1/* 2 * Copyright (c) 2008, 2017, 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 26package java.lang.invoke; 27 28import sun.invoke.util.BytecodeDescriptor; 29import sun.invoke.util.VerifyAccess; 30 31import java.lang.reflect.Constructor; 32import java.lang.reflect.Field; 33import java.lang.reflect.Member; 34import java.lang.reflect.Method; 35import java.lang.reflect.Modifier; 36import java.util.ArrayList; 37import java.util.Collections; 38import java.util.Iterator; 39import java.util.List; 40import java.util.Objects; 41 42import static java.lang.invoke.MethodHandleNatives.Constants.*; 43import static java.lang.invoke.MethodHandleStatics.newIllegalArgumentException; 44import static java.lang.invoke.MethodHandleStatics.newInternalError; 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 member has been determined by the JVM. 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 ResolvedMethodName { 74 //@Injected JVM_Method* vmtarget; 75 //@Injected Class<?> vmholder; 76}; 77 78/*non-public*/ final class MemberName implements Member, Cloneable { 79 private Class<?> clazz; // class in which the member is defined 80 private String name; // may be null if not yet materialized 81 private Object type; // may be null if not yet materialized 82 private int flags; // modifier bits; see reflect.Modifier 83 private ResolvedMethodName method; // cached resolved method information 84 //@Injected intptr_t vmindex; // vtable index or offset of resolved member 85 Object resolution; // if null, this guy is resolved 86 87 /** Return the declaring class of this member. 88 * In the case of a bare name and type, the declaring class will be null. 89 */ 90 public Class<?> getDeclaringClass() { 91 return clazz; 92 } 93 94 /** Utility method producing the class loader of the declaring class. */ 95 public ClassLoader getClassLoader() { 96 return clazz.getClassLoader(); 97 } 98 99 /** Return the simple name of this member. 100 * For a type, it is the same as {@link Class#getSimpleName}. 101 * For a method or field, it is the simple name of the member. 102 * For a constructor, it is always {@code "<init>"}. 103 */ 104 public String getName() { 105 if (name == null) { 106 expandFromVM(); 107 if (name == null) { 108 return null; 109 } 110 } 111 return name; 112 } 113 114 public MethodType getMethodOrFieldType() { 115 if (isInvocable()) 116 return getMethodType(); 117 if (isGetter()) 118 return MethodType.methodType(getFieldType()); 119 if (isSetter()) 120 return MethodType.methodType(void.class, getFieldType()); 121 throw new InternalError("not a method or field: "+this); 122 } 123 124 /** Return the declared type of this member, which 125 * must be a method or constructor. 126 */ 127 public MethodType getMethodType() { 128 if (type == null) { 129 expandFromVM(); 130 if (type == null) { 131 return null; 132 } 133 } 134 if (!isInvocable()) { 135 throw newIllegalArgumentException("not invocable, no method type"); 136 } 137 138 { 139 // Get a snapshot of type which doesn't get changed by racing threads. 140 final Object type = this.type; 141 if (type instanceof MethodType) { 142 return (MethodType) type; 143 } 144 } 145 146 // type is not a MethodType yet. Convert it thread-safely. 147 synchronized (this) { 148 if (type instanceof String) { 149 String sig = (String) type; 150 MethodType res = MethodType.fromDescriptor(sig, getClassLoader()); 151 type = res; 152 } else if (type instanceof Object[]) { 153 Object[] typeInfo = (Object[]) type; 154 Class<?>[] ptypes = (Class<?>[]) typeInfo[1]; 155 Class<?> rtype = (Class<?>) typeInfo[0]; 156 MethodType res = MethodType.makeImpl(rtype, ptypes, true); 157 type = res; 158 } 159 // Make sure type is a MethodType for racing threads. 160 assert type instanceof MethodType : "bad method type " + type; 161 } 162 return (MethodType) type; 163 } 164 165 /** Return the actual type under which this method or constructor must be invoked. 166 * For non-static methods or constructors, this is the type with a leading parameter, 167 * a reference to declaring class. For static methods, it is the same as the declared type. 168 */ 169 public MethodType getInvocationType() { 170 MethodType itype = getMethodOrFieldType(); 171 if (isConstructor() && getReferenceKind() == REF_newInvokeSpecial) 172 return itype.changeReturnType(clazz); 173 if (!isStatic()) 174 return itype.insertParameterTypes(0, clazz); 175 return itype; 176 } 177 178 /** Utility method producing the parameter types of the method type. */ 179 public Class<?>[] getParameterTypes() { 180 return getMethodType().parameterArray(); 181 } 182 183 /** Utility method producing the return type of the method type. */ 184 public Class<?> getReturnType() { 185 return getMethodType().returnType(); 186 } 187 188 /** Return the declared type of this member, which 189 * must be a field or type. 190 * If it is a type member, that type itself is returned. 191 */ 192 public Class<?> getFieldType() { 193 if (type == null) { 194 expandFromVM(); 195 if (type == null) { 196 return null; 197 } 198 } 199 if (isInvocable()) { 200 throw newIllegalArgumentException("not a field or nested class, no simple type"); 201 } 202 203 { 204 // Get a snapshot of type which doesn't get changed by racing threads. 205 final Object type = this.type; 206 if (type instanceof Class<?>) { 207 return (Class<?>) type; 208 } 209 } 210 211 // type is not a Class yet. Convert it thread-safely. 212 synchronized (this) { 213 if (type instanceof String) { 214 String sig = (String) type; 215 MethodType mtype = MethodType.fromDescriptor("()"+sig, getClassLoader()); 216 Class<?> res = mtype.returnType(); 217 type = res; 218 } 219 // Make sure type is a Class for racing threads. 220 assert type instanceof Class<?> : "bad field type " + type; 221 } 222 return (Class<?>) type; 223 } 224 225 /** Utility method to produce either the method type or field type of this member. */ 226 public Object getType() { 227 return (isInvocable() ? getMethodType() : getFieldType()); 228 } 229 230 /** Utility method to produce the signature of this member, 231 * used within the class file format to describe its type. 232 */ 233 public String getSignature() { 234 if (type == null) { 235 expandFromVM(); 236 if (type == null) { 237 return null; 238 } 239 } 240 if (isInvocable()) 241 return BytecodeDescriptor.unparse(getMethodType()); 242 else 243 return BytecodeDescriptor.unparse(getFieldType()); 244 } 245 246 /** Return the modifier flags of this member. 247 * @see java.lang.reflect.Modifier 248 */ 249 public int getModifiers() { 250 return (flags & RECOGNIZED_MODIFIERS); 251 } 252 253 /** Return the reference kind of this member, or zero if none. 254 */ 255 public byte getReferenceKind() { 256 return (byte) ((flags >>> MN_REFERENCE_KIND_SHIFT) & MN_REFERENCE_KIND_MASK); 257 } 258 private boolean referenceKindIsConsistent() { 259 byte refKind = getReferenceKind(); 260 if (refKind == REF_NONE) return isType(); 261 if (isField()) { 262 assert(staticIsConsistent()); 263 assert(MethodHandleNatives.refKindIsField(refKind)); 264 } else if (isConstructor()) { 265 assert(refKind == REF_newInvokeSpecial || refKind == REF_invokeSpecial); 266 } else if (isMethod()) { 267 assert(staticIsConsistent()); 268 assert(MethodHandleNatives.refKindIsMethod(refKind)); 269 if (clazz.isInterface()) 270 assert(refKind == REF_invokeInterface || 271 refKind == REF_invokeStatic || 272 refKind == REF_invokeSpecial || 273 refKind == REF_invokeVirtual && isObjectPublicMethod()); 274 } else { 275 assert(false); 276 } 277 return true; 278 } 279 private boolean isObjectPublicMethod() { 280 if (clazz == Object.class) return true; 281 MethodType mtype = getMethodType(); 282 if (name.equals("toString") && mtype.returnType() == String.class && mtype.parameterCount() == 0) 283 return true; 284 if (name.equals("hashCode") && mtype.returnType() == int.class && mtype.parameterCount() == 0) 285 return true; 286 if (name.equals("equals") && mtype.returnType() == boolean.class && mtype.parameterCount() == 1 && mtype.parameterType(0) == Object.class) 287 return true; 288 return false; 289 } 290 /*non-public*/ boolean referenceKindIsConsistentWith(int originalRefKind) { 291 int refKind = getReferenceKind(); 292 if (refKind == originalRefKind) return true; 293 switch (originalRefKind) { 294 case REF_invokeInterface: 295 // Looking up an interface method, can get (e.g.) Object.hashCode 296 assert(refKind == REF_invokeVirtual || 297 refKind == REF_invokeSpecial) : this; 298 return true; 299 case REF_invokeVirtual: 300 case REF_newInvokeSpecial: 301 // Looked up a virtual, can get (e.g.) final String.hashCode. 302 assert(refKind == REF_invokeSpecial) : this; 303 return true; 304 } 305 assert(false) : this+" != "+MethodHandleNatives.refKindName((byte)originalRefKind); 306 return true; 307 } 308 private boolean staticIsConsistent() { 309 byte refKind = getReferenceKind(); 310 return MethodHandleNatives.refKindIsStatic(refKind) == isStatic() || getModifiers() == 0; 311 } 312 private boolean vminfoIsConsistent() { 313 byte refKind = getReferenceKind(); 314 assert(isResolved()); // else don't call 315 Object vminfo = MethodHandleNatives.getMemberVMInfo(this); 316 assert(vminfo instanceof Object[]); 317 long vmindex = (Long) ((Object[])vminfo)[0]; 318 Object vmtarget = ((Object[])vminfo)[1]; 319 if (MethodHandleNatives.refKindIsField(refKind)) { 320 assert(vmindex >= 0) : vmindex + ":" + this; 321 assert(vmtarget instanceof Class); 322 } else { 323 if (MethodHandleNatives.refKindDoesDispatch(refKind)) 324 assert(vmindex >= 0) : vmindex + ":" + this; 325 else 326 assert(vmindex < 0) : vmindex; 327 assert(vmtarget instanceof MemberName) : vmtarget + " in " + this; 328 } 329 return true; 330 } 331 332 private MemberName changeReferenceKind(byte refKind, byte oldKind) { 333 assert(getReferenceKind() == oldKind); 334 assert(MethodHandleNatives.refKindIsValid(refKind)); 335 flags += (((int)refKind - oldKind) << MN_REFERENCE_KIND_SHIFT); 336 return this; 337 } 338 339 private boolean testFlags(int mask, int value) { 340 return (flags & mask) == value; 341 } 342 private boolean testAllFlags(int mask) { 343 return testFlags(mask, mask); 344 } 345 private boolean testAnyFlags(int mask) { 346 return !testFlags(mask, 0); 347 } 348 349 /** Utility method to query if this member is a method handle invocation (invoke or invokeExact). 350 */ 351 public boolean isMethodHandleInvoke() { 352 final int bits = MH_INVOKE_MODS &~ Modifier.PUBLIC; 353 final int negs = Modifier.STATIC; 354 if (testFlags(bits | negs, bits) && 355 clazz == MethodHandle.class) { 356 return isMethodHandleInvokeName(name); 357 } 358 return false; 359 } 360 public static boolean isMethodHandleInvokeName(String name) { 361 switch (name) { 362 case "invoke": 363 case "invokeExact": 364 return true; 365 default: 366 return false; 367 } 368 } 369 public boolean isVarHandleMethodInvoke() { 370 final int bits = MH_INVOKE_MODS &~ Modifier.PUBLIC; 371 final int negs = Modifier.STATIC; 372 if (testFlags(bits | negs, bits) && 373 clazz == VarHandle.class) { 374 return isVarHandleMethodInvokeName(name); 375 } 376 return false; 377 } 378 public static boolean isVarHandleMethodInvokeName(String name) { 379 try { 380 VarHandle.AccessMode.valueFromMethodName(name); 381 return true; 382 } catch (IllegalArgumentException e) { 383 return false; 384 } 385 } 386 private static final int MH_INVOKE_MODS = Modifier.NATIVE | Modifier.FINAL | Modifier.PUBLIC; 387 388 /** Utility method to query the modifier flags of this member. */ 389 public boolean isStatic() { 390 return Modifier.isStatic(flags); 391 } 392 /** Utility method to query the modifier flags of this member. */ 393 public boolean isPublic() { 394 return Modifier.isPublic(flags); 395 } 396 /** Utility method to query the modifier flags of this member. */ 397 public boolean isPrivate() { 398 return Modifier.isPrivate(flags); 399 } 400 /** Utility method to query the modifier flags of this member. */ 401 public boolean isProtected() { 402 return Modifier.isProtected(flags); 403 } 404 /** Utility method to query the modifier flags of this member. */ 405 public boolean isFinal() { 406 return Modifier.isFinal(flags); 407 } 408 /** Utility method to query whether this member or its defining class is final. */ 409 public boolean canBeStaticallyBound() { 410 return Modifier.isFinal(flags | clazz.getModifiers()); 411 } 412 /** Utility method to query the modifier flags of this member. */ 413 public boolean isVolatile() { 414 return Modifier.isVolatile(flags); 415 } 416 /** Utility method to query the modifier flags of this member. */ 417 public boolean isAbstract() { 418 return Modifier.isAbstract(flags); 419 } 420 /** Utility method to query the modifier flags of this member. */ 421 public boolean isNative() { 422 return Modifier.isNative(flags); 423 } 424 // let the rest (native, volatile, transient, etc.) be tested via Modifier.isFoo 425 426 // unofficial modifier flags, used by HotSpot: 427 static final int BRIDGE = 0x00000040; 428 static final int VARARGS = 0x00000080; 429 static final int SYNTHETIC = 0x00001000; 430 static final int ANNOTATION= 0x00002000; 431 static final int ENUM = 0x00004000; 432 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */ 433 public boolean isBridge() { 434 return testAllFlags(IS_METHOD | BRIDGE); 435 } 436 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */ 437 public boolean isVarargs() { 438 return testAllFlags(VARARGS) && isInvocable(); 439 } 440 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */ 441 public boolean isSynthetic() { 442 return testAllFlags(SYNTHETIC); 443 } 444 445 static final String CONSTRUCTOR_NAME = "<init>"; // the ever-popular 446 447 // modifiers exported by the JVM: 448 static final int RECOGNIZED_MODIFIERS = 0xFFFF; 449 450 // private flags, not part of RECOGNIZED_MODIFIERS: 451 static final int 452 IS_METHOD = MN_IS_METHOD, // method (not constructor) 453 IS_CONSTRUCTOR = MN_IS_CONSTRUCTOR, // constructor 454 IS_FIELD = MN_IS_FIELD, // field 455 IS_TYPE = MN_IS_TYPE, // nested type 456 CALLER_SENSITIVE = MN_CALLER_SENSITIVE; // @CallerSensitive annotation detected 457 458 static final int ALL_ACCESS = Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED; 459 static final int ALL_KINDS = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE; 460 static final int IS_INVOCABLE = IS_METHOD | IS_CONSTRUCTOR; 461 static final int IS_FIELD_OR_METHOD = IS_METHOD | IS_FIELD; 462 static final int SEARCH_ALL_SUPERS = MN_SEARCH_SUPERCLASSES | MN_SEARCH_INTERFACES; 463 464 /** Utility method to query whether this member is a method or constructor. */ 465 public boolean isInvocable() { 466 return testAnyFlags(IS_INVOCABLE); 467 } 468 /** Utility method to query whether this member is a method, constructor, or field. */ 469 public boolean isFieldOrMethod() { 470 return testAnyFlags(IS_FIELD_OR_METHOD); 471 } 472 /** Query whether this member is a method. */ 473 public boolean isMethod() { 474 return testAllFlags(IS_METHOD); 475 } 476 /** Query whether this member is a constructor. */ 477 public boolean isConstructor() { 478 return testAllFlags(IS_CONSTRUCTOR); 479 } 480 /** Query whether this member is a field. */ 481 public boolean isField() { 482 return testAllFlags(IS_FIELD); 483 } 484 /** Query whether this member is a type. */ 485 public boolean isType() { 486 return testAllFlags(IS_TYPE); 487 } 488 /** Utility method to query whether this member is neither public, private, nor protected. */ 489 public boolean isPackage() { 490 return !testAnyFlags(ALL_ACCESS); 491 } 492 /** Query whether this member has a CallerSensitive annotation. */ 493 public boolean isCallerSensitive() { 494 return testAllFlags(CALLER_SENSITIVE); 495 } 496 497 /** Utility method to query whether this member is accessible from a given lookup class. */ 498 public boolean isAccessibleFrom(Class<?> lookupClass) { 499 int mode = (ALL_ACCESS|MethodHandles.Lookup.PACKAGE|MethodHandles.Lookup.MODULE); 500 return VerifyAccess.isMemberAccessible(this.getDeclaringClass(), this.getDeclaringClass(), flags, 501 lookupClass, mode); 502 } 503 504 /** 505 * Check if MemberName is a call to a method named {@code name} in class {@code declaredClass}. 506 */ 507 public boolean refersTo(Class<?> declc, String n) { 508 return clazz == declc && getName().equals(n); 509 } 510 511 /** Initialize a query. It is not resolved. */ 512 private void init(Class<?> defClass, String name, Object type, int flags) { 513 // defining class is allowed to be null (for a naked name/type pair) 514 //name.toString(); // null check 515 //type.equals(type); // null check 516 // fill in fields: 517 this.clazz = defClass; 518 this.name = name; 519 this.type = type; 520 this.flags = flags; 521 assert(testAnyFlags(ALL_KINDS)); 522 assert(this.resolution == null); // nobody should have touched this yet 523 //assert(referenceKindIsConsistent()); // do this after resolution 524 } 525 526 /** 527 * Calls down to the VM to fill in the fields. This method is 528 * synchronized to avoid racing calls. 529 */ 530 private void expandFromVM() { 531 if (type != null) { 532 return; 533 } 534 if (!isResolved()) { 535 return; 536 } 537 MethodHandleNatives.expand(this); 538 } 539 540 // Capturing information from the Core Reflection API: 541 private static int flagsMods(int flags, int mods, byte refKind) { 542 assert((flags & RECOGNIZED_MODIFIERS) == 0); 543 assert((mods & ~RECOGNIZED_MODIFIERS) == 0); 544 assert((refKind & ~MN_REFERENCE_KIND_MASK) == 0); 545 return flags | mods | (refKind << MN_REFERENCE_KIND_SHIFT); 546 } 547 /** Create a name for the given reflected method. The resulting name will be in a resolved state. */ 548 public MemberName(Method m) { 549 this(m, false); 550 } 551 @SuppressWarnings("LeakingThisInConstructor") 552 public MemberName(Method m, boolean wantSpecial) { 553 Objects.requireNonNull(m); 554 // fill in vmtarget, vmindex while we have m in hand: 555 MethodHandleNatives.init(this, m); 556 if (clazz == null) { // MHN.init failed 557 if (m.getDeclaringClass() == MethodHandle.class && 558 isMethodHandleInvokeName(m.getName())) { 559 // The JVM did not reify this signature-polymorphic instance. 560 // Need a special case here. 561 // See comments on MethodHandleNatives.linkMethod. 562 MethodType type = MethodType.methodType(m.getReturnType(), m.getParameterTypes()); 563 int flags = flagsMods(IS_METHOD, m.getModifiers(), REF_invokeVirtual); 564 init(MethodHandle.class, m.getName(), type, flags); 565 if (isMethodHandleInvoke()) 566 return; 567 } 568 if (m.getDeclaringClass() == VarHandle.class && 569 isVarHandleMethodInvokeName(m.getName())) { 570 // The JVM did not reify this signature-polymorphic instance. 571 // Need a special case here. 572 // See comments on MethodHandleNatives.linkMethod. 573 MethodType type = MethodType.methodType(m.getReturnType(), m.getParameterTypes()); 574 int flags = flagsMods(IS_METHOD, m.getModifiers(), REF_invokeVirtual); 575 init(VarHandle.class, m.getName(), type, flags); 576 if (isVarHandleMethodInvoke()) 577 return; 578 } 579 throw new LinkageError(m.toString()); 580 } 581 assert(isResolved() && this.clazz != null); 582 this.name = m.getName(); 583 if (this.type == null) 584 this.type = new Object[] { m.getReturnType(), m.getParameterTypes() }; 585 if (wantSpecial) { 586 if (isAbstract()) 587 throw new AbstractMethodError(this.toString()); 588 if (getReferenceKind() == REF_invokeVirtual) 589 changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual); 590 else if (getReferenceKind() == REF_invokeInterface) 591 // invokeSpecial on a default method 592 changeReferenceKind(REF_invokeSpecial, REF_invokeInterface); 593 } 594 } 595 public MemberName asSpecial() { 596 switch (getReferenceKind()) { 597 case REF_invokeSpecial: return this; 598 case REF_invokeVirtual: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual); 599 case REF_invokeInterface: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeInterface); 600 case REF_newInvokeSpecial: return clone().changeReferenceKind(REF_invokeSpecial, REF_newInvokeSpecial); 601 } 602 throw new IllegalArgumentException(this.toString()); 603 } 604 /** If this MN is not REF_newInvokeSpecial, return a clone with that ref. kind. 605 * In that case it must already be REF_invokeSpecial. 606 */ 607 public MemberName asConstructor() { 608 switch (getReferenceKind()) { 609 case REF_invokeSpecial: return clone().changeReferenceKind(REF_newInvokeSpecial, REF_invokeSpecial); 610 case REF_newInvokeSpecial: return this; 611 } 612 throw new IllegalArgumentException(this.toString()); 613 } 614 /** If this MN is a REF_invokeSpecial, return a clone with the "normal" kind 615 * REF_invokeVirtual; also switch either to REF_invokeInterface if clazz.isInterface. 616 * The end result is to get a fully virtualized version of the MN. 617 * (Note that resolving in the JVM will sometimes devirtualize, changing 618 * REF_invokeVirtual of a final to REF_invokeSpecial, and REF_invokeInterface 619 * in some corner cases to either of the previous two; this transform 620 * undoes that change under the assumption that it occurred.) 621 */ 622 public MemberName asNormalOriginal() { 623 byte normalVirtual = clazz.isInterface() ? REF_invokeInterface : REF_invokeVirtual; 624 byte refKind = getReferenceKind(); 625 byte newRefKind = refKind; 626 MemberName result = this; 627 switch (refKind) { 628 case REF_invokeInterface: 629 case REF_invokeVirtual: 630 case REF_invokeSpecial: 631 newRefKind = normalVirtual; 632 break; 633 } 634 if (newRefKind == refKind) 635 return this; 636 result = clone().changeReferenceKind(newRefKind, refKind); 637 assert(this.referenceKindIsConsistentWith(result.getReferenceKind())); 638 return result; 639 } 640 /** Create a name for the given reflected constructor. The resulting name will be in a resolved state. */ 641 @SuppressWarnings("LeakingThisInConstructor") 642 public MemberName(Constructor<?> ctor) { 643 Objects.requireNonNull(ctor); 644 // fill in vmtarget, vmindex while we have ctor in hand: 645 MethodHandleNatives.init(this, ctor); 646 assert(isResolved() && this.clazz != null); 647 this.name = CONSTRUCTOR_NAME; 648 if (this.type == null) 649 this.type = new Object[] { void.class, ctor.getParameterTypes() }; 650 } 651 /** Create a name for the given reflected field. The resulting name will be in a resolved state. 652 */ 653 public MemberName(Field fld) { 654 this(fld, false); 655 } 656 @SuppressWarnings("LeakingThisInConstructor") 657 public MemberName(Field fld, boolean makeSetter) { 658 Objects.requireNonNull(fld); 659 // fill in vmtarget, vmindex while we have fld in hand: 660 MethodHandleNatives.init(this, fld); 661 assert(isResolved() && this.clazz != null); 662 this.name = fld.getName(); 663 this.type = fld.getType(); 664 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField)); 665 byte refKind = this.getReferenceKind(); 666 assert(refKind == (isStatic() ? REF_getStatic : REF_getField)); 667 if (makeSetter) { 668 changeReferenceKind((byte)(refKind + (REF_putStatic - REF_getStatic)), refKind); 669 } 670 } 671 public boolean isGetter() { 672 return MethodHandleNatives.refKindIsGetter(getReferenceKind()); 673 } 674 public boolean isSetter() { 675 return MethodHandleNatives.refKindIsSetter(getReferenceKind()); 676 } 677 public MemberName asSetter() { 678 byte refKind = getReferenceKind(); 679 assert(MethodHandleNatives.refKindIsGetter(refKind)); 680 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField)); 681 byte setterRefKind = (byte)(refKind + (REF_putField - REF_getField)); 682 return clone().changeReferenceKind(setterRefKind, refKind); 683 } 684 /** Create a name for the given class. The resulting name will be in a resolved state. */ 685 public MemberName(Class<?> type) { 686 init(type.getDeclaringClass(), type.getSimpleName(), type, 687 flagsMods(IS_TYPE, type.getModifiers(), REF_NONE)); 688 initResolved(true); 689 } 690 691 /** 692 * Create a name for a signature-polymorphic invoker. 693 * This is a placeholder for a signature-polymorphic instance 694 * (of MH.invokeExact, etc.) that the JVM does not reify. 695 * See comments on {@link MethodHandleNatives#linkMethod}. 696 */ 697 static MemberName makeMethodHandleInvoke(String name, MethodType type) { 698 return makeMethodHandleInvoke(name, type, MH_INVOKE_MODS | SYNTHETIC); 699 } 700 static MemberName makeMethodHandleInvoke(String name, MethodType type, int mods) { 701 MemberName mem = new MemberName(MethodHandle.class, name, type, REF_invokeVirtual); 702 mem.flags |= mods; // it's not resolved, but add these modifiers anyway 703 assert(mem.isMethodHandleInvoke()) : mem; 704 return mem; 705 } 706 707 static MemberName makeVarHandleMethodInvoke(String name, MethodType type) { 708 return makeVarHandleMethodInvoke(name, type, MH_INVOKE_MODS | SYNTHETIC); 709 } 710 static MemberName makeVarHandleMethodInvoke(String name, MethodType type, int mods) { 711 MemberName mem = new MemberName(VarHandle.class, name, type, REF_invokeVirtual); 712 mem.flags |= mods; // it's not resolved, but add these modifiers anyway 713 assert(mem.isVarHandleMethodInvoke()) : mem; 714 return mem; 715 } 716 717 // bare-bones constructor; the JVM will fill it in 718 MemberName() { } 719 720 // locally useful cloner 721 @Override protected MemberName clone() { 722 try { 723 return (MemberName) super.clone(); 724 } catch (CloneNotSupportedException ex) { 725 throw newInternalError(ex); 726 } 727 } 728 729 /** Get the definition of this member name. 730 * This may be in a super-class of the declaring class of this member. 731 */ 732 public MemberName getDefinition() { 733 if (!isResolved()) throw new IllegalStateException("must be resolved: "+this); 734 if (isType()) return this; 735 MemberName res = this.clone(); 736 res.clazz = null; 737 res.type = null; 738 res.name = null; 739 res.resolution = res; 740 res.expandFromVM(); 741 assert(res.getName().equals(this.getName())); 742 return res; 743 } 744 745 @Override 746 @SuppressWarnings("deprecation") 747 public int hashCode() { 748 // Avoid autoboxing getReferenceKind(), since this is used early and will force 749 // early initialization of Byte$ByteCache 750 return Objects.hash(clazz, new Byte(getReferenceKind()), name, getType()); 751 } 752 753 @Override 754 public boolean equals(Object that) { 755 return (that instanceof MemberName && this.equals((MemberName)that)); 756 } 757 758 /** Decide if two member names have exactly the same symbolic content. 759 * Does not take into account any actual class members, so even if 760 * two member names resolve to the same actual member, they may 761 * be distinct references. 762 */ 763 public boolean equals(MemberName that) { 764 if (this == that) return true; 765 if (that == null) return false; 766 return this.clazz == that.clazz 767 && this.getReferenceKind() == that.getReferenceKind() 768 && Objects.equals(this.name, that.name) 769 && Objects.equals(this.getType(), that.getType()); 770 } 771 772 // Construction from symbolic parts, for queries: 773 /** Create a field or type name from the given components: 774 * Declaring class, name, type, reference kind. 775 * The declaring class may be supplied as null if this is to be a bare name and type. 776 * The resulting name will in an unresolved state. 777 */ 778 public MemberName(Class<?> defClass, String name, Class<?> type, byte refKind) { 779 init(defClass, name, type, flagsMods(IS_FIELD, 0, refKind)); 780 initResolved(false); 781 } 782 /** Create a method or constructor name from the given components: 783 * Declaring class, name, type, reference kind. 784 * It will be a constructor if and only if the name is {@code "<init>"}. 785 * The declaring class may be supplied as null if this is to be a bare name and type. 786 * The last argument is optional, a boolean which requests REF_invokeSpecial. 787 * The resulting name will in an unresolved state. 788 */ 789 public MemberName(Class<?> defClass, String name, MethodType type, byte refKind) { 790 int initFlags = (name != null && name.equals(CONSTRUCTOR_NAME) ? IS_CONSTRUCTOR : IS_METHOD); 791 init(defClass, name, type, flagsMods(initFlags, 0, refKind)); 792 initResolved(false); 793 } 794 /** Create a method, constructor, or field name from the given components: 795 * Reference kind, declaring class, name, type. 796 */ 797 public MemberName(byte refKind, Class<?> defClass, String name, Object type) { 798 int kindFlags; 799 if (MethodHandleNatives.refKindIsField(refKind)) { 800 kindFlags = IS_FIELD; 801 if (!(type instanceof Class)) 802 throw newIllegalArgumentException("not a field type"); 803 } else if (MethodHandleNatives.refKindIsMethod(refKind)) { 804 kindFlags = IS_METHOD; 805 if (!(type instanceof MethodType)) 806 throw newIllegalArgumentException("not a method type"); 807 } else if (refKind == REF_newInvokeSpecial) { 808 kindFlags = IS_CONSTRUCTOR; 809 if (!(type instanceof MethodType) || 810 !CONSTRUCTOR_NAME.equals(name)) 811 throw newIllegalArgumentException("not a constructor type or name"); 812 } else { 813 throw newIllegalArgumentException("bad reference kind "+refKind); 814 } 815 init(defClass, name, type, flagsMods(kindFlags, 0, refKind)); 816 initResolved(false); 817 } 818 /** Query whether this member name is resolved to a non-static, non-final method. 819 */ 820 public boolean hasReceiverTypeDispatch() { 821 return MethodHandleNatives.refKindDoesDispatch(getReferenceKind()); 822 } 823 824 /** Query whether this member name is resolved. 825 * A resolved member name is one for which the JVM has found 826 * a method, constructor, field, or type binding corresponding exactly to the name. 827 * (Document?) 828 */ 829 public boolean isResolved() { 830 return resolution == null; 831 } 832 833 void initResolved(boolean isResolved) { 834 assert(this.resolution == null); // not initialized yet! 835 if (!isResolved) 836 this.resolution = this; 837 assert(isResolved() == isResolved); 838 } 839 840 void checkForTypeAlias(Class<?> refc) { 841 if (isInvocable()) { 842 MethodType type; 843 if (this.type instanceof MethodType) 844 type = (MethodType) this.type; 845 else 846 this.type = type = getMethodType(); 847 if (type.erase() == type) return; 848 if (VerifyAccess.isTypeVisible(type, refc)) return; 849 throw new LinkageError("bad method type alias: "+type+" not visible from "+refc); 850 } else { 851 Class<?> type; 852 if (this.type instanceof Class<?>) 853 type = (Class<?>) this.type; 854 else 855 this.type = type = getFieldType(); 856 if (VerifyAccess.isTypeVisible(type, refc)) return; 857 throw new LinkageError("bad field type alias: "+type+" not visible from "+refc); 858 } 859 } 860 861 862 /** Produce a string form of this member name. 863 * For types, it is simply the type's own string (as reported by {@code toString}). 864 * For fields, it is {@code "DeclaringClass.name/type"}. 865 * For methods and constructors, it is {@code "DeclaringClass.name(ptype...)rtype"}. 866 * If the declaring class is null, the prefix {@code "DeclaringClass."} is omitted. 867 * If the member is unresolved, a prefix {@code "*."} is prepended. 868 */ 869 @SuppressWarnings("LocalVariableHidesMemberVariable") 870 @Override 871 public String toString() { 872 if (isType()) 873 return type.toString(); // class java.lang.String 874 // else it is a field, method, or constructor 875 StringBuilder buf = new StringBuilder(); 876 if (getDeclaringClass() != null) { 877 buf.append(getName(clazz)); 878 buf.append('.'); 879 } 880 String name = getName(); 881 buf.append(name == null ? "*" : name); 882 Object type = getType(); 883 if (!isInvocable()) { 884 buf.append('/'); 885 buf.append(type == null ? "*" : getName(type)); 886 } else { 887 buf.append(type == null ? "(*)*" : getName(type)); 888 } 889 byte refKind = getReferenceKind(); 890 if (refKind != REF_NONE) { 891 buf.append('/'); 892 buf.append(MethodHandleNatives.refKindName(refKind)); 893 } 894 //buf.append("#").append(System.identityHashCode(this)); 895 return buf.toString(); 896 } 897 private static String getName(Object obj) { 898 if (obj instanceof Class<?>) 899 return ((Class<?>)obj).getName(); 900 return String.valueOf(obj); 901 } 902 903 public IllegalAccessException makeAccessException(String message, Object from) { 904 message = message + ": "+ toString(); 905 if (from != null) { 906 if (from == MethodHandles.publicLookup()) { 907 message += ", from public Lookup"; 908 } else { 909 Module m; 910 if (from instanceof MethodHandles.Lookup) { 911 MethodHandles.Lookup lookup = (MethodHandles.Lookup)from; 912 m = lookup.lookupClass().getModule(); 913 } else { 914 m = from.getClass().getModule(); 915 } 916 message += ", from " + from + " (" + m + ")"; 917 } 918 } 919 return new IllegalAccessException(message); 920 } 921 private String message() { 922 if (isResolved()) 923 return "no access"; 924 else if (isConstructor()) 925 return "no such constructor"; 926 else if (isMethod()) 927 return "no such method"; 928 else 929 return "no such field"; 930 } 931 public ReflectiveOperationException makeAccessException() { 932 String message = message() + ": "+ toString(); 933 ReflectiveOperationException ex; 934 if (isResolved() || !(resolution instanceof NoSuchMethodError || 935 resolution instanceof NoSuchFieldError)) 936 ex = new IllegalAccessException(message); 937 else if (isConstructor()) 938 ex = new NoSuchMethodException(message); 939 else if (isMethod()) 940 ex = new NoSuchMethodException(message); 941 else 942 ex = new NoSuchFieldException(message); 943 if (resolution instanceof Throwable) 944 ex.initCause((Throwable) resolution); 945 return ex; 946 } 947 948 /** Actually making a query requires an access check. */ 949 /*non-public*/ static Factory getFactory() { 950 return Factory.INSTANCE; 951 } 952 /** A factory type for resolving member names with the help of the VM. 953 * TBD: Define access-safe public constructors for this factory. 954 */ 955 /*non-public*/ static class Factory { 956 private Factory() { } // singleton pattern 957 static Factory INSTANCE = new Factory(); 958 959 private static int ALLOWED_FLAGS = ALL_KINDS; 960 961 /// Queries 962 List<MemberName> getMembers(Class<?> defc, 963 String matchName, Object matchType, 964 int matchFlags, Class<?> lookupClass) { 965 matchFlags &= ALLOWED_FLAGS; 966 String matchSig = null; 967 if (matchType != null) { 968 matchSig = BytecodeDescriptor.unparse(matchType); 969 if (matchSig.startsWith("(")) 970 matchFlags &= ~(ALL_KINDS & ~IS_INVOCABLE); 971 else 972 matchFlags &= ~(ALL_KINDS & ~IS_FIELD); 973 } 974 final int BUF_MAX = 0x2000; 975 int len1 = matchName == null ? 10 : matchType == null ? 4 : 1; 976 MemberName[] buf = newMemberBuffer(len1); 977 int totalCount = 0; 978 ArrayList<MemberName[]> bufs = null; 979 int bufCount = 0; 980 for (;;) { 981 bufCount = MethodHandleNatives.getMembers(defc, 982 matchName, matchSig, matchFlags, 983 lookupClass, 984 totalCount, buf); 985 if (bufCount <= buf.length) { 986 if (bufCount < 0) bufCount = 0; 987 totalCount += bufCount; 988 break; 989 } 990 // JVM returned to us with an intentional overflow! 991 totalCount += buf.length; 992 int excess = bufCount - buf.length; 993 if (bufs == null) bufs = new ArrayList<>(1); 994 bufs.add(buf); 995 int len2 = buf.length; 996 len2 = Math.max(len2, excess); 997 len2 = Math.max(len2, totalCount / 4); 998 buf = newMemberBuffer(Math.min(BUF_MAX, len2)); 999 } 1000 ArrayList<MemberName> result = new ArrayList<>(totalCount); 1001 if (bufs != null) { 1002 for (MemberName[] buf0 : bufs) { 1003 Collections.addAll(result, buf0); 1004 } 1005 } 1006 for (int i = 0; i < bufCount; i++) { 1007 result.add(buf[i]); 1008 } 1009 // Signature matching is not the same as type matching, since 1010 // one signature might correspond to several types. 1011 // So if matchType is a Class or MethodType, refilter the results. 1012 if (matchType != null && matchType != matchSig) { 1013 for (Iterator<MemberName> it = result.iterator(); it.hasNext();) { 1014 MemberName m = it.next(); 1015 if (!matchType.equals(m.getType())) 1016 it.remove(); 1017 } 1018 } 1019 return result; 1020 } 1021 /** Produce a resolved version of the given member. 1022 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1023 * Access checking is performed on behalf of the given {@code lookupClass}. 1024 * If lookup fails or access is not permitted, null is returned. 1025 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in. 1026 */ 1027 private MemberName resolve(byte refKind, MemberName ref, Class<?> lookupClass) { 1028 MemberName m = ref.clone(); // JVM will side-effect the ref 1029 assert(refKind == m.getReferenceKind()); 1030 try { 1031 // There are 4 entities in play here: 1032 // * LC: lookupClass 1033 // * REFC: symbolic reference class (MN.clazz before resolution); 1034 // * DEFC: resolved method holder (MN.clazz after resolution); 1035 // * PTYPES: parameter types (MN.type) 1036 // 1037 // What we care about when resolving a MemberName is consistency between DEFC and PTYPES. 1038 // We do type alias (TA) checks on DEFC to ensure that. DEFC is not known until the JVM 1039 // finishes the resolution, so do TA checks right after MHN.resolve() is over. 1040 // 1041 // All parameters passed by a caller are checked against MH type (PTYPES) on every invocation, 1042 // so it is safe to call a MH from any context. 1043 // 1044 // REFC view on PTYPES doesn't matter, since it is used only as a starting point for resolution and doesn't 1045 // participate in method selection. 1046 m = MethodHandleNatives.resolve(m, lookupClass); 1047 m.checkForTypeAlias(m.getDeclaringClass()); 1048 m.resolution = null; 1049 } catch (ClassNotFoundException | LinkageError ex) { 1050 // JVM reports that the "bytecode behavior" would get an error 1051 assert(!m.isResolved()); 1052 m.resolution = ex; 1053 return m; 1054 } 1055 assert(m.referenceKindIsConsistent()); 1056 m.initResolved(true); 1057 assert(m.vminfoIsConsistent()); 1058 return m; 1059 } 1060 /** Produce a resolved version of the given member. 1061 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1062 * Access checking is performed on behalf of the given {@code lookupClass}. 1063 * If lookup fails or access is not permitted, a {@linkplain ReflectiveOperationException} is thrown. 1064 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in. 1065 */ 1066 public 1067 <NoSuchMemberException extends ReflectiveOperationException> 1068 MemberName resolveOrFail(byte refKind, MemberName m, Class<?> lookupClass, 1069 Class<NoSuchMemberException> nsmClass) 1070 throws IllegalAccessException, NoSuchMemberException { 1071 MemberName result = resolve(refKind, m, lookupClass); 1072 if (result.isResolved()) 1073 return result; 1074 ReflectiveOperationException ex = result.makeAccessException(); 1075 if (ex instanceof IllegalAccessException) throw (IllegalAccessException) ex; 1076 throw nsmClass.cast(ex); 1077 } 1078 /** Produce a resolved version of the given member. 1079 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1080 * Access checking is performed on behalf of the given {@code lookupClass}. 1081 * If lookup fails or access is not permitted, return null. 1082 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in. 1083 */ 1084 public 1085 MemberName resolveOrNull(byte refKind, MemberName m, Class<?> lookupClass) { 1086 MemberName result = resolve(refKind, m, lookupClass); 1087 if (result.isResolved()) 1088 return result; 1089 return null; 1090 } 1091 /** Return a list of all methods defined by the given class. 1092 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1093 * Access checking is performed on behalf of the given {@code lookupClass}. 1094 * Inaccessible members are not added to the last. 1095 */ 1096 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers, 1097 Class<?> lookupClass) { 1098 return getMethods(defc, searchSupers, null, null, lookupClass); 1099 } 1100 /** Return a list of matching methods defined by the given class. 1101 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1102 * Returned methods will match the name (if not null) and the type (if not null). 1103 * Access checking is performed on behalf of the given {@code lookupClass}. 1104 * Inaccessible members are not added to the last. 1105 */ 1106 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers, 1107 String name, MethodType type, Class<?> lookupClass) { 1108 int matchFlags = IS_METHOD | (searchSupers ? SEARCH_ALL_SUPERS : 0); 1109 return getMembers(defc, name, type, matchFlags, lookupClass); 1110 } 1111 /** Return a list of all constructors defined by the given class. 1112 * Access checking is performed on behalf of the given {@code lookupClass}. 1113 * Inaccessible members are not added to the last. 1114 */ 1115 public List<MemberName> getConstructors(Class<?> defc, Class<?> lookupClass) { 1116 return getMembers(defc, null, null, IS_CONSTRUCTOR, lookupClass); 1117 } 1118 /** Return a list of all fields defined by the given class. 1119 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1120 * Access checking is performed on behalf of the given {@code lookupClass}. 1121 * Inaccessible members are not added to the last. 1122 */ 1123 public List<MemberName> getFields(Class<?> defc, boolean searchSupers, 1124 Class<?> lookupClass) { 1125 return getFields(defc, searchSupers, null, null, lookupClass); 1126 } 1127 /** Return a list of all fields defined by the given class. 1128 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1129 * Returned fields will match the name (if not null) and the type (if not null). 1130 * Access checking is performed on behalf of the given {@code lookupClass}. 1131 * Inaccessible members are not added to the last. 1132 */ 1133 public List<MemberName> getFields(Class<?> defc, boolean searchSupers, 1134 String name, Class<?> type, Class<?> lookupClass) { 1135 int matchFlags = IS_FIELD | (searchSupers ? SEARCH_ALL_SUPERS : 0); 1136 return getMembers(defc, name, type, matchFlags, lookupClass); 1137 } 1138 /** Return a list of all nested types defined by the given class. 1139 * Super types are searched (for inherited members) if {@code searchSupers} is true. 1140 * Access checking is performed on behalf of the given {@code lookupClass}. 1141 * Inaccessible members are not added to the last. 1142 */ 1143 public List<MemberName> getNestedTypes(Class<?> defc, boolean searchSupers, 1144 Class<?> lookupClass) { 1145 int matchFlags = IS_TYPE | (searchSupers ? SEARCH_ALL_SUPERS : 0); 1146 return getMembers(defc, null, null, matchFlags, lookupClass); 1147 } 1148 private static MemberName[] newMemberBuffer(int length) { 1149 MemberName[] buf = new MemberName[length]; 1150 // fill the buffer with dummy structs for the JVM to fill in 1151 for (int i = 0; i < length; i++) 1152 buf[i] = new MemberName(); 1153 return buf; 1154 } 1155 } 1156} 1157