遍历Map集合的方法

创建一个MAP的栗子:

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

方法一:

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

方法二:

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

方法三:

         for (Iterator<String> i = tempMap.keySet().iterator(); i.hasNext();) {
             Object obj = i.next();
             System.out.println(obj);
             System.out.println("key=" + obj + " value=" + tempMap.get(obj));
         }
         for (Iterator<Integer> i = tempMap.values().iterator(); i.hasNext();) {
             Object obj = i.next();
             System.out.println(obj);
         }

方法四:

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