Java Language Specification, Java SE 8 Edition, The

James Gosling is the creator of the Java programming language and a former Fellow at Sun Microsystems. He developed the original Java compiler and Java Virtual Machine, and was a principal in the Andrew project at Carnegie Mellon University, where he earned a Ph.D. in Computer Science. He joined Liquid Robotics as Chief Software Architect in 2011.   Bill Joy is a co-founder of Sun Microsystems and was the principal architect of the Berkeley version of UNIX®, for which he received a lifetime achievement award from the USENIX Association in 1993. Joy has had a central role in shaping the Java programming language. He joined KPCB as a Greentech Partner in 2005.   Guy L. Steele Jr. is a Software Architect at Oracle Labs, where he conducts research in language design and implementation strategies, parallel algorithms, and computer arithmetic. Steele is a co-creator of the Scheme programming language, an ACM Fellow, an IEEE Fellow, and a member of the National Academy of Engineering.   Gilad Bracha is the creator of the Newspeak programming language and a former Distinguished Engineer at Sun Microsystems. Prior to Sun, he worked on Strongtalk, the Animorphic Smalltalk System. He holds a Ph.D. in Computer Science from the University of Utah.   Alex Buckley is the Specification Lead for the Java programming language and the Java Virtual Machine at Oracle. He holds a Ph.D. in Computing from Imperial College London.

Preface to the Java SE 8 Edition         xxi

 

Chapter 1: Introduction         1

1.1 Organization of the Specification   2

1.2 Example Programs   6

1.3 Notation   6

1.4 Relationship to Predefined Classes and Interfaces   7

1.5 Feedback   7

1.6 References   7

 

Chapter 2: Grammars         9

2.1 Context-Free Grammars   9

2.2 The Lexical Grammar   9

2.3 The Syntactic Grammar   10

2.4 Grammar Notation   10

 

Chapter 3: Lexical Structure         15

3.1   Unicode   15

3.2   Lexical Translations   16

3.3   Unicode Escapes   17

3.4   Line Terminators   19

3.5   Input Elements and Tokens   19

3.6   White Space   20

3.7   Comments   21

3.8   Identifiers   22

3.9   Keywords   24

3.10 Literals   24

3.11 Separators   38

3.12 Operators   38

 

Chapter 4: Types, Values, and Variables         41

4.1   The Kinds of Types and Values   41

4.2   Primitive Types and Values   42

4.3   Reference Types and Values   52

4.4   Type Variables   57

4.5   Parameterized Types   59

4.6   Type Erasure   64

4.7   Reifiable Types   64

4.8   Raw Types   66

4.9   Intersection Types   70

4.10 Subtyping   71

4.11 Where Types Are Used   75

4.12 Variables   80

 

Chapter 5: Conversions and Contexts         91

5.1 Kinds of Conversion   94

5.2 Assignment Contexts   107

5.3 Invocation Contexts   112

5.4 String Contexts   114

5.5 Casting Contexts   114

5.6 Numeric Contexts   124

 

Chapter 6: Names         129

6.1 Declarations   130

6.2 Names and Identifiers   137

6.3 Scope of a Declaration   139

6.4 Shadowing and Obscuring   142

6.5 Determining the Meaning of a Name   148

6.6 Access Control   161

6.7 Fully Qualified Names and Canonical Names   169

 

Chapter 7: Packages         173

7.1 Package Members   173

7.3 Compilation Units   177

7.4 Package Declarations   178

7.5 Import Declarations   180

7.6 Top Level Type Declarations   185

 

Chapter 8: Classes         189

8.1 Class Declarations   191

8.2 Class Members   206

8.3 Field Declarations   211

8.4 Method Declarations   225

8.5 Member Type Declarations   254

8.6 Instance Initializers   255

8.7 Static Initializers   255

8.8 Constructor Declarations   256

8.9 Enum Types   266

 

Chapter 9: Interfaces         277

9.1 Interface Declarations   278

9.2 Interface Members   282

9.3 Field (Constant) Declarations   283

9.4 Method Declarations   286

9.5 Member Type Declarations   291

9.6 Annotation Types   292

9.7 Annotations   308

9.8 Functional Interfaces   319

9.9 Function Types   323

 

Chapter 10: Arrays         329

10.1 Array Types   330

10.2 Array Variables   330

10.3 Array Creation   332

10.4 Array Access   332

10.5 Array Store Exception   333

10.6 Array Initializers   335

10.7 Array Members   336

10.8 Class Objects for Arrays   338

10.9 An Array of Characters Is Not a String   339

 

Chapter 11: Exceptions         341

11.1 The Kinds and Causes of Exceptions   342

11.2 Compile-Time Checking of Exceptions   344

11.3 Run-Time Handling of an Exception   349

 

Chapter 12: Execution         353

12.1 Java Virtual Machine Startup   353

12.2 Loading of Classes and Interfaces   356

12.3 Linking of Classes and Interfaces   358

12.4 Initialization of Classes and Interfaces   360

12.5 Creation of New Class Instances   365

12.6 Finalization of Class Instances   369

12.7 Unloading of Classes and Interfaces   373

12.8 Program Exit   374

 

Chapter 13: Binary Compatibility         375

13.1 The Form of a Binary   376

13.2 What Binary Compatibility Is and Is Not   382

13.3 Evolution of Packages   383

13.4 Evolution of Classes   383

13.5 Evolution of Interfaces   400

 

Chapter 14: Blocks and Statements          405

14.1   Normal and Abrupt Completion of Statements   405

14.2   Blocks   407

14.3   Local Class Declarations   407

14.4   Local Variable Declaration Statements   408

14.5   Statements   410

14.6   The Empty Statement   412

14.7   Labeled Statements   413

14.8   Expression Statements   414

14.9   The if  Statement   415

14.10 The assert  Statement   416

14.11 The switch  Statement   419

14.12 The while  Statement   423

14.13 The do  Statement   424

14.14 The for  Statement   426

14.15 The break  Statement   432

14.16 The continue  Statement   434

14.17 The return  Statement   436

14.18 The throw  Statement   437

14.19 The synchronized  Statement   439

14.20 The try  statement   440

14.21 Unreachable Statements   452

 

Chapter 15: Expressions         459

15.1   Evaluation, Denotation, and Result   459

15.2   Forms of Expressions   460

15.3   Type of an Expression   461

15.4   FP-strict Expressions   462

15.5   Expressions and Run-Time Checks   462

15.6   Normal and Abrupt Completion of Evaluation   464

15.7   Evaluation Order   466

15.8   Primary Expressions   471

15.9   Class Instance Creation Expressions   476

15.10 Array Creation and Access Expressions   487

15.11 Field Access Expressions   494

15.12 Method Invocation Expressions   499

15.13 Method Reference Expressions   529

15.14 Postfix Expressions   542

15.15 Unary Operators   544

15.16 Cast Expressions   549

15.17 Multiplicative Operators   550

15.18 Additive Operators   556

15.19 Shift Operators   561

15.20 Relational Operators   562

15.21 Equality Operators   565

15.22 Bitwise and Logical Operators   568

15.23 Conditional-And Operator &&   570

15.24 Conditional-Or Operator ||   570

15.25 Conditional Operator ? :   571

15.26 Assignment Operators   581

15.27 Lambda Expressions   594

15.28 Constant Expressions   605

 

Chapter 16: Definite Assignment         607

16.1 Definite Assignment and Expressions   613

16.2 Definite Assignment and Statements   617

16.3 Definite Assignment and Parameters   626

16.4 Definite Assignment and Array Initializers   626

16.5 Definite Assignment and Enum Constants   626

16.6 Definite Assignment and Anonymous Classes   627

16.7 Definite Assignment and Member Types   627

16.8 Definite Assignment and Static Initializers   628

16.9 Definite Assignment, Constructors, and Instance Initializers   628

 

Chapter 17: Threads and Locks         631

17.1 Synchronization   632

17.2 Wait Sets and Notification   632

17.3 Sleep and Yield   636

17.4 Memory Model   637

17.5 final Field Semantics   652

17.6 Word Tearing   657

17.7 Non-Atomic Treatment of double  and long   658

 

Chapter 18: Type Inference         659

18.1 Concepts and Notation   660

18.2 Reduction   663

18.3 Incorporation   673

18.4 Resolution   675

18.5 Uses of Inference   677

 

Chapter 19: Syntax         689

 

Index         715

 

Appendix A: Limited License Grant         755