The Java™ Language
Specification
Java SE 7 Edition
James Gosling
Bill Joy
Guy Steele
Gilad Bracha
Alex Buckley
2012-02-06
Specification: JSR-000901 Java™ Language Specification ("Specification")
Version: 7
Status: Final Release
Release: July 2011
Copyright © 2011 Oracle America, Inc. and/or its affiliates. All rights reserved. 500 Oracle Parkway M/S 5op7, California 94065, U.S.A.
LIMITED LICENSE GRANTS
1.License for Evaluation Purposes. Oracle hereby grants you a fully-paid, non-exclusive, non-transferable, worldwide, limited license (without the right to sublicense), under Oracle's applicable intellectual property rights to view, download, use and reproduce the Specification only for the purpose of internal evaluation. This includes (i) developing applications intended to run on an implementation of the Specification, provided that such applications do not themselves implement any portion(s) of the Specification, and (ii) discussing the Specification with any third party; and (iii) excerpting brief portions of the Specification in oral or written communications which discuss the Specification provided that such excerpts do not in the aggregate constitute a significant portion of the Specification.
2.License for the Distribution of Compliant Implementations. Oracle also grants you a perpetual, non-exclusive, non-transferable, worldwide, fully paid-up, royalty free, limited license (without the right to sublicense) under any applicable copyrights or, subject to the provisions of subsection 4 below, patent rights it may have covering the Specification to create and/or distribute an Independent Implementation of the Specification that: (a) fully implements the Specification including all its required interfaces and functionality; (b) does not modify, subset, superset or otherwise extend the Licensor Name Space, or include any public or protected packages, classes, Java interfaces, fields or methods within the Licensor Name Space other than those required/authorized by the Specification or Specifications being implemented; and (c) passes the Technology Compatibility Kit (including satisfying the requirements of the applicable TCK Users Guide) for such Specification ("Compliant Implementation"). In addition, the foregoing license is expressly conditioned on your not acting outside its scope. No license is granted hereunder for any other purpose (including, for example, modifying the Specification, other than to the extent of your fair use rights, or distributing the Specification to third parties). Also, no right, title, or interest in or to any trademarks, service marks, or trade names of Oracle or Oracle's licensors is granted hereunder. Java, and Java-related logos, marks and names are trademarks or registered trademarks of Oracle in the U.S. and other countries.
3.Pass-through Conditions. You need not include limitations (a)-(c) from the previous paragraph or any other particular "pass through" requirements in any license You grant concerning the use of your Independent Implementation or products derived from it. However, except with respect to Independent Implementations (and products derived from them) that satisfy limitations (a)-(c) from the previous paragraph, You may neither: (a) grant or otherwise pass through to your licensees any licenses under Oracle's applicable intellectual property rights; nor (b) authorize your licensees to make any claims concerning their implementation's compliance with the Specification in question.
4. Reciprocity Concerning Patent Licenses.
a.With respect to any patent claims covered by the license granted under subparagraph 2 above that would be infringed by all technically feasible implementations of the Specification, such license is conditioned upon your offering on fair, reasonable and nondiscriminatory terms, to any party seeking it from You, a perpetual, non-exclusive, nontransferable, worldwide license under Your patent rights which are or would be infringed by all technically feasible implementations of the Specification to develop, distribute and use a Compliant Implementation.
b.With respect to any patent claims owned by Oracle and covered by the license granted under subparagraph 2, whether or not their infringement can be avoided in a technically feasible manner when implementing the Specification, such license shall terminate with respect to such claims if You initiate a claim against Oracle that it has, in the course of performing its responsibilities as the Specification Lead, induced any other entity to infringe Your patent rights.
c.Also with respect to any patent claims owned by Oracle and covered by the license granted under subparagraph 2 above, where the infringement of such claims can be avoided in a technically feasible manner when implementing the Specification such license, with respect to such claims, shall terminate if You initiate a claim against Oracle that its making, having made, using, offering to sell, selling or importing a Compliant Implementation infringes Your patent rights.
5. Definitions. For the purposes of this Agreement: "Independent Implementation" shall mean an implementation of the Specification that neither derives from any of Oracle's source code or binary code materials nor, except with an appropriate and separate license from Oracle, includes any of Oracle's source code or binary code materials; "Licensor Name Space" shall mean the public class or interface declarations whose names begin with "java", "javax", "com.sun" or their equivalents in any subsequent naming convention adopted by Oracle through the Java Community Process, or any recognized successors or replacements thereof; and "Technology Compatibility Kit" or "TCK" shall mean the test suite and accompanying TCK User's Guide provided by Oracle which corresponds to the Specification and that was available either (i) from Oracle 120 days before the first release of Your Independent Implementation that allows its use for commercial purposes, or (ii) more recently than 120 days from such release but against which You elect to test Your implementation of the Specification.
This Agreement will terminate immediately without notice from Oracle if you breach the Agreement or act outside the scope of the licenses granted above.
DISCLAIMER OF WARRANTIES
THE SPECIFICATION IS PROVIDED "AS IS". ORACLE MAKES NO REPRESENTATIONS OR WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO, WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT (INCLUDING AS A CONSEQUENCE OF ANY PRACTICE OR IMPLEMENTATION OF THE SPECIFICATION), OR THAT THE CONTENTS OF THE SPECIFICATION ARE SUITABLE FOR ANY PURPOSE. This document does not represent any commitment to release or implement any portion of the Specification in any product. In addition, the Specification could include technical inaccuracies or typographical errors.
LIMITATION OF LIABILITY
TO THE EXTENT NOT PROHIBITED BY LAW, IN NO EVENT WILL ORACLE OR ITS LICENSORS BE LIABLE FOR ANY DAMAGES, INCLUDING WITHOUT LIMITATION, LOST REVENUE, PROFITS OR DATA, OR FOR SPECIAL, INDIRECT, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF OR RELATED IN ANY WAY TO YOUR HAVING, IMPLEMENTING OR OTHERWISE USING THE SPECIFICATION, EVEN IF ORACLE AND/OR ITS LICENSORS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
You will indemnify, hold harmless, and defend Oracle and its licensors from any claims arising or resulting from: (i) your use of the Specification; (ii) the use or distribution of your Java application, applet and/or implementation; and/or (iii) any claims that later versions or releases of any Specification furnished to you are incompatible with the Specification provided to you under this license.
RESTRICTED RIGHTS LEGEND
U.S. Government: If this Specification is being acquired by or on behalf of the U.S. Government or by a U.S. Government prime contractor or subcontractor (at any tier), then the Government's rights in the Software and accompanying documentation shall be only as set forth in this license; this is in accordance with 48 C.F.R. 227.7201 through 227.7202-4 (for Department of Defense (DoD) acquisitions) and with 48 C.F.R. 2.101 and 12.212 (for non-DoD acquisitions).
REPORT
If you provide Oracle with any comments or suggestions concerning the Specification ("Feedback"), you hereby: (i) agree that such Feedback is provided on a non-proprietary and non-confidential basis, and (ii) grant Oracle a perpetual, non-exclusive, worldwide, fully paid-up, irrevocable license, with the right to sublicense through multiple levels of sublicensees, to incorporate, disclose, and use without limitation the Feedback for any purpose.
GENERAL TERMS
Any action related to this Agreement will be governed by California law and controlling U.S. federal law. The U.N. Convention for the International Sale of Goods and the choice of law rules of any jurisdiction will not apply.
The Specification is subject to U.S. export control laws and may be subject to export or import regulations in other countries. Licensee agrees to comply strictly with all such laws and regulations and acknowledges that it has the responsibility to obtain such licenses to export, re-export or import as may be required after delivery to Licensee.
This Agreement is the parties' entire agreement relating to its subject matter. It supersedes all prior or contemporaneous oral or written communications, proposals, conditions, representations and warranties and prevails over any conflicting or additional terms of any quote, order, acknowledgment, or other communication between the parties relating to its subject matter during the term of this Agreement. No modification to this Agreement will be binding, unless in writing and signed by an authorized representative of each party.
Table of Contents
Preface to the First Edition xv
Preface to the Second Edition xix
Preface to the Third Edition xxi
Preface to the Java SE 7 Edition xxv
1Introduction 1
1.1Organization of the Specification 2
1.2Example Programs 5
1.3Notation 6
1.4Relationship to Predefined Classes and Interfaces 6
1.5References 7
2Grammars 9
2.1Context-Free Grammars 9
2.2The Lexical Grammar 9
2.3The Syntactic Grammar 10
2.4Grammar Notation 10
3Lexical Structure 15
3.1Unicode 15
3.2Lexical Translations 16
3.3Unicode Escapes 17
3.4Line Terminators 18
3.5Input Elements and Tokens 19
3.6White Space 21
3.7Comments 21
3.8Identifiers 23
3.9Keywords 24
3.10Literals 25
3.10.1Integer Literals 25
3.10.2Floating-Point Literals 32
3.10.3Boolean Literals 35
3.10.4Character Literals 35
3.10.5String Literals 36
3.10.6Escape Sequences for Character and String Literals 39
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3.10.7 The Null Literal 39
3.11Separators 40
3.12Operators 40
4Types, Values, and Variables 41
4.1The Kinds of Types and Values 41
4.2Primitive Types and Values 42
4.2.1Integral Types and Values 43
4.2.2Integer Operations 43
4.2.3Floating-Point Types, Formats, and Values 45
4.2.4Floating-Point Operations 48
4.2.5The boolean Type and boolean Values 51
4.3Reference Types and Values 52
4.3.1Objects 54
4.3.2The Class Object 56
4.3.3The Class String 57
4.3.4When Reference Types Are the Same 57
4.4Type Variables 58
4.5Parameterized Types 60
4.5.1Type Arguments and Wildcards 61
4.5.2Members and Constructors of Parameterized Types 64
4.6Type Erasure 65
4.7Reifiable Types 66
4.8Raw Types 67
4.9Intersection Types 71
4.10Subtyping 72
4.10.1Subtyping among Primitive Types 72
4.10.2Subtyping among Class and Interface Types 73
4.10.3Subtyping among Array Types 73
4.11Where Types Are Used 74
4.12Variables 75
4.12.1Variables of Primitive Type 76
4.12.2Variables of Reference Type 76
4.12.3Kinds of Variables 78
4.12.4final Variables 80
4.12.5Initial Values of Variables 81
4.12.6Types, Classes, and Interfaces 82
5Conversions and Promotions 85
5.1Kinds of Conversion 88
5.1.1Identity Conversion 88
5.1.2Widening Primitive Conversion 88
5.1.3Narrowing Primitive Conversion 90
5.1.4Widening and Narrowing Primitive Conversion 93
5.1.5Widening Reference Conversion 93
5.1.6Narrowing Reference Conversion 93
5.1.7Boxing Conversion 94
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5.1.8Unboxing Conversion 95
5.1.9Unchecked Conversion 97
5.1.10Capture Conversion 97
5.1.11String Conversion 99
5.1.12Forbidden Conversions 100
5.1.13Value Set Conversion 100
5.2Assignment Conversion 101
5.3Method Invocation Conversion 106
5.4String Conversion 108
5.5Casting Conversion 108
5.5.1Reference Type Casting 111
5.5.2Checked Casts and Unchecked Casts 115
5.5.3Checked Casts at Run-time 116
5.6Numeric Promotions 117
5.6.1Unary Numeric Promotion 118
5.6.2Binary Numeric Promotion 119
6Names 121
6.1Declarations 122
6.2Names and Identifiers 127
6.3Scope of a Declaration 130
6.4Shadowing and Obscuring 133
6.4.1Shadowing 135
6.4.2Obscuring 138
6.5Determining the Meaning of a Name 140
6.5.1Syntactic Classification of a Name According to Context 141
6.5.2Reclassification of Contextually Ambiguous Names 143
6.5.3Meaning of Package Names 145
6.5.3.1Simple Package Names 145
6.5.3.2Qualified Package Names 146
6.5.4Meaning of PackageOrTypeNames 146
6.5.4.1Simple PackageOrTypeNames 146
6.5.4.2Qualified PackageOrTypeNames 146
6.5.5Meaning of Type Names 146
6.5.5.1Simple Type Names 146
6.5.5.2Qualified Type Names 146
6.5.6Meaning of Expression Names 147
6.5.6.1Simple Expression Names 147
6.5.6.2Qualified Expression Names 148
6.5.7Meaning of Method Names 151
6.5.7.1Simple Method Names 151
6.5.7.2Qualified Method Names 151
6.6Access Control 152
6.6.1Determining Accessibility 153
6.6.2Details on protected Access 157
6.6.2.1Access to a protected Member 157
6.6.2.2Qualified Access to a protected Constructor 158
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6.7Fully Qualified Names and Canonical Names 159
7Packages 163
7.1Package Members 163
7.2Host Support for Packages 165
7.3Compilation Units 167
7.4Package Declarations 168
7.4.1Named Packages 168
7.4.2Unnamed Packages 169
7.4.3Observability of a Package 170
7.5Import Declarations 170
7.5.1Single-Type-Import Declarations 171
7.5.2Type-Import-on-Demand Declarations 173
7.5.3Single-Static-Import Declarations 174
7.5.4Static-Import-on-Demand Declarations 175
7.6Top Level Type Declarations 175
8Classes 179
8.1Class Declarations 181
8.1.1Class Modifiers 181
8.1.1.1abstract Classes 182
8.1.1.2final Classes 184
8.1.1.3strictfp Classes 184
8.1.2Generic Classes and Type Parameters 185
8.1.3Inner Classes and Enclosing Instances 187
8.1.4Superclasses and Subclasses 190
8.1.5Superinterfaces 192
8.1.6Class Body and Member Declarations 195
8.2Class Members 196
8.3Field Declarations 201
8.3.1Field Modifiers 205
8.3.1.1static Fields 205
8.3.1.2final Fields 209
8.3.1.3transient Fields 209
8.3.1.4volatile Fields 209
8.3.2Initialization of Fields 211
8.3.2.1Initializers for Class Variables 211
8.3.2.2Initializers for Instance Variables 212
8.3.2.3Restrictions on the use of Fields during
Initialization 212
8.4Method Declarations 215
8.4.1Formal Parameters 216
8.4.2Method Signature 219
8.4.3Method Modifiers 220
8.4.3.1abstract Methods 221
8.4.3.2static Methods 222
8.4.3.3final Methods 223
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8.4.3.4native Methods 224
8.4.3.5strictfp Methods 224
8.4.3.6synchronized Methods 224
8.4.4Generic Methods 226
8.4.5Method Return Type 226
8.4.6Method Throws 227
8.4.7Method Body 228
8.4.8Inheritance, Overriding, and Hiding 229
8.4.8.1Overriding (by Instance Methods) 229
8.4.8.2Hiding (by Class Methods) 232
8.4.8.3Requirements in Overriding and Hiding 233
8.4.8.4Inheriting Methods with Override-Equivalent
Signatures 237
8.4.9Overloading 238
8.5Member Type Declarations 242
8.5.1Static Member Type Declarations 242
8.6Instance Initializers 243
8.7Static Initializers 243
8.8Constructor Declarations 244
8.8.1Formal Parameters and Type Parameters 245
8.8.2Constructor Signature 245
8.8.3Constructor Modifiers 245
8.8.4Generic Constructors 246
8.8.5Constructor Throws 247
8.8.6The Type of a Constructor 247
8.8.7Constructor Body 247
8.8.7.1 Explicit Constructor Invocations 248
8.8.8Constructor Overloading 251
8.8.9Default Constructor 251
8.8.10Preventing Instantiation of a Class 253
8.9Enums 253
8.9.1Enum Constants 254
8.9.2Enum Body Declarations 256
9Interfaces 263
9.1Interface Declarations 264
9.1.1Interface Modifiers 264
9.1.1.1abstract Interfaces 265
9.1.1.2strictfp Interfaces 265
9.1.2Generic Interfaces and Type Parameters 265
9.1.3Superinterfaces and Subinterfaces 266
9.1.4Interface Body and Member Declarations 267
9.2Interface Members 268
9.3Field (Constant) Declarations 269
9.3.1Initialization of Fields in Interfaces 271
9.4Abstract Method Declarations 271
9.4.1Inheritance and Overriding 272
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9.4.1.1Overriding (by Instance Methods) 273
9.4.1.2Requirements in Overriding 273
9.4.1.3Inheriting Methods with Override-Equivalent Signatures 273
9.4.2Overloading 274
9.5Member Type Declarations 274
9.6Annotation Types 275
9.6.1Annotation Type Elements 276
9.6.2Defaults for Annotation Type Elements 280
9.6.3Predefined Annotation Types 280
9.6.3.1@Target 280
9.6.3.2@Retention 281
9.6.3.3@Inherited 281
9.6.3.4@Override 282
9.6.3.5@SuppressWarnings 283
9.6.3.6@Deprecated 283
9.6.3.7@SafeVarargs 284
9.7Annotations 285
9.7.1Normal Annotations 286
9.7.2Marker Annotations 288
9.7.3Single-Element Annotations 289
10Arrays 291
10.1Array Types 292
10.2Array Variables 292
10.3Array Creation 294
10.4Array Access 294
10.5Array Store Exception 295
10.6Array Initializers 297
10.7Array Members 298
10.8Class Objects for Arrays 300
10.9An Array of Characters is Not a String 301
11Exceptions 303
11.1The Kinds and Causes of Exceptions 304
11.1.1The Kinds of Exceptions 304
11.1.2The Causes of Exceptions 305
11.1.3Asynchronous Exceptions 305
11.2Compile-Time Checking of Exceptions 306
11.2.1Exception Analysis of Expressions 308
11.2.2Exception Analysis of Statements 308
11.2.3Exception Checking 309
11.3Run-Time Handling of an Exception 311
12Execution 315
12.1Java virtual machine Start-Up 315
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12.1.1Load the Class Test 316
12.1.2Link Test: Verify, Prepare, (Optionally) Resolve 316
12.1.3Initialize Test: Execute Initializers 317
12.1.4Invoke Test.main 318
12.2Loading of Classes and Interfaces 318
12.2.1The Loading Process 319
12.3Linking of Classes and Interfaces 320
12.3.1Verification of the Binary Representation 320
12.3.2Preparation of a Class or Interface Type 321
12.3.3Resolution of Symbolic References 321
12.4Initialization of Classes and Interfaces 322
12.4.1When Initialization Occurs 323
12.4.2Detailed Initialization Procedure 325
12.5Creation of New Class Instances 327
12.6Finalization of Class Instances 331
12.6.1Implementing Finalization 332
12.6.2Interaction with the Memory Model 334
12.7Unloading of Classes and Interfaces 335
12.8Program Exit 336
13Binary Compatibility 337
13.1The Form of a Binary 338
13.2What Binary Compatibility Is and Is Not 343
13.3Evolution of Packages 344
13.4Evolution of Classes 344
13.4.1abstract Classes 344
13.4.2final Classes 344
13.4.3public Classes 345
13.4.4Superclasses and Superinterfaces 345
13.4.5Class Type Parameters 346
13.4.6Class Body and Member Declarations 347
13.4.7Access to Members and Constructors 348
13.4.8Field Declarations 350
13.4.9final Fields and Constants 352
13.4.10static Fields 354
13.4.11transient Fields 354
13.4.12Method and Constructor Declarations 354
13.4.13Method and Constructor Type Parameters 355
13.4.14Method and Constructor Formal Parameters 356
13.4.15Method Result Type 357
13.4.16abstract Methods 357
13.4.17final Methods 358
13.4.18native Methods 358
13.4.19static Methods 359
13.4.20synchronized Methods 359
13.4.21Method and Constructor Throws 359
13.4.22Method and Constructor Body 359
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13.4.23Method and Constructor Overloading 359
13.4.24Method Overriding 361
13.4.25Static Initializers 361
13.4.26Evolution of Enums 361
13.5Evolution of Interfaces 361
13.5.1public Interfaces 361
13.5.2Superinterfaces 362
13.5.3Interface Members 362
13.5.4Interface Type Parameters 362
13.5.5Field Declarations 363
13.5.6abstract Methods 363
13.5.7Evolution of Annotation Types 363
14Blocks and Statements 365
14.1Normal and Abrupt Completion of Statements 365
14.2Blocks 367
14.3Local Class Declarations 367
14.4Local Variable Declaration Statements 369
14.4.1Local Variable Declarators and Types 370
14.4.2Execution of Local Variable Declarations 370
14.5Statements 371
14.6The Empty Statement 373
14.7Labeled Statements 373
14.8Expression Statements 374
14.9The if Statement 375
14.9.1The if-then Statement 375
14.9.2The if-then-else Statement 376
14.10The assert Statement 376
14.11The switch Statement 379
14.12The while Statement 383
14.12.1Abrupt Completion of while Statement 384
14.13The do Statement 385
14.13.1Abrupt Completion of do Statement 385
14.14The for Statement 387
14.14.1The basic for Statement 387
14.14.1.1Initialization of for Statement 388
14.14.1.2Iteration of for Statement 388
14.14.1.3Abrupt Completion of for Statement 389
14.14.2The enhanced for statement 390
14.15The break Statement 392
14.16The continue Statement 394
14.17The return Statement 396
14.18The throw Statement 397
14.19The synchronized Statement 399
14.20The try statement 401
14.20.1Execution of try-catch 404
14.20.2Execution of try-finally and try-catch-finally 405
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14.20.3try-with-resources 407
14.20.3.1Basic try-with-resources 408
14.20.3.2Extended try-with-resources 411
14.21Unreachable Statements 411
15Expressions 417
15.1Evaluation, Denotation, and Result 417
15.2Variables as Values 418
15.3Type of an Expression 418
15.4FP-strict Expressions 419
15.5Expressions and Run-time Checks 419
15.6Normal and Abrupt Completion of Evaluation 421
15.7Evaluation Order 423
15.7.1Evaluate Left-Hand Operand First 423
15.7.2Evaluate Operands before Operation 425
15.7.3Evaluation Respects Parentheses and Precedence 425
15.7.4Argument Lists are Evaluated Left-to-Right 427
15.7.5Evaluation Order for Other Expressions 428
15.8Primary Expressions 428
15.8.1Lexical Literals 429
15.8.2Class Literals 430
15.8.3this 430
15.8.4Qualified this 431
15.8.5Parenthesized Expressions 432
15.9Class Instance Creation Expressions 432
15.9.1Determining the Class being Instantiated 434
15.9.2Determining Enclosing Instances 435
15.9.3Choosing the Constructor and its Arguments 437
15.9.4Run-time Evaluation of Class Instance Creation Expressions 439
15.9.5Anonymous Class Declarations 440
15.9.5.1Anonymous Constructors 441
15.10Array Creation Expressions 442
15.10.1Run-time Evaluation of Array Creation Expressions 443
15.11Field Access Expressions 446
15.11.1Field Access Using a Primary 447
15.11.2Accessing Superclass Members using super 450
15.12Method Invocation Expressions 451
15.12.1Compile-Time Step 1: Determine Class or Interface to Search 452
15.12.2Compile-Time Step 2: Determine Method Signature 453
15.12.2.1Identify Potentially Applicable Methods 459
15.12.2.2Phase 1: Identify Matching Arity Methods Applicable by Subtyping 460
15.12.2.3Phase 2: Identify Matching Arity Methods Applicable by Method Invocation Conversion 461
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15.12.2.4Phase 3: Identify Applicable Variable Arity Methods 462
15.12.2.5Choosing the Most Specific Method 462
15.12.2.6Method Result and Throws Types 465
15.12.2.7Inferring Type Arguments Based on Actual Arguments 466
15.12.2.8Inferring Unresolved Type Arguments 477
15.12.3Compile-Time Step 3: Is the Chosen Method Appropriate? 478
15.12.4Run-time Evaluation of Method Invocation 481
15.12.4.1Compute Target Reference (If Necessary) 481
15.12.4.2Evaluate Arguments 483
15.12.4.3Check Accessibility of Type and Method 484
15.12.4.4Locate Method to Invoke 485
15.12.4.5Create Frame, Synchronize, Transfer Control 488
15.13Array Access Expressions 490
15.13.1Run-time Evaluation of Array Access 491
15.14Postfix Expressions 493
15.14.1Expression Names 493
15.14.2Postfix Increment Operator ++ 494
15.14.3Postfix Decrement Operator -- 494
15.15Unary Operators 495
15.15.1Prefix Increment Operator ++ 496
15.15.2Prefix Decrement Operator -- 497
15.15.3Unary Plus Operator + 497
15.15.4Unary Minus Operator - 498
15.15.5Bitwise Complement Operator ~ 498
15.15.6Logical Complement Operator ! 499
15.16Cast Expressions 499
15.17Multiplicative Operators 500
15.17.1Multiplication Operator * 501
15.17.2Division Operator / 502
15.17.3Remainder Operator % 503
15.18Additive Operators 506
15.18.1String Concatenation Operator + 506
15.18.2Additive Operators (+ and -) for Numeric Types 509
15.19Shift Operators 511
15.20Relational Operators 512
15.20.1Numerical Comparison Operators <, <=, >, and >= 512
15.20.2Type Comparison Operator instanceof 513
15.21Equality Operators 514
15.21.1Numerical Equality Operators == and != 515
15.21.2Boolean Equality Operators == and != 516
15.21.3Reference Equality Operators == and != 517
15.22Bitwise and Logical Operators 517
15.22.1Integer Bitwise Operators &, ^, and | 518
15.22.2Boolean Logical Operators &, ^, and | 519
15.23Conditional-And Operator && 519
15.24Conditional-Or Operator || 520
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15.25Conditional Operator ? : 521
15.26Assignment Operators 523
15.26.1Simple Assignment Operator = 524
15.26.2Compound Assignment Operators 529
15.27Expression 535
15.28Constant Expressions 536
16Definite Assignment 539
16.1Definite Assignment and Expressions 545
16.1.1Boolean Constant Expressions 545
16.1.2Conditional-And Operator && 545
16.1.3Conditional-Or Operator || 546
16.1.4Logical Complement Operator ! 546
16.1.5Conditional Operator ? : 546
16.1.6Conditional Operator ? : 547
16.1.7Other Expressions of Type boolean 547
16.1.8Assignment Expressions 547
16.1.9Operators ++ and -- 548
16.1.10Other Expressions 548
16.2Definite Assignment and Statements 549
16.2.1Empty Statements 549
16.2.2Blocks 549
16.2.3Local Class Declaration Statements 551
16.2.4Local Variable Declaration Statements 551
16.2.5Labeled Statements 551
16.2.6Expression Statements 552
16.2.7if Statements 552
16.2.8assert Statements 552
16.2.9switch Statements 553
16.2.10while Statements 553
16.2.11do Statements 554
16.2.12for Statements 554
16.2.12.1Initialization Part of for Statement 555
16.2.12.2Incrementation Part of for Statement 555
16.2.13break, continue, return, and throw Statements 556
16.2.14synchronized Statements 556
16.2.15try Statements 556
16.3Definite Assignment and Parameters 558
16.4Definite Assignment and Array Initializers 558
16.5Definite Assignment and Enum Constants 559
16.6Definite Assignment and Anonymous Classes 559
16.7Definite Assignment and Member Types 559
16.8Definite Assignment and Static Initializers 560
16.9Definite Assignment, Constructors, and Instance Initializers 560
17Threads and Locks 563
17.1Synchronization 564
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17.2Wait Sets and Notification 564
17.2.1Wait 565
17.2.2Notification 566
17.2.3Interruptions 567
17.2.4Interactions of Waits, Notification, and Interruption 567
17.3Sleep and Yield 568
17.4Memory Model 569
17.4.1Shared Variables 572
17.4.2Actions 572
17.4.3Programs and Program Order 573
17.4.4Synchronization Order 574
17.4.5Happens-before Order 575
17.4.6Executions 578
17.4.7Well-Formed Executions 579
17.4.8Executions and Causality Requirements 579
17.4.9Observable Behavior and Nonterminating Executions 582
17.5final Field Semantics 584
17.5.1Semantics of final Fields 586
17.5.2Reading final Fields During Construction 586
17.5.3Subsequent Modification of final Fields 587
17.5.4Write-protected Fields 588
17.6Word Tearing 589
17.7Non-atomic Treatment of double and long 590
18Syntax 591 Index 607
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