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The Java Language Specification 3rd
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A
- abrupt completion
- See completion, abrupt
abstractmodifier- See also declarations; modifiers
- classes
- methods
- and
supermethod invocation, 355
- access
- See also scope
- accessibility
- array, 211
- constructor, binary compatibility considerations, 261
- of fields, expression evaluation, 341
- inheritance of class members, example
- default, 149
private, 151protected, 150public, 150
- interface member names, 202
- access (continued)
- method, binary compatibility considerations, 267
- non-
publicclass instances, throughpublicsuperclasses and superinterfaces, 151 - overridden methods, using
superkeyword, 178 - qualified
- See also field access expressions; method invocation expressions
- term definition, 104
- access control
- See also security
- classes, example, 107
- constructors
- default, example, 108
private, example, 111protected, example, 110public, example, 109
- fields
- default, example, 108
private, example, 111protected, example, 110public, example, 109
- methods
- default, example, 108
private, example, 111protected, example, 110public, example, 109
- package names, limited significance of, 120
protected, details of, 105- and qualified names, 104
- term definition, 104
- accessible
- accessible (continued)
- actions
- algebraic identities
- See also expressions; mathematical functions
- limits on use of, 325
- alphabet
- See also syntax
- components
- See characters
- data types
- See primitive types
- term definition, 9
- ambiguity
- anonymous class, 135
- anonymous class (continued)
- argument
- arithmetic
- See also floating point; integers; numbers; operators; primitive types
- integer division,
ArithmeticException, 321 - operators, numeric promotion, specification, 77
- arrays
- See also classes; data structures
- (chapter), 209
- access, 211
- assignment, expression evaluation order, 394
- character, distinguished from strings, 215
ClassCloneableinterface implemented by, 214- components
- creation, 42, 211
- example, 210
- arrays (continued)
- exceptions,
ArrayStoreException, 217 - indexing of, 211
- initialization, 211, 212
- members, 92, 213
- names, fully qualified, 111
Objectas superclass of, 215- origin, 211
- variables
- exceptions,
- ASCII characters
- See also characters; Unicode character set
- Unicode character set relationship to, 14
- assignment
- See also fields; initialization
- array, expression evaluation order, 394, 399
- assignable to, term definition, 66
- compatible, term definition, 66
- compound
- conversion context, specification, 56, 66
- definite, (chapter), 407
- expressions
- operation, to change value of primitive value, 33
- simple operators, evaluation, 393
- backslash (
\) - backspace
- base
- Beta, 3, 7
- biblical quotations
- bibliographic references
- binary
- compatibility
- See also code generation; compile-time errors; exceptions
- (chapter), 251
- changes that do not break, 252
- compatible with, term definition, 256
- contrasted with source compatibility, 257
- file format, required properties, 253
- name
- numeric promotion, specification, 79
- representation, verification of classesand interfaces, 232
- compatibility
- blank final
- field
- variable
- blocks
- blocks (continued)
- Bobrow, Daniel G., 6
- body
- boolean
- bootstrap loader
- See class loaders, bootstrap
- brackets (
[]) breakstatement- Burke, Edmund, 275
- Burroughs, Edgar Rice, 301
- Burton, Robert, xxiii
- but not phrase
bytetype- See also integral types; numbers; primitive types
- value range, 33
- C, 1, 2, 7
- C++, 1, 2, 6
- Caesar, Julius, 374
- caller
- carriage return (
CR) - casting
catchclause, 303- See also control flow;
trystatement - exception handling role of, 219
- exception idiom defined with, 226
- scope of parameters, 86, 306
- See also control flow;
- Cervantes, Migel de, 72
- characters
- See also numbers; primitive types; strings
- array of, distinguished from strings, 215
chartype, 31- See also integral types; numbers; primitive types
- value range, 33
- line terminators, 27
- literals
- Unicode character set
- Chase, Lincoln, 118
- checking
- See also exceptions, checked; throw
- for exception handlers, at compile-time, 221
- Christie, Agatha, 276, 288, 347
- circular declaration
- circular declaration (continued)
- class literal, 95
- class loaders
- class(es)
- See also fields; inheritance; interfaces; methods; packages; subclasses; superclasses; superinterfaces
- (chapter), 135
abstract, 137- accessibility, 105
- anonymous
- See anonymous class
- binary compatibility considerations, 257
- binary representation
- body
.classsuffix, as name for compiled files, 122Classobjects, associated with arrays, 215- constructors, binary compatibility considerations, 267
- declarations, 136
- as declared entity, 81
- exceptions
ClassCastException, 75
- class(es) (continued)
- exceptions (continued)
final- finalization of, 258
- FP-strict, 319
- inaccessible, accessing members of, 151 example, 151
- initialization, 236
- instances
- See instance(s)
- instantiation, preventing, 190
- linking
- loading, 232
- local
- See local class
- member
- See member class
- members, 90
- methods
- class, 171
- interface, 205
- non-
static, 172 static, 171
- named, 135
- class(es) (continued)
- names, fully qualified, 111
- naming conventions, 114
- nested
- See nested classes
- non-
public, in example of qualified names and access control, 107 - preparation, 234
- preventing instantiation of, 139
public- references to, binary file format requirements, 253
- resolution
- scope of, 85, 125
- in scope of an imported type, 85, 125
- static initializers, 189
- that depend on themselves
- See circular declaration, of a class
- that directly depend on a reference type
- See circular declaration, of a class
- top-level
- type declarations, as members of packages, 129
- unloading of, 248
- variables
- verification, at virtual machine startup, 230
- classification
- classification (continued)
- code generation
- See also binary, compatibility; compile-time errors; exceptions; optimization
- asynchronous exceptions, implications for, 224
- initialization, implications for, 241
- symbolic reference resolution, implications of, 235
- comments
- Common Lisp, 6
- compatibility
- See binary, compatibility
- compilation
- See also compile-time errors; exceptions; virtual machine
- CompilationUnit goal symbol, syntactic grammar use, 10
- conditional
- exception handlers checked for during, 221
- unit
- components, package declarations, 124
- and default accessibility of top-level types, 129
- implicitly starts with
import java.lang.*, 128 - importing types into, 125
- and meaning of a simple type name, 99
- and name of top-level type, 129
- overview, 119
- and package membership, 89, 119
- and package observability, 125
- and scope of an import declaration, 85, 125
- term definition and characteristics, 123
- compile-time constant
- See constants
- compile-time errors
- See binary, compatibility; errors; exceptions
- completion, 276
- See also control flow, exceptions
- abrupt
breakstatement, 297continuestatement, 299- disallowed for static initializers, 189
- during expression evaluation, 320
forstatement, 295- labeled statements, 286
- reasons for, 276, 321
returnstatement, 301synchronizedstatement, 304throwstatement, 302trystatement, 305try-catchstatement, 307try-catch-finallystatement, 308
- normal
- component(s)
- See also arrays, components
- type, arrays, 210
- conflicts
- name
- See also hiding; obscuring; scope; shadowing
- avoiding through use of syntactic context, 94
- name
- Conner, Michael, 251
- constants
- See also fields; class;
final; fields, interface; literals - are always FP-strict, 319
- characteristics and binary compatibility considerations, 264
- compile-time narrowing of
- expressions, 405
- field, term specification, 264
- may be declared in inner class, 140
- named
- See fields; class;
final
- See fields; class;
- See also fields; class;
- constructors
- See also class(es); execution; initialization; interfaces; methods
- access, 105
- binary compatibility considerations, 261
- control
- default, example, 108
private, example, 111protected, example, 110public, example, 109
- hidden fields,
thiskeyword use for, 283
- accessibility, 105
- allow field access through super, 344
- anonymous
- anonymous class
- are not members, 148
- body, 192
- as components of a class body, 147
- declarations, 190
- default, 195
- definite assignment and unassignment within, 427
- definite assignment of variables before, 418
- deleting, binary compatibility considerations, 267
- determining arguments to, 334
- each must declare exceptions from instance initializers, 188
- explicit invocation statements, 193
- explicit invocations, 105
- FP-strict, 319
- invocation, during instance creation, 242
- modifiers, 191
- must assign all blank final instance variables, 156
- must assign blank final fields, 156
- names of, 83, 190
- as non-members of a class, 90
- overloading, 195
- parameters, 191
- See also arguments
- constructors (continued)
- parameters (continued)
private, preventing instantiation with, 139, 197protected, accessibility of, 105, 106- signature, 191
throwsclause, binary compatibility considerations, 270- and unreachable statements, 310
- when reachable, 311
- context(s)
- See also inheritance; scope
- conversion, 56
- reclassification of contextually ambiguous names, 96
- role in determining the meaning of a name, 81, 93
- static
- See static context
- syntactic classification of a name according to, 94
- context-free grammars
- See grammars, context-free
continuestatement- contract
- See also binary, compatibility
- term definition, 256
- control flow
- See also completion; definite assignment; exceptions; expressions; statements; statements, unreachable; threads
booleanexpressions use for, 40
- control flow (continued)
breakstatement, specification, 297continuestatement, specification, 299- deadlock avoidance, multiple lock use for, 305
dostatement, specification, 293forstatement, specification, 295ifstatement, danglingelsehandling, 284if-thenstatement, specification, 288if-then-elsestatement, specification, 288- local variable declaration and
switchstatement, 49 returnstatement, specification, 301switchstatement, specification, 288synchronizedstatement, specification, 304throwstatement, specification, 302trystatement, specification, 305try-catchstatement, specification, 307try-catch-finallystatement, specification, 308whilestatement, specification, 292
- conventions
- conversion
- See also casting; numbers; promotion
- (chapter), 55
- casting, 72
- contexts
- forbidden, specification, 64
- identity
- kinds of, 58
- in method invocations, 71
- narrowing
- conversion (continued)
- narrowing (continued)
- reference
- string, 72
- term definition, 55
- value set
- widening
- primitive
- reference, 62
- term specification, 62
- creation
- See also declaration; initialization
- array, 42, 211
- expression evaluation
- instance, 42
- creation (continued)
- Creatore, Luigi, 30
- Danforth, Scott, 251
- dangling
else- See also control flow
- handling of, 284
- data
- database
- deadlock
- decimal
- declarations
- See also body; execution; methods; parameters; statements
- class
- constructor, 190
- field(s), 153
- declarations (continued)
- identifiers in, kept separate from those in labeled statements, 84
import- instance variable, 48
- interface, 200
- local variable, definite assignment, 419
- method(s), 167
- examples of, 180
- interface,
abstract, 205
- modifiers
- overriding, example, 180
- package, in compilation units, 123
- scope of, 85
- shadowed, term definition, 86
- shadowing, 86
- subclass, 142
- superclass, 142
- superinterface, 144, 201
- term definition, 82
- type
- variable
- declarator
- definite assignment
- See also exceptions; execution; scope
- definite assignment (continued)
- (chapter), 407
- and anonymous classes, 426
- of blank final class variables, 156
- of instance variables, 156
- and local classes, 418
- of member types, 426
- and parameters, 425
- and qualified class instance creation, 417
- requirement for locals and parameters before an inner class, 141
- and static initializers, 426
- of variables with respect to nested classes, 418
- definite unassignment, 407
- DeMichiel, Linda G., 6
- denormalized
- digits
- directly depends
- division
dostatement- See also control flow
- definite assignment, 421
- specification, 293
- double quote
doubletype- Duff's device, 289
- Dylan, 6
- Eco, Umberto, 118
- Eisenhower, Dwight D., 388
- element type
- Ellis, Margaret A., 6
- Ellison, Shirley, 118
- entity
- Epictetus, 203
- errors
- escapes
- evaluation
- See also execution; initialization; scope
- evaluated, term definition, 317
- expressions
- additive operators, 377
- additive operators for numeric types, 381
- array access, 364
- array assignment, 393
- array creation, 338
- assignment operators, 392
- bitwise binary operators, 388
- bitwise complement, 371
- boolean equality operators, 388
- boolean logical operators, 389
- cast, 372
- compound assignment operators, 398
- conditional operator, 391
- conditional-and operator, 390
- conditional-or operators, 390
- division, 374
- evaluation (continued)
- expressions (continued)
- equality operators, 386
- field access, 341
- instance creation, 334
- integer bitwise operators, 389
- logical binary operators, 388
- logical complement, 371
- method invocation, 345
- method invocation, order of, 356
- multiplication, 373
- multiplicative operators, 373
- numeric comparison, 384
- numeric equality operators, 387
- parenthesized, 330
- postfix, 368
- pre-decrement, 369
- pre-increment, 369
- primary, 327
- reference equality operators, 388
- relational operators, 384
- remainder, 376
- shift operators, 383
- simple assignment operator, 393
- string concatenation, 378
- superclass access, 344
- type comparison, 385
- unary minus, 370
- unary operators, 368
- unary plus, 370
- literals, 328
- order
- result of, term definition, 317
- expressions (continued)
- events
- evolution
- See also binary, compatibility; reuse
- evolution (continued)
- examples
- access control, 106
- fields, methods, and constructors
- default, 108
private, 111protected, 110public, 109
- fields, methods, and constructors
- arrays, 212
- classes,
publicand non-public, 107 - declarations
- default-access methods, constructors, and fields, 108
- exceptions, 224
- fields
- hiding, 181
- vs. overriding, 182
- of variables
- inheritance
- accessing members of inaccessible classes, 152
- class members, 149
- default access, 149
public,protected, andprivateaccess, 150
- multiple, with superinterfaces, 146
- with default access, 149
- with
privateaccess, 151 - with
protectedaccess, 150 - with
publicaccess, 150
- methods
- access control, 106
- examples (continued)
- methods (continued)
- overloading, 181
- overriding, 180
- vs. hiding, 182
- incorrect, 181
- because of
throws, 186
- because of
- large example, 185
- exceptions
- See also binary, compatibility; compile-time errors; errors;
- (chapter), 219
- asynchronous, causes and handling of, 224
- caller, determination of, 222
- causes of, 220
- checked
- constructors, declaring with
throwsclause in method declarations, 175 - defining new exception classes as, 226
Exception, 226- in an instance initializer, 188
- methods, declaring with
throwsclause in method declarations, 175 - in a static initializer, 189
UnsatisfiedLinkException, 236
- constructors, declaring with
- classes
- errors
- exceptions (continued)
- errors (continued)
- example, 224
- handlers
- handling of, 222
- hierarchy, 226
- integer divide by zero, 34
NegativeArraySizeException, 321, 338- never thrown for
NullPointerException, 194- parameters
- precise, 223
RuntimeException, 395- synchronization integrated with mechanism for handling, 220
- exceptions (continued)
- thrown for, narrowing reference conversions, 63
uncaughtExceptionmethod, when invoked, 220- unchecked, 226
- unchecked runtime
- execution
- See also declarations; evaluation; initialization; linking; loading
- (chapter), 229
- order, thread rules, 433
- of statements for their effect, 275
- exit
- exponent
- See value set
- expressions
- See also fields; methods; statements
- (chapter), 317
- abrupt completion of, as reason forabrupt statement completion, 277
- additive operators
- array
- assignment
- expressions (continued)
- bitwise
- boolean
- cast, evaluation, 372
- compound, assignment operators, evaluation, 398
- conditional
- definite assignment and, 412
- division, evaluation, 374
- equality operators, evaluation, 386
- field access, evaluation, 341
- instance creation
- integer bitwise operators, evaluation, 389
- logical
- method invocation
- multiplication *, evaluation, 373
- multiplicative operators *, \xda , %, evaluation, 373
- names
- numeric
- expressions (continued)
- numeric (continued)
- operators
- parenthesized
- post-decrement --
- postfix, evaluation, 367
- post-increment ++
- pre-decrement --
- pre-increment ++
- primary, evaluation of, 327
- reference equality operators ==, !=, evaluation, 388
- relational operators <, >, <=, >=, evaluation, 384
- remainder operator %, evaluation, 376
- run-time checks of, 319
- semantics and evaluation rules, (chapter), 317
- shift operators <<, >>, >>>, evaluation, 383
- simple assignment operator =, evaluation, 393
- statements
- expressions (continued)
extendsclause- See also classes; implements; object-oriented concepts
- in class declaration, specifying direct superclasses with, 142
- in interface declaration, 201
- Feeley, Mark, 224
- fields
- access control
- default, example, 108
private, example, 111protected, example, 110public, example, 109
- access expressions, evaluation, 341
- of an array, 92, 214
- of a class
- access control
- fields (continued)
- of a class (continued)
- non-
static(continued) - re-inheritance of, example, 166
statictransient, 156volatile, 156
- non-
- declarations
- hidden
- accessing with
superkeyword, 344, 345thiskeyword, 283
- accessing with
- of an interface
- names, naming conventions, 115
public, by default in interface declaration, 202- references to, binary file format requirements, 253
- references, active use, 238
- shadowing, 86
- of a class (continued)
- fifth dimension, 339
- files
- Finagle's Law, 219
finalmodifier- See also declarations; modifiers
- anonymous class is always implicitly, 335
- classes
- exception parameter, may not be assigned, 306
- fields
- binary compatibility considerations, 264
- declaration and use, 156, 203
finalby default in, interface declaration, 203- not allowed with
volatile, 158
- formal parameters, 168
- methods
- reasons why constructors cannot be, 191
- finalization
- See also exceptions; linking
- finalizable, as object attribute, 246
finalizemethod, as member ofObjectclass, 45- finalized, as object attribute, 246
- finalizer method calls, unordered nature of, 247
- finalizer-reachable, as object attribute, 246
finallyclause, exception handling use, 223- implementing, 246
- of instances, 245
floattype, 35- See also floating-point
- floating-point
- See also arithmetic; numbers; types
- algebraic identities, limits on use of, 325
floattype, floating-point literal specification, 24, 33
- floating-point (continued)
- flow analysis
- Foote, Samuel, 305
forstatement- form feed
- Forman, Ira, 251
- forward reference
- compile-time error in
- forward references
- FP-strict
- actual arguments, 169
- and addition, 382
- and casts, 372
- classes, 139
- classes, interfaces, methods, constructors and initializers, 319
- compile-time constant is always, 406
- constructors, 191
- and division, 375
- expression
- interfaces, 200
- methods, 173
- and multiplication, 374
- and
returnstatement, 302 - value set conversion within, 65
- Franklin, Benjamin, 229
- Frost, Robert, 199, 310, 315, 445
- Gabriel, Richard P., 6
- Geisel, Theodore, 132
- Gilbert, W. S., 197
- goal symbols
- CompilationUnit, 123
- Input, lexical grammar use, 9
- Goldberg, Adele, 6
gotostatement- See labeled statements
- gradual underflow
- See also exceptions; floating-point; IEEE 754 standard; numbers
- support required for, 38
- grammars
- See also languages; lexical; semantics
- (chapter), 9
- context-free, term definition, 9
- difficulties with, as given in body of Java Language Specification, 449
ifstatement, danglingelsehandling, 284- lexical
- notation, 10
- syntactic, term definition, 10
- Hammerstein, Oscar, II, 133
- Harbison, Samuel, 6
- Harding, Warren G., 307
- hexadecimal
- hiding
- hiding (continued)
- of fields, 136
- hidden class methods, invocation of, example, 184
- of interface field declarations, in superinterfaces, 203
- of interface fields, term definition, 203
- of interface member type declarations, 208
- of interface member types, term definition, 208
- of interfaces, 199
- of member types, term definition, 187
- method
- of methods, 136
- vs. overriding, example, 182
- of types, by member types, 136
- of variables
- hierarchy
- Higginson, Thomas Wentworth, 203
- Hoare, C. A. R., 1, 6
- horizontal tab
- host
- hypothetical analysis
- identifiers
- See also fields; names; scope; variables
- identifiers (continued)
- identity
- IEEE 754 standard, 6
- See also numbers
- floating-point
ifstatements- See also statements
- dangling
else, handling of, 285 - definite assignment, 420
if-thenstatement, specification, 288if-then-elsestatement, specification, 288- specification, 287
- implement
- See also classes;
extendsclause; interfaces implementsclause, 201- term definition, 91, 145
- See also classes;
- import
- See also packages; scope
- automatic, 128
- declarations
- imported types
- as part of a compilation unit, 123
- single-type
- import (continued)
- indexing
- inexact results
- See also numbers
- rounding behavior, 38
- infinity
- inheritance
- See also object-oriented concepts; scope
- in class
- examples of, 149
- of members, 148
- of members, with
public,protected, andprivateaccess, examples, 150 - with default access, example, 149
- of fields
- in class declarations
- in interface declarations
- of members, 90
- of methods
- multiple
- See also superinterfaces
- example, 146
- term definition, 90
- initialization
- See also control flow; linking
- of arrays
- initialization (continued)
- initializers
- See also creation; execution
- array
- arrays, 211
- executing, in
Testclass example initialization, 231 - for fields
- instance
- See instance initializer
- FP-strict, 319
- instance variable, 195
- lacking in a blank final, 50
- local variable
- static, 158, 189
static- variable
- for variables
- inner class
- See also nested class
- anonymous class is always, 335
- inner class (continued)
- input
- instance initializer, 135
- allows field access through super, 344
- anonymous class, 336
- and checked exceptions, 221
- as components of a class body, 147
- containing a throw statement, 304
- definite assignment of variables before, 418
- execution during constructor invocation, 195
- is not a member, 148
- may not contain a return statement, 301
- must be able to complete normally, 189
- overview, 136
- term definition, 188
- and unreachable statements, 310
- when reachable, 311
- instance(s)
- See also classes; interfaces; object-oriented concepts
- creation, 42, 241
- instance(s) (continued)
- creation (continued)
- enclosing
- finalization of, 245
- initializer
- See instance initializer
instanceofoperator- instantiation
- preventing, with
privateconstructors, 139, 197
- preventing, with
- methods
- See methods, non-
static
- See methods, non-
- variables
- See fields, class, non-
static
- See fields, class, non-
instanceofoperator- instantiation
- integers
- See also arithmetic; integral types; numbers
- converting to boolean values, 41
- literals
- operations, 33
- integral types
- integral types (continued)
- interfaces
- See also class(es); fields; methods; packages; subclasses; superclasses; superinterfaces
- (chapter), 199
abstractmethods, 205- accessibility, 105
- as array element types, 210
- binary compatibility considerations, 271
- binary representation
- body, declarations, 202
- and checked exceptions in initializers, 221
Cloneable, implemented by arrays, 214- declarations, 200
- as declared entity, 81
- dependent on a reference type
- directly dependent on a reference type
- fields
- FP-strict, 319
- initialization, 236
java.io.Serializable, implemented by arrays, 214- linking, process description, 233
- loading, 232
- members, 91
- methods
- interfaces (continued)
- methods (continued)
- names
- preparation of, 234
public- references to, binary file format requirements, 255
- in scope of imported type, 85, 125
Serializable, implemented by arrays, 214- superinterfaces
- that depend on themselves, 201
- unloading of, 248
- invocation
- iteration
- See also control structures
continuestatement, specification, 299dostatement, specification, 293forstatement, specification, 295whilestatement, specification, 292
- Java
- digits, term definition, 19
.javasuffix, as name for source files, 122javapackage is always in scope, 125java.langjava.langpackage- letters, term definition, 19
- Java programming language
- See also grammars; languages; lexical; semantics; syntax
- Johnson, Samuel, 13
- Keats, John, 217
- Keene, Sonya E., 6
- Kelvin, Lord (William Thompson), 317
- Kernighan, Brian W., 7
- keywords
- Kiczales, Gregor, 6
- label
- labeled statements
- language
- language (continued)
- Lao-Tsu, 81
- left-hand side
- length
- letters
- See also Unicode character set
- Java, term definition, 19
- lexical
- Liang, Sheng, 233
- life cycle
- See also objects
- of objects, 246
- line terminators, term definition, 16
- linefeed (
LF) - linking, 233
- See also exceptions; execution; initialization; loading; run-time
- classes, process description, 233
- errors, 227
- interfaces, process description, 233
- in
Testclass example, at virtual machine startup, 230
- literals
- See also constants; fields; variables
- boolean, term definition and specification, 25
- charac