Help required to solve this regex issue

Question

I need to get all characters between a particular expression. For example below is my sample document This is a sample document.

$if ( $variable) FIRST This text can be repeated many times until do while is called. $elseif($variable2) Some sample text follows this. $endif

I need to get all the characters between $if($variable) and $elseif($variable) OR if $elseIf is not there, then between $if($variable) and $else OR if $else is not there then between $if($variable) and $endif. I don't know how to give OR condition if particular expression is not there. I tried giving \\#if\\s*\\((.*?)\\)(.*?)\\#elseif|#else|#endif. But the while(matcher.find()) loop is getting called three times. Is it possible to handle this in regular expression. Only one condition must be satisfied. If that condition is satisfied the other conditions need not be called. Please help me.

Answer 1

Your expression matches either \\#if\\s*\\((.*?)\\)(.*?)\\#elseif or #else or #endif. If you only want an or around the closing statement of the if block then you have to put it into a group like (?:elseif|else|endif).