Set集合多种方法遍历

Set集合多种方法遍历

public static void main(String[] args) {
        Set<String> set = new HashSet<>();
        //方法一
        Iterator<String> it = set.iterator();
        while(it.hasNext()) {
            String str = it.next();
            System.out.println(str);
        }
        //方法二 常用推荐
        for (String str : set) {
            System.out.println(str);
        }
        //方法三
        for (Object obj: set) {
            if(obj instanceof Integer){
                int aa= (Integer)obj;
            }else if(obj instanceof String){
                String aa = (String)obj;
            }
        } 
    }