How do I remove trailing whitespace using a regular expression?

Question

I want to remove trailing white spaces and tabs from my code without removing empty lines.

I tried:

\\s+$

and:

([^\\n]         


        

Answer 1

Regex to find trailing and leading whitespaces:

^[ \t]+|[ \t]+$

Answer 2

To remove trailing white space while ignoring empty lines I use positive look-behind:

(?<=\S)\s+$

The look-behind is the way go to exclude the non-whitespace (\S) from the match.

Answer 3

Try just removing trailing spaces and tabs:

[ \t]+$

Answer 4

In Java:

String str = "    hello world  ";

// prints "hello world" 
System.out.println(str.replaceAll("^(\\s+)|(\\s+)$", ""));