package javabean;import java.io.*;public class UserBean implements Serializable {  private String username;  public UserBean() {  }  private void readObject(ObjectInputStream ois) throws ClassNotFoundException, IOException {    ois.defaultReadObject();  }  private void writeObject(ObjectOutputStream oos) throws IOException {    oos.defaultWriteObject();  }  public String getUsername() {    return username;  }  public void setUsername(String username) {    this.username = username;  }}