java for map

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	public static void main(String[] args) {
		Map tempMap = new HashMap();
		tempMap.put("a", 1);
		tempMap.put("b", 2);
		tempMap.put("c", 3);
		// JDK1.4中
		// 遍历方法一 hashmap entrySet() 遍历
		System.out.println("----------方法一----------");
		Iterator it = tempMap.entrySet().iterator();
		while (it.hasNext()) {
			Map.Entry entry = (Map.Entry) it.next();
			Object key = entry.getKey();
			Object value = entry.getValue();
			System.out.println("key=" + key + " value=" + value);
		}
		
		// JDK1.5中,应用新特性For-Each循环
		// 遍历方法二
		System.out.println("----------方法二----------");
		for (Map.Entry entry : tempMap.entrySet()) {
			String key = entry.getKey().toString();
			String value = entry.getValue().toString();
			System.out.println("key=" + key + " value=" + value);
		}
		
		// 遍历方法三 hashmap keySet() 遍历
		System.out.println("----------方法三----------");
		for (Iterator i = tempMap.keySet().iterator(); i.hasNext();) {
			Object obj = i.next();
			System.out.println(obj);// 循环输出key
			System.out.println("key=" + obj + " value=" + tempMap.get(obj));
		}
		for (Iterator i = tempMap.values().iterator(); i.hasNext();) {
			Object obj = i.next();
			System.out.println(obj);// 循环输出value
		}
		
		// 遍历方法四 treemap keySet()遍历
		System.out.println("----------方法四----------");
		for (Object o : tempMap.keySet()) {
			System.out.println("key=" + o + " value=" + tempMap.get(o));
		}

		// java如何遍历Map  map = new HashMap ();
		System.out.println("1111");
		System.out.println("java遍历Map  map = new HashMap ();");
		Map map = new HashMap();
		Set keys = map.keySet();
		Iterator iterator = keys.iterator();
		while (iterator.hasNext()) {
			String key = iterator.next();
			ArrayList arrayList = map.get(key);
			for (Object o : arrayList) {
				System.out.println(o + "遍历过程");
			}
		}
		
		System.out.println("2222");
		Map mapList = new HashMap();
		for (Map.Entry entry : mapList.entrySet()) {
			String key = entry.getKey().toString();
			List values = (List) entry.getValue();
			for (String value : values) {
				System.out.println(key + " --> " + value);
			}
		}
	}
  http://qsfwy.iteye.com/blog/438021

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