18일 차 객체를 입출력 하려면 직렬화를 해야한다.

import java.io.Serializable;

public class Car implements Serializable{

private static final long serialVersionUID = -5794225376776071193L;

private String color;

private int speed;

private int mileage;

public String getColor() {

return color;

}

public void setColor(String color) {

this.color = color;

}

public int getSpeed() {

return speed;

}

public void setSpeed(int speed) {

this.speed = speed;

}

public int getMileage() {

return mileage;

}

public void setMileage(int mileage) {

this.mileage = mileage;

}

@Override

public String toString() {

return "Car [color=" + color + ", speed=" + speed + ", mileage=" + mileage + "]";

}

}

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

public class Test2 {

public static void main(String[] args) {

// 최종적으로 사용할 스트림 참조변수를 미리선언

// try구문에서 사용하고 finally블럭에서 닫기 위해서

ObjectInputStream in = null;

ObjectOutputStream out = null;

// FileoutputStream에 직접 ObjectOutputStream을 연결했다

// 중간에 BufferdoutputStream 넣어도 상관없다

try {

out = new ObjectOutputStream(new FileOutputStream("data.bin"));

Car c = new Car();

c.setColor("blue");

c.setSpeed(100);

c.setMileage(5000);

out.writeObject(c);

out.flush();

in = new ObjectInputStream(new FileInputStream("data.bin"));

Car myCar = (Car) in.readObject();

System.out.println(myCar);

} catch (FileNotFoundException e) {

System.out.println("파일이 존재하지 않습니다");

} catch (IOException e) {

// TODO Auto-generated catch block

System.out.println("입출력에 문제가 생겼습니다");

} catch (ClassNotFoundException e) {

// TODO Auto-generated catch block

System.out.println("클래스가 존재하지 않습니다");

} finally {

try {

if (out != null)

out.close();

if (in != null)

in.close();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

}

}

객체를 InputStream, outputStream 하려면 Serializable을 선언해야 한다.