1 /* 2 * Copyright 1996-2006 Sun Microsystems, Inc. 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. Sun designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 22 * CA 95054 USA or visit www.sun.com if you need additional information or 23 * have any questions. 24 */ 25 26 package java.lang.reflect; 27 28 import sun.reflect.FieldAccessor; 29 import sun.reflect.Reflection; 30 import sun.reflect.generics.repository.FieldRepository; 31 import sun.reflect.generics.factory.CoreReflectionFactory; 32 import sun.reflect.generics.factory.GenericsFactory; 33 import sun.reflect.generics.scope.ClassScope; 34 import java.lang.annotation.Annotation; 35 import java.util.Map; 36 import sun.reflect.annotation.AnnotationParser; 37 38 39 /** 40 * A {@code Field} provides information about, and dynamic access to, a 41 * single field of a class or an interface. The reflected field may 42 * be a class (static) field or an instance field. 43 * 44 * <p>A {@code Field} permits widening conversions to occur during a get or 45 * set access operation, but throws an {@code IllegalArgumentException} if a 46 * narrowing conversion would occur. 47 * 48 * @see Member 49 * @see java.lang.Class 50 * @see java.lang.Class#getFields() 51 * @see java.lang.Class#getField(String) 52 * @see java.lang.Class#getDeclaredFields() 53 * @see java.lang.Class#getDeclaredField(String) 54 * 55 * @author Kenneth Russell 56 * @author Nakul Saraiya 57 */ 58 public final 59 class Field extends AccessibleObject implements Member { 60 61 private Class<?> clazz; 62 private int slot; 63 // This is guaranteed to be interned by the VM in the 1.4 64 // reflection implementation 65 private String name; 66 private Class<?> type; 67 private int modifiers; 68 // Generics and annotations support 69 private transient String signature; 70 // generic info repository; lazily initialized 71 private transient FieldRepository genericInfo; 72 private byte[] annotations; 73 // Cached field accessor created without override 74 private FieldAccessor fieldAccessor; 75 // Cached field accessor created with override 76 private FieldAccessor overrideFieldAccessor; 77 // For sharing of FieldAccessors. This branching structure is 78 // currently only two levels deep (i.e., one root Field and 79 // potentially many Field objects pointing to it.) 80 private Field root; 81 82 // More complicated security check cache needed here than for 83 // Class.newInstance() and Constructor.newInstance() 84 private Class<?> securityCheckCache; 85 private Class<?> securityCheckTargetClassCache; 86 87 // Generics infrastructure 88 89 private String getGenericSignature() {return signature;} 90 91 // Accessor for factory 92 private GenericsFactory getFactory() { 93 Class<?> c = getDeclaringClass(); 94 // create scope and factory 95 return CoreReflectionFactory.make(c, ClassScope.make(c)); 96 } 97 98 // Accessor for generic info repository 99 private FieldRepository getGenericInfo() { 100 // lazily initialize repository if necessary 101 if (genericInfo == null) { 102 // create and cache generic info repository 103 genericInfo = FieldRepository.make(getGenericSignature(), 104 getFactory()); 105 } 106 return genericInfo; //return cached repository 107 } 108 109 110 /** 111 * Package-private constructor used by ReflectAccess to enable 112 * instantiation of these objects in Java code from the java.lang 113 * package via sun.reflect.LangReflectAccess. 114 */ 115 Field(Class<?> declaringClass, 116 String name, 117 Class<?> type, 118 int modifiers, 119 int slot, 120 String signature, 121 byte[] annotations) 122 { 123 this.clazz = declaringClass; 124 this.name = name; 125 this.type = type; 126 this.modifiers = modifiers; 127 this.slot = slot; 128 this.signature = signature; 129 this.annotations = annotations; 130 } 131 132 /** 133 * Package-private routine (exposed to java.lang.Class via 134 * ReflectAccess) which returns a copy of this Field. The copy's 135 * "root" field points to this Field. 136 */ 137 Field copy() { 138 // This routine enables sharing of FieldAccessor objects 139 // among Field objects which refer to the same underlying 140 // method in the VM. (All of this contortion is only necessary 141 // because of the "accessibility" bit in AccessibleObject, 142 // which implicitly requires that new java.lang.reflect 143 // objects be fabricated for each reflective call on Class 144 // objects.) 145 Field res = new Field(clazz, name, type, modifiers, slot, signature, annotations); 146 res.root = this; 147 // Might as well eagerly propagate this if already present 148 res.fieldAccessor = fieldAccessor; 149 res.overrideFieldAccessor = overrideFieldAccessor; 150 return res; 151 } 152 153 /** 154 * Returns the {@code Class} object representing the class or interface 155 * that declares the field represented by this {@code Field} object. 156 */ 157 public Class<?> getDeclaringClass() { 158 return clazz; 159 } 160 161 /** 162 * Returns the name of the field represented by this {@code Field} object. 163 */ 164 public String getName() { 165 return name; 166 } 167 168 /** 169 * Returns the Java language modifiers for the field represented 170 * by this {@code Field} object, as an integer. The {@code Modifier} class should 171 * be used to decode the modifiers. 172 * 173 * @see Modifier 174 */ 175 public int getModifiers() { 176 return modifiers; 177 } 178 179 /** 180 * Returns {@code true} if this field represents an element of 181 * an enumerated type; returns {@code false} otherwise. 182 * 183 * @return {@code true} if and only if this field represents an element of 184 * an enumerated type. 185 * @since 1.5 186 */ 187 public boolean isEnumConstant() { 188 return (getModifiers() & Modifier.ENUM) != 0; 189 } 190 191 /** 192 * Returns {@code true} if this field is a synthetic 193 * field; returns {@code false} otherwise. 194 * 195 * @return true if and only if this field is a synthetic 196 * field as defined by the Java Language Specification. 197 * @since 1.5 198 */ 199 public boolean isSynthetic() { 200 return Modifier.isSynthetic(getModifiers()); 201 } 202 203 /** 204 * Returns a {@code Class} object that identifies the 205 * declared type for the field represented by this 206 * {@code Field} object. 207 * 208 * @return a {@code Class} object identifying the declared 209 * type of the field represented by this object 210 */ 211 public Class<?> getType() { 212 return type; 213 } 214 215 /** 216 * Returns a {@code Type} object that represents the declared type for 217 * the field represented by this {@code Field} object. 218 * 219 * <p>If the {@code Type} is a parameterized type, the 220 * {@code Type} object returned must accurately reflect the 221 * actual type parameters used in the source code. 222 * 223 * <p>If the type of the underlying field is a type variable or a 224 * parameterized type, it is created. Otherwise, it is resolved. 225 * 226 * @return a {@code Type} object that represents the declared type for 227 * the field represented by this {@code Field} object 228 * @throws GenericSignatureFormatError if the generic field 229 * signature does not conform to the format specified in the Java 230 * Virtual Machine Specification, 3rd edition 231 * @throws TypeNotPresentException if the generic type 232 * signature of the underlying field refers to a non-existent 233 * type declaration 234 * @throws MalformedParameterizedTypeException if the generic 235 * signature of the underlying field refers to a parameterized type 236 * that cannot be instantiated for any reason 237 * @since 1.5 238 */ 239 public Type getGenericType() { 240 if (getGenericSignature() != null) 241 return getGenericInfo().getGenericType(); 242 else 243 return getType(); 244 } 245 246 247 /** 248 * Compares this {@code Field} against the specified object. Returns 249 * true if the objects are the same. Two {@code Field} objects are the same if 250 * they were declared by the same class and have the same name 251 * and type. 252 */ 253 public boolean equals(Object obj) { 254 if (obj != null && obj instanceof Field) { 255 Field other = (Field)obj; 256 return (getDeclaringClass() == other.getDeclaringClass()) 257 && (getName() == other.getName()) 258 && (getType() == other.getType()); 259 } 260 return false; 261 } 262 263 /** 264 * Returns a hashcode for this {@code Field}. This is computed as the 265 * exclusive-or of the hashcodes for the underlying field's 266 * declaring class name and its name. 267 */ 268 public int hashCode() { 269 return getDeclaringClass().getName().hashCode() ^ getName().hashCode(); 270 } 271 272 /** 273 * Returns a string describing this {@code Field}. The format is 274 * the access modifiers for the field, if any, followed 275 * by the field type, followed by a space, followed by 276 * the fully-qualified name of the class declaring the field, 277 * followed by a period, followed by the name of the field. 278 * For example: 279 * <pre> 280 * public static final int java.lang.Thread.MIN_PRIORITY 281 * private int java.io.FileDescriptor.fd 282 * </pre> 283 * 284 * <p>The modifiers are placed in canonical order as specified by 285 * "The Java Language Specification". This is {@code public}, 286 * {@code protected} or {@code private} first, and then other 287 * modifiers in the following order: {@code static}, {@code final}, 288 * {@code transient}, {@code volatile}. 289 */ 290 public String toString() { 291 int mod = getModifiers(); 292 return (((mod == 0) ? "" : (Modifier.toString(mod) + " ")) 293 + getTypeName(getType()) + " " 294 + getTypeName(getDeclaringClass()) + "." 295 + getName()); 296 } 297 298 /** 299 * Returns a string describing this {@code Field}, including 300 * its generic type. The format is the access modifiers for the 301 * field, if any, followed by the generic field type, followed by 302 * a space, followed by the fully-qualified name of the class 303 * declaring the field, followed by a period, followed by the name 304 * of the field. 305 * 306 * <p>The modifiers are placed in canonical order as specified by 307 * "The Java Language Specification". This is {@code public}, 308 * {@code protected} or {@code private} first, and then other 309 * modifiers in the following order: {@code static}, {@code final}, 310 * {@code transient}, {@code volatile}. 311 * 312 * @return a string describing this {@code Field}, including 313 * its generic type 314 * 315 * @since 1.5 316 */ 317 public String toGenericString() { 318 int mod = getModifiers(); 319 Type fieldType = getGenericType(); 320 return (((mod == 0) ? "" : (Modifier.toString(mod) + " ")) 321 + ((fieldType instanceof Class) ? 322 getTypeName((Class)fieldType): fieldType.toString())+ " " 323 + getTypeName(getDeclaringClass()) + "." 324 + getName()); 325 } 326 327 /** 328 * Returns the value of the field represented by this {@code Field}, on 329 * the specified object. The value is automatically wrapped in an 330 * object if it has a primitive type. 331 * 332 * <p>The underlying field's value is obtained as follows: 333 * 334 * <p>If the underlying field is a static field, the {@code obj} argument 335 * is ignored; it may be null. 336 * 337 * <p>Otherwise, the underlying field is an instance field. If the 338 * specified {@code obj} argument is null, the method throws a 339 * {@code NullPointerException}. If the specified object is not an 340 * instance of the class or interface declaring the underlying 341 * field, the method throws an {@code IllegalArgumentException}. 342 * 343 * <p>If this {@code Field} object enforces Java language access control, and 344 * the underlying field is inaccessible, the method throws an 345 * {@code IllegalAccessException}. 346 * If the underlying field is static, the class that declared the 347 * field is initialized if it has not already been initialized. 348 * 349 * <p>Otherwise, the value is retrieved from the underlying instance 350 * or static field. If the field has a primitive type, the value 351 * is wrapped in an object before being returned, otherwise it is 352 * returned as is. 353 * 354 * <p>If the field is hidden in the type of {@code obj}, 355 * the field's value is obtained according to the preceding rules. 356 * 357 * @param obj object from which the represented field's value is 358 * to be extracted 359 * @return the value of the represented field in object 360 * {@code obj}; primitive values are wrapped in an appropriate 361 * object before being returned 362 * 363 * @exception IllegalAccessException if the underlying field 364 * is inaccessible. 365 * @exception IllegalArgumentException if the specified object is not an 366 * instance of the class or interface declaring the underlying 367 * field (or a subclass or implementor thereof). 368 * @exception NullPointerException if the specified object is null 369 * and the field is an instance field. 370 * @exception ExceptionInInitializerError if the initialization provoked 371 * by this method fails. 372 */ 373 public Object get(Object obj) 374 throws IllegalArgumentException, IllegalAccessException 375 { 376 return getFieldAccessor(obj).get(obj); 377 } 378 379 /** 380 * Gets the value of a static or instance {@code boolean} field. 381 * 382 * @param obj the object to extract the {@code boolean} value 383 * from 384 * @return the value of the {@code boolean} field 385 * 386 * @exception IllegalAccessException if the underlying field 387 * is inaccessible. 388 * @exception IllegalArgumentException if the specified object is not 389 * an instance of the class or interface declaring the 390 * underlying field (or a subclass or implementor 391 * thereof), or if the field value cannot be 392 * converted to the type {@code boolean} by a 393 * widening conversion. 394 * @exception NullPointerException if the specified object is null 395 * and the field is an instance field. 396 * @exception ExceptionInInitializerError if the initialization provoked 397 * by this method fails. 398 * @see Field#get 399 */ 400 public boolean getBoolean(Object obj) 401 throws IllegalArgumentException, IllegalAccessException 402 { 403 return getFieldAccessor(obj).getBoolean(obj); 404 } 405 406 /** 407 * Gets the value of a static or instance {@code byte} field. 408 * 409 * @param obj the object to extract the {@code byte} value 410 * from 411 * @return the value of the {@code byte} field 412 * 413 * @exception IllegalAccessException if the underlying field 414 * is inaccessible. 415 * @exception IllegalArgumentException if the specified object is not 416 * an instance of the class or interface declaring the 417 * underlying field (or a subclass or implementor 418 * thereof), or if the field value cannot be 419 * converted to the type {@code byte} by a 420 * widening conversion. 421 * @exception NullPointerException if the specified object is null 422 * and the field is an instance field. 423 * @exception ExceptionInInitializerError if the initialization provoked 424 * by this method fails. 425 * @see Field#get 426 */ 427 public byte getByte(Object obj) 428 throws IllegalArgumentException, IllegalAccessException 429 { 430 return getFieldAccessor(obj).getByte(obj); 431 } 432 433 /** 434 * Gets the value of a static or instance field of type 435 * {@code char} or of another primitive type convertible to 436 * type {@code char} via a widening conversion. 437 * 438 * @param obj the object to extract the {@code char} value 439 * from 440 * @return the value of the field converted to type {@code char} 441 * 442 * @exception IllegalAccessException if the underlying field 443 * is inaccessible. 444 * @exception IllegalArgumentException if the specified object is not 445 * an instance of the class or interface declaring the 446 * underlying field (or a subclass or implementor 447 * thereof), or if the field value cannot be 448 * converted to the type {@code char} by a 449 * widening conversion. 450 * @exception NullPointerException if the specified object is null 451 * and the field is an instance field. 452 * @exception ExceptionInInitializerError if the initialization provoked 453 * by this method fails. 454 * @see Field#get 455 */ 456 public char getChar(Object obj) 457 throws IllegalArgumentException, IllegalAccessException 458 { 459 return getFieldAccessor(obj).getChar(obj); 460 } 461 462 /** 463 * Gets the value of a static or instance field of type 464 * {@code short} or of another primitive type convertible to 465 * type {@code short} via a widening conversion. 466 * 467 * @param obj the object to extract the {@code short} value 468 * from 469 * @return the value of the field converted to type {@code short} 470 * 471 * @exception IllegalAccessException if the underlying field 472 * is inaccessible. 473 * @exception IllegalArgumentException if the specified object is not 474 * an instance of the class or interface declaring the 475 * underlying field (or a subclass or implementor 476 * thereof), or if the field value cannot be 477 * converted to the type {@code short} by a 478 * widening conversion. 479 * @exception NullPointerException if the specified object is null 480 * and the field is an instance field. 481 * @exception ExceptionInInitializerError if the initialization provoked 482 * by this method fails. 483 * @see Field#get 484 */ 485 public short getShort(Object obj) 486 throws IllegalArgumentException, IllegalAccessException 487 { 488 return getFieldAccessor(obj).getShort(obj); 489 } 490 491 /** 492 * Gets the value of a static or instance field of type 493 * {@code int} or of another primitive type convertible to 494 * type {@code int} via a widening conversion. 495 * 496 * @param obj the object to extract the {@code int} value 497 * from 498 * @return the value of the field converted to type {@code int} 499 * 500 * @exception IllegalAccessException if the underlying field 501 * is inaccessible. 502 * @exception IllegalArgumentException if the specified object is not 503 * an instance of the class or interface declaring the 504 * underlying field (or a subclass or implementor 505 * thereof), or if the field value cannot be 506 * converted to the type {@code int} by a 507 * widening conversion. 508 * @exception NullPointerException if the specified object is null 509 * and the field is an instance field. 510 * @exception ExceptionInInitializerError if the initialization provoked 511 * by this method fails. 512 * @see Field#get 513 */ 514 public int getInt(Object obj) 515 throws IllegalArgumentException, IllegalAccessException 516 { 517 return getFieldAccessor(obj).getInt(obj); 518 } 519 520 /** 521 * Gets the value of a static or instance field of type 522 * {@code long} or of another primitive type convertible to 523 * type {@code long} via a widening conversion. 524 * 525 * @param obj the object to extract the {@code long} value 526 * from 527 * @return the value of the field converted to type {@code long} 528 * 529 * @exception IllegalAccessException if the underlying field 530 * is inaccessible. 531 * @exception IllegalArgumentException if the specified object is not 532 * an instance of the class or interface declaring the 533 * underlying field (or a subclass or implementor 534 * thereof), or if the field value cannot be 535 * converted to the type {@code long} by a 536 * widening conversion. 537 * @exception NullPointerException if the specified object is null 538 * and the field is an instance field. 539 * @exception ExceptionInInitializerError if the initialization provoked 540 * by this method fails. 541 * @see Field#get 542 */ 543 public long getLong(Object obj) 544 throws IllegalArgumentException, IllegalAccessException 545 { 546 return getFieldAccessor(obj).getLong(obj); 547 } 548 549 /** 550 * Gets the value of a static or instance field of type 551 * {@code float} or of another primitive type convertible to 552 * type {@code float} via a widening conversion. 553 * 554 * @param obj the object to extract the {@code float} value 555 * from 556 * @return the value of the field converted to type {@code float} 557 * 558 * @exception IllegalAccessException if the underlying field 559 * is inaccessible. 560 * @exception IllegalArgumentException if the specified object is not 561 * an instance of the class or interface declaring the 562 * underlying field (or a subclass or implementor 563 * thereof), or if the field value cannot be 564 * converted to the type {@code float} by a 565 * widening conversion. 566 * @exception NullPointerException if the specified object is null 567 * and the field is an instance field. 568 * @exception ExceptionInInitializerError if the initialization provoked 569 * by this method fails. 570 * @see Field#get 571 */ 572 public float getFloat(Object obj) 573 throws IllegalArgumentException, IllegalAccessException 574 { 575 return getFieldAccessor(obj).getFloat(obj); 576 } 577 578 /** 579 * Gets the value of a static or instance field of type 580 * {@code double} or of another primitive type convertible to 581 * type {@code double} via a widening conversion. 582 * 583 * @param obj the object to extract the {@code double} value 584 * from 585 * @return the value of the field converted to type {@code double} 586 * 587 * @exception IllegalAccessException if the underlying field 588 * is inaccessible. 589 * @exception IllegalArgumentException if the specified object is not 590 * an instance of the class or interface declaring the 591 * underlying field (or a subclass or implementor 592 * thereof), or if the field value cannot be 593 * converted to the type {@code double} by a 594 * widening conversion. 595 * @exception NullPointerException if the specified object is null 596 * and the field is an instance field. 597 * @exception ExceptionInInitializerError if the initialization provoked 598 * by this method fails. 599 * @see Field#get 600 */ 601 public double getDouble(Object obj) 602 throws IllegalArgumentException, IllegalAccessException 603 { 604 return getFieldAccessor(obj).getDouble(obj); 605 } 606 607 /** 608 * Sets the field represented by this {@code Field} object on the 609 * specified object argument to the specified new value. The new 610 * value is automatically unwrapped if the underlying field has a 611 * primitive type. 612 * 613 * <p>The operation proceeds as follows: 614 * 615 * <p>If the underlying field is static, the {@code obj} argument is 616 * ignored; it may be null. 617 * 618 * <p>Otherwise the underlying field is an instance field. If the 619 * specified object argument is null, the method throws a 620 * {@code NullPointerException}. If the specified object argument is not 621 * an instance of the class or interface declaring the underlying 622 * field, the method throws an {@code IllegalArgumentException}. 623 * 624 * <p>If this {@code Field} object enforces Java language access control, and 625 * the underlying field is inaccessible, the method throws an 626 * {@code IllegalAccessException}. 627 * 628 * <p>If the underlying field is final, the method throws an 629 * {@code IllegalAccessException} unless 630 * {@code setAccessible(true)} has succeeded for this field 631 * and this field is non-static. Setting a final field in this way 632 * is meaningful only during deserialization or reconstruction of 633 * instances of classes with blank final fields, before they are 634 * made available for access by other parts of a program. Use in 635 * any other context may have unpredictable effects, including cases 636 * in which other parts of a program continue to use the original 637 * value of this field. 638 * 639 * <p>If the underlying field is of a primitive type, an unwrapping 640 * conversion is attempted to convert the new value to a value of 641 * a primitive type. If this attempt fails, the method throws an 642 * {@code IllegalArgumentException}. 643 * 644 * <p>If, after possible unwrapping, the new value cannot be 645 * converted to the type of the underlying field by an identity or 646 * widening conversion, the method throws an 647 * {@code IllegalArgumentException}. 648 * 649 * <p>If the underlying field is static, the class that declared the 650 * field is initialized if it has not already been initialized. 651 * 652 * <p>The field is set to the possibly unwrapped and widened new value. 653 * 654 * <p>If the field is hidden in the type of {@code obj}, 655 * the field's value is set according to the preceding rules. 656 * 657 * @param obj the object whose field should be modified 658 * @param value the new value for the field of {@code obj} 659 * being modified 660 * 661 * @exception IllegalAccessException if the underlying field 662 * is inaccessible. 663 * @exception IllegalArgumentException if the specified object is not an 664 * instance of the class or interface declaring the underlying 665 * field (or a subclass or implementor thereof), 666 * or if an unwrapping conversion fails. 667 * @exception NullPointerException if the specified object is null 668 * and the field is an instance field. 669 * @exception ExceptionInInitializerError if the initialization provoked 670 * by this method fails. 671 */ 672 public void set(Object obj, Object value) 673 throws IllegalArgumentException, IllegalAccessException 674 { 675 getFieldAccessor(obj).set(obj, value); 676 } 677 678 /** 679 * Sets the value of a field as a {@code boolean} on the specified object. 680 * This method is equivalent to 681 * {@code set(obj, zObj)}, 682 * where {@code zObj} is a {@code Boolean} object and 683 * {@code zObj.booleanValue() == z}. 684 * 685 * @param obj the object whose field should be modified 686 * @param z the new value for the field of {@code obj} 687 * being modified 688 * 689 * @exception IllegalAccessException if the underlying field 690 * is inaccessible. 691 * @exception IllegalArgumentException if the specified object is not an 692 * instance of the class or interface declaring the underlying 693 * field (or a subclass or implementor thereof), 694 * or if an unwrapping conversion fails. 695 * @exception NullPointerException if the specified object is null 696 * and the field is an instance field. 697 * @exception ExceptionInInitializerError if the initialization provoked 698 * by this method fails. 699 * @see Field#set 700 */ 701 public void setBoolean(Object obj, boolean z) 702 throws IllegalArgumentException, IllegalAccessException 703 { 704 getFieldAccessor(obj).setBoolean(obj, z); 705 } 706 707 /** 708 * Sets the value of a field as a {@code byte} on the specified object. 709 * This method is equivalent to 710 * {@code set(obj, bObj)}, 711 * where {@code bObj} is a {@code Byte} object and 712 * {@code bObj.byteValue() == b}. 713 * 714 * @param obj the object whose field should be modified 715 * @param b the new value for the field of {@code obj} 716 * being modified 717 * 718 * @exception IllegalAccessException if the underlying field 719 * is inaccessible. 720 * @exception IllegalArgumentException if the specified object is not an 721 * instance of the class or interface declaring the underlying 722 * field (or a subclass or implementor thereof), 723 * or if an unwrapping conversion fails. 724 * @exception NullPointerException if the specified object is null 725 * and the field is an instance field. 726 * @exception ExceptionInInitializerError if the initialization provoked 727 * by this method fails. 728 * @see Field#set 729 */ 730 public void setByte(Object obj, byte b) 731 throws IllegalArgumentException, IllegalAccessException 732 { 733 getFieldAccessor(obj).setByte(obj, b); 734 } 735 736 /** 737 * Sets the value of a field as a {@code char} on the specified object. 738 * This method is equivalent to 739 * {@code set(obj, cObj)}, 740 * where {@code cObj} is a {@code Character} object and 741 * {@code cObj.charValue() == c}. 742 * 743 * @param obj the object whose field should be modified 744 * @param c the new value for the field of {@code obj} 745 * being modified 746 * 747 * @exception IllegalAccessException if the underlying field 748 * is inaccessible. 749 * @exception IllegalArgumentException if the specified object is not an 750 * instance of the class or interface declaring the underlying 751 * field (or a subclass or implementor thereof), 752 * or if an unwrapping conversion fails. 753 * @exception NullPointerException if the specified object is null 754 * and the field is an instance field. 755 * @exception ExceptionInInitializerError if the initialization provoked 756 * by this method fails. 757 * @see Field#set 758 */ 759 public void setChar(Object obj, char c) 760 throws IllegalArgumentException, IllegalAccessException 761 { 762 getFieldAccessor(obj).setChar(obj, c); 763 } 764 765 /** 766 * Sets the value of a field as a {@code short} on the specified object. 767 * This method is equivalent to 768 * {@code set(obj, sObj)}, 769 * where {@code sObj} is a {@code Short} object and 770 * {@code sObj.shortValue() == s}. 771 * 772 * @param obj the object whose field should be modified 773 * @param s the new value for the field of {@code obj} 774 * being modified 775 * 776 * @exception IllegalAccessException if the underlying field 777 * is inaccessible. 778 * @exception IllegalArgumentException if the specified object is not an 779 * instance of the class or interface declaring the underlying 780 * field (or a subclass or implementor thereof), 781 * or if an unwrapping conversion fails. 782 * @exception NullPointerException if the specified object is null 783 * and the field is an instance field. 784 * @exception ExceptionInInitializerError if the initialization provoked 785 * by this method fails. 786 * @see Field#set 787 */ 788 public void setShort(Object obj, short s) 789 throws IllegalArgumentException, IllegalAccessException 790 { 791 getFieldAccessor(obj).setShort(obj, s); 792 } 793 794 /** 795 * Sets the value of a field as an {@code int} on the specified object. 796 * This method is equivalent to 797 * {@code set(obj, iObj)}, 798 * where {@code iObj} is a {@code Integer} object and 799 * {@code iObj.intValue() == i}. 800 * 801 * @param obj the object whose field should be modified 802 * @param i the new value for the field of {@code obj} 803 * being modified 804 * 805 * @exception IllegalAccessException if the underlying field 806 * is inaccessible. 807 * @exception IllegalArgumentException if the specified object is not an 808 * instance of the class or interface declaring the underlying 809 * field (or a subclass or implementor thereof), 810 * or if an unwrapping conversion fails. 811 * @exception NullPointerException if the specified object is null 812 * and the field is an instance field. 813 * @exception ExceptionInInitializerError if the initialization provoked 814 * by this method fails. 815 * @see Field#set 816 */ 817 public void setInt(Object obj, int i) 818 throws IllegalArgumentException, IllegalAccessException 819 { 820 getFieldAccessor(obj).setInt(obj, i); 821 } 822 823 /** 824 * Sets the value of a field as a {@code long} on the specified object. 825 * This method is equivalent to 826 * {@code set(obj, lObj)}, 827 * where {@code lObj} is a {@code Long} object and 828 * {@code lObj.longValue() == l}. 829 * 830 * @param obj the object whose field should be modified 831 * @param l the new value for the field of {@code obj} 832 * being modified 833 * 834 * @exception IllegalAccessException if the underlying field 835 * is inaccessible. 836 * @exception IllegalArgumentException if the specified object is not an 837 * instance of the class or interface declaring the underlying 838 * field (or a subclass or implementor thereof), 839 * or if an unwrapping conversion fails. 840 * @exception NullPointerException if the specified object is null 841 * and the field is an instance field. 842 * @exception ExceptionInInitializerError if the initialization provoked 843 * by this method fails. 844 * @see Field#set 845 */ 846 public void setLong(Object obj, long l) 847 throws IllegalArgumentException, IllegalAccessException 848 { 849 getFieldAccessor(obj).setLong(obj, l); 850 } 851 852 /** 853 * Sets the value of a field as a {@code float} on the specified object. 854 * This method is equivalent to 855 * {@code set(obj, fObj)}, 856 * where {@code fObj} is a {@code Float} object and 857 * {@code fObj.floatValue() == f}. 858 * 859 * @param obj the object whose field should be modified 860 * @param f the new value for the field of {@code obj} 861 * being modified 862 * 863 * @exception IllegalAccessException if the underlying field 864 * is inaccessible. 865 * @exception IllegalArgumentException if the specified object is not an 866 * instance of the class or interface declaring the underlying 867 * field (or a subclass or implementor thereof), 868 * or if an unwrapping conversion fails. 869 * @exception NullPointerException if the specified object is null 870 * and the field is an instance field. 871 * @exception ExceptionInInitializerError if the initialization provoked 872 * by this method fails. 873 * @see Field#set 874 */ 875 public void setFloat(Object obj, float f) 876 throws IllegalArgumentException, IllegalAccessException 877 { 878 getFieldAccessor(obj).setFloat(obj, f); 879 } 880 881 /** 882 * Sets the value of a field as a {@code double} on the specified object. 883 * This method is equivalent to 884 * {@code set(obj, dObj)}, 885 * where {@code dObj} is a {@code Double} object and 886 * {@code dObj.doubleValue() == d}. 887 * 888 * @param obj the object whose field should be modified 889 * @param d the new value for the field of {@code obj} 890 * being modified 891 * 892 * @exception IllegalAccessException if the underlying field 893 * is inaccessible. 894 * @exception IllegalArgumentException if the specified object is not an 895 * instance of the class or interface declaring the underlying 896 * field (or a subclass or implementor thereof), 897 * or if an unwrapping conversion fails. 898 * @exception NullPointerException if the specified object is null 899 * and the field is an instance field. 900 * @exception ExceptionInInitializerError if the initialization provoked 901 * by this method fails. 902 * @see Field#set 903 */ 904 public void setDouble(Object obj, double d) 905 throws IllegalArgumentException, IllegalAccessException 906 { 907 getFieldAccessor(obj).setDouble(obj, d); 908 } 909 910 // Convenience routine which performs security checks 911 private FieldAccessor getFieldAccessor(Object obj) 912 throws IllegalAccessException 913 { 914 doSecurityCheck(obj); 915 boolean ov = override; 916 FieldAccessor a = (ov)? overrideFieldAccessor : fieldAccessor; 917 return (a != null)? a : acquireFieldAccessor(ov); 918 } 919 920 // NOTE that there is no synchronization used here. It is correct 921 // (though not efficient) to generate more than one FieldAccessor 922 // for a given Field. However, avoiding synchronization will 923 // probably make the implementation more scalable. 924 private FieldAccessor acquireFieldAccessor(boolean overrideFinalCheck) { 925 // First check to see if one has been created yet, and take it 926 // if so 927 FieldAccessor tmp = null; 928 if (root != null) tmp = root.getFieldAccessor(overrideFinalCheck); 929 if (tmp != null) { 930 if (overrideFinalCheck) 931 overrideFieldAccessor = tmp; 932 else 933 fieldAccessor = tmp; 934 } else { 935 // Otherwise fabricate one and propagate it up to the root 936 tmp = reflectionFactory.newFieldAccessor(this, overrideFinalCheck); 937 setFieldAccessor(tmp, overrideFinalCheck); 938 } 939 return tmp; 940 } 941 942 // Returns FieldAccessor for this Field object, not looking up 943 // the chain to the root 944 private FieldAccessor getFieldAccessor(boolean overrideFinalCheck) { 945 return (overrideFinalCheck)? overrideFieldAccessor : fieldAccessor; 946 } 947 948 // Sets the FieldAccessor for this Field object and 949 // (recursively) its root 950 private void setFieldAccessor(FieldAccessor accessor, boolean overrideFinalCheck) { 951 if (overrideFinalCheck) 952 overrideFieldAccessor = accessor; 953 else 954 fieldAccessor = accessor; 955 // Propagate up 956 if (root != null) { 957 root.setFieldAccessor(accessor, overrideFinalCheck); 958 } 959 } 960 961 // NOTE: be very careful if you change the stack depth of this 962 // routine. The depth of the "getCallerClass" call is hardwired so 963 // that the compiler can have an easier time if this gets inlined. 964 private void doSecurityCheck(Object obj) throws IllegalAccessException { 965 if (!override) { 966 if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) { 967 Class<?> caller = Reflection.getCallerClass(4); 968 Class<?> targetClass = ((obj == null || !Modifier.isProtected(modifiers)) 969 ? clazz 970 : obj.getClass()); 971 972 synchronized (this) { 973 if ((securityCheckCache == caller) 974 && (securityCheckTargetClassCache == targetClass)) { 975 return; 976 } 977 } 978 Reflection.ensureMemberAccess(caller, clazz, obj, modifiers); 979 synchronized (this) { 980 securityCheckCache = caller; 981 securityCheckTargetClassCache = targetClass; 982 } 983 } 984 } 985 } 986 987 /* 988 * Utility routine to paper over array type names 989 */ 990 static String getTypeName(Class<?> type) { 991 if (type.isArray()) { 992 try { 993 Class<?> cl = type; 994 int dimensions = 0; 995 while (cl.isArray()) { 996 dimensions++; 997 cl = cl.getComponentType(); 998 } 999 StringBuffer sb = new StringBuffer(); 1000 sb.append(cl.getName()); 1001 for (int i = 0; i < dimensions; i++) { 1002 sb.append("[]"); 1003 } 1004 return sb.toString(); 1005 } catch (Throwable e) { /*FALLTHRU*/ } 1006 } 1007 return type.getName(); 1008 } 1009 1010 /** 1011 * @throws NullPointerException {@inheritDoc} 1012 * @since 1.5 1013 */ 1014 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) { 1015 if (annotationClass == null) 1016 throw new NullPointerException(); 1017 1018 return (T) declaredAnnotations().get(annotationClass); 1019 } 1020 1021 /** 1022 * @since 1.5 1023 */ 1024 public Annotation[] getDeclaredAnnotations() { 1025 return AnnotationParser.toArray(declaredAnnotations()); 1026 } 1027 1028 private transient Map<Class<? extends Annotation>, Annotation> declaredAnnotations; 1029 1030 private synchronized Map<Class<? extends Annotation>, Annotation> declaredAnnotations() { 1031 if (declaredAnnotations == null) { 1032 declaredAnnotations = AnnotationParser.parseAnnotations( 1033 annotations, sun.misc.SharedSecrets.getJavaLangAccess(). 1034 getConstantPool(getDeclaringClass()), 1035 getDeclaringClass()); 1036 } 1037 return declaredAnnotations; 1038 } 1039 }