public String toExternalForm(){
  if (streamHandler == null) {
    return "unknown protocol(" + protocol + ")://"+ host+ file;
  }
  return streamHandler.toExternalForm(this);
}

public String toExternalForm ( ) { if ( streamHandler == null ) { return "unknown protocol(" + protocol + ")://" + host + file ; } return streamHandler . toExternalForm ( this ) ; }
returns a string containing a concise , human - readable representation of this url .
