BLOCKS AND STATEMENTS

Labeled Statements

14.6

Statements are thus grammatically divided into two categories: those that

might end in an

if

 statement that has no

else

 clause (a  short

if

 statement ) and

those that definitely do not. Only statements that definitely do not end in a short

if

 statement may appear as an immediate substatement before the keyword

else

in an

if

 statement that does have an

else

 clause. This simple rule prevents the

 dangling

else

  problem. The execution behavior of a statement with the  no

short

if

  restriction is identical to the execution behavior of the same kind of

statement without the  no short

if

  restriction; the distinction is drawn purely to

resolve the syntactic difficulty.

14.5   The Empty Statement

An

empty statement

 does nothing.

EmptyStatement:

;

Execution of an empty statement always completes normally.

14.6   Labeled Statements

Statements may have

label

 prefixes.

LabeledStatement:

Identifier

 :

Statement

LabeledStatementNoShortIf:

Identifier

 :

StatementNoShortIf

The

Identifier

 is declared to be the label of the immediately contained

Statement

.

Unlike C and C++, the Java language has no

goto

 statement; identifier state 

ment labels are used with

break

 ( 14.13) or

continue

 ( 14.14) statements

appearing anywhere within the labeled statement.

A statement labeled by an identifier must not appear anywhere within another

statement labeled by the same identifier, or a compile time error will occur. Two

statements can be labeled by the same identifier only if neither statement contains

the other.

There is no restriction against using the same identifier as a label and as the

name of a package, class, interface, method, field, parameter, or local variable.

Use of an identifier to label a statement does not hide a package, class, interface,

method, field, parameter, or local variable with the same name. Use of an

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