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 // if (isConstructor() && refKind != REF_newInvokeSpecial) 331 // flags += (IS_METHOD - IS_CONSTRUCTOR); 332 // else if (refKind == REF_newInvokeSpecial && isMethod()) 333 // flags += (IS_CONSTRUCTOR - IS_METHOD); 334 return this; 335 } 336 337 private boolean testFlags(int mask, int value) { 338 return (flags & mask) == value; 339 } 340 private boolean testAllFlags(int mask) { 341 return testFlags(mask, mask); 342 } 343 private boolean testAnyFlags(int mask) { 344 return !testFlags(mask, 0); 345 } 346 347 /** Utility method to query if this member is a method handle invocation (invoke or invokeExact). */ 348 public boolean isMethodHandleInvoke() { 349 final int bits = MH_INVOKE_MODS; 350 final int negs = Modifier.STATIC; 351 if (testFlags(bits | negs, bits) && 352 clazz == MethodHandle.class) { 353 return isMethodHandleInvokeName(name); 354 } 355 return false; 356 } 357 public static boolean isMethodHandleInvokeName(String name) { 358 return name.equals("invoke") || name.equals("invokeExact"); 359 } 360 private static final int MH_INVOKE_MODS = Modifier.NATIVE | Modifier.FINAL | Modifier.PUBLIC; 361 362 /** Utility method to query the modifier flags of this member. */ 363 public boolean isStatic() { 364 return Modifier.isStatic(flags); 365 } 366 /** Utility method to query the modifier flags of this member. */ 367 public boolean isPublic() { 368 return Modifier.isPublic(flags); 369 } 370 /** Utility method to query the modifier flags of this member. */ 371 public boolean isPrivate() { 372 return Modifier.isPrivate(flags); 373 } 374 /** Utility method to query the modifier flags of this member. */ 375 public boolean isProtected() { 376 return Modifier.isProtected(flags); 377 } 378 /** Utility method to query the modifier flags of this member. */ 379 public boolean isFinal() { 380 return Modifier.isFinal(flags); 381 } 382 /** Utility method to query whether this member or its defining class is final. */ 383 public boolean canBeStaticallyBound() { 384 return Modifier.isFinal(flags | clazz.getModifiers()); 385 } 386 /** Utility method to query the modifier flags of this member. */ 387 public boolean isVolatile() { 388 return Modifier.isVolatile(flags); 389 } 390 /** Utility method to query the modifier flags of this member. */ 391 public boolean isAbstract() { 392 return Modifier.isAbstract(flags); 393 } 394 /** Utility method to query the modifier flags of this member. */ 395 public boolean isNative() { 396 return Modifier.isNative(flags); 397 } 398 // let the rest (native, volatile, transient, etc.) be tested via Modifier.isFoo 399 400 // unofficial modifier flags, used by HotSpot: 401 static final int BRIDGE = 0x00000040; 402 static final int VARARGS = 0x00000080; 403 static final int SYNTHETIC = 0x00001000; 404 static final int ANNOTATION= 0x00002000; 405 static final int ENUM = 0x00004000; 406 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */ 407 public boolean isBridge() { 408 return testAllFlags(IS_METHOD | BRIDGE); 409 } 410 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */ 411 public boolean isVarargs() { 412 return testAllFlags(VARARGS) && isInvocable(); 413 } 414 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */ 415 public boolean isSynthetic() { 416 return testAllFlags(SYNTHETIC); 417 } 418 419 static final String CONSTRUCTOR_NAME = "<init>"; // the ever-popular 420 421 // modifiers exported by the JVM: 422 static final int RECOGNIZED_MODIFIERS = 0xFFFF; 423 424 // private flags, not part of RECOGNIZED_MODIFIERS: 425 static final int 426 IS_METHOD = MN_IS_METHOD, // method (not constructor) 427 IS_CONSTRUCTOR = MN_IS_CONSTRUCTOR, // constructor 428 IS_FIELD = MN_IS_FIELD, // field 429 IS_TYPE = MN_IS_TYPE, // nested type 430 CALLER_SENSITIVE = MN_CALLER_SENSITIVE; // @CallerSensitive annotation detected 431 432 static final int ALL_ACCESS = Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED; 433 static final int ALL_KINDS = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE; 434 static final int IS_INVOCABLE = IS_METHOD | IS_CONSTRUCTOR; 435 static final int IS_FIELD_OR_METHOD = IS_METHOD | IS_FIELD; 436 static final int SEARCH_ALL_SUPERS = MN_SEARCH_SUPERCLASSES | MN_SEARCH_INTERFACES; 437 438 /** Utility method to query whether this member is a method or constructor. */ 439 public boolean isInvocable() { 440 return testAnyFlags(IS_INVOCABLE); 441 } 442 /** Utility method to query whether this member is a method, constructor, or field. */ 443 public boolean isFieldOrMethod() { 444 return testAnyFlags(IS_FIELD_OR_METHOD); 445 } 446 /** Query whether this member is a method. */ 447 public boolean isMethod() { 448 return testAllFlags(IS_METHOD); 449 } 450 /** Query whether this member is a constructor. */ 451 public boolean isConstructor() { 452 return testAllFlags(IS_CONSTRUCTOR); 453 } 454 /** Query whether this member is a field. */ 455 public boolean isField() { 456 return testAllFlags(IS_FIELD); 457 } 458 /** Query whether this member is a type. */ 459 public boolean isType() { 460 return testAllFlags(IS_TYPE); 461 } 462 /** Utility method to query whether this member is neither public, private, nor protected. */ 463 public boolean isPackage() { 464 return !testAnyFlags(ALL_ACCESS); 465 } 466 /** Query whether this member has a CallerSensitive annotation. */ 467 public boolean isCallerSensitive() { 468 return testAllFlags(CALLER_SENSITIVE); 469 } 470 471 /** Utility method to query whether this member is accessible from a given lookup class. */ 472 public boolean isAccessibleFrom(Class<?> lookupClass) { 473 return VerifyAccess.isMemberAccessible(this.getDeclaringClass(), this.getDeclaringClass(), flags, 474 lookupClass, ALL_ACCESS|MethodHandles.Lookup.PACKAGE); 475 } 476 477 /** Initialize a query. It is not resolved. */ 478 private void init(Class<?> defClass, String name, Object type, int flags) { 479 // defining class is allowed to be null (for a naked name/type pair) 480 //name.toString(); // null check 481 //type.equals(type); // null check 482 // fill in fields: 483 this.clazz = defClass; 484 this.name = name; 485 this.type = type; 486 this.flags = flags; 487 assert(testAnyFlags(ALL_KINDS)); 488 assert(this.resolution == null); // nobody should have touched this yet 489 //assert(referenceKindIsConsistent()); // do this after resolution 490 } 491 492 /** 493 * Calls down to the VM to fill in the fields. This method is 494 * synchronized to avoid racing calls. 495 */ 496 private void expandFromVM() { 497 if (type != null) { 498 return; 499 } 500 if (!isResolved()) { 501 return; 502 } 503 MethodHandleNatives.expand(this); 504 } 505 506 // Capturing information from the Core Reflection API: 507 private static int flagsMods(int flags, int mods, byte refKind) { 508 assert((flags & RECOGNIZED_MODIFIERS) == 0); 509 assert((mods & ~RECOGNIZED_MODIFIERS) == 0); 510 assert((refKind & ~MN_REFERENCE_KIND_MASK) == 0); 511 return flags | mods | (refKind << MN_REFERENCE_KIND_SHIFT); 512 } 513 /** Create a name for the given reflected method. The resulting name will be in a resolved state. */ 514 public MemberName(Method m) { 515 this(m, false); 516 } 517 @SuppressWarnings("LeakingThisInConstructor") 518 public MemberName(Method m, boolean wantSpecial) { 519 m.getClass(); // NPE check 520 // fill in vmtarget, vmindex while we have m in hand: 521 MethodHandleNatives.init(this, m); 522 if (clazz == null) { // MHN.init failed 523 if (m.getDeclaringClass() == MethodHandle.class && 524 isMethodHandleInvokeName(m.getName())) { 525 // The JVM did not reify this signature-polymorphic instance. 526 // Need a special case here. 527 // See comments on MethodHandleNatives.linkMethod. 528 MethodType type = MethodType.methodType(m.getReturnType(), m.getParameterTypes()); 529 int flags = flagsMods(IS_METHOD, m.getModifiers(), REF_invokeVirtual); 530 init(MethodHandle.class, m.getName(), type, flags); 531 if (isMethodHandleInvoke()) 532 return; 533 } 534 throw new LinkageError(m.toString()); 535 } 536 assert(isResolved() && this.clazz != null); 537 this.name = m.getName(); 538 if (this.type == null) 539 this.type = new Object[] { m.getReturnType(), m.getParameterTypes() }; 540 if (wantSpecial) { 541 if (isAbstract()) 542 throw new AbstractMethodError(this.toString()); 543 if (getReferenceKind() == REF_invokeVirtual) 544 changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual); 545 else if (getReferenceKind() == REF_invokeInterface) 546 // invokeSpecial on a default method 547 changeReferenceKind(REF_invokeSpecial, REF_invokeInterface); 548 } 549 } 550 public MemberName asSpecial() { 551 switch (getReferenceKind()) { 552 case REF_invokeSpecial: return this; 553 case REF_invokeVirtual: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual); 554 case REF_invokeInterface: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeInterface); 555 case REF_newInvokeSpecial: return clone().changeReferenceKind(REF_invokeSpecial, REF_newInvokeSpecial); 556 } 557 throw new IllegalArgumentException(this.toString()); 558 } 559 /** If this MN is not REF_newInvokeSpecial, return a clone with that ref. kind. 560 * In that case it must already be REF_invokeSpecial. 561 */ 562 public MemberName asConstructor() { 563 switch (getReferenceKind()) { 564 case REF_invokeSpecial: return clone().changeReferenceKind(REF_newInvokeSpecial, REF_invokeSpecial); 565 case REF_newInvokeSpecial: return this; 566 } 567 throw new IllegalArgumentException(this.toString()); 568 } 569 /** If this MN is a REF_invokeSpecial, return a clone with the "normal" kind 570 * REF_invokeVirtual; also switch either to REF_invokeInterface if clazz.isInterface. 571 * The end result is to get a fully virtualized version of the MN. 572 * (Note that resolving in the JVM will sometimes devirtualize, changing 573 * REF_invokeVirtual of a final to REF_invokeSpecial, and REF_invokeInterface 574 * in some corner cases to either of the previous two; this transform 575 * undoes that change under the assumption that it occurred.) 576 */ 577 public MemberName asNormalOriginal() { 578 byte normalVirtual = clazz.isInterface() ? REF_invokeInterface : REF_invokeVirtual; 579 byte refKind = getReferenceKind(); 580 byte newRefKind = refKind; 581 MemberName result = this; 582 switch (refKind) { 583 case REF_invokeInterface: 584 case REF_invokeVirtual: 585 case REF_invokeSpecial: 586 newRefKind = normalVirtual; 587 break; 588 } 589 if (newRefKind == refKind) 590 return this; 591 result = clone().changeReferenceKind(newRefKind, refKind); 592 assert(this.referenceKindIsConsistentWith(result.getReferenceKind())); 593 return result; 594 } 595 /** Create a name for the given reflected constructor. The resulting name will be in a resolved state. */ 596 @SuppressWarnings("LeakingThisInConstructor") 597 public MemberName(Constructor<?> ctor) { 598 ctor.getClass(); // NPE check 599 // fill in vmtarget, vmindex while we have ctor in hand: 600 MethodHandleNatives.init(this, ctor); 601 assert(isResolved() && this.clazz != null); 602 this.name = CONSTRUCTOR_NAME; 603 if (this.type == null) 604 this.type = new Object[] { void.class, ctor.getParameterTypes() }; 605 } 606 /** Create a name for the given reflected field. The resulting name will be in a resolved state. 607 */ 608 public MemberName(Field fld) { 609 this(fld, false); 610 } 611 @SuppressWarnings("LeakingThisInConstructor") 612 public MemberName(Field fld, boolean makeSetter) { 613 fld.getClass(); // NPE check 614 // fill in vmtarget, vmindex while we have fld in hand: 615 MethodHandleNatives.init(this, fld); 616 assert(isResolved() && this.clazz != null); 617 this.name = fld.getName(); 618 this.type = fld.getType(); 619 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField)); 620 byte refKind = this.getReferenceKind(); 621 assert(refKind == (isStatic() ? REF_getStatic : REF_getField)); 622 if (makeSetter) { 623 changeReferenceKind((byte)(refKind + (REF_putStatic - REF_getStatic)), refKind); 624 } 625 } 626 public boolean isGetter() { 627 return MethodHandleNatives.refKindIsGetter(getReferenceKind()); 628 } 629 public boolean isSetter() { 630 return MethodHandleNatives.refKindIsSetter(getReferenceKind()); 631 } 632 public MemberName asSetter() { 633 byte refKind = getReferenceKind(); 634 assert(MethodHandleNatives.refKindIsGetter(refKind)); 635 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField)); 636 byte setterRefKind = (byte)(refKind + (REF_putField - REF_getField)); 637 return clone().changeReferenceKind(setterRefKind, refKind); 638 } 639 /** Create a name for the given class. The resulting name will be in a resolved state. */ 640 public MemberName(Class<?> type) { 641 init(type.getDeclaringClass(), type.getSimpleName(), type, 642 flagsMods(IS_TYPE, type.getModifiers(), REF_NONE)); 643 initResolved(true); 644 } 645 646 /** 647 * Create a name for a signature-polymorphic invoker. 648 * This is a placeholder for a signature-polymorphic instance 649 * (of MH.invokeExact, etc.) that the JVM does not reify. 650 * See comments on {@link MethodHandleNatives#linkMethod}. 651 */ 652 static MemberName makeMethodHandleInvoke(String name, MethodType type) { 653 return makeMethodHandleInvoke(name, type, MH_INVOKE_MODS | SYNTHETIC); 654 } 655 static MemberName makeMethodHandleInvoke(String name, MethodType type, int mods) { 656 MemberName mem = new MemberName(MethodHandle.class, name, type, REF_invokeVirtual); 657 mem.flags |= mods; // it's not resolved, but add these modifiers anyway 658 assert(mem.isMethodHandleInvoke()) : mem; 659 return mem; 660 } 661 662 // bare-bones constructor; the JVM will fill it in 663 MemberName() { } 664 665 // locally useful cloner 666 @Override protected MemberName clone() { 667 try { 668 return (MemberName) super.clone(); 669 } catch (CloneNotSupportedException ex) { 670 throw newInternalError(ex); 671 } 672 } 673 674 /** Get the definition of this member name. 675 * This may be in a super-class of the declaring class of this member. 676 */ 677 public MemberName getDefinition() { 678 if (!isResolved()) throw new IllegalStateException("must be resolved: "+this); 679 if (isType()) return this; 680 MemberName res = this.clone(); 681 res.clazz = null; 682 res.type = null; 683 res.name = null; 684 res.resolution = res; 685 res.expandFromVM(); 686 assert(res.getName().equals(this.getName())); 687 return res; 688 } 689 690 @Override 691 public int hashCode() { 692 return Objects.hash(clazz, getReferenceKind(), name, getType()); 693 } 694 @Override 695 public boolean equals(Object that) { 696 return (that instanceof MemberName && this.equals((MemberName)that)); 697 } 698 699 /** Decide if two member names have exactly the same symbolic content. 700 * Does not take into account any actual class members, so even if 701 * two member names resolve to the same actual member, they may 702 * be distinct references. 703 */ 704 public boolean equals(MemberName that) { 705 if (this == that) return true; 706 if (that == null) return false; 707 return this.clazz == that.clazz 708 && this.getReferenceKind() == that.getReferenceKind() 709 && Objects.equals(this.name, that.name) 710 && Objects.equals(this.getType(), that.getType()); 711 } 712 713 // Construction from symbolic parts, for queries: 714 /** Create a field or type name from the given components: 715 * Declaring class, name, type, reference kind. 716 * The declaring class may be supplied as null if this is to be a bare name and type. 717 * The resulting name will in an unresolved state. 718 */ 719 public MemberName(Class<?> defClass, String name, Class<?> type, byte refKind) { 720 init(defClass, name, type, flagsMods(IS_FIELD, 0, refKind)); 721 initResolved(false); 722 } 723 /** Create a field or type name from the given components: Declaring class, name, type. 724 * The declaring class may be supplied as null if this is to be a bare name and type. 725 * The modifier flags default to zero. 726 * The resulting name will in an unresolved state. 727 */ 728 public MemberName(Class<?> defClass, String name, Class<?> type, Void unused) { 729 this(defClass, name, type, REF_NONE); 730 initResolved(false); 731 } 732 /** Create a method or constructor name from the given components: Declaring class, name, type, modifiers. 733 * It will be a constructor if and only if the name is {@code "<init>"}. 734 * The declaring class may be supplied as null if this is to be a bare name and type. 735 * The last argument is optional, a boolean which requests REF_invokeSpecial. 736 * The resulting name will in an unresolved state. 737 */ 738 public MemberName(Class<?> defClass, String name, MethodType type, byte refKind) { 739 int initFlags = (name != null && name.equals(CONSTRUCTOR_NAME) ? IS_CONSTRUCTOR : IS_METHOD); 740 init(defClass, name, type, flagsMods(initFlags, 0, refKind)); 741 initResolved(false); 742 } 743 /** Create a method, constructor, or field name from the given components: 744 * Reference kind, declaring class, name, type. 745 */ 746 public MemberName(byte refKind, Class<?> defClass, String name, Object type) { 747 int kindFlags; 748 if (MethodHandleNatives.refKindIsField(refKind)) { 749 kindFlags = IS_FIELD; 750 if (!(type instanceof Class)) 751 throw newIllegalArgumentException("not a field type"); 752 } else if (MethodHandleNatives.refKindIsMethod(refKind)) { 753 kindFlags = IS_METHOD; 754 if (!(type instanceof MethodType)) 755 throw newIllegalArgumentException("not a method type"); 756 } else if (refKind == REF_newInvokeSpecial) { 757 kindFlags = IS_CONSTRUCTOR; 758 if (!(type instanceof MethodType) || 759 !CONSTRUCTOR_NAME.equals(name)) 760 throw newIllegalArgumentException("not a constructor type or name"); 761 } else { 762 throw newIllegalArgumentException("bad reference kind "+refKind); 763 } 764 init(defClass, name, type, flagsMods(kindFlags, 0, refKind)); 765 initResolved(false); 766 } 767 /** Query whether this member name is resolved to a non-static, non-final method. 768 */ 769 public boolean hasReceiverTypeDispatch() { 770 return MethodHandleNatives.refKindDoesDispatch(getReferenceKind()); 771 } 772 773 /** Query whether this member name is resolved. 774 * A resolved member name is one for which the JVM has found 775 * a method, constructor, field, or type binding corresponding exactly to the name. 776 * (Document?) 777 */ 778 public boolean isResolved() { 779 return resolution == null; 780 } 781 782 private void initResolved(boolean isResolved) { 783 assert(this.resolution == null); // not initialized yet! 784 if (!isResolved) 785 this.resolution = this; 786 assert(isResolved() == isResolved); 787 } 788 789 void checkForTypeAlias() { 790 if (isInvocable()) { 791 MethodType type; 792 if (this.type instanceof MethodType) 793 type = (MethodType) this.type; 794 else 795 this.type = type = getMethodType(); 796 if (type.erase() == type) return; 797 if (VerifyAccess.isTypeVisible(type, clazz)) return; 798 throw new LinkageError("bad method type alias: "+type+" not visible from "+clazz); 799 } else { 800 Class<?> type; 801 if (this.type instanceof Class<?>) 802 type = (Class<?>) this.type; 803 else 804 this.type = type = getFieldType(); 805 if (VerifyAccess.isTypeVisible(type, clazz)) return; 806 throw new LinkageError("bad field type alias: "+type+" not visible from "+clazz); 807 } 808 } 809 810 811 /** Produce a string form of this member name. 812 * For types, it is simply the type's own string (as reported by {@code toString}). 813 * For fields, it is {@code "DeclaringClass.name/type"}. 814 * For methods and constructors, it is {@code "DeclaringClass.name(ptype...)rtype"}. 815 * If the declaring class is null, the prefix {@code "DeclaringClass."} is omitted. 816 * If the member is unresolved, a prefix {@code "*."} is prepended. 817 */ 818 @SuppressWarnings("LocalVariableHidesMemberVariable") 819 @Override 820 public String toString() { 821 if (isType()) 822 return type.toString(); // class java.lang.String 823 // else it is a field, method, or constructor 824 StringBuilder buf = new StringBuilder(); 825 if (getDeclaringClass() != null) { 826 buf.append(getName(clazz)); 827 buf.append('.'); 828 } 829 String name = getName(); 830 buf.append(name == null ? "*" : name); 831 Object type = getType(); 832 if (!isInvocable()) { 833 buf.append('/'); 834 buf.append(type == null ? "*" : getName(type)); 835 } else { 836 buf.append(type == null ? "(*)*" : getName(type)); 837 } 838 byte refKind = getReferenceKind(); 839 if (refKind != REF_NONE) { 840 buf.append('/'); 841 buf.append(MethodHandleNatives.refKindName(refKind)); 842 } 843 //buf.append("#").append(System.identityHashCode(this)); 844 return buf.toString(); 845 } 846 private static String getName(Object obj) { 847 if (obj instanceof Class<?>) 848 return ((Class<?>)obj).getName(); 849 return String.valueOf(obj); 850 } 851 852 public IllegalAccessException makeAccessException(String message, Object from) { 853 message = message + ": "+ toString(); 854 if (from != null) message += ", from " + from; 855 return new IllegalAccessException(message); 856 } 857 private String message() { 858 if (isResolved()) 859 return "no access"; 860 else if (isConstructor()) 861 return "no such constructor"; 862 else if (isMethod()) 863 return "no such method"; 864 else 865 return "no such field"; 866 } 867 public ReflectiveOperationException makeAccessException() { 868 String message = message() + ": "+ toString(); 869 ReflectiveOperationException ex; 870 if (isResolved() || !(resolution instanceof NoSuchMethodError || 871 resolution instanceof NoSuchFieldError)) 872 ex = new IllegalAccessException(message); 873 else if (isConstructor()) 874 ex = new NoSuchMethodException(message); 875 else if (isMethod()) 876 ex = new NoSuchMethodException(message); 877 else 878 ex = new NoSuchFieldException(message); 879 if (resolution instanceof Throwable) 880 ex.initCause((Throwable) resolution); 881 return ex; 882 } 883 884 /** Actually making a query requires an access check. */ 885 /*non-public*/ static Factory getFactory() { 886 return Factory.INSTANCE; 887 } 888 /** A factory type for resolving member names with the help of the VM. 889 * TBD: Define access-safe public constructors for this factory. 890 */ 891 /*non-public*/ static class Factory { 892 private Factory() { } // singleton pattern 893 static Factory INSTANCE = new Factory(); 894 895 private static int ALLOWED_FLAGS = ALL_KINDS; 896 897 /// Queries 898 List<MemberName> getMembers(Class<?> defc, 899 String matchName, Object matchType, 900 int matchFlags, Class<?> lookupClass) { 901 matchFlags &= ALLOWED_FLAGS; 902 String matchSig = null; 903 if (matchType != null) { 904 matchSig = BytecodeDescriptor.unparse(matchType); 905 if (matchSig.startsWith("(")) 906 matchFlags &= ~(ALL_KINDS & ~IS_INVOCABLE); 907 else 908 matchFlags &= ~(ALL_KINDS & ~IS_FIELD); 909 } 910 final int BUF_MAX = 0x2000; 911 int len1 = matchName == null ? 10 : matchType == null ? 4 : 1; 912 MemberName[] buf = newMemberBuffer(len1); 913 int totalCount = 0; 914 ArrayList<MemberName[]> bufs = null; 915 int bufCount = 0; 916 for (;;) { 917 bufCount = MethodHandleNatives.getMembers(defc, 918 matchName, matchSig, matchFlags, 919 lookupClass, 920 totalCount, buf); 921 if (bufCount <= buf.length) { 922 if (bufCount < 0) bufCount = 0; 923 totalCount += bufCount; 924 break; 925 } 926 // JVM returned to us with an intentional overflow! 927 totalCount += buf.length; 928 int excess = bufCount - buf.length; 929 if (bufs == null) bufs = new ArrayList<>(1); 930 bufs.add(buf); 931 int len2 = buf.length; 932 len2 = Math.max(len2, excess); 933 len2 = Math.max(len2, totalCount / 4); 934 buf = newMemberBuffer(Math.min(BUF_MAX, len2)); 935 } 936 ArrayList<MemberName> result = new ArrayList<>(totalCount); 937 if (bufs != null) { 938 for (MemberName[] buf0 : bufs) { 939 Collections.addAll(result, buf0); 940 } 941 } 942 result.addAll(Arrays.asList(buf).subList(0, bufCount)); 943 // Signature matching is not the same as type matching, since 944 // one signature might correspond to several types. 945 // So if matchType is a Class or MethodType, refilter the results. 946 if (matchType != null && matchType != matchSig) { 947 for (Iterator<MemberName> it = result.iterator(); it.hasNext();) { 948 MemberName m = it.next(); 949 if (!matchType.equals(m.getType())) 950 it.remove(); 951 } 952 } 953 return result; 954 } 955 /** Produce a resolved version of the given member. 956 * Super types are searched (for inherited members) if {@code searchSupers} is true. 957 * Access checking is performed on behalf of the given {@code lookupClass}. 958 * If lookup fails or access is not permitted, null is returned. 959 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in. 960 */ 961 private MemberName resolve(byte refKind, MemberName ref, Class<?> lookupClass) { 962 MemberName m = ref.clone(); // JVM will side-effect the ref 963 assert(refKind == m.getReferenceKind()); 964 try { 965 m = MethodHandleNatives.resolve(m, lookupClass); 966 m.checkForTypeAlias(); 967 m.resolution = null; 968 } catch (LinkageError ex) { 969 // JVM reports that the "bytecode behavior" would get an error 970 assert(!m.isResolved()); 971 m.resolution = ex; 972 return m; 973 } 974 assert(m.referenceKindIsConsistent()); 975 m.initResolved(true); 976 assert(m.vminfoIsConsistent()); 977 return m; 978 } 979 /** Produce a resolved version of the given member. 980 * Super types are searched (for inherited members) if {@code searchSupers} is true. 981 * Access checking is performed on behalf of the given {@code lookupClass}. 982 * If lookup fails or access is not permitted, a {@linkplain ReflectiveOperationException} is thrown. 983 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in. 984 */ 985 public 986 <NoSuchMemberException extends ReflectiveOperationException> 987 MemberName resolveOrFail(byte refKind, MemberName m, Class<?> lookupClass, 988 Class<NoSuchMemberException> nsmClass) 989 throws IllegalAccessException, NoSuchMemberException { 990 MemberName result = resolve(refKind, m, lookupClass); 991 if (result.isResolved()) 992 return result; 993 ReflectiveOperationException ex = result.makeAccessException(); 994 if (ex instanceof IllegalAccessException) throw (IllegalAccessException) ex; 995 throw nsmClass.cast(ex); 996 } 997 /** Produce a resolved version of the given member. 998 * Super types are searched (for inherited members) if {@code searchSupers} is true. 999 * Access checking is performed on behalf of the given {@code lookupClass}. 1000 * If lookup fails or access is not permitted, return null. 1001 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in. 1002 */ 1003 public 1004 MemberName resolveOrNull(byte refKind, MemberName m, Class<?> lookupClass) { 1005 MemberName result = resolve(refKind, m, lookupClass); 1006 if (result.isResolved()) 1007 return result; 1008 return null; 1009 } 1010 /** Return a list of all methods defined by the given class. 1011 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1012 * Access checking is performed on behalf of the given {@code lookupClass}. 1013 * Inaccessible members are not added to the last. 1014 */ 1015 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers, 1016 Class<?> lookupClass) { 1017 return getMethods(defc, searchSupers, null, null, lookupClass); 1018 } 1019 /** Return a list of matching methods defined by the given class. 1020 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1021 * Returned methods will match the name (if not null) and the type (if not null). 1022 * Access checking is performed on behalf of the given {@code lookupClass}. 1023 * Inaccessible members are not added to the last. 1024 */ 1025 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers, 1026 String name, MethodType type, Class<?> lookupClass) { 1027 int matchFlags = IS_METHOD | (searchSupers ? SEARCH_ALL_SUPERS : 0); 1028 return getMembers(defc, name, type, matchFlags, lookupClass); 1029 } 1030 /** Return a list of all constructors defined by the given class. 1031 * Access checking is performed on behalf of the given {@code lookupClass}. 1032 * Inaccessible members are not added to the last. 1033 */ 1034 public List<MemberName> getConstructors(Class<?> defc, Class<?> lookupClass) { 1035 return getMembers(defc, null, null, IS_CONSTRUCTOR, lookupClass); 1036 } 1037 /** Return a list of all fields defined by the given class. 1038 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1039 * Access checking is performed on behalf of the given {@code lookupClass}. 1040 * Inaccessible members are not added to the last. 1041 */ 1042 public List<MemberName> getFields(Class<?> defc, boolean searchSupers, 1043 Class<?> lookupClass) { 1044 return getFields(defc, searchSupers, null, null, lookupClass); 1045 } 1046 /** Return a list of all fields defined by the given class. 1047 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1048 * Returned fields will match the name (if not null) and the type (if not null). 1049 * Access checking is performed on behalf of the given {@code lookupClass}. 1050 * Inaccessible members are not added to the last. 1051 */ 1052 public List<MemberName> getFields(Class<?> defc, boolean searchSupers, 1053 String name, Class<?> type, Class<?> lookupClass) { 1054 int matchFlags = IS_FIELD | (searchSupers ? SEARCH_ALL_SUPERS : 0); 1055 return getMembers(defc, name, type, matchFlags, lookupClass); 1056 } 1057 /** Return a list of all nested types defined by the given class. 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 * Inaccessible members are not added to the last. 1061 */ 1062 public List<MemberName> getNestedTypes(Class<?> defc, boolean searchSupers, 1063 Class<?> lookupClass) { 1064 int matchFlags = IS_TYPE | (searchSupers ? SEARCH_ALL_SUPERS : 0); 1065 return getMembers(defc, null, null, matchFlags, lookupClass); 1066 } 1067 private static MemberName[] newMemberBuffer(int length) { 1068 MemberName[] buf = new MemberName[length]; 1069 // fill the buffer with dummy structs for the JVM to fill in 1070 for (int i = 0; i < length; i++) 1071 buf[i] = new MemberName(); 1072 return buf; 1073 } 1074 } 1075 1076 // static { 1077 // System.out.println("Hello world! My methods are:"); 1078 // System.out.println(Factory.INSTANCE.getMethods(MemberName.class, true, null)); 1079 // } 1080 }