java - checking an integer to see if it contains a zero

Question

Given an integer, how could you check if it contains a 0, using Java?

1 = Good
2 = Good
...
9 = Good
10 = BAD!
101 = BAD!
1026 = BAD!
1111 = Good

How can this be done?

Answer 1

Do you mean if the decimal representation contains a 0? The absolute simplest way of doing that is:

if (String.valueOf(x).contains("0"))

Don't forget that a number doesn't "inherently" contain a 0 or not (except for zero itself, of course) - it depends on the base. So "10" in decimal is "A" in hex, and "10" in hex is "16" in decimal... in both cases the result would change.

There may be more efficient ways of testing for the presence of a zero in the decimal representation of an integer, but they're likely to be considerably more involved that the expression above.