Java Tutorial/Language/transient

Demonstrates the "transient" keyword

   <source lang="java">

import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.io.Serializable; 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"));
   o.writeObject(a);
   o.close();
   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;
 }

}</source>