Java PatternSyntaxException: Illegal repetition on string substitution?

Question

I am trying to write a method that will accept a String, inspect it for instances of certain tokens (e.g. ${fizz}, ${buzz}, ${fo

Answer 1

In ${fizz}

{ is an indicator to the regex engine that you are about to start a repetition indicator, like {2,4} which means '2 to 4 times of the previous token'. But {f is illegal, because it has to be followed by a number, so it throws an exception.

You need to escape all regex metacharacters (in this case $, { and }) (try using http://docs.oracle.com/javase/6/docs/api/java/util/regex/Pattern.html#quote(java.lang.String) ) or use a different method that substitutes a string for a string, not a regex for a string.