Deal with transient in Object Serialization : Object Serialization « File « Java Tutorial

import java.util.Date;

public class MainClass {
  public static void main(String[] args) throws Exception {
    User a = new User("A", "B");
    System.out.println("logon a = " + a);
    ObjectOutputStream o = new ObjectOutputStream(new FileOutputStream("User.out"));

    Thread.sleep(1000); // Delay for 1 second

    ObjectInputStream in = new ObjectInputStream(new FileInputStream("User.out"));
    System.out.println("Recovering object at " + new Date());
    a = (User) in.readObject();
    System.out.println("logon a = " + a);


class User implements Serializable {
  private Date date = new Date();

  private String username;

  private transient String password;

  public User(String name, String pwd) {
    username = name;
    password = pwd;

  public String toString() {
    String pwd = (password == null) ? "(n/a)" : password;
    return "logon info: \n   username: " + username + "\n   date: " + date + "\n   password: "
        + pwd;

11.38.Object Serialization
11.38.1.Conditions for Serialization
11.38.2.Storing Objects in a File
11.38.3.Reading an Object From a File
11.38.4.Serializing Variations on an Object
11.38.5.Writing objects sequentially to a file with class ObjectOutputStream
11.38.6.Read a file of objects sequentially and displays each record
11.38.7.Only parent class is Serializable
11.38.8.Saving and restoring the state of classes
11.38.9.Class combination Serialization
11.38.10.Controlling serialization by adding your own
11.38.11.Serialization with ObjectInputStream and ObjectOutputStream
11.38.12.Deal with transient in Object Serialization
11.38.13.Serialization Utilities