无重复字符串的长度

给定一个字符串，请你找出其中不含有重复字符串的「最长字符串」的长度
例如：asdcsasdecxc
长度：6

  
 @Test
    public void test(){
        String data = "asdcsasdecxc";
        Map<Character,Integer> has = Maps.newHashMap();
        HashSet a = new HashSet<>();
        Integer max = 0;
        for (int i = 0; i< data.length(); i++){
            Character tmp = data.charAt(i);
            if (has.containsKey(tmp)){
                max = Math.max(max, i - has.get(tmp));
                has.replace(tmp, i);
            }
            has.put(tmp, i);
        }
        System.out.println(max);
    }