Java - 如何遍历Map中的内容
Map的遍历很简单，不过在JDK1.5中有新的方法可以遍历，相信有很多外包的同仁用的还是JDK1.4版吧，呵呵，这里就分别写出如何在JDK1.5(1.6..)和JDK1.4中遍历Map。
JDK1.4中代码如下：
public static void main(String[] args) {Person numOne = new Person();numOne.setName("Lusifer");numOne.setAge(25);Person numTwo = new Person();numTwo.setName("Main");numTwo.setAge(25);Person numThree = new Person();numThree.setName("Ted");numThree.setAge(25);try {numOne.setBrithday(new SimpleDateFormat("yyyy-MM-dd").parse("1986-07-31"));numTwo.setBrithday(new SimpleDateFormat("yyyy-MM-dd").parse("1986-08-31"));numThree.setBrithday(new SimpleDateFormat("yyyy-MM-dd").parse("1989-08-31"));} catch (ParseException e) {e.printStackTrace();}Map map = new HashMap();map.put("numOne", numOne);map.put("numTwo", numTwo);map.put("numThree", numThree);Iterator it = map.entrySet().iterator();while (it.hasNext()) {Map.Entry entry = (Map.Entry) it.next();//Object key = entry.getKey();//Object value = entry.getValue();Person p = (Person) entry.getValue();System.out.println(p.getName());}}public static void main(String[] args) {Person numOne = new Person();numOne.setName("Lusifer");numOne.setAge(25);Person numTwo = new Person();numTwo.setName("Main");numTwo.setAge(25);Person numThree = new Person();numThree.setName("Ted");numThree.setAge(25);try {numOne.setBrithday(new SimpleDateFormat("yyyy-MM-dd").parse("1986-07-31"));numTwo.setBrithday(new SimpleDateFormat("yyyy-MM-dd").parse("1986-08-31"));numThree.setBrithday(new SimpleDateFormat("yyyy-MM-dd").parse("1989-08-31"));} catch (ParseException e) {e.printStackTrace();}Map<String, Object> map = new HashMap<String, Object>();map.put("numOne", numOne);map.put("numTwo", numTwo);map.put("numThree", numThree);//加入了foreach的特性，这里方便多了for (Object o : map.keySet()) {Person p = (Person) map.get(o);System.out.println(p.getName());}}