question: public static < T > T [ ] requireNonNullElements ( T [ ] array ) { requireNonNull ( array , "The provided array is null." ) ; int len = array . length ; for ( int i = 0 ; i < len ; i ++ ) { if ( array [ i ] == null ) { throw new NullPointerException ( "Item " + i + " in the array " + Arrays . toString ( array ) + " is null" ) ; } } return array ; }
target:  Checks if this array is non null and also that all members are non-null. If a null is detected a NullPointerException is thrown.