Including comments in Java regular expressions

Question

I have some complex regular expressions which I need to comment for readability and maintenance. The Java spec is rather terse and I struggled for a long time getting this w

Answer 1

See the post by Martin Fowler on ComposedRegex for some more ideas on improving regexp readability. In summary, he advocates breaking down a complex regexp into smaller parts which can be given meaningful variable names. e.g.

String mandatoryName = "([A-Za-z]+)";
String mandatoryWhiteSpace = "\\s+";
String optionalInitial = "([A-Z]\\.)?";
String pattern = mandatoryName + mandatoryWhiteSpace + optionalInitial +
    mandatoryWhiteSpace + mandatoryName;