HashMap Ex. Source

/*** | | Date : 2010-03-30 | Subject : MapTest2.java | Contance : a | */

 

import java.util.*;

 

class MemberVO{

    //Attirubute

    private String id;

    private String name;

    private int age;

    

    //Constructor

    public MemberVO(){}

    public MemberVO(String id,String name, int age){

        this.id=id;

        this.name=name;

        this.age=age;

    }

 

    //Setter Method()

    public String getId(){

        return id;

    }

 

    //toString Method()

    public String toString(){

        return "MemberVO [id : "+ id+",name : "+ name + ",age : " + age+"]";

        }

    }

 

public class MapTest2{

    public static void main(String[] args) {

 

        //MemberVO 객체 생성

        MemberVO mvo1=new MemberVO("hong1111","홍길동",20);

        MemberVO mvo2=new MemberVO("lee2222","이순신",35);

        MemberVO mvo3=new MemberVO("gang3333","강감찬",40);

        

        //mvo1~mvo3를 map에 넣는다.이 때 id를 key로 한다.

        HashMap<String, MemberVO> map=new HashMap<String, MemberVO>();

 

        map.put(mvo1.getId(),mvo1);

        map.put(mvo2.getId(),mvo2);

        map.put(mvo3.getId(),mvo3);

 

        //조회

        MemberVO rValue=map.get("hong1111");

        System.out.println(rValue);

 

        //id가 2222인 회원이 있는지 체크

        boolean flagkey=map.containsKey("2222");

        System.out.println(flagkey);    //false

 

        //Key값을 모른다고 가정, 현재 관리 중인 회원정보를 모두 출력

        Set<String> key=map.keySet();

        Iterator<String> itr=key.iterator();

        while(itr.hasNext()){

            String keys=itr.next();

            MemberVO mvo= map.get(keys);

            System.out.println(keys + " : "+ mvo);

        }

 

    }//Main End

}//MapTest2 Class End

 

Output

MemberVO [id : hong1111,name : 홍길동,age : 20] false lee2222 : MemberVO [id : lee2222,name : 이순신,age : 35] hong1111 : MemberVO [id : hong1111,name : 홍길동,age : 20] gang3333 : MemberVO [id : gang3333,name : 강감찬,age : 40]