Question

I am lost when it comes to building regex strings. I need a regular expression that does the following.

I have the following strings:

[~class:obj]
[~class|class2|more classes:obj]
[!class:obj]
[!class|class2|more classes:obj]
[?method:class]
[text]

A string can have multiple of whats above. Example string would be "[if] [!class:obj]"

I want to know what is in between the [] and broken into match groups. For example, the first match group would be the symbol if present (~|!|?) next what is before the : so that could be class or class|class2|etc… then what is on the right of the : and stop before the ]. There may be no : and what goes before it, but just something between the [].

So, how would I go about writing this regex? And is it possible to give the match group names so I know what it matched?

This is for a java project.

Answer 1

If you’re sure enough of your inputs, you can probably use something like /\[(\~|\!|\?)?(?:((?:[^:\]]*?)+):)?([^\]]+?)\]/. (to translate that into Java, you’ll want to escape the backslashes and use quotation marks instead of forward slashes)