 * @see java.lang.reflect.Modifier 242 */ 243 public int getModifiers() { 244 return (flags & RECOGNIZED_MODIFIERS); 245 } 246 247 /** Return the reference kind of this member, or zero if none. 248 */ 249 public byte getReferenceKind() { 250 return (byte) ((flags >>> MN_REFERENCE_KIND_SHIFT) & MN_REFERENCE_KIND_MASK); 251 } 252 private boolean referenceKindIsConsistent() { 253 byte refKind = getReferenceKind(); 254 if (refKind == REF_NONE) return isType(); 255 if (isField()) { 256 assert(staticIsConsistent()); 257 assert(MethodHandleNatives.refKindIsField(refKind)); 258 } else if (isConstructor()) { 259 assert(refKind == REF_newInvokeSpecial || refKind == REF_invokeSpecial); 260 } else if (isMethod()) { 261 assert(staticIsConsistent()); 262 assert(MethodHandleNatives.refKindIsMethod(refKind)); 263 if (clazz.isInterface()) 264 assert(refKind == REF_invokeInterface || 265 refKind == REF_invokeStatic || 266 refKind == REF_invokeSpecial || 267 refKind == REF_invokeVirtual && isObjectPublicMethod()); 268 } else { 269 assert(false); 270 } 271 return true; 272 } 273 private boolean isObjectPublicMethod() { 274 if (clazz == Object.class) return true; 275 MethodType mtype = getMethodType(); 276 if (name.equals("toString") && mtype.returnType() == String.class && mtype.parameterCount() == 0) 277 return true; 278 if (name.equals("hashCode") && mtype.returnType() == int.class && mtype.parameterCount() == 0) 279 return true; 280 if (name.equals("equals") && mtype.returnType() == boolean.class && mtype.parameterCount() == 1 && mtype.parameterType(0) == Object.class) 281 return true; 282 return false; 283 } 284 /*non-public*/ boolean referenceKindIsConsistentWith(int originalRefKind) { 285 int refKind = getReferenceKind(); 286 if (refKind == originalRefKind) return true; 287 switch (originalRefKind) { 288 case REF_invokeInterface: 289 // Looking up an interface method, can get (e.g.) Object.hashCode 290 assert(refKind == REF_invokeVirtual || 291 refKind == REF_invokeSpecial) : this; 292 return true; 293 case REF_invokeVirtual: 294 case REF_newInvokeSpecial: 295 // Looked up a virtual, can get (e.g.) final String.hashCode. 296 assert(refKind == REF_invokeSpecial) : this; 297 return true; 298 } 299 assert(false) : this+" != "+MethodHandleNatives.refKindName((byte)originalRefKind); 300 return true; 301 } 302 private boolean staticIsConsistent() { 303 byte refKind = getReferenceKind(); 304 return MethodHandleNatives.refKindIsStatic(refKind) == isStatic() || getModifiers() == 0; 305 } 306 private boolean vminfoIsConsistent() { 307 byte refKind = getReferenceKind(); 308 assert(isResolved()); // else don't call 309 Object vminfo = MethodHandleNatives.getMemberVMInfo(this); 310 assert(vminfo instanceof Object[]); 311 long vmindex = (Long) ((Object[])vminfo)[0]; 312 Object vmtarget = ((Object[])vminfo)[1]; 313 if (MethodHandleNatives.refKindIsField(refKind)) { 314 assert(vmindex >= 0) : vmindex + ":" + this; 315 assert(vmtarget instanceof Class); 316 } else { 317 if (MethodHandleNatives.refKindDoesDispatch(refKind)) 318 assert(vmindex >= 0) : vmindex + ":" + this; 319 else 320 assert(vmindex < 0) : vmindex; 321 assert(vmtarget instanceof MemberName) : vmtarget + " in " + this; 322 } 323 return true; 324 } 325 326 private MemberName changeReferenceKind(byte refKind, byte oldKind) { 327 assert(getReferenceKind() == oldKind); 328 assert(MethodHandleNatives.refKindIsValid(refKind)); 329 flags += (((int)refKind - oldKind) << MN_REFERENCE_KIND_SHIFT); 330 return this; 331 } 332 333 private boolean testFlags(int mask, int value) { 334 return (flags & mask) == value; 335 } 336 private boolean testAllFlags(int mask) { 337 return testFlags(mask, mask); 338 } 339 private boolean testAnyFlags(int mask) { 340 return !testFlags(mask, 0); 341 } 342 343 /** Utility method to query if this member is a method handle invocation (invoke or invokeExact). 344 * Also returns true for the non-public MH.invokeBasic. 345 */ 346 public boolean isMethodHandleInvoke() { 347 final int bits = MH_INVOKE_MODS &~ Modifier.PUBLIC; 348 final int negs = Modifier.STATIC; 349 if (testFlags(bits | negs, bits) && 350 clazz == MethodHandle.class) { 351 return isMethodHandleInvokeName(name); 352 } 353 return false; 354 } 355 public static boolean isMethodHandleInvokeName(String name) { 356 switch (name) { 357 case "invoke": 358 case "invokeExact": 359 case "invokeBasic": // internal sig-poly method 360 return true; 361 default: 362 return false; 363 } 364 } 365 private static final int MH_INVOKE_MODS = Modifier.NATIVE | Modifier.FINAL | Modifier.PUBLIC; 366 367 /** Utility method to query the modifier flags of this member. */ 368 public boolean isStatic() { 369 return Modifier.isStatic(flags); 370 } 371 /** Utility method to query the modifier flags of this member. */ 372 public boolean isPublic() { 373 return Modifier.isPublic(flags); 374 } 375 /** Utility method to query the modifier flags of this member. */ 376 public boolean isPrivate() { 377 return Modifier.isPrivate(flags); 378 } 379 /** Utility method to query the modifier flags of this member. */ 380 public boolean isProtected() { 381 return Modifier.isProtected(flags); 382 } 383 /** Utility method to query the modifier flags of this member. */ 384 public boolean isFinal() { 385 return Modifier.isFinal(flags); 386 } 387 /** Utility method to query whether this member or its defining class is final. */ 388 public boolean canBeStaticallyBound() { 389 return Modifier.isFinal(flags | clazz.getModifiers()); 390 } 391 /** Utility method to query the modifier flags of this member. */ 392 public boolean isVolatile() { 393 return Modifier.isVolatile(flags); 394 } 395 /** Utility method to query the modifier flags of this member. */ 396 public boolean isAbstract() { 397 return Modifier.isAbstract(flags); 398 } 399 /** Utility method to query the modifier flags of this member. */ 400 public boolean isNative() { 401 return Modifier.isNative(flags); 402 } 403 // let the rest (native, volatile, transient, etc.) be tested via Modifier.isFoo 404 405 // unofficial modifier flags, used by HotSpot: 406 static final int BRIDGE = 0x00000040; 407 static final int VARARGS = 0x00000080; 408 static final int SYNTHETIC = 0x00001000; 409 static final int ANNOTATION= 0x00002000; 410 static final int ENUM = 0x00004000; 411 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */ 412 public boolean isBridge() { 413 return testAllFlags(IS_METHOD | BRIDGE); 414 } 415 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */ 416 public boolean isVarargs() { 417 return testAllFlags(VARARGS) && isInvocable(); 418 } 419 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */ 420 public boolean isSynthetic() { 421 return testAllFlags(SYNTHETIC); 422 } 423 424 static final String CONSTRUCTOR_NAME = "<init>"; // the ever-popular 425 426 // modifiers exported by the JVM: 427 static final int RECOGNIZED_MODIFIERS = 0xFFFF; 428 429 // private flags, not part of RECOGNIZED_MODIFIERS: 430 static final int 431 IS_METHOD = MN_IS_METHOD, // method (not constructor) 432 IS_CONSTRUCTOR = MN_IS_CONSTRUCTOR, // constructor 433 IS_FIELD = MN_IS_FIELD, // field 434 IS_TYPE = MN_IS_TYPE, // nested type 435 CALLER_SENSITIVE = MN_CALLER_SENSITIVE; // @CallerSensitive annotation detected 436 437 static final int ALL_ACCESS = Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED; 438 static final int ALL_KINDS = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE; 439 static final int IS_INVOCABLE = IS_METHOD | IS_CONSTRUCTOR; 440 static final int IS_FIELD_OR_METHOD = IS_METHOD | IS_FIELD; 441 static final int SEARCH_ALL_SUPERS = MN_SEARCH_SUPERCLASSES | MN_SEARCH_INTERFACES; 442 443 /** Utility method to query whether this member is a method or constructor. */ 444 public boolean isInvocable() { 445 return testAnyFlags(IS_INVOCABLE); 446 } 447 /** Utility method to query whether this member is a method, constructor, or field. */ 448 public boolean isFieldOrMethod() { 449 return testAnyFlags(IS_FIELD_OR_METHOD); 450 } 451 /** Query whether this member is a method. */ 452 public boolean isMethod() { 453 return testAllFlags(IS_METHOD); 454 } 455 /** Query whether this member is a constructor. */ 456 public boolean isConstructor() { 457 return testAllFlags(IS_CONSTRUCTOR); 458 } 459 /** Query whether this member is a field. */ 460 public boolean isField() { 461 return testAllFlags(IS_FIELD); 462 } 463 /** Query whether this member is a type. */ 464 public boolean isType() { 465 return testAllFlags(IS_TYPE); 466 } 467 /** Utility method to query whether this member is neither public, private, nor protected. */ 468 public boolean isPackage() { 469 return !testAnyFlags(ALL_ACCESS); 470 } 471 /** Query whether this member has a CallerSensitive annotation. */ 472 public boolean isCallerSensitive() { 473 return testAllFlags(CALLER_SENSITIVE); 474 } 475 476 /** Utility method to query whether this member is accessible from a given lookup class. */ 477 public boolean isAccessibleFrom(Class<?> lookupClass) { 478 return VerifyAccess.isMemberAccessible(this.getDeclaringClass(), this.getDeclaringClass(), flags, 479 lookupClass, ALL_ACCESS|MethodHandles.Lookup.PACKAGE); 480 } 481 482 /** Initialize a query. It is not resolved. */ 483 private void init(Class<?> defClass, String name, Object type, int flags) { 484 // defining class is allowed to be null (for a naked name/type pair) 485 //name.toString(); // null check 486 //type.equals(type); // null check 487 // fill in fields: 488 this.clazz = defClass; 489 this.name = name; 490 this.type = type; 491 this.flags = flags; 492 assert(testAnyFlags(ALL_KINDS)); 493 assert(this.resolution == null); // nobody should have touched this yet 494 //assert(referenceKindIsConsistent()); // do this after resolution 495 } 496 497 /** 498 * Calls down to the VM to fill in the fields. This method is 499 * synchronized to avoid racing calls. 500 */ 501 private void expandFromVM() { 502 if (type != null) { 503 return; 504 } 505 if (!isResolved()) { 506 return; 507 } 508 MethodHandleNatives.expand(this); 509 } 510 511 // Capturing information from the Core Reflection API: 512 private static int flagsMods(int flags, int mods, byte refKind) { 513 assert((flags & RECOGNIZED_MODIFIERS) == 0); 514 assert((mods & ~RECOGNIZED_MODIFIERS) == 0); 515 assert((refKind & ~MN_REFERENCE_KIND_MASK) == 0); 516 return flags | mods | (refKind << MN_REFERENCE_KIND_SHIFT); 517 } 518 /** Create a name for the given reflected method. The resulting name will be in a resolved state. */ 519 public MemberName(Method m) { 520 this(m, false); 521 } 522 @SuppressWarnings("LeakingThisInConstructor") 523 public MemberName(Method m, boolean wantSpecial) { 524 m.getClass(); // NPE check 525 // fill in vmtarget, vmindex while we have m in hand: 526 MethodHandleNatives.init(this, m); 527 if (clazz == null) { // MHN.init failed 528 if (m.getDeclaringClass() == MethodHandle.class && 529 isMethodHandleInvokeName(m.getName())) { 530 // The JVM did not reify this signature-polymorphic instance. 531 // Need a special case here. 532 // See comments on MethodHandleNatives.linkMethod. 533 MethodType type = MethodType.methodType(m.getReturnType(), m.getParameterTypes()); 534 int flags = flagsMods(IS_METHOD, m.getModifiers(), REF_invokeVirtual); 535 init(MethodHandle.class, m.getName(), type, flags); 536 if (isMethodHandleInvoke()) 537 return; 538 } 539 throw new LinkageError(m.toString()); 540 } 541 assert(isResolved() && this.clazz != null); 542 this.name = m.getName(); 543 if (this.type == null) 544 this.type = new Object[] { m.getReturnType(), m.getParameterTypes() }; 545 if (wantSpecial) { 546 if (isAbstract()) 547 throw new AbstractMethodError(this.toString()); 548 if (getReferenceKind() == REF_invokeVirtual) 549 changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual); 550 else if (getReferenceKind() == REF_invokeInterface) 551 // invokeSpecial on a default method 552 changeReferenceKind(REF_invokeSpecial, REF_invokeInterface); 553 } 554 } 555 public MemberName asSpecial() { 556 switch (getReferenceKind()) { 557 case REF_invokeSpecial: return this; 558 case REF_invokeVirtual: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual); 559 case REF_invokeInterface: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeInterface); 560 case REF_newInvokeSpecial: return clone().changeReferenceKind(REF_invokeSpecial, REF_newInvokeSpecial); 561 } 562 throw new IllegalArgumentException(this.toString()); 563 } 564 /** If this MN is not REF_newInvokeSpecial, return a clone with that ref. kind. 565 * In that case it must already be REF_invokeSpecial. 566 */ 567 public MemberName asConstructor() { 568 switch (getReferenceKind()) { 569 case REF_invokeSpecial: return clone().changeReferenceKind(REF_newInvokeSpecial, REF_invokeSpecial); 570 case REF_newInvokeSpecial: return this; 571 } 572 throw new IllegalArgumentException(this.toString()); 573 } 574 /** If this MN is a REF_invokeSpecial, return a clone with the "normal" kind 575 * REF_invokeVirtual; also switch either to REF_invokeInterface if clazz.isInterface. 576 * The end result is to get a fully virtualized version of the MN. 577 * (Note that resolving in the JVM will sometimes devirtualize, changing 578 * REF_invokeVirtual of a final to REF_invokeSpecial, and REF_invokeInterface 579 * in some corner cases to either of the previous two; this transform 580 * undoes that change under the assumption that it occurred.) 581 */ 582 public MemberName asNormalOriginal() { 583 byte normalVirtual = clazz.isInterface() ? REF_invokeInterface : REF_invokeVirtual; 584 byte refKind = getReferenceKind(); 585 byte newRefKind = refKind; 586 MemberName result = this; 587 switch (refKind) { 588 case REF_invokeInterface: 589 case REF_invokeVirtual: 590 case REF_invokeSpecial: 591 newRefKind = normalVirtual; 592 break; 593 } 594 if (newRefKind == refKind) 595 return this; 596 result = clone().changeReferenceKind(newRefKind, refKind); 597 assert(this.referenceKindIsConsistentWith(result.getReferenceKind())); 598 return result; 599 } 600 /** Create a name for the given reflected constructor. The resulting name will be in a resolved state. */ 601 @SuppressWarnings("LeakingThisInConstructor") 602 public MemberName(Constructor<?> ctor) { 603 ctor.getClass(); // NPE check 604 // fill in vmtarget, vmindex while we have ctor in hand: 605 MethodHandleNatives.init(this, ctor); 606 assert(isResolved() && this.clazz != null); 607 this.name = CONSTRUCTOR_NAME; 608 if (this.type == null) 609 this.type = new Object[] { void.class, ctor.getParameterTypes() }; 610 } 611 /** Create a name for the given reflected field. The resulting name will be in a resolved state. 612 */ 613 public MemberName(Field fld) { 614 this(fld, false); 615 } 616 @SuppressWarnings("LeakingThisInConstructor") 617 public MemberName(Field fld, boolean makeSetter) { 618 fld.getClass(); // NPE check 619 // fill in vmtarget, vmindex while we have fld in hand: 620 MethodHandleNatives.init(this, fld); 621 assert(isResolved() && this.clazz != null); 622 this.name = fld.getName(); 623 this.type = fld.getType(); 624 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField)); 625 byte refKind = this.getReferenceKind(); 626 assert(refKind == (isStatic() ? REF_getStatic : REF_getField)); 627 if (makeSetter) { 628 changeReferenceKind((byte)(refKind + (REF_putStatic - REF_getStatic)), refKind); 629 } 630 } 631 public boolean isGetter() { 632 return MethodHandleNatives.refKindIsGetter(getReferenceKind()); 633 } 634 public boolean isSetter() { 635 return MethodHandleNatives.refKindIsSetter(getReferenceKind()); 636 } 637 public MemberName asSetter() { 638 byte refKind = getReferenceKind(); 639 assert(MethodHandleNatives.refKindIsGetter(refKind)); 640 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField)); 641 byte setterRefKind = (byte)(refKind + (REF_putField - REF_getField)); 642 return clone().changeReferenceKind(setterRefKind, refKind); 643 } 644 /** Create a name for the given class. The resulting name will be in a resolved state. */ 645 public MemberName(Class<?> type) { 646 init(type.getDeclaringClass(), type.getSimpleName(), type, 647 flagsMods(IS_TYPE, type.getModifiers(), REF_NONE)); 648 initResolved(true); 649 } 650 651 /** 652 * Create a name for a signature-polymorphic invoker. 653 * This is a placeholder for a signature-polymorphic instance 654 * (of MH.invokeExact, etc.) that the JVM does not reify. 655 * See comments on {@link MethodHandleNatives#linkMethod}. 656 */ 657 static MemberName makeMethodHandleInvoke(String name, MethodType type) { 658 return makeMethodHandleInvoke(name, type, MH_INVOKE_MODS | SYNTHETIC); 659 } 660 static MemberName makeMethodHandleInvoke(String name, MethodType type, int mods) { 661 MemberName mem = new MemberName(MethodHandle.class, name, type, REF_invokeVirtual); 662 mem.flags |= mods; // it's not resolved, but add these modifiers anyway 663 assert(mem.isMethodHandleInvoke()) : mem; 664 return mem; 665 } 666 667 // bare-bones constructor; the JVM will fill it in 668 MemberName() { } 669 670 // locally useful cloner 671 @Override protected MemberName clone() { 672 try { 673 return (MemberName) super.clone(); 674 } catch (CloneNotSupportedException ex) { 675 throw newInternalError(ex); 676 } 677 } 678 679 /** Get the definition of this member name. 680 * This may be in a super-class of the declaring class of this member. 681 */ 682 public MemberName getDefinition() { 683 if (!isResolved()) throw new IllegalStateException("must be resolved: "+this); 684 if (isType()) return this; 685 MemberName res = this.clone(); 686 res.clazz = null; 687 res.type = null; 688 res.name = null; 689 res.resolution = res; 690 res.expandFromVM(); 691 assert(res.getName().equals(this.getName())); 692 return res; 693 } 694 695 @Override 696 public int hashCode() { 697 return Objects.hash(clazz, getReferenceKind(), name, getType()); 698 } 699 @Override 700 public boolean equals(Object that) { 701 return (that instanceof MemberName && this.equals((MemberName)that)); 702 } 703 704 /** Decide if two member names have exactly the same symbolic content. 705 * Does not take into account any actual class members, so even if 706 * two member names resolve to the same actual member, they may 707 * be distinct references. 708 */ 709 public boolean equals(MemberName that) { 710 if (this == that) return true; 711 if (that == null) return false; 712 return this.clazz == that.clazz 713 && this.getReferenceKind() == that.getReferenceKind() 714 && Objects.equals(this.name, that.name) 715 && Objects.equals(this.getType(), that.getType()); 716 } 717 718 // Construction from symbolic parts, for queries: 719 /** Create a field or type name from the given components: 720 * Declaring class, name, type, reference kind. 721 * The declaring class may be supplied as null if this is to be a bare name and type. 722 * The resulting name will in an unresolved state. 723 */ 724 public MemberName(Class<?> defClass, String name, Class<?> type, byte refKind) { 725 init(defClass, name, type, flagsMods(IS_FIELD, 0, refKind)); 726 initResolved(false); 727 } 728 /** Create a method or constructor name from the given components: 729 * Declaring class, name, type, reference kind. 730 * It will be a constructor if and only if the name is {@code "<init>"}. 731 * The declaring class may be supplied as null if this is to be a bare name and type. 732 * The last argument is optional, a boolean which requests REF_invokeSpecial. 733 * The resulting name will in an unresolved state. 734 */ 735 public MemberName(Class<?> defClass, String name, MethodType type, byte refKind) { 736 int initFlags = (name != null && name.equals(CONSTRUCTOR_NAME) ? IS_CONSTRUCTOR : IS_METHOD); 737 init(defClass, name, type, flagsMods(initFlags, 0, refKind)); 738 initResolved(false); 739 } 740 /** Create a method, constructor, or field name from the given components: 741 * Reference kind, declaring class, name, type. 742 */ 743 public MemberName(byte refKind, Class<?> defClass, String name, Object type) { 744 int kindFlags; 745 if (MethodHandleNatives.refKindIsField(refKind)) { 746 kindFlags = IS_FIELD; 747 if (!(type instanceof Class)) 748 throw newIllegalArgumentException("not a field type"); 749 } else if (MethodHandleNatives.refKindIsMethod(refKind)) { 750 kindFlags = IS_METHOD; 751 if (!(type instanceof MethodType)) 752 throw newIllegalArgumentException("not a method type"); 753 } else if (refKind == REF_newInvokeSpecial) { 754 kindFlags = IS_CONSTRUCTOR; 755 if (!(type instanceof MethodType) || 756 !CONSTRUCTOR_NAME.equals(name)) 757 throw newIllegalArgumentException("not a constructor type or name"); 758 } else { 759 throw newIllegalArgumentException("bad reference kind "+refKind); 760 } 761 init(defClass, name, type, flagsMods(kindFlags, 0, refKind)); 762 initResolved(false); 763 } 764 /** Query whether this member name is resolved to a non-static, non-final method. 765 */ 766 public boolean hasReceiverTypeDispatch() { 767 return MethodHandleNatives.refKindDoesDispatch(getReferenceKind()); 768 } 769 770 /** Query whether this member name is resolved. 771 * A resolved member name is one for which the JVM has found 772 * a method, constructor, field, or type binding corresponding exactly to the name. 773 * (Document?) 774 */ 775 public boolean isResolved() { 776 return resolution == null; 777 } 778 779 private void initResolved(boolean isResolved) { 780 assert(this.resolution == null); // not initialized yet! 781 if (!isResolved) 782 this.resolution = this; 783 assert(isResolved() == isResolved); 784 } 785 786 void checkForTypeAlias() { 787 if (isInvocable()) { 788 MethodType type; 789 if (this.type instanceof MethodType) 790 type = (MethodType) this.type; 791 else 792 this.type = type = getMethodType(); 793 if (type.erase() == type) return; 794 if (VerifyAccess.isTypeVisible(type, clazz)) return; 795 throw new LinkageError("bad method type alias: "+type+" not visible from "+clazz); 796 } else { 797 Class<?> type; 798 if (this.type instanceof Class<?>) 799 type = (Class<?>) this.type; 800 else 801 this.type = type = getFieldType(); 802 if (VerifyAccess.isTypeVisible(type, clazz)) return; 803 throw new LinkageError("bad field type alias: "+type+" not visible from "+clazz); 804 } 805 } 806 807 808 /** Produce a string form of this member name. 809 * For types, it is simply the type's own string (as reported by {@code toString}). 810 * For fields, it is {@code "DeclaringClass.name/type"}. 811 * For methods and constructors, it is {@code "DeclaringClass.name(ptype...)rtype"}. 812 * If the declaring class is null, the prefix {@code "DeclaringClass."} is omitted. 813 * If the member is unresolved, a prefix {@code "*."} is prepended. 814 */ 815 @SuppressWarnings("LocalVariableHidesMemberVariable") 816 @Override 817 public String toString() { 818 if (isType()) 819 return type.toString(); // class java.lang.String 820 // else it is a field, method, or constructor 821 StringBuilder buf = new StringBuilder(); 822 if (getDeclaringClass() != null) { 823 buf.append(getName(clazz)); 824 buf.append('.'); 825 } 826 String name = getName(); 827 buf.append(name == null ? "*" : name); 828 Object type = getType(); 829 if (!isInvocable()) { 830 buf.append('/'); 831 buf.append(type == null ? "*" : getName(type)); 832 } else { 833 buf.append(type == null ? "(*)*" : getName(type)); 834 } 835 byte refKind = getReferenceKind(); 836 if (refKind != REF_NONE) { 837 buf.append('/'); 838 buf.append(MethodHandleNatives.refKindName(refKind)); 839 } 840 //buf.append("#").append(System.identityHashCode(this)); 841 return buf.toString(); 842 } 843 private static String getName(Object obj) { 844 if (obj instanceof Class<?>) 845 return ((Class<?>)obj).getName(); 846 return String.valueOf(obj); 847 } 848 849 public IllegalAccessException makeAccessException(String message, Object from) { 850 message = message + ": "+ toString(); 851 if (from != null) message += ", from " + from; 852 return new IllegalAccessException(message); 853 } 854 private String message() { 855 if (isResolved()) 856 return "no access"; 857 else if (isConstructor()) 858 return "no such constructor"; 859 else if (isMethod()) 860 return "no such method"; 861 else 862 return "no such field"; 863 } 864 public ReflectiveOperationException makeAccessException() { 865 String message = message() + ": "+ toString(); 866 ReflectiveOperationException ex; 867 if (isResolved() || !(resolution instanceof NoSuchMethodError || 868 resolution instanceof NoSuchFieldError)) 869 ex = new IllegalAccessException(message); 870 else if (isConstructor()) 871 ex = new NoSuchMethodException(message); 872 else if (isMethod()) 873 ex = new NoSuchMethodException(message); 874 else 875 ex = new NoSuchFieldException(message); 876 if (resolution instanceof Throwable) 877 ex.initCause((Throwable) resolution); 878 return ex; 879 } 880 881 /** Actually making a query requires an access check. */ 882 /*non-public*/ static Factory getFactory() { 883 return Factory.INSTANCE; 884 } 885 /** A factory type for resolving member names with the help of the VM. 886 * TBD: Define access-safe public constructors for this factory. 887 */ 888 /*non-public*/ static class Factory { 889 private Factory() { } // singleton pattern 890 static Factory INSTANCE = new Factory(); 891 892 private static int ALLOWED_FLAGS = ALL_KINDS; 893 894 /// Queries 895 List<MemberName> getMembers(Class<?> defc, 896 String matchName, Object matchType, 897 int matchFlags, Class<?> lookupClass) { 898 matchFlags &= ALLOWED_FLAGS; 899 String matchSig = null; 900 if (matchType != null) { 901 matchSig = BytecodeDescriptor.unparse(matchType); 902 if (matchSig.startsWith("(")) 903 matchFlags &= ~(ALL_KINDS & ~IS_INVOCABLE); 904 else 905 matchFlags &= ~(ALL_KINDS & ~IS_FIELD); 906 } 907 final int BUF_MAX = 0x2000; 908 int len1 = matchName == null ? 10 : matchType == null ? 4 : 1; 909 MemberName[] buf = newMemberBuffer(len1); 910 int totalCount = 0; 911 ArrayList<MemberName[]> bufs = null; 912 int bufCount = 0; 913 for (;;) { 914 bufCount = MethodHandleNatives.getMembers(defc, 915 matchName, matchSig, matchFlags, 916 lookupClass, 917 totalCount, buf); 918 if (bufCount <= buf.length) { 919 if (bufCount < 0) bufCount = 0; 920 totalCount += bufCount; 921 break; 922 } 923 // JVM returned to us with an intentional overflow! 924 totalCount += buf.length; 925 int excess = bufCount - buf.length; 926 if (bufs == null) bufs = new ArrayList<>(1); 927 bufs.add(buf); 928 int len2 = buf.length; 929 len2 = Math.max(len2, excess); 930 len2 = Math.max(len2, totalCount / 4); 931 buf = newMemberBuffer(Math.min(BUF_MAX, len2)); 932 } 933 ArrayList<MemberName> result = new ArrayList<>(totalCount); 934 if (bufs != null) { 935 for (MemberName[] buf0 : bufs) { 936 Collections.addAll(result, buf0); 937 } 938 } 939 result.addAll(Arrays.asList(buf).subList(0, bufCount)); 940 // Signature matching is not the same as type matching, since 941 // one signature might correspond to several types. 942 // So if matchType is a Class or MethodType, refilter the results. 943 if (matchType != null && matchType != matchSig) { 944 for (Iterator<MemberName> it = result.iterator(); it.hasNext();) { 945 MemberName m = it.next(); 946 if (!matchType.equals(m.getType())) 947 it.remove(); 948 } 949 } 950 return result; 951 } 952 /** Produce a resolved version of the given member. 953 * Super types are searched (for inherited members) if {@code searchSupers} is true. 954 * Access checking is performed on behalf of the given {@code lookupClass}. 955 * If lookup fails or access is not permitted, null is returned. 956 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in. 957 */ 958 private MemberName resolve(byte refKind, MemberName ref, Class<?> lookupClass) { 959 MemberName m = ref.clone(); // JVM will side-effect the ref 960 assert(refKind == m.getReferenceKind()); 961 try { 962 m = MethodHandleNatives.resolve(m, lookupClass); 963 m.checkForTypeAlias(); 964 m.resolution = null; 965 } catch (LinkageError ex) { 966 // JVM reports that the "bytecode behavior" would get an error 967 assert(!m.isResolved()); 968 m.resolution = ex; 969 return m; 970 } 971 assert(m.referenceKindIsConsistent()); 972 m.initResolved(true); 973 assert(m.vminfoIsConsistent()); 974 return m; 975 } 976 /** Produce a resolved version of the given member. 977 * Super types are searched (for inherited members) if {@code searchSupers} is true. 978 * Access checking is performed on behalf of the given {@code lookupClass}. 979 * If lookup fails or access is not permitted, a {@linkplain ReflectiveOperationException} is thrown. 980 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in. 981 */ 982 public 983 <NoSuchMemberException extends ReflectiveOperationException> 984 MemberName resolveOrFail(byte refKind, MemberName m, Class<?> lookupClass, 985 Class<NoSuchMemberException> nsmClass) 986 throws IllegalAccessException, NoSuchMemberException { 987 MemberName result = resolve(refKind, m, lookupClass); 988 if (result.isResolved()) 989 return result; 990 ReflectiveOperationException ex = result.makeAccessException(); 991 if (ex instanceof IllegalAccessException) throw (IllegalAccessException) ex; 992 throw nsmClass.cast(ex); 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, return null. 998 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in. 999 */ 1000 public 1001 MemberName resolveOrNull(byte refKind, MemberName m, Class<?> lookupClass) { 1002 MemberName result = resolve(refKind, m, lookupClass); 1003 if (result.isResolved()) 1004 return result; 1005 return null; 1006 } 1007 /** Return a list of all methods defined by the given class. 1008 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1009 * Access checking is performed on behalf of the given {@code lookupClass}. 1010 * Inaccessible members are not added to the last. 1011 */ 1012 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers, 1013 Class<?> lookupClass) { 1014 return getMethods(defc, searchSupers, null, null, lookupClass); 1015 } 1016 /** Return a list of matching methods defined by the given class. 1017 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1018 * Returned methods will match the name (if not null) and the type (if not null). 1019 * Access checking is performed on behalf of the given {@code lookupClass}. 1020 * Inaccessible members are not added to the last. 1021 */ 1022 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers, 1023 String name, MethodType type, Class<?> lookupClass) { 1024 int matchFlags = IS_METHOD | (searchSupers ? SEARCH_ALL_SUPERS : 0); 1025 return getMembers(defc, name, type, matchFlags, lookupClass); 1026 } 1027 /** Return a list of all constructors defined by the given class. 1028 * Access checking is performed on behalf of the given {@code lookupClass}. 1029 * Inaccessible members are not added to the last. 1030 */ 1031 public List<MemberName> getConstructors(Class<?> defc, Class<?> lookupClass) { 1032 return getMembers(defc, null, null, IS_CONSTRUCTOR, lookupClass); 1033 } 1034 /** Return a list of all fields defined by the given class. 1035 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1036 * Access checking is performed on behalf of the given {@code lookupClass}. 1037 * Inaccessible members are not added to the last. 1038 */ 1039 public List<MemberName> getFields(Class<?> defc, boolean searchSupers, 1040 Class<?> lookupClass) { 1041 return getFields(defc, searchSupers, null, null, lookupClass); 1042 } 1043 /** Return a list of all fields defined by the given class. 1044 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1045 * Returned fields will match the name (if not null) and the type (if not null). 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> getFields(Class<?> defc, boolean searchSupers, 1050 String name, Class<?> type, Class<?> lookupClass) { 1051 int matchFlags = IS_FIELD | (searchSupers ? SEARCH_ALL_SUPERS : 0); 1052 return getMembers(defc, name, type, matchFlags, lookupClass); 1053 } 1054 /** Return a list of all nested types defined by the given class. 1055 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1056 * Access checking is performed on behalf of the given {@code lookupClass}. 1057 * Inaccessible members are not added to the last. 1058 */ 1059 public List<MemberName> getNestedTypes(Class<?> defc, boolean searchSupers, 1060 Class<?> lookupClass) { 1061 int matchFlags = IS_TYPE | (searchSupers ? SEARCH_ALL_SUPERS : 0); 1062 return getMembers(defc, null, null, matchFlags, lookupClass); 1063 } 1064 private static MemberName[] newMemberBuffer(int length) { 1065 MemberName[] buf = new MemberName[length]; 1066 // fill the buffer with dummy structs for the JVM to fill in 1067 for (int i = 0; i < length; i++) 1068 buf[i] = new MemberName(); 1069 return buf; 1070 } 1071 } 1072 1073 // static { 1074 // System.out.println("Hello world! My methods are:"); 1075 // System.out.println(Factory.INSTANCE.getMethods(MemberName.class, true, null)); 1076 // } 1077 }