Java Reference
In-Depth Information
/* ... */
case 11:
System.out.println("Jack");
break;
case 12:
System.out.println("Queen");
break;
case 13:
System.out.println("King");
break;
default:
System.out.println("Invalid Card");
break;
}
Applicability
Failure to include
break
statements can cause unexpected control flow.
The
break
statementattheendofthefinalcaseina
switch
statementmaybeomitted.
By convention, this is the
default
label. The
break
statement serves to transfer control
to the end of the
switch
block. Fall-through behavior also causes control to arrive at the
end of the
switch
block. Consequently, control transfers to the statements following the
switch
blockwithoutregardtothepresenceorabsenceofthe
break
statement.Neverthe-
less,thefinalcaseina
switch
statementshouldendwitha
break
statementinaccordance
with good programming style [Allen 2000].
Exceptionally, when multiple cases require execution of identical code,
break
state-
ments may be omitted from all cases except the last one. Similarly, when processing for
one case is a proper prefix of processing for one or more other cases, the
break
statement
may be omitted from the prefix case. This should be clearly indicated with a comment.
For example:
int card = 11;
int value;
// Cases 11,12,13 fall through to the same case
switch (card) {
// Processing for this case requires a prefix
// of the actions for the following three
case 10:
do_something(card);
