Java pattern repeated Capturing Groups

Question

I have the following String

52x10x20x30x40

The string can be extended but with the same pattern and there will be other strings on both sides of it: for example

"Hello something 52x10x20x30x40 bla bla bla"

i want to capture all 2-digits.

I have the following regex

Pattern.compile("(\\d\\d)([x]\\d\\d)+");

But with this regex i only get the following groups:

1: 52
2: x40

Answer 1

Why not simply:

"52x10x20x30x40".split("x");

?

Forgot to mention that there can be other strings on both sides.

You could search for "\\d{2}(x\\d{2})+", and use split("x") on the match.

Answer 2

Regex doesn't support variable group lengths.

Use a split method instead, e.g. Guava's Splitter:

Iterable<String> tokens = Splitter.on('x').split(str);

Answer 3

If you just want to capture all two digit numbers you could use this expression:

(?<!\d)(\d\d)(?!\d)

Usually you can only get the last substring that a repeated capturing group matches. (.NET regex differs in this regard.)