1 /* 2 * Copyright (c) 1994, 2014, 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; 27 28 import java.lang.reflect.AnnotatedElement; 29 import java.lang.reflect.Array; 30 import java.lang.reflect.GenericArrayType; 31 import java.lang.reflect.GenericDeclaration; 32 import java.lang.reflect.Member; 33 import java.lang.reflect.Field; 34 import java.lang.reflect.Executable; 35 import java.lang.reflect.Method; 36 import java.lang.reflect.Constructor; 37 import java.lang.reflect.Modifier; 38 import java.lang.reflect.Type; 39 import java.lang.reflect.TypeVariable; 40 import java.lang.reflect.InvocationTargetException; 41 import java.lang.reflect.AnnotatedType; 42 import java.lang.ref.SoftReference; 43 import java.io.InputStream; 44 import java.io.ObjectStreamField; 45 import java.security.AccessController; 46 import java.security.PrivilegedAction; 47 import java.util.ArrayList; 48 import java.util.Arrays; 49 import java.util.Collection; 50 import java.util.HashSet; 51 import java.util.LinkedHashMap; 52 import java.util.List; 53 import java.util.Set; 54 import java.util.Map; 55 import java.util.HashMap; 56 import java.util.Objects; 57 import java.util.StringJoiner; 58 import sun.misc.Unsafe; 59 import sun.reflect.CallerSensitive; 60 import sun.reflect.ConstantPool; 61 import sun.reflect.Reflection; 62 import sun.reflect.ReflectionFactory; 63 import sun.reflect.generics.factory.CoreReflectionFactory; 64 import sun.reflect.generics.factory.GenericsFactory; 65 import sun.reflect.generics.repository.ClassRepository; 66 import sun.reflect.generics.repository.MethodRepository; 67 import sun.reflect.generics.repository.ConstructorRepository; 68 import sun.reflect.generics.scope.ClassScope; 69 import sun.security.util.SecurityConstants; 70 import java.lang.annotation.Annotation; 71 import java.lang.reflect.Proxy; 72 import sun.reflect.annotation.*; 73 import sun.reflect.misc.ReflectUtil; 74 75 /** 76 * Instances of the class {@code Class} represent classes and 77 * interfaces in a running Java application. An enum is a kind of 78 * class and an annotation is a kind of interface. Every array also 79 * belongs to a class that is reflected as a {@code Class} object 80 * that is shared by all arrays with the same element type and number 81 * of dimensions. The primitive Java types ({@code boolean}, 82 * {@code byte}, {@code char}, {@code short}, 83 * {@code int}, {@code long}, {@code float}, and 84 * {@code double}), and the keyword {@code void} are also 85 * represented as {@code Class} objects. 86 * 87 * <p> {@code Class} has no public constructor. Instead {@code Class} 88 * objects are constructed automatically by the Java Virtual Machine as classes 89 * are loaded and by calls to the {@code defineClass} method in the class 90 * loader. 91 * 92 * <p> The following example uses a {@code Class} object to print the 93 * class name of an object: 94 * 95 * <blockquote><pre> 96 * void printClassName(Object obj) { 97 * System.out.println("The class of " + obj + 98 * " is " + obj.getClass().getName()); 99 * } 100 * </pre></blockquote> 101 * 102 * <p> It is also possible to get the {@code Class} object for a named 103 * type (or for void) using a class literal. See Section 15.8.2 of 104 * <cite>The Java™ Language Specification</cite>. 105 * For example: 106 * 107 * <blockquote> 108 * {@code System.out.println("The name of class Foo is: "+Foo.class.getName());} 109 * </blockquote> 110 * 111 * @param <T> the type of the class modeled by this {@code Class} 112 * object. For example, the type of {@code String.class} is {@code 113 * Class<String>}. Use {@code Class<?>} if the class being modeled is 114 * unknown. 115 * 116 * @author unascribed 117 * @see java.lang.ClassLoader#defineClass(byte[], int, int) 118 * @since 1.0 119 */ 120 public final class Class<T> implements java.io.Serializable, 121 GenericDeclaration, 122 Type, 123 AnnotatedElement { 124 private static final int ANNOTATION= 0x00002000; 125 private static final int ENUM = 0x00004000; 126 private static final int SYNTHETIC = 0x00001000; 127 128 private static native void registerNatives(); 129 static { 130 registerNatives(); 131 } 132 133 /* 134 * Private constructor. Only the Java Virtual Machine creates Class objects. 135 * This constructor is not used and prevents the default constructor being 136 * generated. 137 */ 138 private Class(ClassLoader loader, Class<?> arrayComponentType) { 139 // Initialize final field for classLoader. The initialization value of non-null 140 // prevents future JIT optimizations from assuming this final field is null. 141 classLoader = loader; 142 componentType = arrayComponentType; 143 } 144 145 /** 146 * Converts the object to a string. The string representation is the 147 * string "class" or "interface", followed by a space, and then by the 148 * fully qualified name of the class in the format returned by 149 * {@code getName}. If this {@code Class} object represents a 150 * primitive type, this method returns the name of the primitive type. If 151 * this {@code Class} object represents void this method returns 152 * "void". If this {@code Class} object represents an array type, 153 * this method returns "class " followed by {@code getName}. 154 * 155 * @return a string representation of this class object. 156 */ 157 public String toString() { 158 return (isInterface() ? "interface " : (isPrimitive() ? "" : "class ")) 159 + getName(); 160 } 161 162 /** 163 * Returns a string describing this {@code Class}, including 164 * information about modifiers and type parameters. 165 * 166 * The string is formatted as a list of type modifiers, if any, 167 * followed by the kind of type (empty string for primitive types 168 * and {@code class}, {@code enum}, {@code interface}, or 169 * <code>@</code>{@code interface}, as appropriate), followed 170 * by the type's name, followed by an angle-bracketed 171 * comma-separated list of the type's type parameters, if any. 172 * 173 * A space is used to separate modifiers from one another and to 174 * separate any modifiers from the kind of type. The modifiers 175 * occur in canonical order. If there are no type parameters, the 176 * type parameter list is elided. 177 * 178 * For an array type, the string starts with the type name, 179 * followed by an angle-bracketed comma-separated list of the 180 * type's type parameters, if any, followed by a sequence of 181 * {@code []} characters, one set of brackets per dimension of 182 * the array. 183 * 184 * <p>Note that since information about the runtime representation 185 * of a type is being generated, modifiers not present on the 186 * originating source code or illegal on the originating source 187 * code may be present. 188 * 189 * @return a string describing this {@code Class}, including 190 * information about modifiers and type parameters 191 * 192 * @since 1.8 193 */ 194 public String toGenericString() { 195 if (isPrimitive()) { 196 return toString(); 197 } else { 198 StringBuilder sb = new StringBuilder(); 199 Class<?> component = this; 200 int arrayDepth = 0; 201 202 if (isArray()) { 203 do { 204 arrayDepth++; 205 component = component.getComponentType(); 206 } while (component.isArray()); 207 sb.append(component.getName()); 208 } else { 209 // Class modifiers are a superset of interface modifiers 210 int modifiers = getModifiers() & Modifier.classModifiers(); 211 if (modifiers != 0) { 212 sb.append(Modifier.toString(modifiers)); 213 sb.append(' '); 214 } 215 216 if (isAnnotation()) { 217 sb.append('@'); 218 } 219 if (isInterface()) { // Note: all annotation types are interfaces 220 sb.append("interface"); 221 } else { 222 if (isEnum()) 223 sb.append("enum"); 224 else 225 sb.append("class"); 226 } 227 sb.append(' '); 228 sb.append(getName()); 229 } 230 231 TypeVariable<?>[] typeparms = component.getTypeParameters(); 232 if (typeparms.length > 0) { 233 boolean first = true; 234 sb.append('<'); 235 for(TypeVariable<?> typeparm: typeparms) { 236 if (!first) 237 sb.append(','); 238 sb.append(typeparm.getTypeName()); 239 first = false; 240 } 241 sb.append('>'); 242 } 243 244 for (int i = 0; i < arrayDepth; i++) 245 sb.append("[]"); 246 247 return sb.toString(); 248 } 249 } 250 251 /** 252 * Returns the {@code Class} object associated with the class or 253 * interface with the given string name. Invoking this method is 254 * equivalent to: 255 * 256 * <blockquote> 257 * {@code Class.forName(className, true, currentLoader)} 258 * </blockquote> 259 * 260 * where {@code currentLoader} denotes the defining class loader of 261 * the current class. 262 * 263 * <p> For example, the following code fragment returns the 264 * runtime {@code Class} descriptor for the class named 265 * {@code java.lang.Thread}: 266 * 267 * <blockquote> 268 * {@code Class t = Class.forName("java.lang.Thread")} 269 * </blockquote> 270 * <p> 271 * A call to {@code forName("X")} causes the class named 272 * {@code X} to be initialized. 273 * 274 * @param className the fully qualified name of the desired class. 275 * @return the {@code Class} object for the class with the 276 * specified name. 277 * @exception LinkageError if the linkage fails 278 * @exception ExceptionInInitializerError if the initialization provoked 279 * by this method fails 280 * @exception ClassNotFoundException if the class cannot be located 281 */ 282 @CallerSensitive 283 public static Class<?> forName(String className) 284 throws ClassNotFoundException { 285 Class<?> caller = Reflection.getCallerClass(); 286 return forName0(className, true, ClassLoader.getClassLoader(caller), caller); 287 } 288 289 290 /** 291 * Returns the {@code Class} object associated with the class or 292 * interface with the given string name, using the given class loader. 293 * Given the fully qualified name for a class or interface (in the same 294 * format returned by {@code getName}) this method attempts to 295 * locate, load, and link the class or interface. The specified class 296 * loader is used to load the class or interface. If the parameter 297 * {@code loader} is null, the class is loaded through the bootstrap 298 * class loader. The class is initialized only if the 299 * {@code initialize} parameter is {@code true} and if it has 300 * not been initialized earlier. 301 * 302 * <p> If {@code name} denotes a primitive type or void, an attempt 303 * will be made to locate a user-defined class in the unnamed package whose 304 * name is {@code name}. Therefore, this method cannot be used to 305 * obtain any of the {@code Class} objects representing primitive 306 * types or void. 307 * 308 * <p> If {@code name} denotes an array class, the component type of 309 * the array class is loaded but not initialized. 310 * 311 * <p> For example, in an instance method the expression: 312 * 313 * <blockquote> 314 * {@code Class.forName("Foo")} 315 * </blockquote> 316 * 317 * is equivalent to: 318 * 319 * <blockquote> 320 * {@code Class.forName("Foo", true, this.getClass().getClassLoader())} 321 * </blockquote> 322 * 323 * Note that this method throws errors related to loading, linking or 324 * initializing as specified in Sections 12.2, 12.3 and 12.4 of <em>The 325 * Java Language Specification</em>. 326 * Note that this method does not check whether the requested class 327 * is accessible to its caller. 328 * 329 * <p> If the {@code loader} is {@code null}, and a security 330 * manager is present, and the caller's class loader is not null, then this 331 * method calls the security manager's {@code checkPermission} method 332 * with a {@code RuntimePermission("getClassLoader")} permission to 333 * ensure it's ok to access the bootstrap class loader. 334 * 335 * @param name fully qualified name of the desired class 336 * @param initialize if {@code true} the class will be initialized. 337 * See Section 12.4 of <em>The Java Language Specification</em>. 338 * @param loader class loader from which the class must be loaded 339 * @return class object representing the desired class 340 * 341 * @exception LinkageError if the linkage fails 342 * @exception ExceptionInInitializerError if the initialization provoked 343 * by this method fails 344 * @exception ClassNotFoundException if the class cannot be located by 345 * the specified class loader 346 * 347 * @see java.lang.Class#forName(String) 348 * @see java.lang.ClassLoader 349 * @since 1.2 350 */ 351 @CallerSensitive 352 public static Class<?> forName(String name, boolean initialize, 353 ClassLoader loader) 354 throws ClassNotFoundException 355 { 356 Class<?> caller = null; 357 SecurityManager sm = System.getSecurityManager(); 358 if (sm != null) { 359 // Reflective call to get caller class is only needed if a security manager 360 // is present. Avoid the overhead of making this call otherwise. 361 caller = Reflection.getCallerClass(); 362 if (sun.misc.VM.isSystemDomainLoader(loader)) { 363 ClassLoader ccl = ClassLoader.getClassLoader(caller); 364 if (!sun.misc.VM.isSystemDomainLoader(ccl)) { 365 sm.checkPermission( 366 SecurityConstants.GET_CLASSLOADER_PERMISSION); 367 } 368 } 369 } 370 return forName0(name, initialize, loader, caller); 371 } 372 373 /** Called after security check for system loader access checks have been made. */ 374 private static native Class<?> forName0(String name, boolean initialize, 375 ClassLoader loader, 376 Class<?> caller) 377 throws ClassNotFoundException; 378 379 /** 380 * Creates a new instance of the class represented by this {@code Class} 381 * object. The class is instantiated as if by a {@code new} 382 * expression with an empty argument list. The class is initialized if it 383 * has not already been initialized. 384 * 385 * <p>Note that this method propagates any exception thrown by the 386 * nullary constructor, including a checked exception. Use of 387 * this method effectively bypasses the compile-time exception 388 * checking that would otherwise be performed by the compiler. 389 * The {@link 390 * java.lang.reflect.Constructor#newInstance(java.lang.Object...) 391 * Constructor.newInstance} method avoids this problem by wrapping 392 * any exception thrown by the constructor in a (checked) {@link 393 * java.lang.reflect.InvocationTargetException}. 394 * 395 * @return a newly allocated instance of the class represented by this 396 * object. 397 * @throws IllegalAccessException if the class or its nullary 398 * constructor is not accessible. 399 * @throws InstantiationException 400 * if this {@code Class} represents an abstract class, 401 * an interface, an array class, a primitive type, or void; 402 * or if the class has no nullary constructor; 403 * or if the instantiation fails for some other reason. 404 * @throws ExceptionInInitializerError if the initialization 405 * provoked by this method fails. 406 * @throws SecurityException 407 * If a security manager, <i>s</i>, is present and 408 * the caller's class loader is not the same as or an 409 * ancestor of the class loader for the current class and 410 * invocation of {@link SecurityManager#checkPackageAccess 411 * s.checkPackageAccess()} denies access to the package 412 * of this class. 413 */ 414 @CallerSensitive 415 public T newInstance() 416 throws InstantiationException, IllegalAccessException 417 { 418 if (System.getSecurityManager() != null) { 419 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), false); 420 } 421 422 // NOTE: the following code may not be strictly correct under 423 // the current Java memory model. 424 425 // Constructor lookup 426 if (cachedConstructor == null) { 427 if (this == Class.class) { 428 throw new IllegalAccessException( 429 "Can not call newInstance() on the Class for java.lang.Class" 430 ); 431 } 432 try { 433 Class<?>[] empty = {}; 434 final Constructor<T> c = getConstructor0(empty, Member.DECLARED); 435 // Disable accessibility checks on the constructor 436 // since we have to do the security check here anyway 437 // (the stack depth is wrong for the Constructor's 438 // security check to work) 439 java.security.AccessController.doPrivileged( 440 new java.security.PrivilegedAction<Void>() { 441 public Void run() { 442 c.setAccessible(true); 443 return null; 444 } 445 }); 446 cachedConstructor = c; 447 } catch (NoSuchMethodException e) { 448 throw (InstantiationException) 449 new InstantiationException(getName()).initCause(e); 450 } 451 } 452 Constructor<T> tmpConstructor = cachedConstructor; 453 // Security check (same as in java.lang.reflect.Constructor) 454 int modifiers = tmpConstructor.getModifiers(); 455 if (!Reflection.quickCheckMemberAccess(this, modifiers)) { 456 Class<?> caller = Reflection.getCallerClass(); 457 if (newInstanceCallerCache != caller) { 458 Reflection.ensureMemberAccess(caller, this, null, modifiers); 459 newInstanceCallerCache = caller; 460 } 461 } 462 // Run constructor 463 try { 464 return tmpConstructor.newInstance((Object[])null); 465 } catch (InvocationTargetException e) { 466 Unsafe.getUnsafe().throwException(e.getTargetException()); 467 // Not reached 468 return null; 469 } 470 } 471 private volatile transient Constructor<T> cachedConstructor; 472 private volatile transient Class<?> newInstanceCallerCache; 473 474 475 /** 476 * Determines if the specified {@code Object} is assignment-compatible 477 * with the object represented by this {@code Class}. This method is 478 * the dynamic equivalent of the Java language {@code instanceof} 479 * operator. The method returns {@code true} if the specified 480 * {@code Object} argument is non-null and can be cast to the 481 * reference type represented by this {@code Class} object without 482 * raising a {@code ClassCastException.} It returns {@code false} 483 * otherwise. 484 * 485 * <p> Specifically, if this {@code Class} object represents a 486 * declared class, this method returns {@code true} if the specified 487 * {@code Object} argument is an instance of the represented class (or 488 * of any of its subclasses); it returns {@code false} otherwise. If 489 * this {@code Class} object represents an array class, this method 490 * returns {@code true} if the specified {@code Object} argument 491 * can be converted to an object of the array class by an identity 492 * conversion or by a widening reference conversion; it returns 493 * {@code false} otherwise. If this {@code Class} object 494 * represents an interface, this method returns {@code true} if the 495 * class or any superclass of the specified {@code Object} argument 496 * implements this interface; it returns {@code false} otherwise. If 497 * this {@code Class} object represents a primitive type, this method 498 * returns {@code false}. 499 * 500 * @param obj the object to check 501 * @return true if {@code obj} is an instance of this class 502 * 503 * @since 1.1 504 */ 505 public native boolean isInstance(Object obj); 506 507 508 /** 509 * Determines if the class or interface represented by this 510 * {@code Class} object is either the same as, or is a superclass or 511 * superinterface of, the class or interface represented by the specified 512 * {@code Class} parameter. It returns {@code true} if so; 513 * otherwise it returns {@code false}. If this {@code Class} 514 * object represents a primitive type, this method returns 515 * {@code true} if the specified {@code Class} parameter is 516 * exactly this {@code Class} object; otherwise it returns 517 * {@code false}. 518 * 519 * <p> Specifically, this method tests whether the type represented by the 520 * specified {@code Class} parameter can be converted to the type 521 * represented by this {@code Class} object via an identity conversion 522 * or via a widening reference conversion. See <em>The Java Language 523 * Specification</em>, sections 5.1.1 and 5.1.4 , for details. 524 * 525 * @param cls the {@code Class} object to be checked 526 * @return the {@code boolean} value indicating whether objects of the 527 * type {@code cls} can be assigned to objects of this class 528 * @exception NullPointerException if the specified Class parameter is 529 * null. 530 * @since 1.1 531 */ 532 public native boolean isAssignableFrom(Class<?> cls); 533 534 535 /** 536 * Determines if the specified {@code Class} object represents an 537 * interface type. 538 * 539 * @return {@code true} if this object represents an interface; 540 * {@code false} otherwise. 541 */ 542 public native boolean isInterface(); 543 544 545 /** 546 * Determines if this {@code Class} object represents an array class. 547 * 548 * @return {@code true} if this object represents an array class; 549 * {@code false} otherwise. 550 * @since 1.1 551 */ 552 public native boolean isArray(); 553 554 555 /** 556 * Determines if the specified {@code Class} object represents a 557 * primitive type. 558 * 559 * <p> There are nine predefined {@code Class} objects to represent 560 * the eight primitive types and void. These are created by the Java 561 * Virtual Machine, and have the same names as the primitive types that 562 * they represent, namely {@code boolean}, {@code byte}, 563 * {@code char}, {@code short}, {@code int}, 564 * {@code long}, {@code float}, and {@code double}. 565 * 566 * <p> These objects may only be accessed via the following public static 567 * final variables, and are the only {@code Class} objects for which 568 * this method returns {@code true}. 569 * 570 * @return true if and only if this class represents a primitive type 571 * 572 * @see java.lang.Boolean#TYPE 573 * @see java.lang.Character#TYPE 574 * @see java.lang.Byte#TYPE 575 * @see java.lang.Short#TYPE 576 * @see java.lang.Integer#TYPE 577 * @see java.lang.Long#TYPE 578 * @see java.lang.Float#TYPE 579 * @see java.lang.Double#TYPE 580 * @see java.lang.Void#TYPE 581 * @since 1.1 582 */ 583 public native boolean isPrimitive(); 584 585 /** 586 * Returns true if this {@code Class} object represents an annotation 587 * type. Note that if this method returns true, {@link #isInterface()} 588 * would also return true, as all annotation types are also interfaces. 589 * 590 * @return {@code true} if this class object represents an annotation 591 * type; {@code false} otherwise 592 * @since 1.5 593 */ 594 public boolean isAnnotation() { 595 return (getModifiers() & ANNOTATION) != 0; 596 } 597 598 /** 599 * Returns {@code true} if this class is a synthetic class; 600 * returns {@code false} otherwise. 601 * @return {@code true} if and only if this class is a synthetic class as 602 * defined by the Java Language Specification. 603 * @jls 13.1 The Form of a Binary 604 * @since 1.5 605 */ 606 public boolean isSynthetic() { 607 return (getModifiers() & SYNTHETIC) != 0; 608 } 609 610 /** 611 * Returns the name of the entity (class, interface, array class, 612 * primitive type, or void) represented by this {@code Class} object, 613 * as a {@code String}. 614 * 615 * <p> If this class object represents a reference type that is not an 616 * array type then the binary name of the class is returned, as specified 617 * by 618 * <cite>The Java™ Language Specification</cite>. 619 * 620 * <p> If this class object represents a primitive type or void, then the 621 * name returned is a {@code String} equal to the Java language 622 * keyword corresponding to the primitive type or void. 623 * 624 * <p> If this class object represents a class of arrays, then the internal 625 * form of the name consists of the name of the element type preceded by 626 * one or more '{@code [}' characters representing the depth of the array 627 * nesting. The encoding of element type names is as follows: 628 * 629 * <blockquote><table summary="Element types and encodings"> 630 * <tr><th> Element Type <th> <th> Encoding 631 * <tr><td> boolean <td> <td align=center> Z 632 * <tr><td> byte <td> <td align=center> B 633 * <tr><td> char <td> <td align=center> C 634 * <tr><td> class or interface 635 * <td> <td align=center> L<i>classname</i>; 636 * <tr><td> double <td> <td align=center> D 637 * <tr><td> float <td> <td align=center> F 638 * <tr><td> int <td> <td align=center> I 639 * <tr><td> long <td> <td align=center> J 640 * <tr><td> short <td> <td align=center> S 641 * </table></blockquote> 642 * 643 * <p> The class or interface name <i>classname</i> is the binary name of 644 * the class specified above. 645 * 646 * <p> Examples: 647 * <blockquote><pre> 648 * String.class.getName() 649 * returns "java.lang.String" 650 * byte.class.getName() 651 * returns "byte" 652 * (new Object[3]).getClass().getName() 653 * returns "[Ljava.lang.Object;" 654 * (new int[3][4][5][6][7][8][9]).getClass().getName() 655 * returns "[[[[[[[I" 656 * </pre></blockquote> 657 * 658 * @return the name of the class or interface 659 * represented by this object. 660 */ 661 public String getName() { 662 String name = this.name; 663 if (name == null) 664 this.name = name = getName0(); 665 return name; 666 } 667 668 // cache the name to reduce the number of calls into the VM 669 private transient String name; 670 private native String getName0(); 671 672 /** 673 * Returns the class loader for the class. Some implementations may use 674 * null to represent the bootstrap class loader. This method will return 675 * null in such implementations if this class was loaded by the bootstrap 676 * class loader. 677 * 678 * <p> If a security manager is present, and the caller's class loader is 679 * not null and the caller's class loader is not the same as or an ancestor of 680 * the class loader for the class whose class loader is requested, then 681 * this method calls the security manager's {@code checkPermission} 682 * method with a {@code RuntimePermission("getClassLoader")} 683 * permission to ensure it's ok to access the class loader for the class. 684 * 685 * <p>If this object 686 * represents a primitive type or void, null is returned. 687 * 688 * @return the class loader that loaded the class or interface 689 * represented by this object. 690 * @throws SecurityException 691 * if a security manager exists and its 692 * {@code checkPermission} method denies 693 * access to the class loader for the class. 694 * @see java.lang.ClassLoader 695 * @see SecurityManager#checkPermission 696 * @see java.lang.RuntimePermission 697 */ 698 @CallerSensitive 699 public ClassLoader getClassLoader() { 700 ClassLoader cl = getClassLoader0(); 701 if (cl == null) 702 return null; 703 SecurityManager sm = System.getSecurityManager(); 704 if (sm != null) { 705 ClassLoader.checkClassLoaderPermission(cl, Reflection.getCallerClass()); 706 } 707 return cl; 708 } 709 710 // Package-private to allow ClassLoader access 711 ClassLoader getClassLoader0() { return classLoader; } 712 713 // Initialized in JVM not by private constructor 714 // This field is filtered from reflection access, i.e. getDeclaredField 715 // will throw NoSuchFieldException 716 private final ClassLoader classLoader; 717 718 /** 719 * Returns an array of {@code TypeVariable} objects that represent the 720 * type variables declared by the generic declaration represented by this 721 * {@code GenericDeclaration} object, in declaration order. Returns an 722 * array of length 0 if the underlying generic declaration declares no type 723 * variables. 724 * 725 * @return an array of {@code TypeVariable} objects that represent 726 * the type variables declared by this generic declaration 727 * @throws java.lang.reflect.GenericSignatureFormatError if the generic 728 * signature of this generic declaration does not conform to 729 * the format specified in 730 * <cite>The Java™ Virtual Machine Specification</cite> 731 * @since 1.5 732 */ 733 @SuppressWarnings("unchecked") 734 public TypeVariable<Class<T>>[] getTypeParameters() { 735 ClassRepository info = getGenericInfo(); 736 if (info != null) 737 return (TypeVariable<Class<T>>[])info.getTypeParameters(); 738 else 739 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0]; 740 } 741 742 743 /** 744 * Returns the {@code Class} representing the direct superclass of the 745 * entity (class, interface, primitive type or void) represented by 746 * this {@code Class}. If this {@code Class} represents either the 747 * {@code Object} class, an interface, a primitive type, or void, then 748 * null is returned. If this object represents an array class then the 749 * {@code Class} object representing the {@code Object} class is 750 * returned. 751 * 752 * @return the direct superclass of the class represented by this object 753 */ 754 public native Class<? super T> getSuperclass(); 755 756 757 /** 758 * Returns the {@code Type} representing the direct superclass of 759 * the entity (class, interface, primitive type or void) represented by 760 * this {@code Class}. 761 * 762 * <p>If the superclass is a parameterized type, the {@code Type} 763 * object returned must accurately reflect the actual type 764 * parameters used in the source code. The parameterized type 765 * representing the superclass is created if it had not been 766 * created before. See the declaration of {@link 767 * java.lang.reflect.ParameterizedType ParameterizedType} for the 768 * semantics of the creation process for parameterized types. If 769 * this {@code Class} represents either the {@code Object} 770 * class, an interface, a primitive type, or void, then null is 771 * returned. If this object represents an array class then the 772 * {@code Class} object representing the {@code Object} class is 773 * returned. 774 * 775 * @throws java.lang.reflect.GenericSignatureFormatError if the generic 776 * class signature does not conform to the format specified in 777 * <cite>The Java™ Virtual Machine Specification</cite> 778 * @throws TypeNotPresentException if the generic superclass 779 * refers to a non-existent type declaration 780 * @throws java.lang.reflect.MalformedParameterizedTypeException if the 781 * generic superclass refers to a parameterized type that cannot be 782 * instantiated for any reason 783 * @return the direct superclass of the class represented by this object 784 * @since 1.5 785 */ 786 public Type getGenericSuperclass() { 787 ClassRepository info = getGenericInfo(); 788 if (info == null) { 789 return getSuperclass(); 790 } 791 792 // Historical irregularity: 793 // Generic signature marks interfaces with superclass = Object 794 // but this API returns null for interfaces 795 if (isInterface()) { 796 return null; 797 } 798 799 return info.getSuperclass(); 800 } 801 802 /** 803 * Gets the package for this class. The class loader of this class is used 804 * to find the package. If the class was loaded by the bootstrap class 805 * loader the set of packages loaded from CLASSPATH is searched to find the 806 * package of the class. Null is returned if no package object was created 807 * by the class loader of this class. 808 * 809 * <p> Packages have attributes for versions and specifications only if the 810 * information was defined in the manifests that accompany the classes, and 811 * if the class loader created the package instance with the attributes 812 * from the manifest. 813 * 814 * @return the package of the class, or null if no package 815 * information is available from the archive or codebase. 816 */ 817 public Package getPackage() { 818 return Package.getPackage(this); 819 } 820 821 822 /** 823 * Returns the interfaces directly implemented by the class or interface 824 * represented by this object. 825 * 826 * <p>If this object represents a class, the return value is an array 827 * containing objects representing all interfaces directly implemented by 828 * the class. The order of the interface objects in the array corresponds 829 * to the order of the interface names in the {@code implements} clause of 830 * the declaration of the class represented by this object. For example, 831 * given the declaration: 832 * <blockquote> 833 * {@code class Shimmer implements FloorWax, DessertTopping { ... }} 834 * </blockquote> 835 * suppose the value of {@code s} is an instance of 836 * {@code Shimmer}; the value of the expression: 837 * <blockquote> 838 * {@code s.getClass().getInterfaces()[0]} 839 * </blockquote> 840 * is the {@code Class} object that represents interface 841 * {@code FloorWax}; and the value of: 842 * <blockquote> 843 * {@code s.getClass().getInterfaces()[1]} 844 * </blockquote> 845 * is the {@code Class} object that represents interface 846 * {@code DessertTopping}. 847 * 848 * <p>If this object represents an interface, the array contains objects 849 * representing all interfaces directly extended by the interface. The 850 * order of the interface objects in the array corresponds to the order of 851 * the interface names in the {@code extends} clause of the declaration of 852 * the interface represented by this object. 853 * 854 * <p>If this object represents a class or interface that implements no 855 * interfaces, the method returns an array of length 0. 856 * 857 * <p>If this object represents a primitive type or void, the method 858 * returns an array of length 0. 859 * 860 * <p>If this {@code Class} object represents an array type, the 861 * interfaces {@code Cloneable} and {@code java.io.Serializable} are 862 * returned in that order. 863 * 864 * @return an array of interfaces directly implemented by this class 865 */ 866 public Class<?>[] getInterfaces() { 867 ReflectionData<T> rd = reflectionData(); 868 if (rd == null) { 869 // no cloning required 870 return getInterfaces0(); 871 } else { 872 Class<?>[] interfaces = rd.interfaces; 873 if (interfaces == null) { 874 interfaces = getInterfaces0(); 875 rd.interfaces = interfaces; 876 } 877 // defensively copy before handing over to user code 878 return interfaces.clone(); 879 } 880 } 881 882 private native Class<?>[] getInterfaces0(); 883 884 /** 885 * Returns the {@code Type}s representing the interfaces 886 * directly implemented by the class or interface represented by 887 * this object. 888 * 889 * <p>If a superinterface is a parameterized type, the 890 * {@code Type} object returned for it must accurately reflect 891 * the actual type parameters used in the source code. The 892 * parameterized type representing each superinterface is created 893 * if it had not been created before. See the declaration of 894 * {@link java.lang.reflect.ParameterizedType ParameterizedType} 895 * for the semantics of the creation process for parameterized 896 * types. 897 * 898 * <p>If this object represents a class, the return value is an array 899 * containing objects representing all interfaces directly implemented by 900 * the class. The order of the interface objects in the array corresponds 901 * to the order of the interface names in the {@code implements} clause of 902 * the declaration of the class represented by this object. 903 * 904 * <p>If this object represents an interface, the array contains objects 905 * representing all interfaces directly extended by the interface. The 906 * order of the interface objects in the array corresponds to the order of 907 * the interface names in the {@code extends} clause of the declaration of 908 * the interface represented by this object. 909 * 910 * <p>If this object represents a class or interface that implements no 911 * interfaces, the method returns an array of length 0. 912 * 913 * <p>If this object represents a primitive type or void, the method 914 * returns an array of length 0. 915 * 916 * <p>If this {@code Class} object represents an array type, the 917 * interfaces {@code Cloneable} and {@code java.io.Serializable} are 918 * returned in that order. 919 * 920 * @throws java.lang.reflect.GenericSignatureFormatError 921 * if the generic class signature does not conform to the format 922 * specified in 923 * <cite>The Java™ Virtual Machine Specification</cite> 924 * @throws TypeNotPresentException if any of the generic 925 * superinterfaces refers to a non-existent type declaration 926 * @throws java.lang.reflect.MalformedParameterizedTypeException 927 * if any of the generic superinterfaces refer to a parameterized 928 * type that cannot be instantiated for any reason 929 * @return an array of interfaces directly implemented by this class 930 * @since 1.5 931 */ 932 public Type[] getGenericInterfaces() { 933 ClassRepository info = getGenericInfo(); 934 return (info == null) ? getInterfaces() : info.getSuperInterfaces(); 935 } 936 937 938 /** 939 * Returns the {@code Class} representing the component type of an 940 * array. If this class does not represent an array class this method 941 * returns null. 942 * 943 * @return the {@code Class} representing the component type of this 944 * class if this class is an array 945 * @see java.lang.reflect.Array 946 * @since 1.1 947 */ 948 public Class<?> getComponentType() { 949 // Only return for array types. Storage may be reused for Class for instance types. 950 if (isArray()) { 951 return componentType; 952 } else { 953 return null; 954 } 955 } 956 957 private final Class<?> componentType; 958 959 960 /** 961 * Returns the Java language modifiers for this class or interface, encoded 962 * in an integer. The modifiers consist of the Java Virtual Machine's 963 * constants for {@code public}, {@code protected}, 964 * {@code private}, {@code final}, {@code static}, 965 * {@code abstract} and {@code interface}; they should be decoded 966 * using the methods of class {@code Modifier}. 967 * 968 * <p> If the underlying class is an array class, then its 969 * {@code public}, {@code private} and {@code protected} 970 * modifiers are the same as those of its component type. If this 971 * {@code Class} represents a primitive type or void, its 972 * {@code public} modifier is always {@code true}, and its 973 * {@code protected} and {@code private} modifiers are always 974 * {@code false}. If this object represents an array class, a 975 * primitive type or void, then its {@code final} modifier is always 976 * {@code true} and its interface modifier is always 977 * {@code false}. The values of its other modifiers are not determined 978 * by this specification. 979 * 980 * <p> The modifier encodings are defined in <em>The Java Virtual Machine 981 * Specification</em>, table 4.1. 982 * 983 * @return the {@code int} representing the modifiers for this class 984 * @see java.lang.reflect.Modifier 985 * @since 1.1 986 */ 987 public native int getModifiers(); 988 989 990 /** 991 * Gets the signers of this class. 992 * 993 * @return the signers of this class, or null if there are no signers. In 994 * particular, this method returns null if this object represents 995 * a primitive type or void. 996 * @since 1.1 997 */ 998 public native Object[] getSigners(); 999 1000 1001 /** 1002 * Set the signers of this class. 1003 */ 1004 native void setSigners(Object[] signers); 1005 1006 1007 /** 1008 * If this {@code Class} object represents a local or anonymous 1009 * class within a method, returns a {@link 1010 * java.lang.reflect.Method Method} object representing the 1011 * immediately enclosing method of the underlying class. Returns 1012 * {@code null} otherwise. 1013 * 1014 * In particular, this method returns {@code null} if the underlying 1015 * class is a local or anonymous class immediately enclosed by a type 1016 * declaration, instance initializer or static initializer. 1017 * 1018 * @return the immediately enclosing method of the underlying class, if 1019 * that class is a local or anonymous class; otherwise {@code null}. 1020 * 1021 * @throws SecurityException 1022 * If a security manager, <i>s</i>, is present and any of the 1023 * following conditions is met: 1024 * 1025 * <ul> 1026 * 1027 * <li> the caller's class loader is not the same as the 1028 * class loader of the enclosing class and invocation of 1029 * {@link SecurityManager#checkPermission 1030 * s.checkPermission} method with 1031 * {@code RuntimePermission("accessDeclaredMembers")} 1032 * denies access to the methods within the enclosing class 1033 * 1034 * <li> the caller's class loader is not the same as or an 1035 * ancestor of the class loader for the enclosing class and 1036 * invocation of {@link SecurityManager#checkPackageAccess 1037 * s.checkPackageAccess()} denies access to the package 1038 * of the enclosing class 1039 * 1040 * </ul> 1041 * @since 1.5 1042 */ 1043 @CallerSensitive 1044 public Method getEnclosingMethod() throws SecurityException { 1045 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo(); 1046 1047 if (enclosingInfo == null) 1048 return null; 1049 else { 1050 if (!enclosingInfo.isMethod()) 1051 return null; 1052 1053 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(), 1054 getFactory()); 1055 Class<?> returnType = toClass(typeInfo.getReturnType()); 1056 Type [] parameterTypes = typeInfo.getParameterTypes(); 1057 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length]; 1058 1059 // Convert Types to Classes; returned types *should* 1060 // be class objects since the methodDescriptor's used 1061 // don't have generics information 1062 for(int i = 0; i < parameterClasses.length; i++) 1063 parameterClasses[i] = toClass(parameterTypes[i]); 1064 1065 // Perform access check 1066 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass(); 1067 enclosingCandidate.checkMemberAccess(Member.DECLARED, 1068 Reflection.getCallerClass(), true); 1069 // Client is ok to access declared methods but j.l.Class might not be. 1070 Method[] candidates = AccessController.doPrivileged( 1071 new PrivilegedAction<Method[]>() { 1072 @Override 1073 public Method[] run() { 1074 return enclosingCandidate.getDeclaredMethods(); 1075 } 1076 }); 1077 /* 1078 * Loop over all declared methods; match method name, 1079 * number of and type of parameters, *and* return 1080 * type. Matching return type is also necessary 1081 * because of covariant returns, etc. 1082 */ 1083 for(Method m: candidates) { 1084 if (m.getName().equals(enclosingInfo.getName()) ) { 1085 Class<?>[] candidateParamClasses = m.getParameterTypes(); 1086 if (candidateParamClasses.length == parameterClasses.length) { 1087 boolean matches = true; 1088 for(int i = 0; i < candidateParamClasses.length; i++) { 1089 if (!candidateParamClasses[i].equals(parameterClasses[i])) { 1090 matches = false; 1091 break; 1092 } 1093 } 1094 1095 if (matches) { // finally, check return type 1096 if (m.getReturnType().equals(returnType) ) 1097 return m; 1098 } 1099 } 1100 } 1101 } 1102 1103 throw new InternalError("Enclosing method not found"); 1104 } 1105 } 1106 1107 private native Object[] getEnclosingMethod0(); 1108 1109 private EnclosingMethodInfo getEnclosingMethodInfo() { 1110 Object[] enclosingInfo = getEnclosingMethod0(); 1111 if (enclosingInfo == null) 1112 return null; 1113 else { 1114 return new EnclosingMethodInfo(enclosingInfo); 1115 } 1116 } 1117 1118 private final static class EnclosingMethodInfo { 1119 private Class<?> enclosingClass; 1120 private String name; 1121 private String descriptor; 1122 1123 private EnclosingMethodInfo(Object[] enclosingInfo) { 1124 if (enclosingInfo.length != 3) 1125 throw new InternalError("Malformed enclosing method information"); 1126 try { 1127 // The array is expected to have three elements: 1128 1129 // the immediately enclosing class 1130 enclosingClass = (Class<?>) enclosingInfo[0]; 1131 assert(enclosingClass != null); 1132 1133 // the immediately enclosing method or constructor's 1134 // name (can be null). 1135 name = (String) enclosingInfo[1]; 1136 1137 // the immediately enclosing method or constructor's 1138 // descriptor (null iff name is). 1139 descriptor = (String) enclosingInfo[2]; 1140 assert((name != null && descriptor != null) || name == descriptor); 1141 } catch (ClassCastException cce) { 1142 throw new InternalError("Invalid type in enclosing method information", cce); 1143 } 1144 } 1145 1146 boolean isPartial() { 1147 return enclosingClass == null || name == null || descriptor == null; 1148 } 1149 1150 boolean isConstructor() { return !isPartial() && "<init>".equals(name); } 1151 1152 boolean isMethod() { return !isPartial() && !isConstructor() && !"<clinit>".equals(name); } 1153 1154 Class<?> getEnclosingClass() { return enclosingClass; } 1155 1156 String getName() { return name; } 1157 1158 String getDescriptor() { return descriptor; } 1159 1160 } 1161 1162 private static Class<?> toClass(Type o) { 1163 if (o instanceof GenericArrayType) 1164 return Array.newInstance(toClass(((GenericArrayType)o).getGenericComponentType()), 1165 0) 1166 .getClass(); 1167 return (Class<?>)o; 1168 } 1169 1170 /** 1171 * If this {@code Class} object represents a local or anonymous 1172 * class within a constructor, returns a {@link 1173 * java.lang.reflect.Constructor Constructor} object representing 1174 * the immediately enclosing constructor of the underlying 1175 * class. Returns {@code null} otherwise. In particular, this 1176 * method returns {@code null} if the underlying class is a local 1177 * or anonymous class immediately enclosed by a type declaration, 1178 * instance initializer or static initializer. 1179 * 1180 * @return the immediately enclosing constructor of the underlying class, if 1181 * that class is a local or anonymous class; otherwise {@code null}. 1182 * @throws SecurityException 1183 * If a security manager, <i>s</i>, is present and any of the 1184 * following conditions is met: 1185 * 1186 * <ul> 1187 * 1188 * <li> the caller's class loader is not the same as the 1189 * class loader of the enclosing class and invocation of 1190 * {@link SecurityManager#checkPermission 1191 * s.checkPermission} method with 1192 * {@code RuntimePermission("accessDeclaredMembers")} 1193 * denies access to the constructors within the enclosing class 1194 * 1195 * <li> the caller's class loader is not the same as or an 1196 * ancestor of the class loader for the enclosing class and 1197 * invocation of {@link SecurityManager#checkPackageAccess 1198 * s.checkPackageAccess()} denies access to the package 1199 * of the enclosing class 1200 * 1201 * </ul> 1202 * @since 1.5 1203 */ 1204 @CallerSensitive 1205 public Constructor<?> getEnclosingConstructor() throws SecurityException { 1206 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo(); 1207 1208 if (enclosingInfo == null) 1209 return null; 1210 else { 1211 if (!enclosingInfo.isConstructor()) 1212 return null; 1213 1214 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(), 1215 getFactory()); 1216 Type [] parameterTypes = typeInfo.getParameterTypes(); 1217 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length]; 1218 1219 // Convert Types to Classes; returned types *should* 1220 // be class objects since the methodDescriptor's used 1221 // don't have generics information 1222 for(int i = 0; i < parameterClasses.length; i++) 1223 parameterClasses[i] = toClass(parameterTypes[i]); 1224 1225 // Perform access check 1226 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass(); 1227 enclosingCandidate.checkMemberAccess(Member.DECLARED, 1228 Reflection.getCallerClass(), true); 1229 // Client is ok to access declared methods but j.l.Class might not be. 1230 Constructor<?>[] candidates = AccessController.doPrivileged( 1231 new PrivilegedAction<Constructor<?>[]>() { 1232 @Override 1233 public Constructor<?>[] run() { 1234 return enclosingCandidate.getDeclaredConstructors(); 1235 } 1236 }); 1237 /* 1238 * Loop over all declared constructors; match number 1239 * of and type of parameters. 1240 */ 1241 for(Constructor<?> c: candidates) { 1242 Class<?>[] candidateParamClasses = c.getParameterTypes(); 1243 if (candidateParamClasses.length == parameterClasses.length) { 1244 boolean matches = true; 1245 for(int i = 0; i < candidateParamClasses.length; i++) { 1246 if (!candidateParamClasses[i].equals(parameterClasses[i])) { 1247 matches = false; 1248 break; 1249 } 1250 } 1251 1252 if (matches) 1253 return c; 1254 } 1255 } 1256 1257 throw new InternalError("Enclosing constructor not found"); 1258 } 1259 } 1260 1261 1262 /** 1263 * If the class or interface represented by this {@code Class} object 1264 * is a member of another class, returns the {@code Class} object 1265 * representing the class in which it was declared. This method returns 1266 * null if this class or interface is not a member of any other class. If 1267 * this {@code Class} object represents an array class, a primitive 1268 * type, or void,then this method returns null. 1269 * 1270 * @return the declaring class for this class 1271 * @throws SecurityException 1272 * If a security manager, <i>s</i>, is present and the caller's 1273 * class loader is not the same as or an ancestor of the class 1274 * loader for the declaring class and invocation of {@link 1275 * SecurityManager#checkPackageAccess s.checkPackageAccess()} 1276 * denies access to the package of the declaring class 1277 * @since 1.1 1278 */ 1279 @CallerSensitive 1280 public Class<?> getDeclaringClass() throws SecurityException { 1281 final Class<?> candidate = getDeclaringClass0(); 1282 1283 if (candidate != null) 1284 candidate.checkPackageAccess( 1285 ClassLoader.getClassLoader(Reflection.getCallerClass()), true); 1286 return candidate; 1287 } 1288 1289 private native Class<?> getDeclaringClass0(); 1290 1291 1292 /** 1293 * Returns the immediately enclosing class of the underlying 1294 * class. If the underlying class is a top level class this 1295 * method returns {@code null}. 1296 * @return the immediately enclosing class of the underlying class 1297 * @exception SecurityException 1298 * If a security manager, <i>s</i>, is present and the caller's 1299 * class loader is not the same as or an ancestor of the class 1300 * loader for the enclosing class and invocation of {@link 1301 * SecurityManager#checkPackageAccess s.checkPackageAccess()} 1302 * denies access to the package of the enclosing class 1303 * @since 1.5 1304 */ 1305 @CallerSensitive 1306 public Class<?> getEnclosingClass() throws SecurityException { 1307 // There are five kinds of classes (or interfaces): 1308 // a) Top level classes 1309 // b) Nested classes (static member classes) 1310 // c) Inner classes (non-static member classes) 1311 // d) Local classes (named classes declared within a method) 1312 // e) Anonymous classes 1313 1314 1315 // JVM Spec 4.8.6: A class must have an EnclosingMethod 1316 // attribute if and only if it is a local class or an 1317 // anonymous class. 1318 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo(); 1319 Class<?> enclosingCandidate; 1320 1321 if (enclosingInfo == null) { 1322 // This is a top level or a nested class or an inner class (a, b, or c) 1323 enclosingCandidate = getDeclaringClass(); 1324 } else { 1325 Class<?> enclosingClass = enclosingInfo.getEnclosingClass(); 1326 // This is a local class or an anonymous class (d or e) 1327 if (enclosingClass == this || enclosingClass == null) 1328 throw new InternalError("Malformed enclosing method information"); 1329 else 1330 enclosingCandidate = enclosingClass; 1331 } 1332 1333 if (enclosingCandidate != null) 1334 enclosingCandidate.checkPackageAccess( 1335 ClassLoader.getClassLoader(Reflection.getCallerClass()), true); 1336 return enclosingCandidate; 1337 } 1338 1339 /** 1340 * Returns the simple name of the underlying class as given in the 1341 * source code. Returns an empty string if the underlying class is 1342 * anonymous. 1343 * 1344 * <p>The simple name of an array is the simple name of the 1345 * component type with "[]" appended. In particular the simple 1346 * name of an array whose component type is anonymous is "[]". 1347 * 1348 * @return the simple name of the underlying class 1349 * @since 1.5 1350 */ 1351 public String getSimpleName() { 1352 if (isArray()) 1353 return getComponentType().getSimpleName()+"[]"; 1354 1355 String simpleName = getSimpleBinaryName(); 1356 if (simpleName == null) { // top level class 1357 simpleName = getName(); 1358 return simpleName.substring(simpleName.lastIndexOf('.')+1); // strip the package name 1359 } 1360 // According to JLS3 "Binary Compatibility" (13.1) the binary 1361 // name of non-package classes (not top level) is the binary 1362 // name of the immediately enclosing class followed by a '$' followed by: 1363 // (for nested and inner classes): the simple name. 1364 // (for local classes): 1 or more digits followed by the simple name. 1365 // (for anonymous classes): 1 or more digits. 1366 1367 // Since getSimpleBinaryName() will strip the binary name of 1368 // the immediately enclosing class, we are now looking at a 1369 // string that matches the regular expression "\$[0-9]*" 1370 // followed by a simple name (considering the simple of an 1371 // anonymous class to be the empty string). 1372 1373 // Remove leading "\$[0-9]*" from the name 1374 int length = simpleName.length(); 1375 if (length < 1 || simpleName.charAt(0) != '$') 1376 throw new InternalError("Malformed class name"); 1377 int index = 1; 1378 while (index < length && isAsciiDigit(simpleName.charAt(index))) 1379 index++; 1380 // Eventually, this is the empty string iff this is an anonymous class 1381 return simpleName.substring(index); 1382 } 1383 1384 /** 1385 * Return an informative string for the name of this type. 1386 * 1387 * @return an informative string for the name of this type 1388 * @since 1.8 1389 */ 1390 public String getTypeName() { 1391 if (isArray()) { 1392 try { 1393 Class<?> cl = this; 1394 int dimensions = 0; 1395 while (cl.isArray()) { 1396 dimensions++; 1397 cl = cl.getComponentType(); 1398 } 1399 StringBuilder sb = new StringBuilder(); 1400 sb.append(cl.getName()); 1401 for (int i = 0; i < dimensions; i++) { 1402 sb.append("[]"); 1403 } 1404 return sb.toString(); 1405 } catch (Throwable e) { /*FALLTHRU*/ } 1406 } 1407 return getName(); 1408 } 1409 1410 /** 1411 * Character.isDigit answers {@code true} to some non-ascii 1412 * digits. This one does not. 1413 */ 1414 private static boolean isAsciiDigit(char c) { 1415 return '0' <= c && c <= '9'; 1416 } 1417 1418 /** 1419 * Returns the canonical name of the underlying class as 1420 * defined by the Java Language Specification. Returns null if 1421 * the underlying class does not have a canonical name (i.e., if 1422 * it is a local or anonymous class or an array whose component 1423 * type does not have a canonical name). 1424 * @return the canonical name of the underlying class if it exists, and 1425 * {@code null} otherwise. 1426 * @since 1.5 1427 */ 1428 public String getCanonicalName() { 1429 if (isArray()) { 1430 String canonicalName = getComponentType().getCanonicalName(); 1431 if (canonicalName != null) 1432 return canonicalName + "[]"; 1433 else 1434 return null; 1435 } 1436 if (isLocalOrAnonymousClass()) 1437 return null; 1438 Class<?> enclosingClass = getEnclosingClass(); 1439 if (enclosingClass == null) { // top level class 1440 return getName(); 1441 } else { 1442 String enclosingName = enclosingClass.getCanonicalName(); 1443 if (enclosingName == null) 1444 return null; 1445 return enclosingName + "." + getSimpleName(); 1446 } 1447 } 1448 1449 /** 1450 * Returns {@code true} if and only if the underlying class 1451 * is an anonymous class. 1452 * 1453 * @return {@code true} if and only if this class is an anonymous class. 1454 * @since 1.5 1455 */ 1456 public boolean isAnonymousClass() { 1457 return "".equals(getSimpleName()); 1458 } 1459 1460 /** 1461 * Returns {@code true} if and only if the underlying class 1462 * is a local class. 1463 * 1464 * @return {@code true} if and only if this class is a local class. 1465 * @since 1.5 1466 */ 1467 public boolean isLocalClass() { 1468 return isLocalOrAnonymousClass() && !isAnonymousClass(); 1469 } 1470 1471 /** 1472 * Returns {@code true} if and only if the underlying class 1473 * is a member class. 1474 * 1475 * @return {@code true} if and only if this class is a member class. 1476 * @since 1.5 1477 */ 1478 public boolean isMemberClass() { 1479 return getSimpleBinaryName() != null && !isLocalOrAnonymousClass(); 1480 } 1481 1482 /** 1483 * Returns the "simple binary name" of the underlying class, i.e., 1484 * the binary name without the leading enclosing class name. 1485 * Returns {@code null} if the underlying class is a top level 1486 * class. 1487 */ 1488 private String getSimpleBinaryName() { 1489 Class<?> enclosingClass = getEnclosingClass(); 1490 if (enclosingClass == null) // top level class 1491 return null; 1492 // Otherwise, strip the enclosing class' name 1493 try { 1494 return getName().substring(enclosingClass.getName().length()); 1495 } catch (IndexOutOfBoundsException ex) { 1496 throw new InternalError("Malformed class name", ex); 1497 } 1498 } 1499 1500 /** 1501 * Returns {@code true} if this is a local class or an anonymous 1502 * class. Returns {@code false} otherwise. 1503 */ 1504 private boolean isLocalOrAnonymousClass() { 1505 // JVM Spec 4.8.6: A class must have an EnclosingMethod 1506 // attribute if and only if it is a local class or an 1507 // anonymous class. 1508 return getEnclosingMethodInfo() != null; 1509 } 1510 1511 /** 1512 * Returns an array containing {@code Class} objects representing all 1513 * the public classes and interfaces that are members of the class 1514 * represented by this {@code Class} object. This includes public 1515 * class and interface members inherited from superclasses and public class 1516 * and interface members declared by the class. This method returns an 1517 * array of length 0 if this {@code Class} object has no public member 1518 * classes or interfaces. This method also returns an array of length 0 if 1519 * this {@code Class} object represents a primitive type, an array 1520 * class, or void. 1521 * 1522 * @return the array of {@code Class} objects representing the public 1523 * members of this class 1524 * @throws SecurityException 1525 * If a security manager, <i>s</i>, is present and 1526 * the caller's class loader is not the same as or an 1527 * ancestor of the class loader for the current class and 1528 * invocation of {@link SecurityManager#checkPackageAccess 1529 * s.checkPackageAccess()} denies access to the package 1530 * of this class. 1531 * 1532 * @since 1.1 1533 */ 1534 @CallerSensitive 1535 public Class<?>[] getClasses() { 1536 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), false); 1537 1538 // Privileged so this implementation can look at DECLARED classes, 1539 // something the caller might not have privilege to do. The code here 1540 // is allowed to look at DECLARED classes because (1) it does not hand 1541 // out anything other than public members and (2) public member access 1542 // has already been ok'd by the SecurityManager. 1543 1544 return java.security.AccessController.doPrivileged( 1545 new java.security.PrivilegedAction<Class<?>[]>() { 1546 public Class<?>[] run() { 1547 List<Class<?>> list = new ArrayList<>(); 1548 Class<?> currentClass = Class.this; 1549 while (currentClass != null) { 1550 for (Class<?> m : currentClass.getDeclaredClasses()) { 1551 if (Modifier.isPublic(m.getModifiers())) { 1552 list.add(m); 1553 } 1554 } 1555 currentClass = currentClass.getSuperclass(); 1556 } 1557 return list.toArray(new Class<?>[0]); 1558 } 1559 }); 1560 } 1561 1562 1563 /** 1564 * Returns an array containing {@code Field} objects reflecting all 1565 * the accessible public fields of the class or interface represented by 1566 * this {@code Class} object. 1567 * 1568 * <p> If this {@code Class} object represents a class or interface with 1569 * no accessible public fields, then this method returns an array of length 1570 * 0. 1571 * 1572 * <p> If this {@code Class} object represents a class, then this method 1573 * returns the public fields of the class and of all its superclasses and 1574 * superinterfaces. 1575 * 1576 * <p> If this {@code Class} object represents an interface, then this 1577 * method returns the fields of the interface and of all its 1578 * superinterfaces. 1579 * 1580 * <p> If this {@code Class} object represents an array type, a primitive 1581 * type, or void, then this method returns an array of length 0. 1582 * 1583 * <p> The elements in the returned array are not sorted and are not in any 1584 * particular order. 1585 * 1586 * @return the array of {@code Field} objects representing the 1587 * public fields 1588 * @throws SecurityException 1589 * If a security manager, <i>s</i>, is present and 1590 * the caller's class loader is not the same as or an 1591 * ancestor of the class loader for the current class and 1592 * invocation of {@link SecurityManager#checkPackageAccess 1593 * s.checkPackageAccess()} denies access to the package 1594 * of this class. 1595 * 1596 * @since 1.1 1597 * @jls 8.2 Class Members 1598 * @jls 8.3 Field Declarations 1599 */ 1600 @CallerSensitive 1601 public Field[] getFields() throws SecurityException { 1602 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true); 1603 return copyFields(privateGetPublicFields(null)); 1604 } 1605 1606 1607 /** 1608 * Returns an array containing {@code Method} objects reflecting all the 1609 * public methods of the class or interface represented by this {@code 1610 * Class} object, including those declared by the class or interface and 1611 * those inherited from superclasses and superinterfaces. 1612 * 1613 * <p> If this {@code Class} object represents a type that has multiple 1614 * public methods with the same name and parameter types, but different 1615 * return types, then the returned array has a {@code Method} object for 1616 * each such method. 1617 * 1618 * <p> If this {@code Class} object represents a type with a class 1619 * initialization method {@code <clinit>}, then the returned array does 1620 * <em>not</em> have a corresponding {@code Method} object. 1621 * 1622 * <p> If this {@code Class} object represents an array type, then the 1623 * returned array has a {@code Method} object for each of the public 1624 * methods inherited by the array type from {@code Object}. It does not 1625 * contain a {@code Method} object for {@code clone()}. 1626 * 1627 * <p> If this {@code Class} object represents an interface then the 1628 * returned array does not contain any implicitly declared methods from 1629 * {@code Object}. Therefore, if no methods are explicitly declared in 1630 * this interface or any of its superinterfaces then the returned array 1631 * has length 0. (Note that a {@code Class} object which represents a class 1632 * always has public methods, inherited from {@code Object}.) 1633 * 1634 * <p> If this {@code Class} object represents a primitive type or void, 1635 * then the returned array has length 0. 1636 * 1637 * <p> Static methods declared in superinterfaces of the class or interface 1638 * represented by this {@code Class} object are not considered members of 1639 * the class or interface. 1640 * 1641 * <p> The elements in the returned array are not sorted and are not in any 1642 * particular order. 1643 * 1644 * @return the array of {@code Method} objects representing the 1645 * public methods of this class 1646 * @throws SecurityException 1647 * If a security manager, <i>s</i>, is present and 1648 * the caller's class loader is not the same as or an 1649 * ancestor of the class loader for the current class and 1650 * invocation of {@link SecurityManager#checkPackageAccess 1651 * s.checkPackageAccess()} denies access to the package 1652 * of this class. 1653 * 1654 * @jls 8.2 Class Members 1655 * @jls 8.4 Method Declarations 1656 * @since 1.1 1657 */ 1658 @CallerSensitive 1659 public Method[] getMethods() throws SecurityException { 1660 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true); 1661 return copyMethods(privateGetPublicMethods()); 1662 } 1663 1664 1665 /** 1666 * Returns an array containing {@code Constructor} objects reflecting 1667 * all the public constructors of the class represented by this 1668 * {@code Class} object. An array of length 0 is returned if the 1669 * class has no public constructors, or if the class is an array class, or 1670 * if the class reflects a primitive type or void. 1671 * 1672 * Note that while this method returns an array of {@code 1673 * Constructor<T>} objects (that is an array of constructors from 1674 * this class), the return type of this method is {@code 1675 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as 1676 * might be expected. This less informative return type is 1677 * necessary since after being returned from this method, the 1678 * array could be modified to hold {@code Constructor} objects for 1679 * different classes, which would violate the type guarantees of 1680 * {@code Constructor<T>[]}. 1681 * 1682 * @return the array of {@code Constructor} objects representing the 1683 * public constructors of this class 1684 * @throws SecurityException 1685 * If a security manager, <i>s</i>, is present and 1686 * the caller's class loader is not the same as or an 1687 * ancestor of the class loader for the current class and 1688 * invocation of {@link SecurityManager#checkPackageAccess 1689 * s.checkPackageAccess()} denies access to the package 1690 * of this class. 1691 * 1692 * @since 1.1 1693 */ 1694 @CallerSensitive 1695 public Constructor<?>[] getConstructors() throws SecurityException { 1696 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true); 1697 return copyConstructors(privateGetDeclaredConstructors(true)); 1698 } 1699 1700 1701 /** 1702 * Returns a {@code Field} object that reflects the specified public member 1703 * field of the class or interface represented by this {@code Class} 1704 * object. The {@code name} parameter is a {@code String} specifying the 1705 * simple name of the desired field. 1706 * 1707 * <p> The field to be reflected is determined by the algorithm that 1708 * follows. Let C be the class or interface represented by this object: 1709 * 1710 * <OL> 1711 * <LI> If C declares a public field with the name specified, that is the 1712 * field to be reflected.</LI> 1713 * <LI> If no field was found in step 1 above, this algorithm is applied 1714 * recursively to each direct superinterface of C. The direct 1715 * superinterfaces are searched in the order they were declared.</LI> 1716 * <LI> If no field was found in steps 1 and 2 above, and C has a 1717 * superclass S, then this algorithm is invoked recursively upon S. 1718 * If C has no superclass, then a {@code NoSuchFieldException} 1719 * is thrown.</LI> 1720 * </OL> 1721 * 1722 * <p> If this {@code Class} object represents an array type, then this 1723 * method does not find the {@code length} field of the array type. 1724 * 1725 * @param name the field name 1726 * @return the {@code Field} object of this class specified by 1727 * {@code name} 1728 * @throws NoSuchFieldException if a field with the specified name is 1729 * not found. 1730 * @throws NullPointerException if {@code name} is {@code null} 1731 * @throws SecurityException 1732 * If a security manager, <i>s</i>, is present and 1733 * the caller's class loader is not the same as or an 1734 * ancestor of the class loader for the current class and 1735 * invocation of {@link SecurityManager#checkPackageAccess 1736 * s.checkPackageAccess()} denies access to the package 1737 * of this class. 1738 * 1739 * @since 1.1 1740 * @jls 8.2 Class Members 1741 * @jls 8.3 Field Declarations 1742 */ 1743 @CallerSensitive 1744 public Field getField(String name) 1745 throws NoSuchFieldException, SecurityException { 1746 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true); 1747 Field field = getField0(name); 1748 if (field == null) { 1749 throw new NoSuchFieldException(name); 1750 } 1751 return field; 1752 } 1753 1754 1755 /** 1756 * Returns a {@code Method} object that reflects the specified public 1757 * member method of the class or interface represented by this 1758 * {@code Class} object. The {@code name} parameter is a 1759 * {@code String} specifying the simple name of the desired method. The 1760 * {@code parameterTypes} parameter is an array of {@code Class} 1761 * objects that identify the method's formal parameter types, in declared 1762 * order. If {@code parameterTypes} is {@code null}, it is 1763 * treated as if it were an empty array. 1764 * 1765 * <p> If the {@code name} is "{@code <init>}" or "{@code <clinit>}" a 1766 * {@code NoSuchMethodException} is raised. Otherwise, the method to 1767 * be reflected is determined by the algorithm that follows. Let C be the 1768 * class or interface represented by this object: 1769 * <OL> 1770 * <LI> C is searched for a <I>matching method</I>, as defined below. If a 1771 * matching method is found, it is reflected.</LI> 1772 * <LI> If no matching method is found by step 1 then: 1773 * <OL TYPE="a"> 1774 * <LI> If C is a class other than {@code Object}, then this algorithm is 1775 * invoked recursively on the superclass of C.</LI> 1776 * <LI> If C is the class {@code Object}, or if C is an interface, then 1777 * the superinterfaces of C (if any) are searched for a matching 1778 * method. If any such method is found, it is reflected.</LI> 1779 * </OL></LI> 1780 * </OL> 1781 * 1782 * <p> To find a matching method in a class or interface C: If C 1783 * declares exactly one public method with the specified name and exactly 1784 * the same formal parameter types, that is the method reflected. If more 1785 * than one such method is found in C, and one of these methods has a 1786 * return type that is more specific than any of the others, that method is 1787 * reflected; otherwise one of the methods is chosen arbitrarily. 1788 * 1789 * <p>Note that there may be more than one matching method in a 1790 * class because while the Java language forbids a class to 1791 * declare multiple methods with the same signature but different 1792 * return types, the Java virtual machine does not. This 1793 * increased flexibility in the virtual machine can be used to 1794 * implement various language features. For example, covariant 1795 * returns can be implemented with {@linkplain 1796 * java.lang.reflect.Method#isBridge bridge methods}; the bridge 1797 * method and the method being overridden would have the same 1798 * signature but different return types. 1799 * 1800 * <p> If this {@code Class} object represents an array type, then this 1801 * method does not find the {@code clone()} method. 1802 * 1803 * <p> Static methods declared in superinterfaces of the class or interface 1804 * represented by this {@code Class} object are not considered members of 1805 * the class or interface. 1806 * 1807 * @param name the name of the method 1808 * @param parameterTypes the list of parameters 1809 * @return the {@code Method} object that matches the specified 1810 * {@code name} and {@code parameterTypes} 1811 * @throws NoSuchMethodException if a matching method is not found 1812 * or if the name is "<init>"or "<clinit>". 1813 * @throws NullPointerException if {@code name} is {@code null} 1814 * @throws SecurityException 1815 * If a security manager, <i>s</i>, is present and 1816 * the caller's class loader is not the same as or an 1817 * ancestor of the class loader for the current class and 1818 * invocation of {@link SecurityManager#checkPackageAccess 1819 * s.checkPackageAccess()} denies access to the package 1820 * of this class. 1821 * 1822 * @jls 8.2 Class Members 1823 * @jls 8.4 Method Declarations 1824 * @since 1.1 1825 */ 1826 @CallerSensitive 1827 public Method getMethod(String name, Class<?>... parameterTypes) 1828 throws NoSuchMethodException, SecurityException { 1829 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true); 1830 Method method = getMethod0(name, parameterTypes, true); 1831 if (method == null) { 1832 throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes)); 1833 } 1834 return method; 1835 } 1836 1837 1838 /** 1839 * Returns a {@code Constructor} object that reflects the specified 1840 * public constructor of the class represented by this {@code Class} 1841 * object. The {@code parameterTypes} parameter is an array of 1842 * {@code Class} objects that identify the constructor's formal 1843 * parameter types, in declared order. 1844 * 1845 * If this {@code Class} object represents an inner class 1846 * declared in a non-static context, the formal parameter types 1847 * include the explicit enclosing instance as the first parameter. 1848 * 1849 * <p> The constructor to reflect is the public constructor of the class 1850 * represented by this {@code Class} object whose formal parameter 1851 * types match those specified by {@code parameterTypes}. 1852 * 1853 * @param parameterTypes the parameter array 1854 * @return the {@code Constructor} object of the public constructor that 1855 * matches the specified {@code parameterTypes} 1856 * @throws NoSuchMethodException if a matching method is not found. 1857 * @throws SecurityException 1858 * If a security manager, <i>s</i>, is present and 1859 * the caller's class loader is not the same as or an 1860 * ancestor of the class loader for the current class and 1861 * invocation of {@link SecurityManager#checkPackageAccess 1862 * s.checkPackageAccess()} denies access to the package 1863 * of this class. 1864 * 1865 * @since 1.1 1866 */ 1867 @CallerSensitive 1868 public Constructor<T> getConstructor(Class<?>... parameterTypes) 1869 throws NoSuchMethodException, SecurityException { 1870 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true); 1871 return getConstructor0(parameterTypes, Member.PUBLIC); 1872 } 1873 1874 1875 /** 1876 * Returns an array of {@code Class} objects reflecting all the 1877 * classes and interfaces declared as members of the class represented by 1878 * this {@code Class} object. This includes public, protected, default 1879 * (package) access, and private classes and interfaces declared by the 1880 * class, but excludes inherited classes and interfaces. This method 1881 * returns an array of length 0 if the class declares no classes or 1882 * interfaces as members, or if this {@code Class} object represents a 1883 * primitive type, an array class, or void. 1884 * 1885 * @return the array of {@code Class} objects representing all the 1886 * declared members of this class 1887 * @throws SecurityException 1888 * If a security manager, <i>s</i>, is present and any of the 1889 * following conditions is met: 1890 * 1891 * <ul> 1892 * 1893 * <li> the caller's class loader is not the same as the 1894 * class loader of this class and invocation of 1895 * {@link SecurityManager#checkPermission 1896 * s.checkPermission} method with 1897 * {@code RuntimePermission("accessDeclaredMembers")} 1898 * denies access to the declared classes within this class 1899 * 1900 * <li> the caller's class loader is not the same as or an 1901 * ancestor of the class loader for the current class and 1902 * invocation of {@link SecurityManager#checkPackageAccess 1903 * s.checkPackageAccess()} denies access to the package 1904 * of this class 1905 * 1906 * </ul> 1907 * 1908 * @since 1.1 1909 */ 1910 @CallerSensitive 1911 public Class<?>[] getDeclaredClasses() throws SecurityException { 1912 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), false); 1913 return getDeclaredClasses0(); 1914 } 1915 1916 1917 /** 1918 * Returns an array of {@code Field} objects reflecting all the fields 1919 * declared by the class or interface represented by this 1920 * {@code Class} object. This includes public, protected, default 1921 * (package) access, and private fields, but excludes inherited fields. 1922 * 1923 * <p> If this {@code Class} object represents a class or interface with no 1924 * declared fields, then this method returns an array of length 0. 1925 * 1926 * <p> If this {@code Class} object represents an array type, a primitive 1927 * type, or void, then this method returns an array of length 0. 1928 * 1929 * <p> The elements in the returned array are not sorted and are not in any 1930 * particular order. 1931 * 1932 * @return the array of {@code Field} objects representing all the 1933 * declared fields of this class 1934 * @throws SecurityException 1935 * If a security manager, <i>s</i>, is present and any of the 1936 * following conditions is met: 1937 * 1938 * <ul> 1939 * 1940 * <li> the caller's class loader is not the same as the 1941 * class loader of this class and invocation of 1942 * {@link SecurityManager#checkPermission 1943 * s.checkPermission} method with 1944 * {@code RuntimePermission("accessDeclaredMembers")} 1945 * denies access to the declared fields within this class 1946 * 1947 * <li> the caller's class loader is not the same as or an 1948 * ancestor of the class loader for the current class and 1949 * invocation of {@link SecurityManager#checkPackageAccess 1950 * s.checkPackageAccess()} denies access to the package 1951 * of this class 1952 * 1953 * </ul> 1954 * 1955 * @since 1.1 1956 * @jls 8.2 Class Members 1957 * @jls 8.3 Field Declarations 1958 */ 1959 @CallerSensitive 1960 public Field[] getDeclaredFields() throws SecurityException { 1961 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true); 1962 return copyFields(privateGetDeclaredFields(false)); 1963 } 1964 1965 1966 /** 1967 * 1968 * Returns an array containing {@code Method} objects reflecting all the 1969 * declared methods of the class or interface represented by this {@code 1970 * Class} object, including public, protected, default (package) 1971 * access, and private methods, but excluding inherited methods. 1972 * 1973 * <p> If this {@code Class} object represents a type that has multiple 1974 * declared methods with the same name and parameter types, but different 1975 * return types, then the returned array has a {@code Method} object for 1976 * each such method. 1977 * 1978 * <p> If this {@code Class} object represents a type that has a class 1979 * initialization method {@code <clinit>}, then the returned array does 1980 * <em>not</em> have a corresponding {@code Method} object. 1981 * 1982 * <p> If this {@code Class} object represents a class or interface with no 1983 * declared methods, then the returned array has length 0. 1984 * 1985 * <p> If this {@code Class} object represents an array type, a primitive 1986 * type, or void, then the returned array has length 0. 1987 * 1988 * <p> The elements in the returned array are not sorted and are not in any 1989 * particular order. 1990 * 1991 * @return the array of {@code Method} objects representing all the 1992 * declared methods of this class 1993 * @throws SecurityException 1994 * If a security manager, <i>s</i>, is present and any of the 1995 * following conditions is met: 1996 * 1997 * <ul> 1998 * 1999 * <li> the caller's class loader is not the same as the 2000 * class loader of this class and invocation of 2001 * {@link SecurityManager#checkPermission 2002 * s.checkPermission} method with 2003 * {@code RuntimePermission("accessDeclaredMembers")} 2004 * denies access to the declared methods within this class 2005 * 2006 * <li> the caller's class loader is not the same as or an 2007 * ancestor of the class loader for the current class and 2008 * invocation of {@link SecurityManager#checkPackageAccess 2009 * s.checkPackageAccess()} denies access to the package 2010 * of this class 2011 * 2012 * </ul> 2013 * 2014 * @jls 8.2 Class Members 2015 * @jls 8.4 Method Declarations 2016 * @since 1.1 2017 */ 2018 @CallerSensitive 2019 public Method[] getDeclaredMethods() throws SecurityException { 2020 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true); 2021 return copyMethods(privateGetDeclaredMethods(false)); 2022 } 2023 2024 2025 /** 2026 * Returns an array of {@code Constructor} objects reflecting all the 2027 * constructors declared by the class represented by this 2028 * {@code Class} object. These are public, protected, default 2029 * (package) access, and private constructors. The elements in the array 2030 * returned are not sorted and are not in any particular order. If the 2031 * class has a default constructor, it is included in the returned array. 2032 * This method returns an array of length 0 if this {@code Class} 2033 * object represents an interface, a primitive type, an array class, or 2034 * void. 2035 * 2036 * <p> See <em>The Java Language Specification</em>, section 8.2. 2037 * 2038 * @return the array of {@code Constructor} objects representing all the 2039 * declared constructors of this class 2040 * @throws SecurityException 2041 * If a security manager, <i>s</i>, is present and any of the 2042 * following conditions is met: 2043 * 2044 * <ul> 2045 * 2046 * <li> the caller's class loader is not the same as the 2047 * class loader of this class and invocation of 2048 * {@link SecurityManager#checkPermission 2049 * s.checkPermission} method with 2050 * {@code RuntimePermission("accessDeclaredMembers")} 2051 * denies access to the declared constructors within this class 2052 * 2053 * <li> the caller's class loader is not the same as or an 2054 * ancestor of the class loader for the current class and 2055 * invocation of {@link SecurityManager#checkPackageAccess 2056 * s.checkPackageAccess()} denies access to the package 2057 * of this class 2058 * 2059 * </ul> 2060 * 2061 * @since 1.1 2062 */ 2063 @CallerSensitive 2064 public Constructor<?>[] getDeclaredConstructors() throws SecurityException { 2065 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true); 2066 return copyConstructors(privateGetDeclaredConstructors(false)); 2067 } 2068 2069 2070 /** 2071 * Returns a {@code Field} object that reflects the specified declared 2072 * field of the class or interface represented by this {@code Class} 2073 * object. The {@code name} parameter is a {@code String} that specifies 2074 * the simple name of the desired field. 2075 * 2076 * <p> If this {@code Class} object represents an array type, then this 2077 * method does not find the {@code length} field of the array type. 2078 * 2079 * @param name the name of the field 2080 * @return the {@code Field} object for the specified field in this 2081 * class 2082 * @throws NoSuchFieldException if a field with the specified name is 2083 * not found. 2084 * @throws NullPointerException if {@code name} is {@code null} 2085 * @throws SecurityException 2086 * If a security manager, <i>s</i>, is present and any of the 2087 * following conditions is met: 2088 * 2089 * <ul> 2090 * 2091 * <li> the caller's class loader is not the same as the 2092 * class loader of this class and invocation of 2093 * {@link SecurityManager#checkPermission 2094 * s.checkPermission} method with 2095 * {@code RuntimePermission("accessDeclaredMembers")} 2096 * denies access to the declared field 2097 * 2098 * <li> the caller's class loader is not the same as or an 2099 * ancestor of the class loader for the current class and 2100 * invocation of {@link SecurityManager#checkPackageAccess 2101 * s.checkPackageAccess()} denies access to the package 2102 * of this class 2103 * 2104 * </ul> 2105 * 2106 * @since 1.1 2107 * @jls 8.2 Class Members 2108 * @jls 8.3 Field Declarations 2109 */ 2110 @CallerSensitive 2111 public Field getDeclaredField(String name) 2112 throws NoSuchFieldException, SecurityException { 2113 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true); 2114 Field field = searchFields(privateGetDeclaredFields(false), name); 2115 if (field == null) { 2116 throw new NoSuchFieldException(name); 2117 } 2118 return field; 2119 } 2120 2121 2122 /** 2123 * Returns a {@code Method} object that reflects the specified 2124 * declared method of the class or interface represented by this 2125 * {@code Class} object. The {@code name} parameter is a 2126 * {@code String} that specifies the simple name of the desired 2127 * method, and the {@code parameterTypes} parameter is an array of 2128 * {@code Class} objects that identify the method's formal parameter 2129 * types, in declared order. If more than one method with the same 2130 * parameter types is declared in a class, and one of these methods has a 2131 * return type that is more specific than any of the others, that method is 2132 * returned; otherwise one of the methods is chosen arbitrarily. If the 2133 * name is "<init>"or "<clinit>" a {@code NoSuchMethodException} 2134 * is raised. 2135 * 2136 * <p> If this {@code Class} object represents an array type, then this 2137 * method does not find the {@code clone()} method. 2138 * 2139 * @param name the name of the method 2140 * @param parameterTypes the parameter array 2141 * @return the {@code Method} object for the method of this class 2142 * matching the specified name and parameters 2143 * @throws NoSuchMethodException if a matching method is not found. 2144 * @throws NullPointerException if {@code name} is {@code null} 2145 * @throws SecurityException 2146 * If a security manager, <i>s</i>, is present and any of the 2147 * following conditions is met: 2148 * 2149 * <ul> 2150 * 2151 * <li> the caller's class loader is not the same as the 2152 * class loader of this class and invocation of 2153 * {@link SecurityManager#checkPermission 2154 * s.checkPermission} method with 2155 * {@code RuntimePermission("accessDeclaredMembers")} 2156 * denies access to the declared method 2157 * 2158 * <li> the caller's class loader is not the same as or an 2159 * ancestor of the class loader for the current class and 2160 * invocation of {@link SecurityManager#checkPackageAccess 2161 * s.checkPackageAccess()} denies access to the package 2162 * of this class 2163 * 2164 * </ul> 2165 * 2166 * @jls 8.2 Class Members 2167 * @jls 8.4 Method Declarations 2168 * @since 1.1 2169 */ 2170 @CallerSensitive 2171 public Method getDeclaredMethod(String name, Class<?>... parameterTypes) 2172 throws NoSuchMethodException, SecurityException { 2173 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true); 2174 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes); 2175 if (method == null) { 2176 throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes)); 2177 } 2178 return method; 2179 } 2180 2181 2182 /** 2183 * Returns a {@code Constructor} object that reflects the specified 2184 * constructor of the class or interface represented by this 2185 * {@code Class} object. The {@code parameterTypes} parameter is 2186 * an array of {@code Class} objects that identify the constructor's 2187 * formal parameter types, in declared order. 2188 * 2189 * If this {@code Class} object represents an inner class 2190 * declared in a non-static context, the formal parameter types 2191 * include the explicit enclosing instance as the first parameter. 2192 * 2193 * @param parameterTypes the parameter array 2194 * @return The {@code Constructor} object for the constructor with the 2195 * specified parameter list 2196 * @throws NoSuchMethodException if a matching method is not found. 2197 * @throws SecurityException 2198 * If a security manager, <i>s</i>, is present and any of the 2199 * following conditions is met: 2200 * 2201 * <ul> 2202 * 2203 * <li> the caller's class loader is not the same as the 2204 * class loader of this class and invocation of 2205 * {@link SecurityManager#checkPermission 2206 * s.checkPermission} method with 2207 * {@code RuntimePermission("accessDeclaredMembers")} 2208 * denies access to the declared constructor 2209 * 2210 * <li> the caller's class loader is not the same as or an 2211 * ancestor of the class loader for the current class and 2212 * invocation of {@link SecurityManager#checkPackageAccess 2213 * s.checkPackageAccess()} denies access to the package 2214 * of this class 2215 * 2216 * </ul> 2217 * 2218 * @since 1.1 2219 */ 2220 @CallerSensitive 2221 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes) 2222 throws NoSuchMethodException, SecurityException { 2223 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true); 2224 return getConstructor0(parameterTypes, Member.DECLARED); 2225 } 2226 2227 /** 2228 * Finds a resource with a given name. The rules for searching resources 2229 * associated with a given class are implemented by the defining 2230 * {@linkplain ClassLoader class loader} of the class. This method 2231 * delegates to this object's class loader. If this object was loaded by 2232 * the bootstrap class loader, the method delegates to {@link 2233 * ClassLoader#getSystemResourceAsStream}. 2234 * 2235 * <p> Before delegation, an absolute resource name is constructed from the 2236 * given resource name using this algorithm: 2237 * 2238 * <ul> 2239 * 2240 * <li> If the {@code name} begins with a {@code '/'} 2241 * (<tt>'\u002f'</tt>), then the absolute name of the resource is the 2242 * portion of the {@code name} following the {@code '/'}. 2243 * 2244 * <li> Otherwise, the absolute name is of the following form: 2245 * 2246 * <blockquote> 2247 * {@code modified_package_name/name} 2248 * </blockquote> 2249 * 2250 * <p> Where the {@code modified_package_name} is the package name of this 2251 * object with {@code '/'} substituted for {@code '.'} 2252 * (<tt>'\u002e'</tt>). 2253 * 2254 * </ul> 2255 * 2256 * @param name name of the desired resource 2257 * @return A {@link java.io.InputStream} object or {@code null} if 2258 * no resource with this name is found 2259 * @throws NullPointerException If {@code name} is {@code null} 2260 * @since 1.1 2261 */ 2262 public InputStream getResourceAsStream(String name) { 2263 name = resolveName(name); 2264 ClassLoader cl = getClassLoader0(); 2265 if (cl==null) { 2266 // A system class. 2267 return ClassLoader.getSystemResourceAsStream(name); 2268 } 2269 return cl.getResourceAsStream(name); 2270 } 2271 2272 /** 2273 * Finds a resource with a given name. The rules for searching resources 2274 * associated with a given class are implemented by the defining 2275 * {@linkplain ClassLoader class loader} of the class. This method 2276 * delegates to this object's class loader. If this object was loaded by 2277 * the bootstrap class loader, the method delegates to {@link 2278 * ClassLoader#getSystemResource}. 2279 * 2280 * <p> Before delegation, an absolute resource name is constructed from the 2281 * given resource name using this algorithm: 2282 * 2283 * <ul> 2284 * 2285 * <li> If the {@code name} begins with a {@code '/'} 2286 * (<tt>'\u002f'</tt>), then the absolute name of the resource is the 2287 * portion of the {@code name} following the {@code '/'}. 2288 * 2289 * <li> Otherwise, the absolute name is of the following form: 2290 * 2291 * <blockquote> 2292 * {@code modified_package_name/name} 2293 * </blockquote> 2294 * 2295 * <p> Where the {@code modified_package_name} is the package name of this 2296 * object with {@code '/'} substituted for {@code '.'} 2297 * (<tt>'\u002e'</tt>). 2298 * 2299 * </ul> 2300 * 2301 * @param name name of the desired resource 2302 * @return A {@link java.net.URL} object or {@code null} if no 2303 * resource with this name is found 2304 * @since 1.1 2305 */ 2306 public java.net.URL getResource(String name) { 2307 name = resolveName(name); 2308 ClassLoader cl = getClassLoader0(); 2309 if (cl==null) { 2310 // A system class. 2311 return ClassLoader.getSystemResource(name); 2312 } 2313 return cl.getResource(name); 2314 } 2315 2316 2317 2318 /** protection domain returned when the internal domain is null */ 2319 private static java.security.ProtectionDomain allPermDomain; 2320 2321 2322 /** 2323 * Returns the {@code ProtectionDomain} of this class. If there is a 2324 * security manager installed, this method first calls the security 2325 * manager's {@code checkPermission} method with a 2326 * {@code RuntimePermission("getProtectionDomain")} permission to 2327 * ensure it's ok to get the 2328 * {@code ProtectionDomain}. 2329 * 2330 * @return the ProtectionDomain of this class 2331 * 2332 * @throws SecurityException 2333 * if a security manager exists and its 2334 * {@code checkPermission} method doesn't allow 2335 * getting the ProtectionDomain. 2336 * 2337 * @see java.security.ProtectionDomain 2338 * @see SecurityManager#checkPermission 2339 * @see java.lang.RuntimePermission 2340 * @since 1.2 2341 */ 2342 public java.security.ProtectionDomain getProtectionDomain() { 2343 SecurityManager sm = System.getSecurityManager(); 2344 if (sm != null) { 2345 sm.checkPermission(SecurityConstants.GET_PD_PERMISSION); 2346 } 2347 java.security.ProtectionDomain pd = getProtectionDomain0(); 2348 if (pd == null) { 2349 if (allPermDomain == null) { 2350 java.security.Permissions perms = 2351 new java.security.Permissions(); 2352 perms.add(SecurityConstants.ALL_PERMISSION); 2353 allPermDomain = 2354 new java.security.ProtectionDomain(null, perms); 2355 } 2356 pd = allPermDomain; 2357 } 2358 return pd; 2359 } 2360 2361 2362 /** 2363 * Returns the ProtectionDomain of this class. 2364 */ 2365 private native java.security.ProtectionDomain getProtectionDomain0(); 2366 2367 /* 2368 * Return the Virtual Machine's Class object for the named 2369 * primitive type. 2370 */ 2371 static native Class<?> getPrimitiveClass(String name); 2372 2373 /* 2374 * Check if client is allowed to access members. If access is denied, 2375 * throw a SecurityException. 2376 * 2377 * This method also enforces package access. 2378 * 2379 * <p> Default policy: allow all clients access with normal Java access 2380 * control. 2381 */ 2382 private void checkMemberAccess(int which, Class<?> caller, boolean checkProxyInterfaces) { 2383 final SecurityManager s = System.getSecurityManager(); 2384 if (s != null) { 2385 /* Default policy allows access to all {@link Member#PUBLIC} members, 2386 * as well as access to classes that have the same class loader as the caller. 2387 * In all other cases, it requires RuntimePermission("accessDeclaredMembers") 2388 * permission. 2389 */ 2390 final ClassLoader ccl = ClassLoader.getClassLoader(caller); 2391 final ClassLoader cl = getClassLoader0(); 2392 if (which != Member.PUBLIC) { 2393 if (ccl != cl) { 2394 s.checkPermission(SecurityConstants.CHECK_MEMBER_ACCESS_PERMISSION); 2395 } 2396 } 2397 this.checkPackageAccess(ccl, checkProxyInterfaces); 2398 } 2399 } 2400 2401 /* 2402 * Checks if a client loaded in ClassLoader ccl is allowed to access this 2403 * class under the current package access policy. If access is denied, 2404 * throw a SecurityException. 2405 */ 2406 private void checkPackageAccess(final ClassLoader ccl, boolean checkProxyInterfaces) { 2407 final SecurityManager s = System.getSecurityManager(); 2408 if (s != null) { 2409 final ClassLoader cl = getClassLoader0(); 2410 2411 if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) { 2412 String name = this.getName(); 2413 int i = name.lastIndexOf('.'); 2414 if (i != -1) { 2415 // skip the package access check on a proxy class in default proxy package 2416 String pkg = name.substring(0, i); 2417 if (!Proxy.isProxyClass(this) || ReflectUtil.isNonPublicProxyClass(this)) { 2418 s.checkPackageAccess(pkg); 2419 } 2420 } 2421 } 2422 // check package access on the proxy interfaces 2423 if (checkProxyInterfaces && Proxy.isProxyClass(this)) { 2424 ReflectUtil.checkProxyPackageAccess(ccl, this.getInterfaces()); 2425 } 2426 } 2427 } 2428 2429 /** 2430 * Add a package name prefix if the name is not absolute Remove leading "/" 2431 * if name is absolute 2432 */ 2433 private String resolveName(String name) { 2434 if (name == null) { 2435 return name; 2436 } 2437 if (!name.startsWith("/")) { 2438 Class<?> c = this; 2439 while (c.isArray()) { 2440 c = c.getComponentType(); 2441 } 2442 String baseName = c.getName(); 2443 int index = baseName.lastIndexOf('.'); 2444 if (index != -1) { 2445 name = baseName.substring(0, index).replace('.', '/') 2446 +"/"+name; 2447 } 2448 } else { 2449 name = name.substring(1); 2450 } 2451 return name; 2452 } 2453 2454 /** 2455 * Atomic operations support. 2456 */ 2457 private static class Atomic { 2458 // initialize Unsafe machinery here, since we need to call Class.class instance method 2459 // and have to avoid calling it in the static initializer of the Class class... 2460 private static final Unsafe unsafe = Unsafe.getUnsafe(); 2461 // offset of Class.reflectionData instance field 2462 private static final long reflectionDataOffset; 2463 // offset of Class.annotationType instance field 2464 private static final long annotationTypeOffset; 2465 // offset of Class.annotationData instance field 2466 private static final long annotationDataOffset; 2467 2468 static { 2469 Field[] fields = Class.class.getDeclaredFields0(false); // bypass caches 2470 reflectionDataOffset = objectFieldOffset(fields, "reflectionData"); 2471 annotationTypeOffset = objectFieldOffset(fields, "annotationType"); 2472 annotationDataOffset = objectFieldOffset(fields, "annotationData"); 2473 } 2474 2475 private static long objectFieldOffset(Field[] fields, String fieldName) { 2476 Field field = searchFields(fields, fieldName); 2477 if (field == null) { 2478 throw new Error("No " + fieldName + " field found in java.lang.Class"); 2479 } 2480 return unsafe.objectFieldOffset(field); 2481 } 2482 2483 static <T> boolean casReflectionData(Class<?> clazz, 2484 SoftReference<ReflectionData<T>> oldData, 2485 SoftReference<ReflectionData<T>> newData) { 2486 return unsafe.compareAndSwapObject(clazz, reflectionDataOffset, oldData, newData); 2487 } 2488 2489 static <T> boolean casAnnotationType(Class<?> clazz, 2490 AnnotationType oldType, 2491 AnnotationType newType) { 2492 return unsafe.compareAndSwapObject(clazz, annotationTypeOffset, oldType, newType); 2493 } 2494 2495 static <T> boolean casAnnotationData(Class<?> clazz, 2496 AnnotationData oldData, 2497 AnnotationData newData) { 2498 return unsafe.compareAndSwapObject(clazz, annotationDataOffset, oldData, newData); 2499 } 2500 } 2501 2502 /** 2503 * Reflection support. 2504 */ 2505 2506 // Caches for certain reflective results 2507 private static boolean useCaches = true; 2508 2509 // reflection data that might get invalidated when JVM TI RedefineClasses() is called 2510 private static class ReflectionData<T> { 2511 volatile Field[] declaredFields; 2512 volatile Field[] publicFields; 2513 volatile Method[] declaredMethods; 2514 volatile Method[] publicMethods; 2515 volatile Constructor<T>[] declaredConstructors; 2516 volatile Constructor<T>[] publicConstructors; 2517 // Intermediate results for getFields and getMethods 2518 volatile Field[] declaredPublicFields; 2519 volatile Method[] declaredPublicMethods; 2520 volatile Class<?>[] interfaces; 2521 2522 // Value of classRedefinedCount when we created this ReflectionData instance 2523 final int redefinedCount; 2524 2525 ReflectionData(int redefinedCount) { 2526 this.redefinedCount = redefinedCount; 2527 } 2528 } 2529 2530 private volatile transient SoftReference<ReflectionData<T>> reflectionData; 2531 2532 // Incremented by the VM on each call to JVM TI RedefineClasses() 2533 // that redefines this class or a superclass. 2534 private volatile transient int classRedefinedCount = 0; 2535 2536 // Lazily create and cache ReflectionData 2537 private ReflectionData<T> reflectionData() { 2538 SoftReference<ReflectionData<T>> reflectionData = this.reflectionData; 2539 int classRedefinedCount = this.classRedefinedCount; 2540 ReflectionData<T> rd; 2541 if (useCaches && 2542 reflectionData != null && 2543 (rd = reflectionData.get()) != null && 2544 rd.redefinedCount == classRedefinedCount) { 2545 return rd; 2546 } 2547 // else no SoftReference or cleared SoftReference or stale ReflectionData 2548 // -> create and replace new instance 2549 return newReflectionData(reflectionData, classRedefinedCount); 2550 } 2551 2552 private ReflectionData<T> newReflectionData(SoftReference<ReflectionData<T>> oldReflectionData, 2553 int classRedefinedCount) { 2554 if (!useCaches) return null; 2555 2556 while (true) { 2557 ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount); 2558 // try to CAS it... 2559 if (Atomic.casReflectionData(this, oldReflectionData, new SoftReference<>(rd))) { 2560 return rd; 2561 } 2562 // else retry 2563 oldReflectionData = this.reflectionData; 2564 classRedefinedCount = this.classRedefinedCount; 2565 if (oldReflectionData != null && 2566 (rd = oldReflectionData.get()) != null && 2567 rd.redefinedCount == classRedefinedCount) { 2568 return rd; 2569 } 2570 } 2571 } 2572 2573 // Generic signature handling 2574 private native String getGenericSignature0(); 2575 2576 // Generic info repository; lazily initialized 2577 private volatile transient ClassRepository genericInfo; 2578 2579 // accessor for factory 2580 private GenericsFactory getFactory() { 2581 // create scope and factory 2582 return CoreReflectionFactory.make(this, ClassScope.make(this)); 2583 } 2584 2585 // accessor for generic info repository; 2586 // generic info is lazily initialized 2587 private ClassRepository getGenericInfo() { 2588 ClassRepository genericInfo = this.genericInfo; 2589 if (genericInfo == null) { 2590 String signature = getGenericSignature0(); 2591 if (signature == null) { 2592 genericInfo = ClassRepository.NONE; 2593 } else { 2594 genericInfo = ClassRepository.make(signature, getFactory()); 2595 } 2596 this.genericInfo = genericInfo; 2597 } 2598 return (genericInfo != ClassRepository.NONE) ? genericInfo : null; 2599 } 2600 2601 // Annotations handling 2602 native byte[] getRawAnnotations(); 2603 // Since 1.8 2604 native byte[] getRawTypeAnnotations(); 2605 static byte[] getExecutableTypeAnnotationBytes(Executable ex) { 2606 return getReflectionFactory().getExecutableTypeAnnotationBytes(ex); 2607 } 2608 2609 native ConstantPool getConstantPool(); 2610 2611 // 2612 // 2613 // java.lang.reflect.Field handling 2614 // 2615 // 2616 2617 // Returns an array of "root" fields. These Field objects must NOT 2618 // be propagated to the outside world, but must instead be copied 2619 // via ReflectionFactory.copyField. 2620 private Field[] privateGetDeclaredFields(boolean publicOnly) { 2621 checkInitted(); 2622 Field[] res; 2623 ReflectionData<T> rd = reflectionData(); 2624 if (rd != null) { 2625 res = publicOnly ? rd.declaredPublicFields : rd.declaredFields; 2626 if (res != null) return res; 2627 } 2628 // No cached value available; request value from VM 2629 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly)); 2630 if (rd != null) { 2631 if (publicOnly) { 2632 rd.declaredPublicFields = res; 2633 } else { 2634 rd.declaredFields = res; 2635 } 2636 } 2637 return res; 2638 } 2639 2640 // Returns an array of "root" fields. These Field objects must NOT 2641 // be propagated to the outside world, but must instead be copied 2642 // via ReflectionFactory.copyField. 2643 private Field[] privateGetPublicFields(Set<Class<?>> traversedInterfaces) { 2644 checkInitted(); 2645 Field[] res; 2646 ReflectionData<T> rd = reflectionData(); 2647 if (rd != null) { 2648 res = rd.publicFields; 2649 if (res != null) return res; 2650 } 2651 2652 // No cached value available; compute value recursively. 2653 // Traverse in correct order for getField(). 2654 List<Field> fields = new ArrayList<>(); 2655 if (traversedInterfaces == null) { 2656 traversedInterfaces = new HashSet<>(); 2657 } 2658 2659 // Local fields 2660 Field[] tmp = privateGetDeclaredFields(true); 2661 addAll(fields, tmp); 2662 2663 // Direct superinterfaces, recursively 2664 for (Class<?> c : getInterfaces()) { 2665 if (!traversedInterfaces.contains(c)) { 2666 traversedInterfaces.add(c); 2667 addAll(fields, c.privateGetPublicFields(traversedInterfaces)); 2668 } 2669 } 2670 2671 // Direct superclass, recursively 2672 if (!isInterface()) { 2673 Class<?> c = getSuperclass(); 2674 if (c != null) { 2675 addAll(fields, c.privateGetPublicFields(traversedInterfaces)); 2676 } 2677 } 2678 2679 res = new Field[fields.size()]; 2680 fields.toArray(res); 2681 if (rd != null) { 2682 rd.publicFields = res; 2683 } 2684 return res; 2685 } 2686 2687 private static void addAll(Collection<Field> c, Field[] o) { 2688 for (Field f : o) { 2689 c.add(f); 2690 } 2691 } 2692 2693 2694 // 2695 // 2696 // java.lang.reflect.Constructor handling 2697 // 2698 // 2699 2700 // Returns an array of "root" constructors. These Constructor 2701 // objects must NOT be propagated to the outside world, but must 2702 // instead be copied via ReflectionFactory.copyConstructor. 2703 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) { 2704 checkInitted(); 2705 Constructor<T>[] res; 2706 ReflectionData<T> rd = reflectionData(); 2707 if (rd != null) { 2708 res = publicOnly ? rd.publicConstructors : rd.declaredConstructors; 2709 if (res != null) return res; 2710 } 2711 // No cached value available; request value from VM 2712 if (isInterface()) { 2713 @SuppressWarnings("unchecked") 2714 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0]; 2715 res = temporaryRes; 2716 } else { 2717 res = getDeclaredConstructors0(publicOnly); 2718 } 2719 if (rd != null) { 2720 if (publicOnly) { 2721 rd.publicConstructors = res; 2722 } else { 2723 rd.declaredConstructors = res; 2724 } 2725 } 2726 return res; 2727 } 2728 2729 // 2730 // 2731 // java.lang.reflect.Method handling 2732 // 2733 // 2734 2735 // Returns an array of "root" methods. These Method objects must NOT 2736 // be propagated to the outside world, but must instead be copied 2737 // via ReflectionFactory.copyMethod. 2738 private Method[] privateGetDeclaredMethods(boolean publicOnly) { 2739 checkInitted(); 2740 Method[] res; 2741 ReflectionData<T> rd = reflectionData(); 2742 if (rd != null) { 2743 res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods; 2744 if (res != null) return res; 2745 } 2746 // No cached value available; request value from VM 2747 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly)); 2748 if (rd != null) { 2749 if (publicOnly) { 2750 rd.declaredPublicMethods = res; 2751 } else { 2752 rd.declaredMethods = res; 2753 } 2754 } 2755 return res; 2756 } 2757 2758 static class MethodArray { 2759 // Don't add or remove methods except by add() or remove() calls. 2760 private Method[] methods; 2761 private int length; 2762 private int defaults; 2763 2764 MethodArray() { 2765 this(20); 2766 } 2767 2768 MethodArray(int initialSize) { 2769 if (initialSize < 2) 2770 throw new IllegalArgumentException("Size should be 2 or more"); 2771 2772 methods = new Method[initialSize]; 2773 length = 0; 2774 defaults = 0; 2775 } 2776 2777 boolean hasDefaults() { 2778 return defaults != 0; 2779 } 2780 2781 void add(Method m) { 2782 if (length == methods.length) { 2783 methods = Arrays.copyOf(methods, 2 * methods.length); 2784 } 2785 methods[length++] = m; 2786 2787 if (m != null && m.isDefault()) 2788 defaults++; 2789 } 2790 2791 void addAll(Method[] ma) { 2792 for (Method m : ma) { 2793 add(m); 2794 } 2795 } 2796 2797 void addAll(MethodArray ma) { 2798 for (int i = 0; i < ma.length(); i++) { 2799 add(ma.get(i)); 2800 } 2801 } 2802 2803 void addIfNotPresent(Method newMethod) { 2804 for (int i = 0; i < length; i++) { 2805 Method m = methods[i]; 2806 if (m == newMethod || (m != null && m.equals(newMethod))) { 2807 return; 2808 } 2809 } 2810 add(newMethod); 2811 } 2812 2813 void addAllIfNotPresent(MethodArray newMethods) { 2814 for (int i = 0; i < newMethods.length(); i++) { 2815 Method m = newMethods.get(i); 2816 if (m != null) { 2817 addIfNotPresent(m); 2818 } 2819 } 2820 } 2821 2822 /* Add Methods declared in an interface to this MethodArray. 2823 * Static methods declared in interfaces are not inherited. 2824 */ 2825 void addInterfaceMethods(Method[] methods) { 2826 for (Method candidate : methods) { 2827 if (!Modifier.isStatic(candidate.getModifiers())) { 2828 add(candidate); 2829 } 2830 } 2831 } 2832 2833 int length() { 2834 return length; 2835 } 2836 2837 Method get(int i) { 2838 return methods[i]; 2839 } 2840 2841 Method getFirst() { 2842 for (Method m : methods) 2843 if (m != null) 2844 return m; 2845 return null; 2846 } 2847 2848 void removeByNameAndDescriptor(Method toRemove) { 2849 for (int i = 0; i < length; i++) { 2850 Method m = methods[i]; 2851 if (m != null && matchesNameAndDescriptor(m, toRemove)) { 2852 remove(i); 2853 } 2854 } 2855 } 2856 2857 private void remove(int i) { 2858 if (methods[i] != null && methods[i].isDefault()) 2859 defaults--; 2860 methods[i] = null; 2861 } 2862 2863 private boolean matchesNameAndDescriptor(Method m1, Method m2) { 2864 return m1.getReturnType() == m2.getReturnType() && 2865 m1.getName() == m2.getName() && // name is guaranteed to be interned 2866 arrayContentsEq(m1.getParameterTypes(), 2867 m2.getParameterTypes()); 2868 } 2869 2870 void compactAndTrim() { 2871 int newPos = 0; 2872 // Get rid of null slots 2873 for (int pos = 0; pos < length; pos++) { 2874 Method m = methods[pos]; 2875 if (m != null) { 2876 if (pos != newPos) { 2877 methods[newPos] = m; 2878 } 2879 newPos++; 2880 } 2881 } 2882 if (newPos != methods.length) { 2883 methods = Arrays.copyOf(methods, newPos); 2884 } 2885 } 2886 2887 /* Removes all Methods from this MethodArray that have a more specific 2888 * default Method in this MethodArray. 2889 * 2890 * Users of MethodArray are responsible for pruning Methods that have 2891 * a more specific <em>concrete</em> Method. 2892 */ 2893 void removeLessSpecifics() { 2894 if (!hasDefaults()) 2895 return; 2896 2897 for (int i = 0; i < length; i++) { 2898 Method m = get(i); 2899 if (m == null || !m.isDefault()) 2900 continue; 2901 2902 for (int j = 0; j < length; j++) { 2903 if (i == j) 2904 continue; 2905 2906 Method candidate = get(j); 2907 if (candidate == null) 2908 continue; 2909 2910 if (!matchesNameAndDescriptor(m, candidate)) 2911 continue; 2912 2913 if (hasMoreSpecificClass(m, candidate)) 2914 remove(j); 2915 } 2916 } 2917 } 2918 2919 Method[] getArray() { 2920 return methods; 2921 } 2922 2923 // Returns true if m1 is more specific than m2 2924 static boolean hasMoreSpecificClass(Method m1, Method m2) { 2925 Class<?> m1Class = m1.getDeclaringClass(); 2926 Class<?> m2Class = m2.getDeclaringClass(); 2927 return m1Class != m2Class && m2Class.isAssignableFrom(m1Class); 2928 } 2929 } 2930 2931 2932 // Returns an array of "root" methods. These Method objects must NOT 2933 // be propagated to the outside world, but must instead be copied 2934 // via ReflectionFactory.copyMethod. 2935 private Method[] privateGetPublicMethods() { 2936 checkInitted(); 2937 Method[] res; 2938 ReflectionData<T> rd = reflectionData(); 2939 if (rd != null) { 2940 res = rd.publicMethods; 2941 if (res != null) return res; 2942 } 2943 2944 // No cached value available; compute value recursively. 2945 // Start by fetching public declared methods 2946 MethodArray methods = new MethodArray(); 2947 { 2948 Method[] tmp = privateGetDeclaredMethods(true); 2949 methods.addAll(tmp); 2950 } 2951 // Now recur over superclass and direct superinterfaces. 2952 // Go over superinterfaces first so we can more easily filter 2953 // out concrete implementations inherited from superclasses at 2954 // the end. 2955 MethodArray inheritedMethods = new MethodArray(); 2956 for (Class<?> i : getInterfaces()) { 2957 inheritedMethods.addInterfaceMethods(i.privateGetPublicMethods()); 2958 } 2959 if (!isInterface()) { 2960 Class<?> c = getSuperclass(); 2961 if (c != null) { 2962 MethodArray supers = new MethodArray(); 2963 supers.addAll(c.privateGetPublicMethods()); 2964 // Filter out concrete implementations of any 2965 // interface methods 2966 for (int i = 0; i < supers.length(); i++) { 2967 Method m = supers.get(i); 2968 if (m != null && 2969 !Modifier.isAbstract(m.getModifiers()) && 2970 !m.isDefault()) { 2971 inheritedMethods.removeByNameAndDescriptor(m); 2972 } 2973 } 2974 // Insert superclass's inherited methods before 2975 // superinterfaces' to satisfy getMethod's search 2976 // order 2977 supers.addAll(inheritedMethods); 2978 inheritedMethods = supers; 2979 } 2980 } 2981 // Filter out all local methods from inherited ones 2982 for (int i = 0; i < methods.length(); i++) { 2983 Method m = methods.get(i); 2984 inheritedMethods.removeByNameAndDescriptor(m); 2985 } 2986 methods.addAllIfNotPresent(inheritedMethods); 2987 methods.removeLessSpecifics(); 2988 methods.compactAndTrim(); 2989 res = methods.getArray(); 2990 if (rd != null) { 2991 rd.publicMethods = res; 2992 } 2993 return res; 2994 } 2995 2996 2997 // 2998 // Helpers for fetchers of one field, method, or constructor 2999 // 3000 3001 private static Field searchFields(Field[] fields, String name) { 3002 String internedName = name.intern(); 3003 for (Field field : fields) { 3004 if (field.getName() == internedName) { 3005 return getReflectionFactory().copyField(field); 3006 } 3007 } 3008 return null; 3009 } 3010 3011 private Field getField0(String name) throws NoSuchFieldException { 3012 // Note: the intent is that the search algorithm this routine 3013 // uses be equivalent to the ordering imposed by 3014 // privateGetPublicFields(). It fetches only the declared 3015 // public fields for each class, however, to reduce the number 3016 // of Field objects which have to be created for the common 3017 // case where the field being requested is declared in the 3018 // class which is being queried. 3019 Field res; 3020 // Search declared public fields 3021 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) { 3022 return res; 3023 } 3024 // Direct superinterfaces, recursively 3025 Class<?>[] interfaces = getInterfaces(); 3026 for (Class<?> c : interfaces) { 3027 if ((res = c.getField0(name)) != null) { 3028 return res; 3029 } 3030 } 3031 // Direct superclass, recursively 3032 if (!isInterface()) { 3033 Class<?> c = getSuperclass(); 3034 if (c != null) { 3035 if ((res = c.getField0(name)) != null) { 3036 return res; 3037 } 3038 } 3039 } 3040 return null; 3041 } 3042 3043 private static Method searchMethods(Method[] methods, 3044 String name, 3045 Class<?>[] parameterTypes) 3046 { 3047 Method res = null; 3048 String internedName = name.intern(); 3049 for (Method m : methods) { 3050 if (m.getName() == internedName 3051 && arrayContentsEq(parameterTypes, m.getParameterTypes()) 3052 && (res == null 3053 || res.getReturnType().isAssignableFrom(m.getReturnType()))) 3054 res = m; 3055 } 3056 3057 return (res == null ? res : getReflectionFactory().copyMethod(res)); 3058 } 3059 3060 private Method getMethod0(String name, Class<?>[] parameterTypes, boolean includeStaticMethods) { 3061 MethodArray interfaceCandidates = new MethodArray(2); 3062 Method res = privateGetMethodRecursive(name, parameterTypes, includeStaticMethods, interfaceCandidates); 3063 if (res != null) 3064 return res; 3065 3066 // Not found on class or superclass directly 3067 interfaceCandidates.removeLessSpecifics(); 3068 return interfaceCandidates.getFirst(); // may be null 3069 } 3070 3071 private Method privateGetMethodRecursive(String name, 3072 Class<?>[] parameterTypes, 3073 boolean includeStaticMethods, 3074 MethodArray allInterfaceCandidates) { 3075 // Note: the intent is that the search algorithm this routine 3076 // uses be equivalent to the ordering imposed by 3077 // privateGetPublicMethods(). It fetches only the declared 3078 // public methods for each class, however, to reduce the 3079 // number of Method objects which have to be created for the 3080 // common case where the method being requested is declared in 3081 // the class which is being queried. 3082 // 3083 // Due to default methods, unless a method is found on a superclass, 3084 // methods declared in any superinterface needs to be considered. 3085 // Collect all candidates declared in superinterfaces in {@code 3086 // allInterfaceCandidates} and select the most specific if no match on 3087 // a superclass is found. 3088 3089 // Must _not_ return root methods 3090 Method res; 3091 // Search declared public methods 3092 if ((res = searchMethods(privateGetDeclaredMethods(true), 3093 name, 3094 parameterTypes)) != null) { 3095 if (includeStaticMethods || !Modifier.isStatic(res.getModifiers())) 3096 return res; 3097 } 3098 // Search superclass's methods 3099 if (!isInterface()) { 3100 Class<? super T> c = getSuperclass(); 3101 if (c != null) { 3102 if ((res = c.getMethod0(name, parameterTypes, true)) != null) { 3103 return res; 3104 } 3105 } 3106 } 3107 // Search superinterfaces' methods 3108 Class<?>[] interfaces = getInterfaces(); 3109 for (Class<?> c : interfaces) 3110 if ((res = c.getMethod0(name, parameterTypes, false)) != null) 3111 allInterfaceCandidates.add(res); 3112 // Not found 3113 return null; 3114 } 3115 3116 private Constructor<T> getConstructor0(Class<?>[] parameterTypes, 3117 int which) throws NoSuchMethodException 3118 { 3119 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC)); 3120 for (Constructor<T> constructor : constructors) { 3121 if (arrayContentsEq(parameterTypes, 3122 constructor.getParameterTypes())) { 3123 return getReflectionFactory().copyConstructor(constructor); 3124 } 3125 } 3126 throw new NoSuchMethodException(getName() + ".<init>" + argumentTypesToString(parameterTypes)); 3127 } 3128 3129 // 3130 // Other helpers and base implementation 3131 // 3132 3133 private static boolean arrayContentsEq(Object[] a1, Object[] a2) { 3134 if (a1 == null) { 3135 return a2 == null || a2.length == 0; 3136 } 3137 3138 if (a2 == null) { 3139 return a1.length == 0; 3140 } 3141 3142 if (a1.length != a2.length) { 3143 return false; 3144 } 3145 3146 for (int i = 0; i < a1.length; i++) { 3147 if (a1[i] != a2[i]) { 3148 return false; 3149 } 3150 } 3151 3152 return true; 3153 } 3154 3155 private static Field[] copyFields(Field[] arg) { 3156 Field[] out = new Field[arg.length]; 3157 ReflectionFactory fact = getReflectionFactory(); 3158 for (int i = 0; i < arg.length; i++) { 3159 out[i] = fact.copyField(arg[i]); 3160 } 3161 return out; 3162 } 3163 3164 private static Method[] copyMethods(Method[] arg) { 3165 Method[] out = new Method[arg.length]; 3166 ReflectionFactory fact = getReflectionFactory(); 3167 for (int i = 0; i < arg.length; i++) { 3168 out[i] = fact.copyMethod(arg[i]); 3169 } 3170 return out; 3171 } 3172 3173 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) { 3174 Constructor<U>[] out = arg.clone(); 3175 ReflectionFactory fact = getReflectionFactory(); 3176 for (int i = 0; i < out.length; i++) { 3177 out[i] = fact.copyConstructor(out[i]); 3178 } 3179 return out; 3180 } 3181 3182 private native Field[] getDeclaredFields0(boolean publicOnly); 3183 private native Method[] getDeclaredMethods0(boolean publicOnly); 3184 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly); 3185 private native Class<?>[] getDeclaredClasses0(); 3186 3187 private static String argumentTypesToString(Class<?>[] argTypes) { 3188 StringJoiner sj = new StringJoiner(", ", "(", ")"); 3189 if (argTypes != null) { 3190 for (int i = 0; i < argTypes.length; i++) { 3191 Class<?> c = argTypes[i]; 3192 sj.add((c == null) ? "null" : c.getName()); 3193 } 3194 } 3195 return sj.toString(); 3196 } 3197 3198 /** use serialVersionUID from JDK 1.1 for interoperability */ 3199 private static final long serialVersionUID = 3206093459760846163L; 3200 3201 3202 /** 3203 * Class Class is special cased within the Serialization Stream Protocol. 3204 * 3205 * A Class instance is written initially into an ObjectOutputStream in the 3206 * following format: 3207 * <pre> 3208 * {@code TC_CLASS} ClassDescriptor 3209 * A ClassDescriptor is a special cased serialization of 3210 * a {@code java.io.ObjectStreamClass} instance. 3211 * </pre> 3212 * A new handle is generated for the initial time the class descriptor 3213 * is written into the stream. Future references to the class descriptor 3214 * are written as references to the initial class descriptor instance. 3215 * 3216 * @see java.io.ObjectStreamClass 3217 */ 3218 private static final ObjectStreamField[] serialPersistentFields = 3219 new ObjectStreamField[0]; 3220 3221 3222 /** 3223 * Returns the assertion status that would be assigned to this 3224 * class if it were to be initialized at the time this method is invoked. 3225 * If this class has had its assertion status set, the most recent 3226 * setting will be returned; otherwise, if any package default assertion 3227 * status pertains to this class, the most recent setting for the most 3228 * specific pertinent package default assertion status is returned; 3229 * otherwise, if this class is not a system class (i.e., it has a 3230 * class loader) its class loader's default assertion status is returned; 3231 * otherwise, the system class default assertion status is returned. 3232 * <p> 3233 * Few programmers will have any need for this method; it is provided 3234 * for the benefit of the JRE itself. (It allows a class to determine at 3235 * the time that it is initialized whether assertions should be enabled.) 3236 * Note that this method is not guaranteed to return the actual 3237 * assertion status that was (or will be) associated with the specified 3238 * class when it was (or will be) initialized. 3239 * 3240 * @return the desired assertion status of the specified class. 3241 * @see java.lang.ClassLoader#setClassAssertionStatus 3242 * @see java.lang.ClassLoader#setPackageAssertionStatus 3243 * @see java.lang.ClassLoader#setDefaultAssertionStatus 3244 * @since 1.4 3245 */ 3246 public boolean desiredAssertionStatus() { 3247 ClassLoader loader = getClassLoader(); 3248 // If the loader is null this is a system class, so ask the VM 3249 if (loader == null) 3250 return desiredAssertionStatus0(this); 3251 3252 // If the classloader has been initialized with the assertion 3253 // directives, ask it. Otherwise, ask the VM. 3254 synchronized(loader.assertionLock) { 3255 if (loader.classAssertionStatus != null) { 3256 return loader.desiredAssertionStatus(getName()); 3257 } 3258 } 3259 return desiredAssertionStatus0(this); 3260 } 3261 3262 // Retrieves the desired assertion status of this class from the VM 3263 private static native boolean desiredAssertionStatus0(Class<?> clazz); 3264 3265 /** 3266 * Returns true if and only if this class was declared as an enum in the 3267 * source code. 3268 * 3269 * @return true if and only if this class was declared as an enum in the 3270 * source code 3271 * @since 1.5 3272 */ 3273 public boolean isEnum() { 3274 // An enum must both directly extend java.lang.Enum and have 3275 // the ENUM bit set; classes for specialized enum constants 3276 // don't do the former. 3277 return (this.getModifiers() & ENUM) != 0 && 3278 this.getSuperclass() == java.lang.Enum.class; 3279 } 3280 3281 // Fetches the factory for reflective objects 3282 private static ReflectionFactory getReflectionFactory() { 3283 if (reflectionFactory == null) { 3284 reflectionFactory = 3285 java.security.AccessController.doPrivileged 3286 (new sun.reflect.ReflectionFactory.GetReflectionFactoryAction()); 3287 } 3288 return reflectionFactory; 3289 } 3290 private static ReflectionFactory reflectionFactory; 3291 3292 // To be able to query system properties as soon as they're available 3293 private static boolean initted = false; 3294 private static void checkInitted() { 3295 if (initted) return; 3296 AccessController.doPrivileged(new PrivilegedAction<Void>() { 3297 public Void run() { 3298 // Tests to ensure the system properties table is fully 3299 // initialized. This is needed because reflection code is 3300 // called very early in the initialization process (before 3301 // command-line arguments have been parsed and therefore 3302 // these user-settable properties installed.) We assume that 3303 // if System.out is non-null then the System class has been 3304 // fully initialized and that the bulk of the startup code 3305 // has been run. 3306 3307 if (System.out == null) { 3308 // java.lang.System not yet fully initialized 3309 return null; 3310 } 3311 3312 // Doesn't use Boolean.getBoolean to avoid class init. 3313 String val = 3314 System.getProperty("sun.reflect.noCaches"); 3315 if (val != null && val.equals("true")) { 3316 useCaches = false; 3317 } 3318 3319 initted = true; 3320 return null; 3321 } 3322 }); 3323 } 3324 3325 /** 3326 * Returns the elements of this enum class or null if this 3327 * Class object does not represent an enum type. 3328 * 3329 * @return an array containing the values comprising the enum class 3330 * represented by this Class object in the order they're 3331 * declared, or null if this Class object does not 3332 * represent an enum type 3333 * @since 1.5 3334 */ 3335 public T[] getEnumConstants() { 3336 T[] values = getEnumConstantsShared(); 3337 return (values != null) ? values.clone() : null; 3338 } 3339 3340 /** 3341 * Returns the elements of this enum class or null if this 3342 * Class object does not represent an enum type; 3343 * identical to getEnumConstants except that the result is 3344 * uncloned, cached, and shared by all callers. 3345 */ 3346 T[] getEnumConstantsShared() { 3347 if (enumConstants == null) { 3348 if (!isEnum()) return null; 3349 try { 3350 final Method values = getMethod("values"); 3351 java.security.AccessController.doPrivileged( 3352 new java.security.PrivilegedAction<Void>() { 3353 public Void run() { 3354 values.setAccessible(true); 3355 return null; 3356 } 3357 }); 3358 @SuppressWarnings("unchecked") 3359 T[] temporaryConstants = (T[])values.invoke(null); 3360 enumConstants = temporaryConstants; 3361 } 3362 // These can happen when users concoct enum-like classes 3363 // that don't comply with the enum spec. 3364 catch (InvocationTargetException | NoSuchMethodException | 3365 IllegalAccessException ex) { return null; } 3366 } 3367 return enumConstants; 3368 } 3369 private volatile transient T[] enumConstants = null; 3370 3371 /** 3372 * Returns a map from simple name to enum constant. This package-private 3373 * method is used internally by Enum to implement 3374 * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)} 3375 * efficiently. Note that the map is returned by this method is 3376 * created lazily on first use. Typically it won't ever get created. 3377 */ 3378 Map<String, T> enumConstantDirectory() { 3379 if (enumConstantDirectory == null) { 3380 T[] universe = getEnumConstantsShared(); 3381 if (universe == null) 3382 throw new IllegalArgumentException( 3383 getName() + " is not an enum type"); 3384 Map<String, T> m = new HashMap<>(2 * universe.length); 3385 for (T constant : universe) 3386 m.put(((Enum<?>)constant).name(), constant); 3387 enumConstantDirectory = m; 3388 } 3389 return enumConstantDirectory; 3390 } 3391 private volatile transient Map<String, T> enumConstantDirectory = null; 3392 3393 /** 3394 * Casts an object to the class or interface represented 3395 * by this {@code Class} object. 3396 * 3397 * @param obj the object to be cast 3398 * @return the object after casting, or null if obj is null 3399 * 3400 * @throws ClassCastException if the object is not 3401 * null and is not assignable to the type T. 3402 * 3403 * @since 1.5 3404 */ 3405 @SuppressWarnings("unchecked") 3406 public T cast(Object obj) { 3407 if (obj != null && !isInstance(obj)) 3408 throw new ClassCastException(cannotCastMsg(obj)); 3409 return (T) obj; 3410 } 3411 3412 private String cannotCastMsg(Object obj) { 3413 return "Cannot cast " + obj.getClass().getName() + " to " + getName(); 3414 } 3415 3416 /** 3417 * Casts this {@code Class} object to represent a subclass of the class 3418 * represented by the specified class object. Checks that the cast 3419 * is valid, and throws a {@code ClassCastException} if it is not. If 3420 * this method succeeds, it always returns a reference to this class object. 3421 * 3422 * <p>This method is useful when a client needs to "narrow" the type of 3423 * a {@code Class} object to pass it to an API that restricts the 3424 * {@code Class} objects that it is willing to accept. A cast would 3425 * generate a compile-time warning, as the correctness of the cast 3426 * could not be checked at runtime (because generic types are implemented 3427 * by erasure). 3428 * 3429 * @param <U> the type to cast this class object to 3430 * @param clazz the class of the type to cast this class object to 3431 * @return this {@code Class} object, cast to represent a subclass of 3432 * the specified class object. 3433 * @throws ClassCastException if this {@code Class} object does not 3434 * represent a subclass of the specified class (here "subclass" includes 3435 * the class itself). 3436 * @since 1.5 3437 */ 3438 @SuppressWarnings("unchecked") 3439 public <U> Class<? extends U> asSubclass(Class<U> clazz) { 3440 if (clazz.isAssignableFrom(this)) 3441 return (Class<? extends U>) this; 3442 else 3443 throw new ClassCastException(this.toString()); 3444 } 3445 3446 /** 3447 * @throws NullPointerException {@inheritDoc} 3448 * @since 1.5 3449 */ 3450 @SuppressWarnings("unchecked") 3451 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) { 3452 Objects.requireNonNull(annotationClass); 3453 3454 return (A) annotationData().annotations.get(annotationClass); 3455 } 3456 3457 /** 3458 * {@inheritDoc} 3459 * @throws NullPointerException {@inheritDoc} 3460 * @since 1.5 3461 */ 3462 @Override 3463 public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) { 3464 return GenericDeclaration.super.isAnnotationPresent(annotationClass); 3465 } 3466 3467 /** 3468 * @throws NullPointerException {@inheritDoc} 3469 * @since 1.8 3470 */ 3471 @Override 3472 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) { 3473 Objects.requireNonNull(annotationClass); 3474 3475 AnnotationData annotationData = annotationData(); 3476 return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations, 3477 this, 3478 annotationClass); 3479 } 3480 3481 /** 3482 * @since 1.5 3483 */ 3484 public Annotation[] getAnnotations() { 3485 return AnnotationParser.toArray(annotationData().annotations); 3486 } 3487 3488 /** 3489 * @throws NullPointerException {@inheritDoc} 3490 * @since 1.8 3491 */ 3492 @Override 3493 @SuppressWarnings("unchecked") 3494 public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) { 3495 Objects.requireNonNull(annotationClass); 3496 3497 return (A) annotationData().declaredAnnotations.get(annotationClass); 3498 } 3499 3500 /** 3501 * @throws NullPointerException {@inheritDoc} 3502 * @since 1.8 3503 */ 3504 @Override 3505 public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) { 3506 Objects.requireNonNull(annotationClass); 3507 3508 return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations, 3509 annotationClass); 3510 } 3511 3512 /** 3513 * @since 1.5 3514 */ 3515 public Annotation[] getDeclaredAnnotations() { 3516 return AnnotationParser.toArray(annotationData().declaredAnnotations); 3517 } 3518 3519 // annotation data that might get invalidated when JVM TI RedefineClasses() is called 3520 private static class AnnotationData { 3521 final Map<Class<? extends Annotation>, Annotation> annotations; 3522 final Map<Class<? extends Annotation>, Annotation> declaredAnnotations; 3523 3524 // Value of classRedefinedCount when we created this AnnotationData instance 3525 final int redefinedCount; 3526 3527 AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations, 3528 Map<Class<? extends Annotation>, Annotation> declaredAnnotations, 3529 int redefinedCount) { 3530 this.annotations = annotations; 3531 this.declaredAnnotations = declaredAnnotations; 3532 this.redefinedCount = redefinedCount; 3533 } 3534 } 3535 3536 // Annotations cache 3537 @SuppressWarnings("UnusedDeclaration") 3538 private volatile transient AnnotationData annotationData; 3539 3540 private AnnotationData annotationData() { 3541 while (true) { // retry loop 3542 AnnotationData annotationData = this.annotationData; 3543 int classRedefinedCount = this.classRedefinedCount; 3544 if (annotationData != null && 3545 annotationData.redefinedCount == classRedefinedCount) { 3546 return annotationData; 3547 } 3548 // null or stale annotationData -> optimistically create new instance 3549 AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount); 3550 // try to install it 3551 if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) { 3552 // successfully installed new AnnotationData 3553 return newAnnotationData; 3554 } 3555 } 3556 } 3557 3558 private AnnotationData createAnnotationData(int classRedefinedCount) { 3559 Map<Class<? extends Annotation>, Annotation> declaredAnnotations = 3560 AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this); 3561 Class<?> superClass = getSuperclass(); 3562 Map<Class<? extends Annotation>, Annotation> annotations = null; 3563 if (superClass != null) { 3564 Map<Class<? extends Annotation>, Annotation> superAnnotations = 3565 superClass.annotationData().annotations; 3566 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) { 3567 Class<? extends Annotation> annotationClass = e.getKey(); 3568 if (AnnotationType.getInstance(annotationClass).isInherited()) { 3569 if (annotations == null) { // lazy construction 3570 annotations = new LinkedHashMap<>((Math.max( 3571 declaredAnnotations.size(), 3572 Math.min(12, declaredAnnotations.size() + superAnnotations.size()) 3573 ) * 4 + 2) / 3 3574 ); 3575 } 3576 annotations.put(annotationClass, e.getValue()); 3577 } 3578 } 3579 } 3580 if (annotations == null) { 3581 // no inherited annotations -> share the Map with declaredAnnotations 3582 annotations = declaredAnnotations; 3583 } else { 3584 // at least one inherited annotation -> declared may override inherited 3585 annotations.putAll(declaredAnnotations); 3586 } 3587 return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount); 3588 } 3589 3590 // Annotation types cache their internal (AnnotationType) form 3591 3592 @SuppressWarnings("UnusedDeclaration") 3593 private volatile transient AnnotationType annotationType; 3594 3595 boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) { 3596 return Atomic.casAnnotationType(this, oldType, newType); 3597 } 3598 3599 AnnotationType getAnnotationType() { 3600 return annotationType; 3601 } 3602 3603 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() { 3604 return annotationData().declaredAnnotations; 3605 } 3606 3607 /* Backing store of user-defined values pertaining to this class. 3608 * Maintained by the ClassValue class. 3609 */ 3610 transient ClassValue.ClassValueMap classValueMap; 3611 3612 /** 3613 * Returns an {@code AnnotatedType} object that represents the use of a 3614 * type to specify the superclass of the entity represented by this {@code 3615 * Class} object. (The <em>use</em> of type Foo to specify the superclass 3616 * in '... extends Foo' is distinct from the <em>declaration</em> of type 3617 * Foo.) 3618 * 3619 * <p> If this {@code Class} object represents a type whose declaration 3620 * does not explicitly indicate an annotated superclass, then the return 3621 * value is an {@code AnnotatedType} object representing an element with no 3622 * annotations. 3623 * 3624 * <p> If this {@code Class} represents either the {@code Object} class, an 3625 * interface type, an array type, a primitive type, or void, the return 3626 * value is {@code null}. 3627 * 3628 * @return an object representing the superclass 3629 * @since 1.8 3630 */ 3631 public AnnotatedType getAnnotatedSuperclass() { 3632 if (this == Object.class || 3633 isInterface() || 3634 isArray() || 3635 isPrimitive() || 3636 this == Void.TYPE) { 3637 return null; 3638 } 3639 3640 return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this); 3641 } 3642 3643 /** 3644 * Returns an array of {@code AnnotatedType} objects that represent the use 3645 * of types to specify superinterfaces of the entity represented by this 3646 * {@code Class} object. (The <em>use</em> of type Foo to specify a 3647 * superinterface in '... implements Foo' is distinct from the 3648 * <em>declaration</em> of type Foo.) 3649 * 3650 * <p> If this {@code Class} object represents a class, the return value is 3651 * an array containing objects representing the uses of interface types to 3652 * specify interfaces implemented by the class. The order of the objects in 3653 * the array corresponds to the order of the interface types used in the 3654 * 'implements' clause of the declaration of this {@code Class} object. 3655 * 3656 * <p> If this {@code Class} object represents an interface, the return 3657 * value is an array containing objects representing the uses of interface 3658 * types to specify interfaces directly extended by the interface. The 3659 * order of the objects in the array corresponds to the order of the 3660 * interface types used in the 'extends' clause of the declaration of this 3661 * {@code Class} object. 3662 * 3663 * <p> If this {@code Class} object represents a class or interface whose 3664 * declaration does not explicitly indicate any annotated superinterfaces, 3665 * the return value is an array of length 0. 3666 * 3667 * <p> If this {@code Class} object represents either the {@code Object} 3668 * class, an array type, a primitive type, or void, the return value is an 3669 * array of length 0. 3670 * 3671 * @return an array representing the superinterfaces 3672 * @since 1.8 3673 */ 3674 public AnnotatedType[] getAnnotatedInterfaces() { 3675 return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this); 3676 } 3677 }