question: public static String explode ( Collection < String > collection , String delimiter ) { StringBuilder sb = new StringBuilder ( ) ; if ( ! collection . isEmpty ( ) ) { Iterator < String > i = collection . iterator ( ) ; sb . append ( i . next ( ) ) ; while ( i . hasNext ( ) ) { sb . append ( delimiter ) ; sb . append ( i . next ( ) ) ; } } return sb . toString ( ) ; }
target:  Returns the tokens of a collection concanated to a delimited by the given delimiter.