Replace all whitespace at all beginning line and empty lines

I have a string like:

   -------beginning certificate


           2323jjjdcnnjjjsd


        sdsdsdsdsdsdsd

and I would like to transform it in (white spaces should be removed only at beginning of each lines):

-------beginning certificate
2323jjjdcnnjjjsd
sdsdsdsdsdsdsd

I have tried with :

string.replaceAll("^[\n\r\s]*","");

but seems nothing happens.

>Solution :

You can use:

string = string.replaceAll("(?m)^\\h+|\\h+$|^\\R+", "");

RegEx Demo

Breakdown:

• (?m): Enable multiline mode
• ^\\h+: Match 1+ whitespaces at start
• |: ROR
• \\h+$: Match 1+ whitespaces before end
• |: OR
• ^\\R+: Match 1+ line breaks at start