question: public String toString ( ) { if ( index == 0 ) { return StringPool . EMPTY ; } char [ ] destination = new char [ length ] ; int start = 0 ; for ( int i = 0 ; i < index ; i ++ ) { String s = array [ i ] ; int len = s . length ( ) ; s . getChars ( 0 , len , destination , start ) ; start += len ; } return new String ( destination ) ; }
target:  Joins together all strings into one.