遍历Map集合的方法

创建一个MAP的栗子:

1         Map<String, Integer> tempMap = new HashMap<String, Integer>();
2         tempMap.put("abc", 1);
3         tempMap.put("aoe", 2);
4         tempMap.put("xyz", 3);

方法一:

1         Iterator<Entry<String, Integer>> it = tempMap.entrySet().iterator();
2         while (it.hasNext()) {
3             Entry<String, Integer> entry = it.next();
4             Object key = entry.getKey();
5             Object value = entry.getValue();
6             System.out.println("key=" + key + " value=" + value);
7         }

方法二:

1         for (Map.Entry<String, Integer> entry : tempMap.entrySet()) {
2             String key = entry.getKey().toString();
3             String value = entry.getValue().toString();
4             System.out.println("key=" + key + " value=" + value);
5         }

方法三:

1         for (Iterator<String> i = tempMap.keySet().iterator(); i.hasNext();) {
2             Object obj = i.next();
3             System.out.println(obj);
4             System.out.println("key=" + obj + " value=" + tempMap.get(obj));
5         }
6         for (Iterator<Integer> i = tempMap.values().iterator(); i.hasNext();) {
7             Object obj = i.next();
8             System.out.println(obj);
9         }

方法四:

1         for (Object o : tempMap.keySet()) {
2             System.out.println("key=" + o + " value=" + tempMap.get(o));
3         }