question: public static < T , U extends InputStream > T withStream ( U stream , @ ClosureParams ( value = FirstParam . class ) Closure < T > closure ) throws IOException { try { T result = closure . call ( stream ) ; InputStream temp = stream ; stream = null ; temp . close ( ) ; return result ; } finally { closeWithWarning ( stream ) ; } }
target:  Allows this input stream to be used within the closure, ensuring that it is flushed and closed before this method returns.