Question

im new to Regular Expressions in general and I start to read more about them , so be gentle 🙂

I want to find all words that begins with my(" or my('. The word itself can contain underscores, characters, digits, basically any char. But it should end with ") or ').

So I tried the following:

Pattern.compile("_(\"(.*)\")"); // for underscores first, instead of my

and

Pattern.compile("(my)(\"(.*)\")");

But this give me other things back as well, and I can’t see why and where I making the thinking mistake…

Thanks

Answer 1

If you want to match my("xxx") and my('xxx') but not my("xxx') then try the following expression:

my\((?:"[^"]*"|'[^']*')\)

Here’s a short breakdown of the expression:

• my\(...\) means the match should start with my( and end with )
• (?:"[^"]*"|'[^']*') means a sequence of characters surrounded by either double quotes or single quotes (therefore the character class means “any character not being a double quote” or “any character not being a single quote”)

Edit:

The problem with the expression (my)("(.*)") is, that it is greedy and the match would start at my(" but end on the last ") due to the .* which matches anything. Thus it would match my("xxx") your("yyy") because .* matches xxx") your("yyy.

For more information on regular expressions see http://www.regular-expressions.info