serializing a list of objects into a file in java

Question

I have a list of around 20,000 object, which in turn have a very huge hierarchy. I need to dump the objects into a file, so that i can read it later anytime during my process. Now my problem is, I have worked on Java but not that much on serialization and i dont have that much of knowledge how to do that.

In this case as far as i know, i need to use both Serialization ane De-Serialization. Can anyone please help. Also i can use any new API or normal Java Serialization.

Regards.

Answer 1

Look at this link http://www.java2s.com/Code/Java/File-Input-Output/Objectserialization.htm Its something like this:

Card3 card = new Card3(12, Card3.SPADES);
    System.out.println("Card to write is: " + card);

    try {
      FileOutputStream out = new FileOutputStream("card.out");
      ObjectOutputStream oos = new ObjectOutputStream(out);
      oos.writeObject(card);
      oos.flush();
    } catch (Exception e) {
      System.out.println("Problem serializing: " + e);
    }

    Card3 acard = null;

    try {
      FileInputStream in = new FileInputStream("card.out");
      ObjectInputStream ois = new ObjectInputStream(in);
      acard = (Card3) (ois.readObject());
    } catch (Exception e) {
      System.out.println("Problem serializing: " + e);
    }

    System.out.println("Card read is: " + acard);

Don't forget to implement Serializable interface in all class you want to save and put modifier "transient" at all fields you don't want to save. (e.g. private transient List cache;)