This rule applies whenever an if
statement is followed by one or more else if
statements; the final else if
should be followed by an else
statement.
The requirement for a final else
statement is defensive programming.
The else
statement should either take appropriate action or contain a suitable comment as to why no action is taken. This is
consistent with the requirement to have a final default
clause in a switch
statement.
Noncompliant code example
if (x == 0) {
doSomething();
} else if (x == 1) {
doSomethingElse();
}
Compliant solution
if (x == 0) {
doSomething();
} else if (x == 1) {
doSomethingElse();
} else {
throw new MyException('Illegal state');
}
Exceptions
When all branches of an if
-else if
end with return
, break
or throw
, the code that
comes after the if
implicitly behaves as if it was in an else
clause. This rule will therefore ignore that case.