Hello All,
When I'm trying to implement Scanner.nextInt(int radix), I met a problem.
As we all know, Character.MIN_RADIX equals 2 and Character.MAX_RADIX
equals 36, so the parameter radix can not less than 2 or greater than
36, Otherwise that parameter is illegal.
But on RI, when the parameter radix is illegal, there are different
kinds of Exception thrown.
* If the parameter is less than 0 or greater than 36, RI throws a
StringIndexOutOfBoundsException. Obviously this exception depends
an RI's implementation.
* If the parameter equals 1, RI throws an InputMismatchException
with an additional information "The radix 1 is less than the
Character.MIN_RADIX".
* If the parameter equals 0, RI throws a
java.util.regex.PatternSyntaxException whose constructor has three
parameters. And the parameters depends on RI's implementation,
that makes me can not follow RI.
And nothing is documented in the spec. Shall I follow RI's behavior?
Thanks a lot.
Here is the test case to demo this issue.
public void test_nextIntI(){
Scanner s = new Scanner("123 456");
try {
s.nextInt(-1);
fail("Should throw StringIndexOutOfBoundsException");
} catch (StringIndexOutOfBoundsException e) {
// Expected
}
try {
s.nextInt(0);
fail("Should throw PatternSyntaxException");
} catch (PatternSyntaxException e) {
// Expected
}
try {
s.nextInt(1);
fail("Should throw InputMismatchException");
} catch (InputMismatchException e) {
// Expected
}
try {
s.nextInt(40);
fail("Should throw StringIndexOutOfBoundsException");
} catch (StringIndexOutOfBoundsException e) {
// Expected
}
}
--
Richard Liang
China Software Development Lab, IBM
