How to Read and Write Object to a File in Java

In this example we will show how to write a class to a file and read it in Java.

Source Code

1)Create a new class Student

package com.beginner.examples;
import java.io.Serializable;

public class Student implements Serializable {
    private String name;
    private static final long serialVersionUID = 1 L;

    private int age;

    public Student() {}
    public Student(String name, int age) {
        this.name = name;
        this.age = age;

    }
    public String toString() {
        return "Name: " + this.name + "nAge: " + this.age;

    }
}

package com.beginner.examples;

import java.io.File;

import java.io.FileInputStream;
import java.io.ObjectInputStream;

import java.io.FileOutputStream;
import java.io.IOException;

import java.io.ObjectOutputStream;

public class WriteObjectToFileExample {

	/**
	 * @param args
	 */
	public static void main(String[] args) {

		Student stu = new Student("Tom", 20);
		try {
			FileOutputStream fos = new FileOutputStream(new File("MyText.txt"));
			ObjectOutputStream oos = new ObjectOutputStream(fos);
			oos.writeObject(stu);
			fos.close();
			oos.close();
			FileInputStream fis = new FileInputStream(new File("MyText.txt"));
			ObjectInputStream ois = new ObjectInputStream(fis);
			Student s = (Student) ois.readObject();
			System.out.println(s.toString());

		} catch (IOException e) {
			// TODO: handle exception
			System.out.println(e.toString());
		} catch (Exception e) {
			// TODO: handle exception
		}

	}

}

Output:

Name: Tom
Age: 20

##3.Tipe
it is mandatory that the concerned class implements Serializable interface

References

Imported packages in Java documentation: