■ Labels have the same naming rules as variables, except for their ending colon. See identifiers.
■ You cannot create a freestanding label. Labels must go on a statement.
■ You cannot put a label on a declaration statement - only on flow control statements like if, for, whilež and do. i.e.
The following code will not compile. The label must go on the for statement:
label:
int x = 0;
for
( ; x < 3; x++ ) {
if
(x == 1) { System.out.print( x ); break; }
if
(x == 2) { break label; }
}
■ You can repeat statement label names in a Java program, as long as they are not nested. i.e.
This snippet containing identical labels compiles and runs successfully.
labelA: for (int x = 0; x < 3; x++ ) {
if
(x == 1) break label1;
System.out.println(x);
}
labelA: switch ( x ) {
case
0: break label1;
}