import java.util.Collection;

import java.util.HashMap;

import java.util.Iterator;

import java.util.Map;

import java.util.Set;/**

*

* @author Administrator

*/

public class StuMapTest { public static void main(String[] args) {

Map<String, Student> map = new HashMap<String, Student>();

Student s1 = new Student("001", "呂布", 30);

Student s2 = new Student("002", "趙雲", 25);

Student s3 = new Student("003", "典韋", 33);

map.put("1", s1);

map.put("2", s2);

map.put("3", s3);

byValues(map);

keySet(map);

entrySet(map);

}

//entrySet方法遍歷

private static void entrySet(Map<String, Student> map){

Set<Map.Entry<String,Student>> set = map.entrySet();

for (Iterator<Map.Entry<String, Student>> i = set.iterator(); i.hasNext();) {

System.out.println(i.next().getValue()); }

}

//keySet方法遍歷

private static void keySet(Map<String, Student> map){

Set<String> set = map.keySet();

for (Iterator<String> i = set.iterator(); i.hasNext();) {

System.out.println(map.get(i.next()));

}

}//values方法遍歷

private static void byValues(Map<String, Student> map) {

Collection c = map.values();

for (Iterator<Student> i = c.iterator(); i.hasNext();) {

System.out.println(i.next()); }

}

}//定義一個student類

class Student {

private String id;

private String name;

private int age; public Student(String id, String name, int age) {

this.id = id;

this.name = name;

this.age = age;

} @Override

public String toString() {

return new StringBuilder().append(id).append(" ").append(name).append(" ").append(age).toString();

}

}