Wildcard matching in Java

Question

I\'m writing a simple debugging program that takes as input simple strings that can contain stars to indicate a wildcard match-any

*.wav  // matches 

        

Answer 1

Just escape everything - no harm will come of it.

    String input = "*.wav";
    String regex = ("\\Q" + input + "\\E").replace("*", "\\E.*\\Q");
    System.out.println(regex); // \Q\E.*\Q.wav\E
    System.out.println("abcd.wav".matches(regex)); // true

Or you can use character classes:

    String input = "*.wav";
    String regex = input.replaceAll(".", "[$0]").replace("[*]", ".*");
    System.out.println(regex); // .*[.][w][a][v]
    System.out.println("abcd.wav".matches(regex)); // true

It's easier to "escape" the characters by putting them in a character class, as almost all characters lose any special meaning when in a character class. Unless you're expecting weird file names, this will work.