Map 객체 연습

예제)

예제

package ex;

public class StudentDTO {
	private int studentNumber;
	private String studentName;
	private String studentMajor;
	private String studentMoblie;
		
	public StudentDTO () {
		
	}

	public int getStudentNumber() {
		return studentNumber;
	}

	public void setStudentNumber(int studentNumber) {
		this.studentNumber = studentNumber;
	}

	public String getStudentName() {
		return studentName;
	}

	public void setStudentName(String studentName) {
		this.studentName = studentName;
	}

	public String getStudentMajor() {
		return studentMajor;
	}

	public void setStudentMajor(String studentMajor) {
		this.studentMajor = studentMajor;
	}

	public String getStudentMoblie() {
		return studentMoblie;
	}

	public void setStudentMoblie(String studentMoblie) {
		this.studentMoblie = studentMoblie;
	}
	

	public String toString () {
		return studentNumber +"\t"+ studentName +"\t"+ studentMajor +"\t"+ studentMoblie;
	}

}

기본생성자 Student 생성하고 나머지 변수들은 get set 메소드를 생성하고 toString으로 출력 준비를 한다.

package ex;

import java.util.*;
import java.util.Map;

public class StudentMain {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		
		Map<Integer, StudentDTO> student = new HashMap<>();
		StudentDTO s1 = new StudentDTO();
		s1.setStudentNumber(1111);
		s1.setStudentName("김자바");
		s1.setStudentMajor("컴퓨터공학");
		s1.setStudentMoblie("010-1111-1111");
		student.put(1, s1);
		
		StudentDTO s2 = new StudentDTO();
		s2.setStudentNumber(2222);
		s2.setStudentName("이자바");
		s2.setStudentMajor("경영학");
		s2.setStudentMoblie("010-2222-2222");
		student.put(2, s2);
		
		StudentDTO s3 = new StudentDTO();
		s3.setStudentNumber(3333);
		s3.setStudentName("박자바");
		s3.setStudentMajor("전자공학");
		s3.setStudentMoblie("010-3333-3333");
		student.put(3, s3);
		
	
		System.out.printf("번호(id)\t학번\t이름\t전공\t전화번호\n");
		System.out.println("================================================");
		for(int key:student.keySet()) {
			System.out.println(key+"\t"+student.get(key).toString());
			
		}
		
		

		
	}

}

Student 타입의 s1 , s2 , s3 ... 으로 정보를 담아 출력하기 위해 set을 이용해 정보를 담아넣고

 

put 메소드를 사용해 key값에 맞춰 객체를 설정해주었다.

 

그리고 for문으로 keyset 메소드를 사용해 출력하여 다음과 같게 출력되었다.

 

출력물