Match a string against multiple regex patterns

Question

I have an input string.

I am thinking how to match this string against more than one regular expression effectively.

Example Input: ABCD 

I'd like to match against these reg-ex patterns, and return true if at least one of them matches:

[a-zA-Z]{3}  ^[^\\d].*  ([\\w&&[^b]])* 

I am not sure how to match against multiple patterns at once. Can some one tell me how do we do it effectively?

Answer 1

If you have just a few regexes, and they are all known at compile time, then this can be enough:

private static final Pattern   rx1 = Pattern.compile("..."),   rx2 = Pattern.compile("..."),   ...;  return rx1.matcher(s).matches() || rx2.matcher(s).matches() || ...; 

If there are more of them, or they are loaded at runtime, then use a list of patterns:

final List<Pattern> rxs = new ArrayList<>();   for (Pattern rx : rxs) if (rx.matcher(input).matches()) return true; return false; 

Answer 2

you can make one large regex out of the individual ones:

[a-zA-Z]{3}|^[^\\d].*|([\\w&&[^b]])*