Question

I want to replace a content inside some tags, eg:

<p>this it to be replaced</p>

I could extract the content between with groups like this, but can i actually replace the group?

str = str.replaceAll("<p>([^<]*)</p>", "replacement");

Answer 1

Change the regex to this:

(?<=<p>).*?(?=</p>)

ie

str = str.replaceAll("(?<=<p>).*?(?=</p>)", "replacement");

This uses a “look behind” and a “look ahead” to assert, but not capture, input before/after the matching (non-greedy) regex

Just in case anyone is wondering, this answer is different to dacwe’s: His uses unnecessary brackets. This answer is the more elegant 🙂