Java Escaping Characters in RegEx

I have the following RegEx email address

[-0-9a-zA-Z.+_]+@[-0-9a-zA-Z.+_]+\.[a-zA-Z]{2,4}

      

        
        
        
      

    

AM is trying to escape characters like below but I am still getting java compilation error. Can someone please help me to avoid the characters in the above RegEx?

String pattern = "\\[-0-9a-zA-Z\\.\\+_\\]\\+@\\[-0-9a-zA-Z\\.\\+_\\]+\\\.\\[a-zA-Z\\]\\{2,4\\}";