Map集合的两种迭代方法

直接上代码

    @Test
    public void test3(){
        
        Map<Integer, String> m = new HashMap<Integer, String>();
        m.put(1, "one");
        m.put(2, "two");
        m.put(3, "three");
        Set<Map.Entry<Integer, String>> set = m.entrySet();
        Iterator<Map.Entry<Integer, String>> i = set.iterator();
        while(i.hasNext()){
            Entry<Integer, String> entry = i.next();
            int key = entry.getKey();
            String value = entry.getValue();
            System.out.println(key+"="+value);
            
        }
        
    }
    
    @Test
    public void test4(){
        
        Map<Integer, String> m = new HashMap<Integer, String>();
        m.put(1, "one");
        m.put(2, "two");
        m.put(3, "three");
        Set<Integer> set = m.keySet();
        Iterator<Integer> i = set.iterator();
        while(i.hasNext()){
            int key = i.next();
            String value = m.get(key);
            System.out.println(key+"="+value);
        }
    }