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Java Programming/Keywords/switch
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is a Java keyword.
It is a branching operation, based on a number. The 'number' must be either , , , or primitive type.
Syntax:
( <integer-var> )
{
<label1>: <statements>;
<label2>: <statements>;
...
<labeln>: <statements>;
: <statements>;
}
When the <integer-var> value match one of the <label>, then:
The statements after the matched label will be executed including the following label's statements, until the end of the block, or until a keyword is reached.
For example:
int var = 3;
switch ( var )
{
case 1:
System.out.println( "Case: 1" );
System.out.println( "Execute until break" );
break;
case 2:
System.out.println( "Case: 2" );
System.out.println( "Execute until break" );
break;
case 3:
System.out.println( "Case: 3" );
System.out.println( "Execute until break" );
break;
case 4:
System.out.println( "Case: 4" );
System.out.println( "Execute until break" );
break;
default:
System.out.println( "Case: default" );
System.out.println( "Execute until break" );
break;
}
The output from the above code is:
Case: 3
Execute until break
The same code can be written with if-else blocks":
int var = 3;
if ( var == 1 ) {
System.out.println( "Case: 1" );
System.out.println( "Execute until break" );
} else if ( var == 2 ) {
System.out.println( "Case: 2" );
System.out.println( "Execute until break" );
} else if ( var == 3 ) {
System.out.println( "Case: 3" );
System.out.println( "Execute until break" );
} else if ( var == 4 ) {
System.out.println( "Case: 4" );
System.out.println( "Execute until break" );
} else {
// -- This is the default part --
System.out.println( "Case: default" );
System.out.println( "Execute until break" );
}
See also:
Java Programming/Keywords/if
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