如何遍历Map操作总结

1          Map<Integer, String> map = new HashMap<Integer, String>();
2          map.put(1, "123");
3          map.put(2, "abc");
4          map.put(3, "ab3");
5          map.put(4, "ab5");
6          map.put(4, "ab6");
7          System.out.println(map.size());

1        Set<Integer> mp = map.keySet();
2        
3        for (Integer key : set) { String str = mp.get(in);
4        System.out.println(in + "     " + str); }

1          Iterator<Map.Entry<Integer, String>> it = map.entrySet().iterator();
2          while (it.hasNext()) {
3               Map.Entry<Integer, String> entry = it.next();
4                 System.out.println("key= " + entry.getKey() + " and value= " + entry.getValue());
5          }

1 for (Map.Entry<Integer, String> entry : map.entrySet()) {
2              System.out.println("key= " + entry.getKey() + " and value= "
3                      + entry.getValue());
4          }

1 for (String v : map.values()) {
2              System.out.println("value= " + v);
3          }