1 /* 2 * Copyright (c) 1994, 2010, 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.Array; 29 import java.lang.reflect.GenericArrayType; 30 import java.lang.reflect.Member; 31 import java.lang.reflect.Field; 32 import java.lang.reflect.Method; 33 import java.lang.reflect.Constructor; 34 import java.lang.reflect.Modifier; 35 import java.lang.reflect.Type; 36 import java.lang.reflect.TypeVariable; 37 import java.lang.reflect.InvocationTargetException; 38 import java.lang.ref.SoftReference; 39 import java.io.InputStream; 40 import java.io.ObjectStreamField; 41 import java.security.AccessController; 42 import java.security.PrivilegedAction; 43 import java.util.ArrayList; 44 import java.util.Arrays; 45 import java.util.Collection; 46 import java.util.HashSet; 47 import java.util.List; 48 import java.util.Set; 49 import java.util.Map; 50 import java.util.HashMap; 51 import sun.misc.Unsafe; 52 import sun.reflect.ConstantPool; 53 import sun.reflect.Reflection; 54 import sun.reflect.ReflectionFactory; 55 import sun.reflect.generics.factory.CoreReflectionFactory; 56 import sun.reflect.generics.factory.GenericsFactory; 57 import sun.reflect.generics.repository.ClassRepository; 58 import sun.reflect.generics.repository.MethodRepository; 59 import sun.reflect.generics.repository.ConstructorRepository; 60 import sun.reflect.generics.scope.ClassScope; 61 import sun.security.util.SecurityConstants; 62 import java.lang.annotation.Annotation; 63 import sun.reflect.annotation.*; 64 65 /** 66 * Instances of the class {@code Class} represent classes and 67 * interfaces in a running Java application. An enum is a kind of 68 * class and an annotation is a kind of interface. Every array also 69 * belongs to a class that is reflected as a {@code Class} object 70 * that is shared by all arrays with the same element type and number 71 * of dimensions. The primitive Java types ({@code boolean}, 72 * {@code byte}, {@code char}, {@code short}, 73 * {@code int}, {@code long}, {@code float}, and 74 * {@code double}), and the keyword {@code void} are also 75 * represented as {@code Class} objects. 76 * 77 * <p> {@code Class} has no public constructor. Instead {@code Class} 78 * objects are constructed automatically by the Java Virtual Machine as classes 79 * are loaded and by calls to the {@code defineClass} method in the class 80 * loader. 81 * 82 * <p> The following example uses a {@code Class} object to print the 83 * class name of an object: 84 * 85 * <p> <blockquote><pre> 86 * void printClassName(Object obj) { 87 * System.out.println("The class of " + obj + 88 * " is " + obj.getClass().getName()); 89 * } 90 * </pre></blockquote> 91 * 92 * <p> It is also possible to get the {@code Class} object for a named 93 * type (or for void) using a class literal. See Section 15.8.2 of 94 * <cite>The Java™ Language Specification</cite>. 95 * For example: 96 * 97 * <p> <blockquote> 98 * {@code System.out.println("The name of class Foo is: "+Foo.class.getName());} 99 * </blockquote> 100 * 101 * @param <T> the type of the class modeled by this {@code Class} 102 * object. For example, the type of {@code String.class} is {@code 103 * Class<String>}. Use {@code Class<?>} if the class being modeled is 104 * unknown. 105 * 106 * @author unascribed 107 * @see java.lang.ClassLoader#defineClass(byte[], int, int) 108 * @since JDK1.0 109 */ 110 public final 111 class Class<T> implements java.io.Serializable, 112 java.lang.reflect.GenericDeclaration, 113 java.lang.reflect.Type, 114 java.lang.reflect.AnnotatedElement { 115 private static final int ANNOTATION= 0x00002000; 116 private static final int ENUM = 0x00004000; 117 private static final int SYNTHETIC = 0x00001000; 118 119 private static native void registerNatives(); 120 static { 121 registerNatives(); 122 } 123 124 /* 125 * Constructor. Only the Java Virtual Machine creates Class 126 * objects. 127 */ 128 private Class() {} 129 130 131 /** 132 * Converts the object to a string. The string representation is the 133 * string "class" or "interface", followed by a space, and then by the 134 * fully qualified name of the class in the format returned by 135 * {@code getName}. If this {@code Class} object represents a 136 * primitive type, this method returns the name of the primitive type. If 137 * this {@code Class} object represents void this method returns 138 * "void". 139 * 140 * @return a string representation of this class object. 141 */ 142 public String toString() { 143 return (isInterface() ? "interface " : (isPrimitive() ? "" : "class ")) 144 + getName(); 145 } 146 147 148 /** 149 * Returns the {@code Class} object associated with the class or 150 * interface with the given string name. Invoking this method is 151 * equivalent to: 152 * 153 * <blockquote> 154 * {@code Class.forName(className, true, currentLoader)} 155 * </blockquote> 156 * 157 * where {@code currentLoader} denotes the defining class loader of 158 * the current class. 159 * 160 * <p> For example, the following code fragment returns the 161 * runtime {@code Class} descriptor for the class named 162 * {@code java.lang.Thread}: 163 * 164 * <blockquote> 165 * {@code Class t = Class.forName("java.lang.Thread")} 166 * </blockquote> 167 * <p> 168 * A call to {@code forName("X")} causes the class named 169 * {@code X} to be initialized. 170 * 171 * @param className the fully qualified name of the desired class. 172 * @return the {@code Class} object for the class with the 173 * specified name. 174 * @exception LinkageError if the linkage fails 175 * @exception ExceptionInInitializerError if the initialization provoked 176 * by this method fails 177 * @exception ClassNotFoundException if the class cannot be located 178 */ 179 public static Class<?> forName(String className) 180 throws ClassNotFoundException { 181 return forName0(className, true, ClassLoader.getCallerClassLoader()); 182 } 183 184 185 /** 186 * Returns the {@code Class} object associated with the class or 187 * interface with the given string name, using the given class loader. 188 * Given the fully qualified name for a class or interface (in the same 189 * format returned by {@code getName}) this method attempts to 190 * locate, load, and link the class or interface. The specified class 191 * loader is used to load the class or interface. If the parameter 192 * {@code loader} is null, the class is loaded through the bootstrap 193 * class loader. The class is initialized only if the 194 * {@code initialize} parameter is {@code true} and if it has 195 * not been initialized earlier. 196 * 197 * <p> If {@code name} denotes a primitive type or void, an attempt 198 * will be made to locate a user-defined class in the unnamed package whose 199 * name is {@code name}. Therefore, this method cannot be used to 200 * obtain any of the {@code Class} objects representing primitive 201 * types or void. 202 * 203 * <p> If {@code name} denotes an array class, the component type of 204 * the array class is loaded but not initialized. 205 * 206 * <p> For example, in an instance method the expression: 207 * 208 * <blockquote> 209 * {@code Class.forName("Foo")} 210 * </blockquote> 211 * 212 * is equivalent to: 213 * 214 * <blockquote> 215 * {@code Class.forName("Foo", true, this.getClass().getClassLoader())} 216 * </blockquote> 217 * 218 * Note that this method throws errors related to loading, linking or 219 * initializing as specified in Sections 12.2, 12.3 and 12.4 of <em>The 220 * Java Language Specification</em>. 221 * Note that this method does not check whether the requested class 222 * is accessible to its caller. 223 * 224 * <p> If the {@code loader} is {@code null}, and a security 225 * manager is present, and the caller's class loader is not null, then this 226 * method calls the security manager's {@code checkPermission} method 227 * with a {@code RuntimePermission("getClassLoader")} permission to 228 * ensure it's ok to access the bootstrap class loader. 229 * 230 * @param name fully qualified name of the desired class 231 * @param initialize whether the class must be initialized 232 * @param loader class loader from which the class must be loaded 233 * @return class object representing the desired class 234 * 235 * @exception LinkageError if the linkage fails 236 * @exception ExceptionInInitializerError if the initialization provoked 237 * by this method fails 238 * @exception ClassNotFoundException if the class cannot be located by 239 * the specified class loader 240 * 241 * @see java.lang.Class#forName(String) 242 * @see java.lang.ClassLoader 243 * @since 1.2 244 */ 245 public static Class<?> forName(String name, boolean initialize, 246 ClassLoader loader) 247 throws ClassNotFoundException 248 { 249 if (loader == null) { 250 SecurityManager sm = System.getSecurityManager(); 251 if (sm != null) { 252 ClassLoader ccl = ClassLoader.getCallerClassLoader(); 253 if (ccl != null) { 254 sm.checkPermission( 255 SecurityConstants.GET_CLASSLOADER_PERMISSION); 256 } 257 } 258 } 259 return forName0(name, initialize, loader); 260 } 261 262 /** Called after security checks have been made. */ 263 private static native Class<?> forName0(String name, boolean initialize, 264 ClassLoader loader) 265 throws ClassNotFoundException; 266 267 /** 268 * Creates a new instance of the class represented by this {@code Class} 269 * object. The class is instantiated as if by a {@code new} 270 * expression with an empty argument list. The class is initialized if it 271 * has not already been initialized. 272 * 273 * <p>Note that this method propagates any exception thrown by the 274 * nullary constructor, including a checked exception. Use of 275 * this method effectively bypasses the compile-time exception 276 * checking that would otherwise be performed by the compiler. 277 * The {@link 278 * java.lang.reflect.Constructor#newInstance(java.lang.Object...) 279 * Constructor.newInstance} method avoids this problem by wrapping 280 * any exception thrown by the constructor in a (checked) {@link 281 * java.lang.reflect.InvocationTargetException}. 282 * 283 * @return a newly allocated instance of the class represented by this 284 * object. 285 * @exception IllegalAccessException if the class or its nullary 286 * constructor is not accessible. 287 * @exception InstantiationException 288 * if this {@code Class} represents an abstract class, 289 * an interface, an array class, a primitive type, or void; 290 * or if the class has no nullary constructor; 291 * or if the instantiation fails for some other reason. 292 * @exception ExceptionInInitializerError if the initialization 293 * provoked by this method fails. 294 * @exception SecurityException 295 * If a security manager, <i>s</i>, is present and any of the 296 * following conditions is met: 297 * 298 * <ul> 299 * 300 * <li> invocation of 301 * {@link SecurityManager#checkMemberAccess 302 * s.checkMemberAccess(this, Member.PUBLIC)} denies 303 * creation of new instances of this class 304 * 305 * <li> the caller's class loader is not the same as or an 306 * ancestor of the class loader for the current class and 307 * invocation of {@link SecurityManager#checkPackageAccess 308 * s.checkPackageAccess()} denies access to the package 309 * of this class 310 * 311 * </ul> 312 * 313 */ 314 public T newInstance() 315 throws InstantiationException, IllegalAccessException 316 { 317 if (System.getSecurityManager() != null) { 318 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader()); 319 } 320 return newInstance0(); 321 } 322 323 private T newInstance0() 324 throws InstantiationException, IllegalAccessException 325 { 326 // NOTE: the following code may not be strictly correct under 327 // the current Java memory model. 328 329 // Constructor lookup 330 if (cachedConstructor == null) { 331 if (this == Class.class) { 332 throw new IllegalAccessException( 333 "Can not call newInstance() on the Class for java.lang.Class" 334 ); 335 } 336 try { 337 Class<?>[] empty = {}; 338 final Constructor<T> c = getConstructor0(empty, Member.DECLARED); 339 // Disable accessibility checks on the constructor 340 // since we have to do the security check here anyway 341 // (the stack depth is wrong for the Constructor's 342 // security check to work) 343 java.security.AccessController.doPrivileged( 344 new java.security.PrivilegedAction<Void>() { 345 public Void run() { 346 c.setAccessible(true); 347 return null; 348 } 349 }); 350 cachedConstructor = c; 351 } catch (NoSuchMethodException e) { 352 throw (InstantiationException) 353 new InstantiationException(getName()).initCause(e); 354 } 355 } 356 Constructor<T> tmpConstructor = cachedConstructor; 357 // Security check (same as in java.lang.reflect.Constructor) 358 int modifiers = tmpConstructor.getModifiers(); 359 if (!Reflection.quickCheckMemberAccess(this, modifiers)) { 360 Class<?> caller = Reflection.getCallerClass(3); 361 if (newInstanceCallerCache != caller) { 362 Reflection.ensureMemberAccess(caller, this, null, modifiers); 363 newInstanceCallerCache = caller; 364 } 365 } 366 // Run constructor 367 try { 368 return tmpConstructor.newInstance((Object[])null); 369 } catch (InvocationTargetException e) { 370 Unsafe.getUnsafe().throwException(e.getTargetException()); 371 // Not reached 372 return null; 373 } 374 } 375 private volatile transient Constructor<T> cachedConstructor; 376 private volatile transient Class<?> newInstanceCallerCache; 377 378 379 /** 380 * Determines if the specified {@code Object} is assignment-compatible 381 * with the object represented by this {@code Class}. This method is 382 * the dynamic equivalent of the Java language {@code instanceof} 383 * operator. The method returns {@code true} if the specified 384 * {@code Object} argument is non-null and can be cast to the 385 * reference type represented by this {@code Class} object without 386 * raising a {@code ClassCastException.} It returns {@code false} 387 * otherwise. 388 * 389 * <p> Specifically, if this {@code Class} object represents a 390 * declared class, this method returns {@code true} if the specified 391 * {@code Object} argument is an instance of the represented class (or 392 * of any of its subclasses); it returns {@code false} otherwise. If 393 * this {@code Class} object represents an array class, this method 394 * returns {@code true} if the specified {@code Object} argument 395 * can be converted to an object of the array class by an identity 396 * conversion or by a widening reference conversion; it returns 397 * {@code false} otherwise. If this {@code Class} object 398 * represents an interface, this method returns {@code true} if the 399 * class or any superclass of the specified {@code Object} argument 400 * implements this interface; it returns {@code false} otherwise. If 401 * this {@code Class} object represents a primitive type, this method 402 * returns {@code false}. 403 * 404 * @param obj the object to check 405 * @return true if {@code obj} is an instance of this class 406 * 407 * @since JDK1.1 408 */ 409 public native boolean isInstance(Object obj); 410 411 412 /** 413 * Determines if the class or interface represented by this 414 * {@code Class} object is either the same as, or is a superclass or 415 * superinterface of, the class or interface represented by the specified 416 * {@code Class} parameter. It returns {@code true} if so; 417 * otherwise it returns {@code false}. If this {@code Class} 418 * object represents a primitive type, this method returns 419 * {@code true} if the specified {@code Class} parameter is 420 * exactly this {@code Class} object; otherwise it returns 421 * {@code false}. 422 * 423 * <p> Specifically, this method tests whether the type represented by the 424 * specified {@code Class} parameter can be converted to the type 425 * represented by this {@code Class} object via an identity conversion 426 * or via a widening reference conversion. See <em>The Java Language 427 * Specification</em>, sections 5.1.1 and 5.1.4 , for details. 428 * 429 * @param cls the {@code Class} object to be checked 430 * @return the {@code boolean} value indicating whether objects of the 431 * type {@code cls} can be assigned to objects of this class 432 * @exception NullPointerException if the specified Class parameter is 433 * null. 434 * @since JDK1.1 435 */ 436 public native boolean isAssignableFrom(Class<?> cls); 437 438 439 /** 440 * Determines if the specified {@code Class} object represents an 441 * interface type. 442 * 443 * @return {@code true} if this object represents an interface; 444 * {@code false} otherwise. 445 */ 446 public native boolean isInterface(); 447 448 449 /** 450 * Determines if this {@code Class} object represents an array class. 451 * 452 * @return {@code true} if this object represents an array class; 453 * {@code false} otherwise. 454 * @since JDK1.1 455 */ 456 public native boolean isArray(); 457 458 459 /** 460 * Determines if the specified {@code Class} object represents a 461 * primitive type. 462 * 463 * <p> There are nine predefined {@code Class} objects to represent 464 * the eight primitive types and void. These are created by the Java 465 * Virtual Machine, and have the same names as the primitive types that 466 * they represent, namely {@code boolean}, {@code byte}, 467 * {@code char}, {@code short}, {@code int}, 468 * {@code long}, {@code float}, and {@code double}. 469 * 470 * <p> These objects may only be accessed via the following public static 471 * final variables, and are the only {@code Class} objects for which 472 * this method returns {@code true}. 473 * 474 * @return true if and only if this class represents a primitive type 475 * 476 * @see java.lang.Boolean#TYPE 477 * @see java.lang.Character#TYPE 478 * @see java.lang.Byte#TYPE 479 * @see java.lang.Short#TYPE 480 * @see java.lang.Integer#TYPE 481 * @see java.lang.Long#TYPE 482 * @see java.lang.Float#TYPE 483 * @see java.lang.Double#TYPE 484 * @see java.lang.Void#TYPE 485 * @since JDK1.1 486 */ 487 public native boolean isPrimitive(); 488 489 /** 490 * Returns true if this {@code Class} object represents an annotation 491 * type. Note that if this method returns true, {@link #isInterface()} 492 * would also return true, as all annotation types are also interfaces. 493 * 494 * @return {@code true} if this class object represents an annotation 495 * type; {@code false} otherwise 496 * @since 1.5 497 */ 498 public boolean isAnnotation() { 499 return (getModifiers() & ANNOTATION) != 0; 500 } 501 502 /** 503 * Returns {@code true} if this class is a synthetic class; 504 * returns {@code false} otherwise. 505 * @return {@code true} if and only if this class is a synthetic class as 506 * defined by the Java Language Specification. 507 * @since 1.5 508 */ 509 public boolean isSynthetic() { 510 return (getModifiers() & SYNTHETIC) != 0; 511 } 512 513 /** 514 * Returns the name of the entity (class, interface, array class, 515 * primitive type, or void) represented by this {@code Class} object, 516 * as a {@code String}. 517 * 518 * <p> If this class object represents a reference type that is not an 519 * array type then the binary name of the class is returned, as specified 520 * by 521 * <cite>The Java™ Language Specification</cite>. 522 * 523 * <p> If this class object represents a primitive type or void, then the 524 * name returned is a {@code String} equal to the Java language 525 * keyword corresponding to the primitive type or void. 526 * 527 * <p> If this class object represents a class of arrays, then the internal 528 * form of the name consists of the name of the element type preceded by 529 * one or more '{@code [}' characters representing the depth of the array 530 * nesting. The encoding of element type names is as follows: 531 * 532 * <blockquote><table summary="Element types and encodings"> 533 * <tr><th> Element Type <th> <th> Encoding 534 * <tr><td> boolean <td> <td align=center> Z 535 * <tr><td> byte <td> <td align=center> B 536 * <tr><td> char <td> <td align=center> C 537 * <tr><td> class or interface 538 * <td> <td align=center> L<i>classname</i>; 539 * <tr><td> double <td> <td align=center> D 540 * <tr><td> float <td> <td align=center> F 541 * <tr><td> int <td> <td align=center> I 542 * <tr><td> long <td> <td align=center> J 543 * <tr><td> short <td> <td align=center> S 544 * </table></blockquote> 545 * 546 * <p> The class or interface name <i>classname</i> is the binary name of 547 * the class specified above. 548 * 549 * <p> Examples: 550 * <blockquote><pre> 551 * String.class.getName() 552 * returns "java.lang.String" 553 * byte.class.getName() 554 * returns "byte" 555 * (new Object[3]).getClass().getName() 556 * returns "[Ljava.lang.Object;" 557 * (new int[3][4][5][6][7][8][9]).getClass().getName() 558 * returns "[[[[[[[I" 559 * </pre></blockquote> 560 * 561 * @return the name of the class or interface 562 * represented by this object. 563 */ 564 public String getName() { 565 String name = this.name; 566 if (name == null) 567 this.name = name = getName0(); 568 return name; 569 } 570 571 // cache the name to reduce the number of calls into the VM 572 private transient String name; 573 private native String getName0(); 574 575 /** 576 * Returns the class loader for the class. Some implementations may use 577 * null to represent the bootstrap class loader. This method will return 578 * null in such implementations if this class was loaded by the bootstrap 579 * class loader. 580 * 581 * <p> If a security manager is present, and the caller's class loader is 582 * not null and the caller's class loader is not the same as or an ancestor of 583 * the class loader for the class whose class loader is requested, then 584 * this method calls the security manager's {@code checkPermission} 585 * method with a {@code RuntimePermission("getClassLoader")} 586 * permission to ensure it's ok to access the class loader for the class. 587 * 588 * <p>If this object 589 * represents a primitive type or void, null is returned. 590 * 591 * @return the class loader that loaded the class or interface 592 * represented by this object. 593 * @throws SecurityException 594 * if a security manager exists and its 595 * {@code checkPermission} method denies 596 * access to the class loader for the class. 597 * @see java.lang.ClassLoader 598 * @see SecurityManager#checkPermission 599 * @see java.lang.RuntimePermission 600 */ 601 public ClassLoader getClassLoader() { 602 ClassLoader cl = getClassLoader0(); 603 if (cl == null) 604 return null; 605 SecurityManager sm = System.getSecurityManager(); 606 if (sm != null) { 607 ClassLoader ccl = ClassLoader.getCallerClassLoader(); 608 if (ccl != null && ccl != cl && !cl.isAncestor(ccl)) { 609 sm.checkPermission(SecurityConstants.GET_CLASSLOADER_PERMISSION); 610 } 611 } 612 return cl; 613 } 614 615 // Package-private to allow ClassLoader access 616 native ClassLoader getClassLoader0(); 617 618 619 /** 620 * Returns an array of {@code TypeVariable} objects that represent the 621 * type variables declared by the generic declaration represented by this 622 * {@code GenericDeclaration} object, in declaration order. Returns an 623 * array of length 0 if the underlying generic declaration declares no type 624 * variables. 625 * 626 * @return an array of {@code TypeVariable} objects that represent 627 * the type variables declared by this generic declaration 628 * @throws java.lang.reflect.GenericSignatureFormatError if the generic 629 * signature of this generic declaration does not conform to 630 * the format specified in 631 * <cite>The Java™ Virtual Machine Specification</cite> 632 * @since 1.5 633 */ 634 @SuppressWarnings("unchecked") 635 public TypeVariable<Class<T>>[] getTypeParameters() { 636 if (getGenericSignature() != null) 637 return (TypeVariable<Class<T>>[])getGenericInfo().getTypeParameters(); 638 else 639 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0]; 640 } 641 642 643 /** 644 * Returns the {@code Class} representing the superclass of the entity 645 * (class, interface, primitive type or void) represented by this 646 * {@code Class}. If this {@code Class} represents either the 647 * {@code Object} class, an interface, a primitive type, or void, then 648 * null is returned. If this object represents an array class then the 649 * {@code Class} object representing the {@code Object} class is 650 * returned. 651 * 652 * @return the superclass of the class represented by this object. 653 */ 654 public native Class<? super T> getSuperclass(); 655 656 657 /** 658 * Returns the {@code Type} representing the direct superclass of 659 * the entity (class, interface, primitive type or void) represented by 660 * this {@code Class}. 661 * 662 * <p>If the superclass is a parameterized type, the {@code Type} 663 * object returned must accurately reflect the actual type 664 * parameters used in the source code. The parameterized type 665 * representing the superclass is created if it had not been 666 * created before. See the declaration of {@link 667 * java.lang.reflect.ParameterizedType ParameterizedType} for the 668 * semantics of the creation process for parameterized types. If 669 * this {@code Class} represents either the {@code Object} 670 * class, an interface, a primitive type, or void, then null is 671 * returned. If this object represents an array class then the 672 * {@code Class} object representing the {@code Object} class is 673 * returned. 674 * 675 * @throws java.lang.reflect.GenericSignatureFormatError if the generic 676 * class signature does not conform to the format specified in 677 * <cite>The Java™ Virtual Machine Specification</cite> 678 * @throws TypeNotPresentException if the generic superclass 679 * refers to a non-existent type declaration 680 * @throws java.lang.reflect.MalformedParameterizedTypeException if the 681 * generic superclass refers to a parameterized type that cannot be 682 * instantiated for any reason 683 * @return the superclass of the class represented by this object 684 * @since 1.5 685 */ 686 public Type getGenericSuperclass() { 687 if (getGenericSignature() != null) { 688 // Historical irregularity: 689 // Generic signature marks interfaces with superclass = Object 690 // but this API returns null for interfaces 691 if (isInterface()) 692 return null; 693 return getGenericInfo().getSuperclass(); 694 } else 695 return getSuperclass(); 696 } 697 698 /** 699 * Gets the package for this class. The class loader of this class is used 700 * to find the package. If the class was loaded by the bootstrap class 701 * loader the set of packages loaded from CLASSPATH is searched to find the 702 * package of the class. Null is returned if no package object was created 703 * by the class loader of this class. 704 * 705 * <p> Packages have attributes for versions and specifications only if the 706 * information was defined in the manifests that accompany the classes, and 707 * if the class loader created the package instance with the attributes 708 * from the manifest. 709 * 710 * @return the package of the class, or null if no package 711 * information is available from the archive or codebase. 712 */ 713 public Package getPackage() { 714 return Package.getPackage(this); 715 } 716 717 718 /** 719 * Determines the interfaces implemented by the class or interface 720 * represented by this object. 721 * 722 * <p> If this object represents a class, the return value is an array 723 * containing objects representing all interfaces implemented by the 724 * class. The order of the interface objects in the array corresponds to 725 * the order of the interface names in the {@code implements} clause 726 * of the declaration of the class represented by this object. For 727 * example, given the declaration: 728 * <blockquote> 729 * {@code class Shimmer implements FloorWax, DessertTopping { ... }} 730 * </blockquote> 731 * suppose the value of {@code s} is an instance of 732 * {@code Shimmer}; the value of the expression: 733 * <blockquote> 734 * {@code s.getClass().getInterfaces()[0]} 735 * </blockquote> 736 * is the {@code Class} object that represents interface 737 * {@code FloorWax}; and the value of: 738 * <blockquote> 739 * {@code s.getClass().getInterfaces()[1]} 740 * </blockquote> 741 * is the {@code Class} object that represents interface 742 * {@code DessertTopping}. 743 * 744 * <p> If this object represents an interface, the array contains objects 745 * representing all interfaces extended by the interface. The order of the 746 * interface objects in the array corresponds to the order of the interface 747 * names in the {@code extends} clause of the declaration of the 748 * interface represented by this object. 749 * 750 * <p> If this object represents a class or interface that implements no 751 * interfaces, the method returns an array of length 0. 752 * 753 * <p> If this object represents a primitive type or void, the method 754 * returns an array of length 0. 755 * 756 * @return an array of interfaces implemented by this class. 757 */ 758 public native Class<?>[] getInterfaces(); 759 760 /** 761 * Returns the {@code Type}s representing the interfaces 762 * directly implemented by the class or interface represented by 763 * this object. 764 * 765 * <p>If a superinterface is a parameterized type, the 766 * {@code Type} object returned for it must accurately reflect 767 * the actual type parameters used in the source code. The 768 * parameterized type representing each superinterface is created 769 * if it had not been created before. See the declaration of 770 * {@link java.lang.reflect.ParameterizedType ParameterizedType} 771 * for the semantics of the creation process for parameterized 772 * types. 773 * 774 * <p> If this object represents a class, the return value is an 775 * array containing objects representing all interfaces 776 * implemented by the class. The order of the interface objects in 777 * the array corresponds to the order of the interface names in 778 * the {@code implements} clause of the declaration of the class 779 * represented by this object. In the case of an array class, the 780 * interfaces {@code Cloneable} and {@code Serializable} are 781 * returned in that order. 782 * 783 * <p>If this object represents an interface, the array contains 784 * objects representing all interfaces directly extended by the 785 * interface. The order of the interface objects in the array 786 * corresponds to the order of the interface names in the 787 * {@code extends} clause of the declaration of the interface 788 * represented by this object. 789 * 790 * <p>If this object represents a class or interface that 791 * implements no interfaces, the method returns an array of length 792 * 0. 793 * 794 * <p>If this object represents a primitive type or void, the 795 * method returns an array of length 0. 796 * 797 * @throws java.lang.reflect.GenericSignatureFormatError 798 * if the generic class signature does not conform to the format 799 * specified in 800 * <cite>The Java™ Virtual Machine Specification</cite> 801 * @throws TypeNotPresentException if any of the generic 802 * superinterfaces refers to a non-existent type declaration 803 * @throws java.lang.reflect.MalformedParameterizedTypeException 804 * if any of the generic superinterfaces refer to a parameterized 805 * type that cannot be instantiated for any reason 806 * @return an array of interfaces implemented by this class 807 * @since 1.5 808 */ 809 public Type[] getGenericInterfaces() { 810 if (getGenericSignature() != null) 811 return getGenericInfo().getSuperInterfaces(); 812 else 813 return getInterfaces(); 814 } 815 816 817 /** 818 * Returns the {@code Class} representing the component type of an 819 * array. If this class does not represent an array class this method 820 * returns null. 821 * 822 * @return the {@code Class} representing the component type of this 823 * class if this class is an array 824 * @see java.lang.reflect.Array 825 * @since JDK1.1 826 */ 827 public native Class<?> getComponentType(); 828 829 830 /** 831 * Returns the Java language modifiers for this class or interface, encoded 832 * in an integer. The modifiers consist of the Java Virtual Machine's 833 * constants for {@code public}, {@code protected}, 834 * {@code private}, {@code final}, {@code static}, 835 * {@code abstract} and {@code interface}; they should be decoded 836 * using the methods of class {@code Modifier}. 837 * 838 * <p> If the underlying class is an array class, then its 839 * {@code public}, {@code private} and {@code protected} 840 * modifiers are the same as those of its component type. If this 841 * {@code Class} represents a primitive type or void, its 842 * {@code public} modifier is always {@code true}, and its 843 * {@code protected} and {@code private} modifiers are always 844 * {@code false}. If this object represents an array class, a 845 * primitive type or void, then its {@code final} modifier is always 846 * {@code true} and its interface modifier is always 847 * {@code false}. The values of its other modifiers are not determined 848 * by this specification. 849 * 850 * <p> The modifier encodings are defined in <em>The Java Virtual Machine 851 * Specification</em>, table 4.1. 852 * 853 * @return the {@code int} representing the modifiers for this class 854 * @see java.lang.reflect.Modifier 855 * @since JDK1.1 856 */ 857 public native int getModifiers(); 858 859 860 /** 861 * Gets the signers of this class. 862 * 863 * @return the signers of this class, or null if there are no signers. In 864 * particular, this method returns null if this object represents 865 * a primitive type or void. 866 * @since JDK1.1 867 */ 868 public native Object[] getSigners(); 869 870 871 /** 872 * Set the signers of this class. 873 */ 874 native void setSigners(Object[] signers); 875 876 877 /** 878 * If this {@code Class} object represents a local or anonymous 879 * class within a method, returns a {@link 880 * java.lang.reflect.Method Method} object representing the 881 * immediately enclosing method of the underlying class. Returns 882 * {@code null} otherwise. 883 * 884 * In particular, this method returns {@code null} if the underlying 885 * class is a local or anonymous class immediately enclosed by a type 886 * declaration, instance initializer or static initializer. 887 * 888 * @return the immediately enclosing method of the underlying class, if 889 * that class is a local or anonymous class; otherwise {@code null}. 890 * @since 1.5 891 */ 892 public Method getEnclosingMethod() { 893 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo(); 894 895 if (enclosingInfo == null) 896 return null; 897 else { 898 if (!enclosingInfo.isMethod()) 899 return null; 900 901 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(), 902 getFactory()); 903 Class<?> returnType = toClass(typeInfo.getReturnType()); 904 Type [] parameterTypes = typeInfo.getParameterTypes(); 905 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length]; 906 907 // Convert Types to Classes; returned types *should* 908 // be class objects since the methodDescriptor's used 909 // don't have generics information 910 for(int i = 0; i < parameterClasses.length; i++) 911 parameterClasses[i] = toClass(parameterTypes[i]); 912 913 /* 914 * Loop over all declared methods; match method name, 915 * number of and type of parameters, *and* return 916 * type. Matching return type is also necessary 917 * because of covariant returns, etc. 918 */ 919 for(Method m: enclosingInfo.getEnclosingClass().getDeclaredMethods()) { 920 if (m.getName().equals(enclosingInfo.getName()) ) { 921 Class<?>[] candidateParamClasses = m.getParameterTypes(); 922 if (candidateParamClasses.length == parameterClasses.length) { 923 boolean matches = true; 924 for(int i = 0; i < candidateParamClasses.length; i++) { 925 if (!candidateParamClasses[i].equals(parameterClasses[i])) { 926 matches = false; 927 break; 928 } 929 } 930 931 if (matches) { // finally, check return type 932 if (m.getReturnType().equals(returnType) ) 933 return m; 934 } 935 } 936 } 937 } 938 939 throw new InternalError("Enclosing method not found"); 940 } 941 } 942 943 private native Object[] getEnclosingMethod0(); 944 945 private EnclosingMethodInfo getEnclosingMethodInfo() { 946 Object[] enclosingInfo = getEnclosingMethod0(); 947 if (enclosingInfo == null) 948 return null; 949 else { 950 return new EnclosingMethodInfo(enclosingInfo); 951 } 952 } 953 954 private final static class EnclosingMethodInfo { 955 private Class<?> enclosingClass; 956 private String name; 957 private String descriptor; 958 959 private EnclosingMethodInfo(Object[] enclosingInfo) { 960 if (enclosingInfo.length != 3) 961 throw new InternalError("Malformed enclosing method information"); 962 try { 963 // The array is expected to have three elements: 964 965 // the immediately enclosing class 966 enclosingClass = (Class<?>) enclosingInfo[0]; 967 assert(enclosingClass != null); 968 969 // the immediately enclosing method or constructor's 970 // name (can be null). 971 name = (String) enclosingInfo[1]; 972 973 // the immediately enclosing method or constructor's 974 // descriptor (null iff name is). 975 descriptor = (String) enclosingInfo[2]; 976 assert((name != null && descriptor != null) || name == descriptor); 977 } catch (ClassCastException cce) { 978 throw new InternalError("Invalid type in enclosing method information", cce); 979 } 980 } 981 982 boolean isPartial() { 983 return enclosingClass == null || name == null || descriptor == null; 984 } 985 986 boolean isConstructor() { return !isPartial() && "<init>".equals(name); } 987 988 boolean isMethod() { return !isPartial() && !isConstructor() && !"<clinit>".equals(name); } 989 990 Class<?> getEnclosingClass() { return enclosingClass; } 991 992 String getName() { return name; } 993 994 String getDescriptor() { return descriptor; } 995 996 } 997 998 private static Class<?> toClass(Type o) { 999 if (o instanceof GenericArrayType) 1000 return Array.newInstance(toClass(((GenericArrayType)o).getGenericComponentType()), 1001 0) 1002 .getClass(); 1003 return (Class<?>)o; 1004 } 1005 1006 /** 1007 * If this {@code Class} object represents a local or anonymous 1008 * class within a constructor, returns a {@link 1009 * java.lang.reflect.Constructor Constructor} object representing 1010 * the immediately enclosing constructor of the underlying 1011 * class. Returns {@code null} otherwise. In particular, this 1012 * method returns {@code null} if the underlying class is a local 1013 * or anonymous class immediately enclosed by a type declaration, 1014 * instance initializer or static initializer. 1015 * 1016 * @return the immediately enclosing constructor of the underlying class, if 1017 * that class is a local or anonymous class; otherwise {@code null}. 1018 * @since 1.5 1019 */ 1020 public Constructor<?> getEnclosingConstructor() { 1021 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo(); 1022 1023 if (enclosingInfo == null) 1024 return null; 1025 else { 1026 if (!enclosingInfo.isConstructor()) 1027 return null; 1028 1029 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(), 1030 getFactory()); 1031 Type [] parameterTypes = typeInfo.getParameterTypes(); 1032 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length]; 1033 1034 // Convert Types to Classes; returned types *should* 1035 // be class objects since the methodDescriptor's used 1036 // don't have generics information 1037 for(int i = 0; i < parameterClasses.length; i++) 1038 parameterClasses[i] = toClass(parameterTypes[i]); 1039 1040 /* 1041 * Loop over all declared constructors; match number 1042 * of and type of parameters. 1043 */ 1044 for(Constructor<?> c: enclosingInfo.getEnclosingClass().getDeclaredConstructors()) { 1045 Class<?>[] candidateParamClasses = c.getParameterTypes(); 1046 if (candidateParamClasses.length == parameterClasses.length) { 1047 boolean matches = true; 1048 for(int i = 0; i < candidateParamClasses.length; i++) { 1049 if (!candidateParamClasses[i].equals(parameterClasses[i])) { 1050 matches = false; 1051 break; 1052 } 1053 } 1054 1055 if (matches) 1056 return c; 1057 } 1058 } 1059 1060 throw new InternalError("Enclosing constructor not found"); 1061 } 1062 } 1063 1064 1065 /** 1066 * If the class or interface represented by this {@code Class} object 1067 * is a member of another class, returns the {@code Class} object 1068 * representing the class in which it was declared. This method returns 1069 * null if this class or interface is not a member of any other class. If 1070 * this {@code Class} object represents an array class, a primitive 1071 * type, or void,then this method returns null. 1072 * 1073 * @return the declaring class for this class 1074 * @since JDK1.1 1075 */ 1076 public native Class<?> getDeclaringClass(); 1077 1078 1079 /** 1080 * Returns the immediately enclosing class of the underlying 1081 * class. If the underlying class is a top level class this 1082 * method returns {@code null}. 1083 * @return the immediately enclosing class of the underlying class 1084 * @since 1.5 1085 */ 1086 public Class<?> getEnclosingClass() { 1087 // There are five kinds of classes (or interfaces): 1088 // a) Top level classes 1089 // b) Nested classes (static member classes) 1090 // c) Inner classes (non-static member classes) 1091 // d) Local classes (named classes declared within a method) 1092 // e) Anonymous classes 1093 1094 1095 // JVM Spec 4.8.6: A class must have an EnclosingMethod 1096 // attribute if and only if it is a local class or an 1097 // anonymous class. 1098 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo(); 1099 1100 if (enclosingInfo == null) { 1101 // This is a top level or a nested class or an inner class (a, b, or c) 1102 return getDeclaringClass(); 1103 } else { 1104 Class<?> enclosingClass = enclosingInfo.getEnclosingClass(); 1105 // This is a local class or an anonymous class (d or e) 1106 if (enclosingClass == this || enclosingClass == null) 1107 throw new InternalError("Malformed enclosing method information"); 1108 else 1109 return enclosingClass; 1110 } 1111 } 1112 1113 /** 1114 * Returns the simple name of the underlying class as given in the 1115 * source code. Returns an empty string if the underlying class is 1116 * anonymous. 1117 * 1118 * <p>The simple name of an array is the simple name of the 1119 * component type with "[]" appended. In particular the simple 1120 * name of an array whose component type is anonymous is "[]". 1121 * 1122 * @return the simple name of the underlying class 1123 * @since 1.5 1124 */ 1125 public String getSimpleName() { 1126 if (isArray()) 1127 return getComponentType().getSimpleName()+"[]"; 1128 1129 String simpleName = getSimpleBinaryName(); 1130 if (simpleName == null) { // top level class 1131 simpleName = getName(); 1132 return simpleName.substring(simpleName.lastIndexOf(".")+1); // strip the package name 1133 } 1134 // According to JLS3 "Binary Compatibility" (13.1) the binary 1135 // name of non-package classes (not top level) is the binary 1136 // name of the immediately enclosing class followed by a '$' followed by: 1137 // (for nested and inner classes): the simple name. 1138 // (for local classes): 1 or more digits followed by the simple name. 1139 // (for anonymous classes): 1 or more digits. 1140 1141 // Since getSimpleBinaryName() will strip the binary name of 1142 // the immediatly enclosing class, we are now looking at a 1143 // string that matches the regular expression "\$[0-9]*" 1144 // followed by a simple name (considering the simple of an 1145 // anonymous class to be the empty string). 1146 1147 // Remove leading "\$[0-9]*" from the name 1148 int length = simpleName.length(); 1149 if (length < 1 || simpleName.charAt(0) != '$') 1150 throw new InternalError("Malformed class name"); 1151 int index = 1; 1152 while (index < length && isAsciiDigit(simpleName.charAt(index))) 1153 index++; 1154 // Eventually, this is the empty string iff this is an anonymous class 1155 return simpleName.substring(index); 1156 } 1157 1158 /** 1159 * Character.isDigit answers {@code true} to some non-ascii 1160 * digits. This one does not. 1161 */ 1162 private static boolean isAsciiDigit(char c) { 1163 return '0' <= c && c <= '9'; 1164 } 1165 1166 /** 1167 * Returns the canonical name of the underlying class as 1168 * defined by the Java Language Specification. Returns null if 1169 * the underlying class does not have a canonical name (i.e., if 1170 * it is a local or anonymous class or an array whose component 1171 * type does not have a canonical name). 1172 * @return the canonical name of the underlying class if it exists, and 1173 * {@code null} otherwise. 1174 * @since 1.5 1175 */ 1176 public String getCanonicalName() { 1177 if (isArray()) { 1178 String canonicalName = getComponentType().getCanonicalName(); 1179 if (canonicalName != null) 1180 return canonicalName + "[]"; 1181 else 1182 return null; 1183 } 1184 if (isLocalOrAnonymousClass()) 1185 return null; 1186 Class<?> enclosingClass = getEnclosingClass(); 1187 if (enclosingClass == null) { // top level class 1188 return getName(); 1189 } else { 1190 String enclosingName = enclosingClass.getCanonicalName(); 1191 if (enclosingName == null) 1192 return null; 1193 return enclosingName + "." + getSimpleName(); 1194 } 1195 } 1196 1197 /** 1198 * Returns {@code true} if and only if the underlying class 1199 * is an anonymous class. 1200 * 1201 * @return {@code true} if and only if this class is an anonymous class. 1202 * @since 1.5 1203 */ 1204 public boolean isAnonymousClass() { 1205 return "".equals(getSimpleName()); 1206 } 1207 1208 /** 1209 * Returns {@code true} if and only if the underlying class 1210 * is a local class. 1211 * 1212 * @return {@code true} if and only if this class is a local class. 1213 * @since 1.5 1214 */ 1215 public boolean isLocalClass() { 1216 return isLocalOrAnonymousClass() && !isAnonymousClass(); 1217 } 1218 1219 /** 1220 * Returns {@code true} if and only if the underlying class 1221 * is a member class. 1222 * 1223 * @return {@code true} if and only if this class is a member class. 1224 * @since 1.5 1225 */ 1226 public boolean isMemberClass() { 1227 return getSimpleBinaryName() != null && !isLocalOrAnonymousClass(); 1228 } 1229 1230 /** 1231 * Returns the "simple binary name" of the underlying class, i.e., 1232 * the binary name without the leading enclosing class name. 1233 * Returns {@code null} if the underlying class is a top level 1234 * class. 1235 */ 1236 private String getSimpleBinaryName() { 1237 Class<?> enclosingClass = getEnclosingClass(); 1238 if (enclosingClass == null) // top level class 1239 return null; 1240 // Otherwise, strip the enclosing class' name 1241 try { 1242 return getName().substring(enclosingClass.getName().length()); 1243 } catch (IndexOutOfBoundsException ex) { 1244 throw new InternalError("Malformed class name", ex); 1245 } 1246 } 1247 1248 /** 1249 * Returns {@code true} if this is a local class or an anonymous 1250 * class. Returns {@code false} otherwise. 1251 */ 1252 private boolean isLocalOrAnonymousClass() { 1253 // JVM Spec 4.8.6: A class must have an EnclosingMethod 1254 // attribute if and only if it is a local class or an 1255 // anonymous class. 1256 return getEnclosingMethodInfo() != null; 1257 } 1258 1259 /** 1260 * Returns an array containing {@code Class} objects representing all 1261 * the public classes and interfaces that are members of the class 1262 * represented by this {@code Class} object. This includes public 1263 * class and interface members inherited from superclasses and public class 1264 * and interface members declared by the class. This method returns an 1265 * array of length 0 if this {@code Class} object has no public member 1266 * classes or interfaces. This method also returns an array of length 0 if 1267 * this {@code Class} object represents a primitive type, an array 1268 * class, or void. 1269 * 1270 * @return the array of {@code Class} objects representing the public 1271 * members of this class 1272 * @exception SecurityException 1273 * If a security manager, <i>s</i>, is present and any of the 1274 * following conditions is met: 1275 * 1276 * <ul> 1277 * 1278 * <li> invocation of 1279 * {@link SecurityManager#checkMemberAccess 1280 * s.checkMemberAccess(this, Member.PUBLIC)} method 1281 * denies access to the classes within this class 1282 * 1283 * <li> the caller's class loader is not the same as or an 1284 * ancestor of the class loader for the current class and 1285 * invocation of {@link SecurityManager#checkPackageAccess 1286 * s.checkPackageAccess()} denies access to the package 1287 * of this class 1288 * 1289 * </ul> 1290 * 1291 * @since JDK1.1 1292 */ 1293 public Class<?>[] getClasses() { 1294 // be very careful not to change the stack depth of this 1295 // checkMemberAccess call for security reasons 1296 // see java.lang.SecurityManager.checkMemberAccess 1297 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader()); 1298 1299 // Privileged so this implementation can look at DECLARED classes, 1300 // something the caller might not have privilege to do. The code here 1301 // is allowed to look at DECLARED classes because (1) it does not hand 1302 // out anything other than public members and (2) public member access 1303 // has already been ok'd by the SecurityManager. 1304 1305 return java.security.AccessController.doPrivileged( 1306 new java.security.PrivilegedAction<Class<?>[]>() { 1307 public Class<?>[] run() { 1308 List<Class<?>> list = new ArrayList<>(); 1309 Class<?> currentClass = Class.this; 1310 while (currentClass != null) { 1311 Class<?>[] members = currentClass.getDeclaredClasses(); 1312 for (int i = 0; i < members.length; i++) { 1313 if (Modifier.isPublic(members[i].getModifiers())) { 1314 list.add(members[i]); 1315 } 1316 } 1317 currentClass = currentClass.getSuperclass(); 1318 } 1319 return list.toArray(new Class<?>[0]); 1320 } 1321 }); 1322 } 1323 1324 1325 /** 1326 * Returns an array containing {@code Field} objects reflecting all 1327 * the accessible public fields of the class or interface represented by 1328 * this {@code Class} object. The elements in the array returned are 1329 * not sorted and are not in any particular order. This method returns an 1330 * array of length 0 if the class or interface has no accessible public 1331 * fields, or if it represents an array class, a primitive type, or void. 1332 * 1333 * <p> Specifically, if this {@code Class} object represents a class, 1334 * this method returns the public fields of this class and of all its 1335 * superclasses. If this {@code Class} object represents an 1336 * interface, this method returns the fields of this interface and of all 1337 * its superinterfaces. 1338 * 1339 * <p> The implicit length field for array class is not reflected by this 1340 * method. User code should use the methods of class {@code Array} to 1341 * manipulate arrays. 1342 * 1343 * <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.3. 1344 * 1345 * @return the array of {@code Field} objects representing the 1346 * public fields 1347 * @exception SecurityException 1348 * If a security manager, <i>s</i>, is present and any of the 1349 * following conditions is met: 1350 * 1351 * <ul> 1352 * 1353 * <li> invocation of 1354 * {@link SecurityManager#checkMemberAccess 1355 * s.checkMemberAccess(this, Member.PUBLIC)} denies 1356 * access to the fields within this class 1357 * 1358 * <li> the caller's class loader is not the same as or an 1359 * ancestor of the class loader for the current class and 1360 * invocation of {@link SecurityManager#checkPackageAccess 1361 * s.checkPackageAccess()} denies access to the package 1362 * of this class 1363 * 1364 * </ul> 1365 * 1366 * @since JDK1.1 1367 */ 1368 public Field[] getFields() throws SecurityException { 1369 // be very careful not to change the stack depth of this 1370 // checkMemberAccess call for security reasons 1371 // see java.lang.SecurityManager.checkMemberAccess 1372 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader()); 1373 return copyFields(privateGetPublicFields(null)); 1374 } 1375 1376 1377 /** 1378 * Returns an array containing {@code Method} objects reflecting all 1379 * the public <em>member</em> methods of the class or interface represented 1380 * by this {@code Class} object, including those declared by the class 1381 * or interface and those inherited from superclasses and 1382 * superinterfaces. Array classes return all the (public) member methods 1383 * inherited from the {@code Object} class. The elements in the array 1384 * returned are not sorted and are not in any particular order. This 1385 * method returns an array of length 0 if this {@code Class} object 1386 * represents a class or interface that has no public member methods, or if 1387 * this {@code Class} object represents a primitive type or void. 1388 * 1389 * <p> The class initialization method {@code <clinit>} is not 1390 * included in the returned array. If the class declares multiple public 1391 * member methods with the same parameter types, they are all included in 1392 * the returned array. 1393 * 1394 * <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.4. 1395 * 1396 * @return the array of {@code Method} objects representing the 1397 * public methods of this class 1398 * @exception SecurityException 1399 * If a security manager, <i>s</i>, is present and any of the 1400 * following conditions is met: 1401 * 1402 * <ul> 1403 * 1404 * <li> invocation of 1405 * {@link SecurityManager#checkMemberAccess 1406 * s.checkMemberAccess(this, Member.PUBLIC)} denies 1407 * access to the methods within this class 1408 * 1409 * <li> the caller's class loader is not the same as or an 1410 * ancestor of the class loader for the current class and 1411 * invocation of {@link SecurityManager#checkPackageAccess 1412 * s.checkPackageAccess()} denies access to the package 1413 * of this class 1414 * 1415 * </ul> 1416 * 1417 * @since JDK1.1 1418 */ 1419 public Method[] getMethods() throws SecurityException { 1420 // be very careful not to change the stack depth of this 1421 // checkMemberAccess call for security reasons 1422 // see java.lang.SecurityManager.checkMemberAccess 1423 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader()); 1424 return copyMethods(privateGetPublicMethods()); 1425 } 1426 1427 1428 /** 1429 * Returns an array containing {@code Constructor} objects reflecting 1430 * all the public constructors of the class represented by this 1431 * {@code Class} object. An array of length 0 is returned if the 1432 * class has no public constructors, or if the class is an array class, or 1433 * if the class reflects a primitive type or void. 1434 * 1435 * Note that while this method returns an array of {@code 1436 * Constructor<T>} objects (that is an array of constructors from 1437 * this class), the return type of this method is {@code 1438 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as 1439 * might be expected. This less informative return type is 1440 * necessary since after being returned from this method, the 1441 * array could be modified to hold {@code Constructor} objects for 1442 * different classes, which would violate the type guarantees of 1443 * {@code Constructor<T>[]}. 1444 * 1445 * @return the array of {@code Constructor} objects representing the 1446 * public constructors of this class 1447 * @exception SecurityException 1448 * If a security manager, <i>s</i>, is present and any of the 1449 * following conditions is met: 1450 * 1451 * <ul> 1452 * 1453 * <li> invocation of 1454 * {@link SecurityManager#checkMemberAccess 1455 * s.checkMemberAccess(this, Member.PUBLIC)} denies 1456 * access to the constructors within this class 1457 * 1458 * <li> the caller's class loader is not the same as or an 1459 * ancestor of the class loader for the current class and 1460 * invocation of {@link SecurityManager#checkPackageAccess 1461 * s.checkPackageAccess()} denies access to the package 1462 * of this class 1463 * 1464 * </ul> 1465 * 1466 * @since JDK1.1 1467 */ 1468 public Constructor<?>[] getConstructors() throws SecurityException { 1469 // be very careful not to change the stack depth of this 1470 // checkMemberAccess call for security reasons 1471 // see java.lang.SecurityManager.checkMemberAccess 1472 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader()); 1473 return copyConstructors(privateGetDeclaredConstructors(true)); 1474 } 1475 1476 1477 /** 1478 * Returns a {@code Field} object that reflects the specified public 1479 * member field of the class or interface represented by this 1480 * {@code Class} object. The {@code name} parameter is a 1481 * {@code String} specifying the simple name of the desired field. 1482 * 1483 * <p> The field to be reflected is determined by the algorithm that 1484 * follows. Let C be the class represented by this object: 1485 * <OL> 1486 * <LI> If C declares a public field with the name specified, that is the 1487 * field to be reflected.</LI> 1488 * <LI> If no field was found in step 1 above, this algorithm is applied 1489 * recursively to each direct superinterface of C. The direct 1490 * superinterfaces are searched in the order they were declared.</LI> 1491 * <LI> If no field was found in steps 1 and 2 above, and C has a 1492 * superclass S, then this algorithm is invoked recursively upon S. 1493 * If C has no superclass, then a {@code NoSuchFieldException} 1494 * is thrown.</LI> 1495 * </OL> 1496 * 1497 * <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.3. 1498 * 1499 * @param name the field name 1500 * @return the {@code Field} object of this class specified by 1501 * {@code name} 1502 * @exception NoSuchFieldException if a field with the specified name is 1503 * not found. 1504 * @exception NullPointerException if {@code name} is {@code null} 1505 * @exception SecurityException 1506 * If a security manager, <i>s</i>, is present and any of the 1507 * following conditions is met: 1508 * 1509 * <ul> 1510 * 1511 * <li> invocation of 1512 * {@link SecurityManager#checkMemberAccess 1513 * s.checkMemberAccess(this, Member.PUBLIC)} denies 1514 * access to the field 1515 * 1516 * <li> the caller's class loader is not the same as or an 1517 * ancestor of the class loader for the current class and 1518 * invocation of {@link SecurityManager#checkPackageAccess 1519 * s.checkPackageAccess()} denies access to the package 1520 * of this class 1521 * 1522 * </ul> 1523 * 1524 * @since JDK1.1 1525 */ 1526 public Field getField(String name) 1527 throws NoSuchFieldException, SecurityException { 1528 // be very careful not to change the stack depth of this 1529 // checkMemberAccess call for security reasons 1530 // see java.lang.SecurityManager.checkMemberAccess 1531 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader()); 1532 Field field = getField0(name); 1533 if (field == null) { 1534 throw new NoSuchFieldException(name); 1535 } 1536 return field; 1537 } 1538 1539 1540 /** 1541 * Returns a {@code Method} object that reflects the specified public 1542 * member method of the class or interface represented by this 1543 * {@code Class} object. The {@code name} parameter is a 1544 * {@code String} specifying the simple name of the desired method. The 1545 * {@code parameterTypes} parameter is an array of {@code Class} 1546 * objects that identify the method's formal parameter types, in declared 1547 * order. If {@code parameterTypes} is {@code null}, it is 1548 * treated as if it were an empty array. 1549 * 1550 * <p> If the {@code name} is "{@code <init>};"or "{@code <clinit>}" a 1551 * {@code NoSuchMethodException} is raised. Otherwise, the method to 1552 * be reflected is determined by the algorithm that follows. Let C be the 1553 * class represented by this object: 1554 * <OL> 1555 * <LI> C is searched for any <I>matching methods</I>. If no matching 1556 * method is found, the algorithm of step 1 is invoked recursively on 1557 * the superclass of C.</LI> 1558 * <LI> If no method was found in step 1 above, the superinterfaces of C 1559 * are searched for a matching method. If any such method is found, it 1560 * is reflected.</LI> 1561 * </OL> 1562 * 1563 * To find a matching method in a class C: If C declares exactly one 1564 * public method with the specified name and exactly the same formal 1565 * parameter types, that is the method reflected. If more than one such 1566 * method is found in C, and one of these methods has a return type that is 1567 * more specific than any of the others, that method is reflected; 1568 * otherwise one of the methods is chosen arbitrarily. 1569 * 1570 * <p>Note that there may be more than one matching method in a 1571 * class because while the Java language forbids a class to 1572 * declare multiple methods with the same signature but different 1573 * return types, the Java virtual machine does not. This 1574 * increased flexibility in the virtual machine can be used to 1575 * implement various language features. For example, covariant 1576 * returns can be implemented with {@linkplain 1577 * java.lang.reflect.Method#isBridge bridge methods}; the bridge 1578 * method and the method being overridden would have the same 1579 * signature but different return types. 1580 * 1581 * <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.4. 1582 * 1583 * @param name the name of the method 1584 * @param parameterTypes the list of parameters 1585 * @return the {@code Method} object that matches the specified 1586 * {@code name} and {@code parameterTypes} 1587 * @exception NoSuchMethodException if a matching method is not found 1588 * or if the name is "<init>"or "<clinit>". 1589 * @exception NullPointerException if {@code name} is {@code null} 1590 * @exception SecurityException 1591 * If a security manager, <i>s</i>, is present and any of the 1592 * following conditions is met: 1593 * 1594 * <ul> 1595 * 1596 * <li> invocation of 1597 * {@link SecurityManager#checkMemberAccess 1598 * s.checkMemberAccess(this, Member.PUBLIC)} denies 1599 * access to the method 1600 * 1601 * <li> the caller's class loader is not the same as or an 1602 * ancestor of the class loader for the current class and 1603 * invocation of {@link SecurityManager#checkPackageAccess 1604 * s.checkPackageAccess()} denies access to the package 1605 * of this class 1606 * 1607 * </ul> 1608 * 1609 * @since JDK1.1 1610 */ 1611 public Method getMethod(String name, Class<?>... parameterTypes) 1612 throws NoSuchMethodException, SecurityException { 1613 // be very careful not to change the stack depth of this 1614 // checkMemberAccess call for security reasons 1615 // see java.lang.SecurityManager.checkMemberAccess 1616 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader()); 1617 Method method = getMethod0(name, parameterTypes); 1618 if (method == null) { 1619 throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes)); 1620 } 1621 return method; 1622 } 1623 1624 1625 /** 1626 * Returns a {@code Constructor} object that reflects the specified 1627 * public constructor of the class represented by this {@code Class} 1628 * object. The {@code parameterTypes} parameter is an array of 1629 * {@code Class} objects that identify the constructor's formal 1630 * parameter types, in declared order. 1631 * 1632 * If this {@code Class} object represents an inner class 1633 * declared in a non-static context, the formal parameter types 1634 * include the explicit enclosing instance as the first parameter. 1635 * 1636 * <p> The constructor to reflect is the public constructor of the class 1637 * represented by this {@code Class} object whose formal parameter 1638 * types match those specified by {@code parameterTypes}. 1639 * 1640 * @param parameterTypes the parameter array 1641 * @return the {@code Constructor} object of the public constructor that 1642 * matches the specified {@code parameterTypes} 1643 * @exception NoSuchMethodException if a matching method is not found. 1644 * @exception SecurityException 1645 * If a security manager, <i>s</i>, is present and any of the 1646 * following conditions is met: 1647 * 1648 * <ul> 1649 * 1650 * <li> invocation of 1651 * {@link SecurityManager#checkMemberAccess 1652 * s.checkMemberAccess(this, Member.PUBLIC)} denies 1653 * access to the constructor 1654 * 1655 * <li> the caller's class loader is not the same as or an 1656 * ancestor of the class loader for the current class and 1657 * invocation of {@link SecurityManager#checkPackageAccess 1658 * s.checkPackageAccess()} denies access to the package 1659 * of this class 1660 * 1661 * </ul> 1662 * 1663 * @since JDK1.1 1664 */ 1665 public Constructor<T> getConstructor(Class<?>... parameterTypes) 1666 throws NoSuchMethodException, SecurityException { 1667 // be very careful not to change the stack depth of this 1668 // checkMemberAccess call for security reasons 1669 // see java.lang.SecurityManager.checkMemberAccess 1670 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader()); 1671 return getConstructor0(parameterTypes, Member.PUBLIC); 1672 } 1673 1674 1675 /** 1676 * Returns an array of {@code Class} objects reflecting all the 1677 * classes and interfaces declared as members of the class represented by 1678 * this {@code Class} object. This includes public, protected, default 1679 * (package) access, and private classes and interfaces declared by the 1680 * class, but excludes inherited classes and interfaces. This method 1681 * returns an array of length 0 if the class declares no classes or 1682 * interfaces as members, or if this {@code Class} object represents a 1683 * primitive type, an array class, or void. 1684 * 1685 * @return the array of {@code Class} objects representing all the 1686 * declared members of this class 1687 * @exception SecurityException 1688 * If a security manager, <i>s</i>, is present and any of the 1689 * following conditions is met: 1690 * 1691 * <ul> 1692 * 1693 * <li> invocation of 1694 * {@link SecurityManager#checkMemberAccess 1695 * s.checkMemberAccess(this, Member.DECLARED)} denies 1696 * access to the declared classes within this class 1697 * 1698 * <li> the caller's class loader is not the same as or an 1699 * ancestor of the class loader for the current class and 1700 * invocation of {@link SecurityManager#checkPackageAccess 1701 * s.checkPackageAccess()} denies access to the package 1702 * of this class 1703 * 1704 * </ul> 1705 * 1706 * @since JDK1.1 1707 */ 1708 public Class<?>[] getDeclaredClasses() throws SecurityException { 1709 // be very careful not to change the stack depth of this 1710 // checkMemberAccess call for security reasons 1711 // see java.lang.SecurityManager.checkMemberAccess 1712 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader()); 1713 return getDeclaredClasses0(); 1714 } 1715 1716 1717 /** 1718 * Returns an array of {@code Field} objects reflecting all the fields 1719 * declared by the class or interface represented by this 1720 * {@code Class} object. This includes public, protected, default 1721 * (package) access, and private fields, but excludes inherited fields. 1722 * The elements in the array returned are not sorted and are not in any 1723 * particular order. This method returns an array of length 0 if the class 1724 * or interface declares no fields, or if this {@code Class} object 1725 * represents a primitive type, an array class, or void. 1726 * 1727 * <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.3. 1728 * 1729 * @return the array of {@code Field} objects representing all the 1730 * declared fields of this class 1731 * @exception SecurityException 1732 * If a security manager, <i>s</i>, is present and any of the 1733 * following conditions is met: 1734 * 1735 * <ul> 1736 * 1737 * <li> invocation of 1738 * {@link SecurityManager#checkMemberAccess 1739 * s.checkMemberAccess(this, Member.DECLARED)} denies 1740 * access to the declared fields within this class 1741 * 1742 * <li> the caller's class loader is not the same as or an 1743 * ancestor of the class loader for the current class and 1744 * invocation of {@link SecurityManager#checkPackageAccess 1745 * s.checkPackageAccess()} denies access to the package 1746 * of this class 1747 * 1748 * </ul> 1749 * 1750 * @since JDK1.1 1751 */ 1752 public Field[] getDeclaredFields() throws SecurityException { 1753 // be very careful not to change the stack depth of this 1754 // checkMemberAccess call for security reasons 1755 // see java.lang.SecurityManager.checkMemberAccess 1756 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader()); 1757 return copyFields(privateGetDeclaredFields(false)); 1758 } 1759 1760 1761 /** 1762 * Returns an array of {@code Method} objects reflecting all the 1763 * methods declared by the class or interface represented by this 1764 * {@code Class} object. This includes public, protected, default 1765 * (package) access, and private methods, but excludes inherited methods. 1766 * The elements in the array returned are not sorted and are not in any 1767 * particular order. This method returns an array of length 0 if the class 1768 * or interface declares no methods, or if this {@code Class} object 1769 * represents a primitive type, an array class, or void. The class 1770 * initialization method {@code <clinit>} is not included in the 1771 * returned array. If the class declares multiple public member methods 1772 * with the same parameter types, they are all included in the returned 1773 * array. 1774 * 1775 * <p> See <em>The Java Language Specification</em>, section 8.2. 1776 * 1777 * @return the array of {@code Method} objects representing all the 1778 * declared methods of this class 1779 * @exception SecurityException 1780 * If a security manager, <i>s</i>, is present and any of the 1781 * following conditions is met: 1782 * 1783 * <ul> 1784 * 1785 * <li> invocation of 1786 * {@link SecurityManager#checkMemberAccess 1787 * s.checkMemberAccess(this, Member.DECLARED)} denies 1788 * access to the declared methods within this class 1789 * 1790 * <li> the caller's class loader is not the same as or an 1791 * ancestor of the class loader for the current class and 1792 * invocation of {@link SecurityManager#checkPackageAccess 1793 * s.checkPackageAccess()} denies access to the package 1794 * of this class 1795 * 1796 * </ul> 1797 * 1798 * @since JDK1.1 1799 */ 1800 public Method[] getDeclaredMethods() throws SecurityException { 1801 // be very careful not to change the stack depth of this 1802 // checkMemberAccess call for security reasons 1803 // see java.lang.SecurityManager.checkMemberAccess 1804 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader()); 1805 return copyMethods(privateGetDeclaredMethods(false)); 1806 } 1807 1808 1809 /** 1810 * Returns an array of {@code Constructor} objects reflecting all the 1811 * constructors declared by the class represented by this 1812 * {@code Class} object. These are public, protected, default 1813 * (package) access, and private constructors. The elements in the array 1814 * returned are not sorted and are not in any particular order. If the 1815 * class has a default constructor, it is included in the returned array. 1816 * This method returns an array of length 0 if this {@code Class} 1817 * object represents an interface, a primitive type, an array class, or 1818 * void. 1819 * 1820 * <p> See <em>The Java Language Specification</em>, section 8.2. 1821 * 1822 * @return the array of {@code Constructor} objects representing all the 1823 * declared constructors of this class 1824 * @exception SecurityException 1825 * If a security manager, <i>s</i>, is present and any of the 1826 * following conditions is met: 1827 * 1828 * <ul> 1829 * 1830 * <li> invocation of 1831 * {@link SecurityManager#checkMemberAccess 1832 * s.checkMemberAccess(this, Member.DECLARED)} denies 1833 * access to the declared constructors within this class 1834 * 1835 * <li> the caller's class loader is not the same as or an 1836 * ancestor of the class loader for the current class and 1837 * invocation of {@link SecurityManager#checkPackageAccess 1838 * s.checkPackageAccess()} denies access to the package 1839 * of this class 1840 * 1841 * </ul> 1842 * 1843 * @since JDK1.1 1844 */ 1845 public Constructor<?>[] getDeclaredConstructors() throws SecurityException { 1846 // be very careful not to change the stack depth of this 1847 // checkMemberAccess call for security reasons 1848 // see java.lang.SecurityManager.checkMemberAccess 1849 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader()); 1850 return copyConstructors(privateGetDeclaredConstructors(false)); 1851 } 1852 1853 1854 /** 1855 * Returns a {@code Field} object that reflects the specified declared 1856 * field of the class or interface represented by this {@code Class} 1857 * object. The {@code name} parameter is a {@code String} that 1858 * specifies the simple name of the desired field. Note that this method 1859 * will not reflect the {@code length} field of an array class. 1860 * 1861 * @param name the name of the field 1862 * @return the {@code Field} object for the specified field in this 1863 * class 1864 * @exception NoSuchFieldException if a field with the specified name is 1865 * not found. 1866 * @exception NullPointerException if {@code name} is {@code null} 1867 * @exception SecurityException 1868 * If a security manager, <i>s</i>, is present and any of the 1869 * following conditions is met: 1870 * 1871 * <ul> 1872 * 1873 * <li> invocation of 1874 * {@link SecurityManager#checkMemberAccess 1875 * s.checkMemberAccess(this, Member.DECLARED)} denies 1876 * access to the declared field 1877 * 1878 * <li> the caller's class loader is not the same as or an 1879 * ancestor of the class loader for the current class and 1880 * invocation of {@link SecurityManager#checkPackageAccess 1881 * s.checkPackageAccess()} denies access to the package 1882 * of this class 1883 * 1884 * </ul> 1885 * 1886 * @since JDK1.1 1887 */ 1888 public Field getDeclaredField(String name) 1889 throws NoSuchFieldException, SecurityException { 1890 // be very careful not to change the stack depth of this 1891 // checkMemberAccess call for security reasons 1892 // see java.lang.SecurityManager.checkMemberAccess 1893 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader()); 1894 Field field = searchFields(privateGetDeclaredFields(false), name); 1895 if (field == null) { 1896 throw new NoSuchFieldException(name); 1897 } 1898 return field; 1899 } 1900 1901 1902 /** 1903 * Returns a {@code Method} object that reflects the specified 1904 * declared method of the class or interface represented by this 1905 * {@code Class} object. The {@code name} parameter is a 1906 * {@code String} that specifies the simple name of the desired 1907 * method, and the {@code parameterTypes} parameter is an array of 1908 * {@code Class} objects that identify the method's formal parameter 1909 * types, in declared order. If more than one method with the same 1910 * parameter types is declared in a class, and one of these methods has a 1911 * return type that is more specific than any of the others, that method is 1912 * returned; otherwise one of the methods is chosen arbitrarily. If the 1913 * name is "<init>"or "<clinit>" a {@code NoSuchMethodException} 1914 * is raised. 1915 * 1916 * @param name the name of the method 1917 * @param parameterTypes the parameter array 1918 * @return the {@code Method} object for the method of this class 1919 * matching the specified name and parameters 1920 * @exception NoSuchMethodException if a matching method is not found. 1921 * @exception NullPointerException if {@code name} is {@code null} 1922 * @exception SecurityException 1923 * If a security manager, <i>s</i>, is present and any of the 1924 * following conditions is met: 1925 * 1926 * <ul> 1927 * 1928 * <li> invocation of 1929 * {@link SecurityManager#checkMemberAccess 1930 * s.checkMemberAccess(this, Member.DECLARED)} denies 1931 * access to the declared method 1932 * 1933 * <li> the caller's class loader is not the same as or an 1934 * ancestor of the class loader for the current class and 1935 * invocation of {@link SecurityManager#checkPackageAccess 1936 * s.checkPackageAccess()} denies access to the package 1937 * of this class 1938 * 1939 * </ul> 1940 * 1941 * @since JDK1.1 1942 */ 1943 public Method getDeclaredMethod(String name, Class<?>... parameterTypes) 1944 throws NoSuchMethodException, SecurityException { 1945 // be very careful not to change the stack depth of this 1946 // checkMemberAccess call for security reasons 1947 // see java.lang.SecurityManager.checkMemberAccess 1948 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader()); 1949 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes); 1950 if (method == null) { 1951 throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes)); 1952 } 1953 return method; 1954 } 1955 1956 1957 /** 1958 * Returns a {@code Constructor} object that reflects the specified 1959 * constructor of the class or interface represented by this 1960 * {@code Class} object. The {@code parameterTypes} parameter is 1961 * an array of {@code Class} objects that identify the constructor's 1962 * formal parameter types, in declared order. 1963 * 1964 * If this {@code Class} object represents an inner class 1965 * declared in a non-static context, the formal parameter types 1966 * include the explicit enclosing instance as the first parameter. 1967 * 1968 * @param parameterTypes the parameter array 1969 * @return The {@code Constructor} object for the constructor with the 1970 * specified parameter list 1971 * @exception NoSuchMethodException if a matching method is not found. 1972 * @exception SecurityException 1973 * If a security manager, <i>s</i>, is present and any of the 1974 * following conditions is met: 1975 * 1976 * <ul> 1977 * 1978 * <li> invocation of 1979 * {@link SecurityManager#checkMemberAccess 1980 * s.checkMemberAccess(this, Member.DECLARED)} denies 1981 * access to the declared constructor 1982 * 1983 * <li> the caller's class loader is not the same as or an 1984 * ancestor of the class loader for the current class and 1985 * invocation of {@link SecurityManager#checkPackageAccess 1986 * s.checkPackageAccess()} denies access to the package 1987 * of this class 1988 * 1989 * </ul> 1990 * 1991 * @since JDK1.1 1992 */ 1993 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes) 1994 throws NoSuchMethodException, SecurityException { 1995 // be very careful not to change the stack depth of this 1996 // checkMemberAccess call for security reasons 1997 // see java.lang.SecurityManager.checkMemberAccess 1998 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader()); 1999 return getConstructor0(parameterTypes, Member.DECLARED); 2000 } 2001 2002 /** 2003 * Finds a resource with a given name. The rules for searching resources 2004 * associated with a given class are implemented by the defining 2005 * {@linkplain ClassLoader class loader} of the class. This method 2006 * delegates to this object's class loader. If this object was loaded by 2007 * the bootstrap class loader, the method delegates to {@link 2008 * ClassLoader#getSystemResourceAsStream}. 2009 * 2010 * <p> Before delegation, an absolute resource name is constructed from the 2011 * given resource name using this algorithm: 2012 * 2013 * <ul> 2014 * 2015 * <li> If the {@code name} begins with a {@code '/'} 2016 * (<tt>'\u002f'</tt>), then the absolute name of the resource is the 2017 * portion of the {@code name} following the {@code '/'}. 2018 * 2019 * <li> Otherwise, the absolute name is of the following form: 2020 * 2021 * <blockquote> 2022 * {@code modified_package_name/name} 2023 * </blockquote> 2024 * 2025 * <p> Where the {@code modified_package_name} is the package name of this 2026 * object with {@code '/'} substituted for {@code '.'} 2027 * (<tt>'\u002e'</tt>). 2028 * 2029 * </ul> 2030 * 2031 * @param name name of the desired resource 2032 * @return A {@link java.io.InputStream} object or {@code null} if 2033 * no resource with this name is found 2034 * @throws NullPointerException If {@code name} is {@code null} 2035 * @since JDK1.1 2036 */ 2037 public InputStream getResourceAsStream(String name) { 2038 name = resolveName(name); 2039 ClassLoader cl = getClassLoader0(); 2040 if (cl==null) { 2041 // A system class. 2042 return ClassLoader.getSystemResourceAsStream(name); 2043 } 2044 return cl.getResourceAsStream(name); 2045 } 2046 2047 /** 2048 * Finds a resource with a given name. The rules for searching resources 2049 * associated with a given class are implemented by the defining 2050 * {@linkplain ClassLoader class loader} of the class. This method 2051 * delegates to this object's class loader. If this object was loaded by 2052 * the bootstrap class loader, the method delegates to {@link 2053 * ClassLoader#getSystemResource}. 2054 * 2055 * <p> Before delegation, an absolute resource name is constructed from the 2056 * given resource name using this algorithm: 2057 * 2058 * <ul> 2059 * 2060 * <li> If the {@code name} begins with a {@code '/'} 2061 * (<tt>'\u002f'</tt>), then the absolute name of the resource is the 2062 * portion of the {@code name} following the {@code '/'}. 2063 * 2064 * <li> Otherwise, the absolute name is of the following form: 2065 * 2066 * <blockquote> 2067 * {@code modified_package_name/name} 2068 * </blockquote> 2069 * 2070 * <p> Where the {@code modified_package_name} is the package name of this 2071 * object with {@code '/'} substituted for {@code '.'} 2072 * (<tt>'\u002e'</tt>). 2073 * 2074 * </ul> 2075 * 2076 * @param name name of the desired resource 2077 * @return A {@link java.net.URL} object or {@code null} if no 2078 * resource with this name is found 2079 * @since JDK1.1 2080 */ 2081 public java.net.URL getResource(String name) { 2082 name = resolveName(name); 2083 ClassLoader cl = getClassLoader0(); 2084 if (cl==null) { 2085 // A system class. 2086 return ClassLoader.getSystemResource(name); 2087 } 2088 return cl.getResource(name); 2089 } 2090 2091 2092 2093 /** protection domain returned when the internal domain is null */ 2094 private static java.security.ProtectionDomain allPermDomain; 2095 2096 2097 /** 2098 * Returns the {@code ProtectionDomain} of this class. If there is a 2099 * security manager installed, this method first calls the security 2100 * manager's {@code checkPermission} method with a 2101 * {@code RuntimePermission("getProtectionDomain")} permission to 2102 * ensure it's ok to get the 2103 * {@code ProtectionDomain}. 2104 * 2105 * @return the ProtectionDomain of this class 2106 * 2107 * @throws SecurityException 2108 * if a security manager exists and its 2109 * {@code checkPermission} method doesn't allow 2110 * getting the ProtectionDomain. 2111 * 2112 * @see java.security.ProtectionDomain 2113 * @see SecurityManager#checkPermission 2114 * @see java.lang.RuntimePermission 2115 * @since 1.2 2116 */ 2117 public java.security.ProtectionDomain getProtectionDomain() { 2118 SecurityManager sm = System.getSecurityManager(); 2119 if (sm != null) { 2120 sm.checkPermission(SecurityConstants.GET_PD_PERMISSION); 2121 } 2122 java.security.ProtectionDomain pd = getProtectionDomain0(); 2123 if (pd == null) { 2124 if (allPermDomain == null) { 2125 java.security.Permissions perms = 2126 new java.security.Permissions(); 2127 perms.add(SecurityConstants.ALL_PERMISSION); 2128 allPermDomain = 2129 new java.security.ProtectionDomain(null, perms); 2130 } 2131 pd = allPermDomain; 2132 } 2133 return pd; 2134 } 2135 2136 2137 /** 2138 * Returns the ProtectionDomain of this class. 2139 */ 2140 private native java.security.ProtectionDomain getProtectionDomain0(); 2141 2142 2143 /** 2144 * Set the ProtectionDomain for this class. Called by 2145 * ClassLoader.defineClass. 2146 */ 2147 native void setProtectionDomain0(java.security.ProtectionDomain pd); 2148 2149 2150 /* 2151 * Return the Virtual Machine's Class object for the named 2152 * primitive type. 2153 */ 2154 static native Class<?> getPrimitiveClass(String name); 2155 2156 2157 /* 2158 * Check if client is allowed to access members. If access is denied, 2159 * throw a SecurityException. 2160 * 2161 * Be very careful not to change the stack depth of this checkMemberAccess 2162 * call for security reasons. 2163 * See java.lang.SecurityManager.checkMemberAccess. 2164 * 2165 * <p> Default policy: allow all clients access with normal Java access 2166 * control. 2167 */ 2168 private void checkMemberAccess(int which, ClassLoader ccl) { 2169 SecurityManager s = System.getSecurityManager(); 2170 if (s != null) { 2171 s.checkMemberAccess(this, which); 2172 ClassLoader cl = getClassLoader0(); 2173 if ((ccl != null) && (ccl != cl) && 2174 ((cl == null) || !cl.isAncestor(ccl))) { 2175 String name = this.getName(); 2176 int i = name.lastIndexOf('.'); 2177 if (i != -1) { 2178 s.checkPackageAccess(name.substring(0, i)); 2179 } 2180 } 2181 } 2182 } 2183 2184 /** 2185 * Add a package name prefix if the name is not absolute Remove leading "/" 2186 * if name is absolute 2187 */ 2188 private String resolveName(String name) { 2189 if (name == null) { 2190 return name; 2191 } 2192 if (!name.startsWith("/")) { 2193 Class<?> c = this; 2194 while (c.isArray()) { 2195 c = c.getComponentType(); 2196 } 2197 String baseName = c.getName(); 2198 int index = baseName.lastIndexOf('.'); 2199 if (index != -1) { 2200 name = baseName.substring(0, index).replace('.', '/') 2201 +"/"+name; 2202 } 2203 } else { 2204 name = name.substring(1); 2205 } 2206 return name; 2207 } 2208 2209 /** 2210 * Reflection support. 2211 */ 2212 2213 // Caches for certain reflective results 2214 private static boolean useCaches = true; 2215 private volatile transient SoftReference<Field[]> declaredFields; 2216 private volatile transient SoftReference<Field[]> publicFields; 2217 private volatile transient SoftReference<Method[]> declaredMethods; 2218 private volatile transient SoftReference<Method[]> publicMethods; 2219 private volatile transient SoftReference<Constructor<T>[]> declaredConstructors; 2220 private volatile transient SoftReference<Constructor<T>[]> publicConstructors; 2221 // Intermediate results for getFields and getMethods 2222 private volatile transient SoftReference<Field[]> declaredPublicFields; 2223 private volatile transient SoftReference<Method[]> declaredPublicMethods; 2224 2225 // Incremented by the VM on each call to JVM TI RedefineClasses() 2226 // that redefines this class or a superclass. 2227 private volatile transient int classRedefinedCount = 0; 2228 2229 // Value of classRedefinedCount when we last cleared the cached values 2230 // that are sensitive to class redefinition. 2231 private volatile transient int lastRedefinedCount = 0; 2232 2233 // Clears cached values that might possibly have been obsoleted by 2234 // a class redefinition. 2235 private void clearCachesOnClassRedefinition() { 2236 if (lastRedefinedCount != classRedefinedCount) { 2237 declaredFields = publicFields = declaredPublicFields = null; 2238 declaredMethods = publicMethods = declaredPublicMethods = null; 2239 declaredConstructors = publicConstructors = null; 2240 annotations = declaredAnnotations = null; 2241 2242 // Use of "volatile" (and synchronization by caller in the case 2243 // of annotations) ensures that no thread sees the update to 2244 // lastRedefinedCount before seeing the caches cleared. 2245 // We do not guard against brief windows during which multiple 2246 // threads might redundantly work to fill an empty cache. 2247 lastRedefinedCount = classRedefinedCount; 2248 } 2249 } 2250 2251 // Generic signature handling 2252 private native String getGenericSignature(); 2253 2254 // Generic info repository; lazily initialized 2255 private transient ClassRepository genericInfo; 2256 2257 // accessor for factory 2258 private GenericsFactory getFactory() { 2259 // create scope and factory 2260 return CoreReflectionFactory.make(this, ClassScope.make(this)); 2261 } 2262 2263 // accessor for generic info repository 2264 private ClassRepository getGenericInfo() { 2265 // lazily initialize repository if necessary 2266 if (genericInfo == null) { 2267 // create and cache generic info repository 2268 genericInfo = ClassRepository.make(getGenericSignature(), 2269 getFactory()); 2270 } 2271 return genericInfo; //return cached repository 2272 } 2273 2274 // Annotations handling 2275 private native byte[] getRawAnnotations(); 2276 2277 native ConstantPool getConstantPool(); 2278 2279 // 2280 // 2281 // java.lang.reflect.Field handling 2282 // 2283 // 2284 2285 // Returns an array of "root" fields. These Field objects must NOT 2286 // be propagated to the outside world, but must instead be copied 2287 // via ReflectionFactory.copyField. 2288 private Field[] privateGetDeclaredFields(boolean publicOnly) { 2289 checkInitted(); 2290 Field[] res = null; 2291 if (useCaches) { 2292 clearCachesOnClassRedefinition(); 2293 if (publicOnly) { 2294 if (declaredPublicFields != null) { 2295 res = declaredPublicFields.get(); 2296 } 2297 } else { 2298 if (declaredFields != null) { 2299 res = declaredFields.get(); 2300 } 2301 } 2302 if (res != null) return res; 2303 } 2304 // No cached value available; request value from VM 2305 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly)); 2306 if (useCaches) { 2307 if (publicOnly) { 2308 declaredPublicFields = new SoftReference<>(res); 2309 } else { 2310 declaredFields = new SoftReference<>(res); 2311 } 2312 } 2313 return res; 2314 } 2315 2316 // Returns an array of "root" fields. These Field objects must NOT 2317 // be propagated to the outside world, but must instead be copied 2318 // via ReflectionFactory.copyField. 2319 private Field[] privateGetPublicFields(Set<Class<?>> traversedInterfaces) { 2320 checkInitted(); 2321 Field[] res = null; 2322 if (useCaches) { 2323 clearCachesOnClassRedefinition(); 2324 if (publicFields != null) { 2325 res = publicFields.get(); 2326 } 2327 if (res != null) return res; 2328 } 2329 2330 // No cached value available; compute value recursively. 2331 // Traverse in correct order for getField(). 2332 List<Field> fields = new ArrayList<>(); 2333 if (traversedInterfaces == null) { 2334 traversedInterfaces = new HashSet<>(); 2335 } 2336 2337 // Local fields 2338 Field[] tmp = privateGetDeclaredFields(true); 2339 addAll(fields, tmp); 2340 2341 // Direct superinterfaces, recursively 2342 for (Class<?> c : getInterfaces()) { 2343 if (!traversedInterfaces.contains(c)) { 2344 traversedInterfaces.add(c); 2345 addAll(fields, c.privateGetPublicFields(traversedInterfaces)); 2346 } 2347 } 2348 2349 // Direct superclass, recursively 2350 if (!isInterface()) { 2351 Class<?> c = getSuperclass(); 2352 if (c != null) { 2353 addAll(fields, c.privateGetPublicFields(traversedInterfaces)); 2354 } 2355 } 2356 2357 res = new Field[fields.size()]; 2358 fields.toArray(res); 2359 if (useCaches) { 2360 publicFields = new SoftReference<>(res); 2361 } 2362 return res; 2363 } 2364 2365 private static void addAll(Collection<Field> c, Field[] o) { 2366 for (int i = 0; i < o.length; i++) { 2367 c.add(o[i]); 2368 } 2369 } 2370 2371 2372 // 2373 // 2374 // java.lang.reflect.Constructor handling 2375 // 2376 // 2377 2378 // Returns an array of "root" constructors. These Constructor 2379 // objects must NOT be propagated to the outside world, but must 2380 // instead be copied via ReflectionFactory.copyConstructor. 2381 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) { 2382 checkInitted(); 2383 Constructor<T>[] res = null; 2384 if (useCaches) { 2385 clearCachesOnClassRedefinition(); 2386 if (publicOnly) { 2387 if (publicConstructors != null) { 2388 res = publicConstructors.get(); 2389 } 2390 } else { 2391 if (declaredConstructors != null) { 2392 res = declaredConstructors.get(); 2393 } 2394 } 2395 if (res != null) return res; 2396 } 2397 // No cached value available; request value from VM 2398 if (isInterface()) { 2399 @SuppressWarnings("unchecked") 2400 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0]; 2401 res = temporaryRes; 2402 } else { 2403 res = getDeclaredConstructors0(publicOnly); 2404 } 2405 if (useCaches) { 2406 if (publicOnly) { 2407 publicConstructors = new SoftReference<>(res); 2408 } else { 2409 declaredConstructors = new SoftReference<>(res); 2410 } 2411 } 2412 return res; 2413 } 2414 2415 // 2416 // 2417 // java.lang.reflect.Method handling 2418 // 2419 // 2420 2421 // Returns an array of "root" methods. These Method objects must NOT 2422 // be propagated to the outside world, but must instead be copied 2423 // via ReflectionFactory.copyMethod. 2424 private Method[] privateGetDeclaredMethods(boolean publicOnly) { 2425 checkInitted(); 2426 Method[] res = null; 2427 if (useCaches) { 2428 clearCachesOnClassRedefinition(); 2429 if (publicOnly) { 2430 if (declaredPublicMethods != null) { 2431 res = declaredPublicMethods.get(); 2432 } 2433 } else { 2434 if (declaredMethods != null) { 2435 res = declaredMethods.get(); 2436 } 2437 } 2438 if (res != null) return res; 2439 } 2440 // No cached value available; request value from VM 2441 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly)); 2442 if (useCaches) { 2443 if (publicOnly) { 2444 declaredPublicMethods = new SoftReference<>(res); 2445 } else { 2446 declaredMethods = new SoftReference<>(res); 2447 } 2448 } 2449 return res; 2450 } 2451 2452 static class MethodArray { 2453 private Method[] methods; 2454 private int length; 2455 2456 MethodArray() { 2457 methods = new Method[20]; 2458 length = 0; 2459 } 2460 2461 void add(Method m) { 2462 if (length == methods.length) { 2463 methods = Arrays.copyOf(methods, 2 * methods.length); 2464 } 2465 methods[length++] = m; 2466 } 2467 2468 void addAll(Method[] ma) { 2469 for (int i = 0; i < ma.length; i++) { 2470 add(ma[i]); 2471 } 2472 } 2473 2474 void addAll(MethodArray ma) { 2475 for (int i = 0; i < ma.length(); i++) { 2476 add(ma.get(i)); 2477 } 2478 } 2479 2480 void addIfNotPresent(Method newMethod) { 2481 for (int i = 0; i < length; i++) { 2482 Method m = methods[i]; 2483 if (m == newMethod || (m != null && m.equals(newMethod))) { 2484 return; 2485 } 2486 } 2487 add(newMethod); 2488 } 2489 2490 void addAllIfNotPresent(MethodArray newMethods) { 2491 for (int i = 0; i < newMethods.length(); i++) { 2492 Method m = newMethods.get(i); 2493 if (m != null) { 2494 addIfNotPresent(m); 2495 } 2496 } 2497 } 2498 2499 int length() { 2500 return length; 2501 } 2502 2503 Method get(int i) { 2504 return methods[i]; 2505 } 2506 2507 void removeByNameAndSignature(Method toRemove) { 2508 for (int i = 0; i < length; i++) { 2509 Method m = methods[i]; 2510 if (m != null && 2511 m.getReturnType() == toRemove.getReturnType() && 2512 m.getName() == toRemove.getName() && 2513 arrayContentsEq(m.getParameterTypes(), 2514 toRemove.getParameterTypes())) { 2515 methods[i] = null; 2516 } 2517 } 2518 } 2519 2520 void compactAndTrim() { 2521 int newPos = 0; 2522 // Get rid of null slots 2523 for (int pos = 0; pos < length; pos++) { 2524 Method m = methods[pos]; 2525 if (m != null) { 2526 if (pos != newPos) { 2527 methods[newPos] = m; 2528 } 2529 newPos++; 2530 } 2531 } 2532 if (newPos != methods.length) { 2533 methods = Arrays.copyOf(methods, newPos); 2534 } 2535 } 2536 2537 Method[] getArray() { 2538 return methods; 2539 } 2540 } 2541 2542 2543 // Returns an array of "root" methods. These Method objects must NOT 2544 // be propagated to the outside world, but must instead be copied 2545 // via ReflectionFactory.copyMethod. 2546 private Method[] privateGetPublicMethods() { 2547 checkInitted(); 2548 Method[] res = null; 2549 if (useCaches) { 2550 clearCachesOnClassRedefinition(); 2551 if (publicMethods != null) { 2552 res = publicMethods.get(); 2553 } 2554 if (res != null) return res; 2555 } 2556 2557 // No cached value available; compute value recursively. 2558 // Start by fetching public declared methods 2559 MethodArray methods = new MethodArray(); 2560 { 2561 Method[] tmp = privateGetDeclaredMethods(true); 2562 methods.addAll(tmp); 2563 } 2564 // Now recur over superclass and direct superinterfaces. 2565 // Go over superinterfaces first so we can more easily filter 2566 // out concrete implementations inherited from superclasses at 2567 // the end. 2568 MethodArray inheritedMethods = new MethodArray(); 2569 Class<?>[] interfaces = getInterfaces(); 2570 for (int i = 0; i < interfaces.length; i++) { 2571 inheritedMethods.addAll(interfaces[i].privateGetPublicMethods()); 2572 } 2573 if (!isInterface()) { 2574 Class<?> c = getSuperclass(); 2575 if (c != null) { 2576 MethodArray supers = new MethodArray(); 2577 supers.addAll(c.privateGetPublicMethods()); 2578 // Filter out concrete implementations of any 2579 // interface methods 2580 for (int i = 0; i < supers.length(); i++) { 2581 Method m = supers.get(i); 2582 if (m != null && !Modifier.isAbstract(m.getModifiers())) { 2583 inheritedMethods.removeByNameAndSignature(m); 2584 } 2585 } 2586 // Insert superclass's inherited methods before 2587 // superinterfaces' to satisfy getMethod's search 2588 // order 2589 supers.addAll(inheritedMethods); 2590 inheritedMethods = supers; 2591 } 2592 } 2593 // Filter out all local methods from inherited ones 2594 for (int i = 0; i < methods.length(); i++) { 2595 Method m = methods.get(i); 2596 inheritedMethods.removeByNameAndSignature(m); 2597 } 2598 methods.addAllIfNotPresent(inheritedMethods); 2599 methods.compactAndTrim(); 2600 res = methods.getArray(); 2601 if (useCaches) { 2602 publicMethods = new SoftReference<>(res); 2603 } 2604 return res; 2605 } 2606 2607 2608 // 2609 // Helpers for fetchers of one field, method, or constructor 2610 // 2611 2612 private Field searchFields(Field[] fields, String name) { 2613 String internedName = name.intern(); 2614 for (int i = 0; i < fields.length; i++) { 2615 if (fields[i].getName() == internedName) { 2616 return getReflectionFactory().copyField(fields[i]); 2617 } 2618 } 2619 return null; 2620 } 2621 2622 private Field getField0(String name) throws NoSuchFieldException { 2623 // Note: the intent is that the search algorithm this routine 2624 // uses be equivalent to the ordering imposed by 2625 // privateGetPublicFields(). It fetches only the declared 2626 // public fields for each class, however, to reduce the number 2627 // of Field objects which have to be created for the common 2628 // case where the field being requested is declared in the 2629 // class which is being queried. 2630 Field res = null; 2631 // Search declared public fields 2632 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) { 2633 return res; 2634 } 2635 // Direct superinterfaces, recursively 2636 Class<?>[] interfaces = getInterfaces(); 2637 for (int i = 0; i < interfaces.length; i++) { 2638 Class<?> c = interfaces[i]; 2639 if ((res = c.getField0(name)) != null) { 2640 return res; 2641 } 2642 } 2643 // Direct superclass, recursively 2644 if (!isInterface()) { 2645 Class<?> c = getSuperclass(); 2646 if (c != null) { 2647 if ((res = c.getField0(name)) != null) { 2648 return res; 2649 } 2650 } 2651 } 2652 return null; 2653 } 2654 2655 private static Method searchMethods(Method[] methods, 2656 String name, 2657 Class<?>[] parameterTypes) 2658 { 2659 Method res = null; 2660 String internedName = name.intern(); 2661 for (int i = 0; i < methods.length; i++) { 2662 Method m = methods[i]; 2663 if (m.getName() == internedName 2664 && arrayContentsEq(parameterTypes, m.getParameterTypes()) 2665 && (res == null 2666 || res.getReturnType().isAssignableFrom(m.getReturnType()))) 2667 res = m; 2668 } 2669 2670 return (res == null ? res : getReflectionFactory().copyMethod(res)); 2671 } 2672 2673 2674 private Method getMethod0(String name, Class<?>[] parameterTypes) { 2675 // Note: the intent is that the search algorithm this routine 2676 // uses be equivalent to the ordering imposed by 2677 // privateGetPublicMethods(). It fetches only the declared 2678 // public methods for each class, however, to reduce the 2679 // number of Method objects which have to be created for the 2680 // common case where the method being requested is declared in 2681 // the class which is being queried. 2682 Method res = null; 2683 // Search declared public methods 2684 if ((res = searchMethods(privateGetDeclaredMethods(true), 2685 name, 2686 parameterTypes)) != null) { 2687 return res; 2688 } 2689 // Search superclass's methods 2690 if (!isInterface()) { 2691 Class<? super T> c = getSuperclass(); 2692 if (c != null) { 2693 if ((res = c.getMethod0(name, parameterTypes)) != null) { 2694 return res; 2695 } 2696 } 2697 } 2698 // Search superinterfaces' methods 2699 Class<?>[] interfaces = getInterfaces(); 2700 for (int i = 0; i < interfaces.length; i++) { 2701 Class<?> c = interfaces[i]; 2702 if ((res = c.getMethod0(name, parameterTypes)) != null) { 2703 return res; 2704 } 2705 } 2706 // Not found 2707 return null; 2708 } 2709 2710 private Constructor<T> getConstructor0(Class<?>[] parameterTypes, 2711 int which) throws NoSuchMethodException 2712 { 2713 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC)); 2714 for (Constructor<T> constructor : constructors) { 2715 if (arrayContentsEq(parameterTypes, 2716 constructor.getParameterTypes())) { 2717 return getReflectionFactory().copyConstructor(constructor); 2718 } 2719 } 2720 throw new NoSuchMethodException(getName() + ".<init>" + argumentTypesToString(parameterTypes)); 2721 } 2722 2723 // 2724 // Other helpers and base implementation 2725 // 2726 2727 private static boolean arrayContentsEq(Object[] a1, Object[] a2) { 2728 if (a1 == null) { 2729 return a2 == null || a2.length == 0; 2730 } 2731 2732 if (a2 == null) { 2733 return a1.length == 0; 2734 } 2735 2736 if (a1.length != a2.length) { 2737 return false; 2738 } 2739 2740 for (int i = 0; i < a1.length; i++) { 2741 if (a1[i] != a2[i]) { 2742 return false; 2743 } 2744 } 2745 2746 return true; 2747 } 2748 2749 private static Field[] copyFields(Field[] arg) { 2750 Field[] out = new Field[arg.length]; 2751 ReflectionFactory fact = getReflectionFactory(); 2752 for (int i = 0; i < arg.length; i++) { 2753 out[i] = fact.copyField(arg[i]); 2754 } 2755 return out; 2756 } 2757 2758 private static Method[] copyMethods(Method[] arg) { 2759 Method[] out = new Method[arg.length]; 2760 ReflectionFactory fact = getReflectionFactory(); 2761 for (int i = 0; i < arg.length; i++) { 2762 out[i] = fact.copyMethod(arg[i]); 2763 } 2764 return out; 2765 } 2766 2767 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) { 2768 Constructor<U>[] out = arg.clone(); 2769 ReflectionFactory fact = getReflectionFactory(); 2770 for (int i = 0; i < out.length; i++) { 2771 out[i] = fact.copyConstructor(out[i]); 2772 } 2773 return out; 2774 } 2775 2776 private native Field[] getDeclaredFields0(boolean publicOnly); 2777 private native Method[] getDeclaredMethods0(boolean publicOnly); 2778 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly); 2779 private native Class<?>[] getDeclaredClasses0(); 2780 2781 private static String argumentTypesToString(Class<?>[] argTypes) { 2782 StringBuilder buf = new StringBuilder(); 2783 buf.append("("); 2784 if (argTypes != null) { 2785 for (int i = 0; i < argTypes.length; i++) { 2786 if (i > 0) { 2787 buf.append(", "); 2788 } 2789 Class<?> c = argTypes[i]; 2790 buf.append((c == null) ? "null" : c.getName()); 2791 } 2792 } 2793 buf.append(")"); 2794 return buf.toString(); 2795 } 2796 2797 /** use serialVersionUID from JDK 1.1 for interoperability */ 2798 private static final long serialVersionUID = 3206093459760846163L; 2799 2800 2801 /** 2802 * Class Class is special cased within the Serialization Stream Protocol. 2803 * 2804 * A Class instance is written initially into an ObjectOutputStream in the 2805 * following format: 2806 * <pre> 2807 * {@code TC_CLASS} ClassDescriptor 2808 * A ClassDescriptor is a special cased serialization of 2809 * a {@code java.io.ObjectStreamClass} instance. 2810 * </pre> 2811 * A new handle is generated for the initial time the class descriptor 2812 * is written into the stream. Future references to the class descriptor 2813 * are written as references to the initial class descriptor instance. 2814 * 2815 * @see java.io.ObjectStreamClass 2816 */ 2817 private static final ObjectStreamField[] serialPersistentFields = 2818 new ObjectStreamField[0]; 2819 2820 2821 /** 2822 * Returns the assertion status that would be assigned to this 2823 * class if it were to be initialized at the time this method is invoked. 2824 * If this class has had its assertion status set, the most recent 2825 * setting will be returned; otherwise, if any package default assertion 2826 * status pertains to this class, the most recent setting for the most 2827 * specific pertinent package default assertion status is returned; 2828 * otherwise, if this class is not a system class (i.e., it has a 2829 * class loader) its class loader's default assertion status is returned; 2830 * otherwise, the system class default assertion status is returned. 2831 * <p> 2832 * Few programmers will have any need for this method; it is provided 2833 * for the benefit of the JRE itself. (It allows a class to determine at 2834 * the time that it is initialized whether assertions should be enabled.) 2835 * Note that this method is not guaranteed to return the actual 2836 * assertion status that was (or will be) associated with the specified 2837 * class when it was (or will be) initialized. 2838 * 2839 * @return the desired assertion status of the specified class. 2840 * @see java.lang.ClassLoader#setClassAssertionStatus 2841 * @see java.lang.ClassLoader#setPackageAssertionStatus 2842 * @see java.lang.ClassLoader#setDefaultAssertionStatus 2843 * @since 1.4 2844 */ 2845 public boolean desiredAssertionStatus() { 2846 ClassLoader loader = getClassLoader(); 2847 // If the loader is null this is a system class, so ask the VM 2848 if (loader == null) 2849 return desiredAssertionStatus0(this); 2850 2851 // If the classloader has been initialized with the assertion 2852 // directives, ask it. Otherwise, ask the VM. 2853 synchronized(loader.assertionLock) { 2854 if (loader.classAssertionStatus != null) { 2855 return loader.desiredAssertionStatus(getName()); 2856 } 2857 } 2858 return desiredAssertionStatus0(this); 2859 } 2860 2861 // Retrieves the desired assertion status of this class from the VM 2862 private static native boolean desiredAssertionStatus0(Class<?> clazz); 2863 2864 /** 2865 * Returns true if and only if this class was declared as an enum in the 2866 * source code. 2867 * 2868 * @return true if and only if this class was declared as an enum in the 2869 * source code 2870 * @since 1.5 2871 */ 2872 public boolean isEnum() { 2873 // An enum must both directly extend java.lang.Enum and have 2874 // the ENUM bit set; classes for specialized enum constants 2875 // don't do the former. 2876 return (this.getModifiers() & ENUM) != 0 && 2877 this.getSuperclass() == java.lang.Enum.class; 2878 } 2879 2880 // Fetches the factory for reflective objects 2881 private static ReflectionFactory getReflectionFactory() { 2882 if (reflectionFactory == null) { 2883 reflectionFactory = 2884 java.security.AccessController.doPrivileged 2885 (new sun.reflect.ReflectionFactory.GetReflectionFactoryAction()); 2886 } 2887 return reflectionFactory; 2888 } 2889 private static ReflectionFactory reflectionFactory; 2890 2891 // To be able to query system properties as soon as they're available 2892 private static boolean initted = false; 2893 private static void checkInitted() { 2894 if (initted) return; 2895 AccessController.doPrivileged(new PrivilegedAction<Void>() { 2896 public Void run() { 2897 // Tests to ensure the system properties table is fully 2898 // initialized. This is needed because reflection code is 2899 // called very early in the initialization process (before 2900 // command-line arguments have been parsed and therefore 2901 // these user-settable properties installed.) We assume that 2902 // if System.out is non-null then the System class has been 2903 // fully initialized and that the bulk of the startup code 2904 // has been run. 2905 2906 if (System.out == null) { 2907 // java.lang.System not yet fully initialized 2908 return null; 2909 } 2910 2911 // Doesn't use Boolean.getBoolean to avoid class init. 2912 String val = 2913 System.getProperty("sun.reflect.noCaches"); 2914 if (val != null && val.equals("true")) { 2915 useCaches = false; 2916 } 2917 2918 initted = true; 2919 return null; 2920 } 2921 }); 2922 } 2923 2924 /** 2925 * Returns the elements of this enum class or null if this 2926 * Class object does not represent an enum type. 2927 * 2928 * @return an array containing the values comprising the enum class 2929 * represented by this Class object in the order they're 2930 * declared, or null if this Class object does not 2931 * represent an enum type 2932 * @since 1.5 2933 */ 2934 public T[] getEnumConstants() { 2935 T[] values = getEnumConstantsShared(); 2936 return (values != null) ? values.clone() : null; 2937 } 2938 2939 /** 2940 * Returns the elements of this enum class or null if this 2941 * Class object does not represent an enum type; 2942 * identical to getEnumConstants except that the result is 2943 * uncloned, cached, and shared by all callers. 2944 */ 2945 T[] getEnumConstantsShared() { 2946 if (enumConstants == null) { 2947 if (!isEnum()) return null; 2948 try { 2949 final Method values = getMethod("values"); 2950 java.security.AccessController.doPrivileged( 2951 new java.security.PrivilegedAction<Void>() { 2952 public Void run() { 2953 values.setAccessible(true); 2954 return null; 2955 } 2956 }); 2957 @SuppressWarnings("unchecked") 2958 T[] temporaryConstants = (T[])values.invoke(null); 2959 enumConstants = temporaryConstants; 2960 } 2961 // These can happen when users concoct enum-like classes 2962 // that don't comply with the enum spec. 2963 catch (InvocationTargetException | NoSuchMethodException | 2964 IllegalAccessException ex) { return null; } 2965 } 2966 return enumConstants; 2967 } 2968 private volatile transient T[] enumConstants = null; 2969 2970 /** 2971 * Returns a map from simple name to enum constant. This package-private 2972 * method is used internally by Enum to implement 2973 * public static <T extends Enum<T>> T valueOf(Class<T>, String) 2974 * efficiently. Note that the map is returned by this method is 2975 * created lazily on first use. Typically it won't ever get created. 2976 */ 2977 Map<String, T> enumConstantDirectory() { 2978 if (enumConstantDirectory == null) { 2979 T[] universe = getEnumConstantsShared(); 2980 if (universe == null) 2981 throw new IllegalArgumentException( 2982 getName() + " is not an enum type"); 2983 Map<String, T> m = new HashMap<>(2 * universe.length); 2984 for (T constant : universe) 2985 m.put(((Enum<?>)constant).name(), constant); 2986 enumConstantDirectory = m; 2987 } 2988 return enumConstantDirectory; 2989 } 2990 private volatile transient Map<String, T> enumConstantDirectory = null; 2991 2992 /** 2993 * Casts an object to the class or interface represented 2994 * by this {@code Class} object. 2995 * 2996 * @param obj the object to be cast 2997 * @return the object after casting, or null if obj is null 2998 * 2999 * @throws ClassCastException if the object is not 3000 * null and is not assignable to the type T. 3001 * 3002 * @since 1.5 3003 */ 3004 @SuppressWarnings("unchecked") 3005 public T cast(Object obj) { 3006 if (obj != null && !isInstance(obj)) 3007 throw new ClassCastException(cannotCastMsg(obj)); 3008 return (T) obj; 3009 } 3010 3011 private String cannotCastMsg(Object obj) { 3012 return "Cannot cast " + obj.getClass().getName() + " to " + getName(); 3013 } 3014 3015 /** 3016 * Casts this {@code Class} object to represent a subclass of the class 3017 * represented by the specified class object. Checks that the cast 3018 * is valid, and throws a {@code ClassCastException} if it is not. If 3019 * this method succeeds, it always returns a reference to this class object. 3020 * 3021 * <p>This method is useful when a client needs to "narrow" the type of 3022 * a {@code Class} object to pass it to an API that restricts the 3023 * {@code Class} objects that it is willing to accept. A cast would 3024 * generate a compile-time warning, as the correctness of the cast 3025 * could not be checked at runtime (because generic types are implemented 3026 * by erasure). 3027 * 3028 * @return this {@code Class} object, cast to represent a subclass of 3029 * the specified class object. 3030 * @throws ClassCastException if this {@code Class} object does not 3031 * represent a subclass of the specified class (here "subclass" includes 3032 * the class itself). 3033 * @since 1.5 3034 */ 3035 @SuppressWarnings("unchecked") 3036 public <U> Class<? extends U> asSubclass(Class<U> clazz) { 3037 if (clazz.isAssignableFrom(this)) 3038 return (Class<? extends U>) this; 3039 else 3040 throw new ClassCastException(this.toString()); 3041 } 3042 3043 /** 3044 * @throws NullPointerException {@inheritDoc} 3045 * @since 1.5 3046 */ 3047 @SuppressWarnings("unchecked") 3048 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) { 3049 if (annotationClass == null) 3050 throw new NullPointerException(); 3051 3052 initAnnotationsIfNecessary(); 3053 return (A) annotations.get(annotationClass); 3054 } 3055 3056 /** 3057 * @throws NullPointerException {@inheritDoc} 3058 * @since 1.5 3059 */ 3060 public boolean isAnnotationPresent( 3061 Class<? extends Annotation> annotationClass) { 3062 if (annotationClass == null) 3063 throw new NullPointerException(); 3064 3065 return getAnnotation(annotationClass) != null; 3066 } 3067 3068 3069 /** 3070 * @since 1.5 3071 */ 3072 public Annotation[] getAnnotations() { 3073 initAnnotationsIfNecessary(); 3074 return AnnotationParser.toArray(annotations); 3075 } 3076 3077 /** 3078 * @since 1.5 3079 */ 3080 public Annotation[] getDeclaredAnnotations() { 3081 initAnnotationsIfNecessary(); 3082 return AnnotationParser.toArray(declaredAnnotations); 3083 } 3084 3085 // Annotations cache 3086 private transient Map<Class<? extends Annotation>, Annotation> annotations; 3087 private transient Map<Class<? extends Annotation>, Annotation> declaredAnnotations; 3088 3089 private synchronized void initAnnotationsIfNecessary() { 3090 clearCachesOnClassRedefinition(); 3091 if (annotations != null) 3092 return; 3093 declaredAnnotations = AnnotationParser.parseAnnotations( 3094 getRawAnnotations(), getConstantPool(), this); 3095 Class<?> superClass = getSuperclass(); 3096 if (superClass == null) { 3097 annotations = declaredAnnotations; 3098 } else { 3099 annotations = new HashMap<>(); 3100 superClass.initAnnotationsIfNecessary(); 3101 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superClass.annotations.entrySet()) { 3102 Class<? extends Annotation> annotationClass = e.getKey(); 3103 if (AnnotationType.getInstance(annotationClass).isInherited()) 3104 annotations.put(annotationClass, e.getValue()); 3105 } 3106 annotations.putAll(declaredAnnotations); 3107 } 3108 } 3109 3110 // Annotation types cache their internal (AnnotationType) form 3111 3112 private AnnotationType annotationType; 3113 3114 void setAnnotationType(AnnotationType type) { 3115 annotationType = type; 3116 } 3117 3118 AnnotationType getAnnotationType() { 3119 return annotationType; 3120 } 3121 3122 /* Backing store of user-defined values pertaining to this class. 3123 * Maintained by the ClassValue class. 3124 */ 3125 transient ClassValue.ClassValueMap classValueMap; 3126 }