How to Write an Object to File in Java

In this example we will show how to write an object to file in Java.

Source Code

package com.beginner.examples;

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

public class WriteObjctToFile2 {

	public static void main(String[] args) {
		try {
			
			HashMap map = new HashMap();
			map.put("name", "foolfish");
			
			List list = new ArrayList();
			list.add("hello");
			list.add("everyone");
			FileOutputStream outStream = new FileOutputStream("E:tmpTest.txt");
			ObjectOutputStream objectOutputStream = new ObjectOutputStream(outStream);
			
			objectOutputStream.writeObject(map);
			objectOutputStream.writeObject(list);
			outStream.close();
			System.out.println("successful");
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}

Output:

successful

References

Imported packages in Java documentation: