Serialization and Deserialization of multiple objects from single file

[hanx]

hey guys, i wrote this java program which is kind of contact directory containing "name" and "id" of persons. what i want to do is store or save multiple contact or object of different value to a single file and retrieve back to the program.. but my luck , i am unable to acheive it.. the output is very different... here is the code of my program :

import java.io.*;
import java.util.*;

public class PersonControl
{
	public static void main(String args[]) throws Exception
	{
		Scanner kb = new Scanner(System.in);// this will be used later 
		PData data = null;
		ObjectInputStream in = null;
		ObjectOutputStream out = null;
		
		out = new ObjectOutputStream(new  FileOutputStream("PData.dat",true));
		data = new PData();
		data.set(101,"Jimmy");
		data.show();
		out.writeObject(data);
		//out.flush();
		data.set(102,"Tony");
		data.show();
		out.writeObject(data);
		//out.flush();
		data.set(103,"cyrus");
		data.show();
		out.writeObject(data);
		//out.flush();
		out.close();
		
		in = new ObjectInputStream(new FileInputStream("PData.dat"));
		PData temp;
		temp = (PData) in.readObject();
		temp.show();
		temp = (PData) in.readObject();
		temp.show();
		temp = (PData) in.readObject();
		temp.show();
		in.close();
		
	}
	
}// end of class



class PData implements Serializable
{
	private String name;
	private int id;
	
	void set(int id_temp, String t_name)
	{
		this.id = id_temp;
		this.name = t_name;
	}
	
	void show()
	{
		System.out.println("ID NO = " + id);
		System.out.println("Name = " + name);
	}
}

The output of the above program is :
C:\jj\object\Personal>java PersonControl
ID NO = 101
Name = Jimmy
ID NO = 102
Name = Tony
ID NO = 103
Name = cyrus
ID NO = 101
Name = Jimmy
ID NO = 101
Name = Jimmy
ID NO = 101
Name = Jimmy
_____________________

You see the first data is only saved and retreived from file but not rest of data.. i want to make like kind of storing multiple information or contact to a single file.. Advice?

[JosAH]

After writing a object to the ObjectOutputStream reset() the stream. Those ObjectOutputStreams think they´re clever by remembering which objects have been written already and they won´t write them again. The reset() method make them forget what they've been writing before.

kind regards,

Jos

[hanx]

hey it worked.. thanks JosAH... u saved my time and brain :)

[JosAH]

hey it worked.. thanks JosAH... u saved my time and brain :)

You're welcome of course and remember: all the details are in the API documentation; never guess or assume anything but always read that stuff.

kind regards,

Jos