去掉字符串数组中重复字符,将字符串数组转为字符串

String group = "wer,der,wer,dd,der";

String[] str = group.split(",");Set set = new TreeSet();for (int i = 0; i < str.length; i++) {    set.add(str[i]);}str = (String[]) set.toArray(new String[0]);   //将set中的内容放入参数数组中，当参数数组的长度小于set的元素个数时，会自动扩充数组的长度以适应set的长度//将字符数组转为字符串 StringBuffer sb = new StringBuffer();for(int i = 0; i < str.length; i++){    sb.append(str[i]);}group = sb.toString();