简单的实现却不会

简单的实现却不会

要求假如输入"asdf as df as" 则输出字符串之中最长字符串，
如果两个同时最长如"asdf as df as asdf" 则输出asdf|asdf
如果中间有as/tdf则什么也不输出。
public class Zifu {

 /**
  * @param args
  */
 public static void main(String[] args) {
  // TODO Auto-generated method stub
  String str = "asdfa fasd sf asdfa";
        if (str.indexOf("/") >= 0) {
            System.out.println("format error !");
        } else {
            String s[] = str.split(" ");//-------〉将字符串按照空格拆分成字符串数祖
            int max = 0;
            String ss = "";

            for (int i = 0; i < s.length; i++) { //-----s.length为拆分的叔组长度
                if (max < s[i].length()) {//---------s[i].length()为单个数组字符串长度
                    max = s[i].length();
                }

            }

            for (int i = 0; i < s.length; i++) {
                if (max == s[i].length()) {
                    ss += s[i] + "|";
                }

            }

            System.out.println(ss);
        }
 }