对writeexternal方法和readexternal方法进行重写.txt

因此本系统的目标就是让顾客方便快捷和满意的购物。为了达到这一目标

import java.io.*;
public class ObjectExternalization implements Externalizable{
	String s;
	int i;
	public ObjectExternalization(){
       System.out.println("ObjectExternalization Constructor1");
    }
	public ObjectExternalization(String s,int i){
System.out.println("ObjectExternalization Constructor2");
		this.s = s;
		this.i = i;
	}
	public void writeExternal(ObjectOutput out)throws IOException{}
    public void readExternal(ObjectInput in)throws IOException,ClassNotFoundException{}
	public String toString(){
		return "s:"s+"  i:"+i;
	}
	public static void main(String[] args)throws Exception {
ObjectExternalization os = new ObjectExternalization("External",10);
        ObjectOutputStream oops = new ObjectOutputStream(
    		                       new FileOutputStream("out.txt"));
        System.out.println("Saving: ");
        System.out.println(os);
      oops.writeObject(os);
      ObjectInputStream oips = new ObjectInputStream(
               new FileInputStream("out.txt"));
        ObjectExternalization is = (ObjectExternalization)oips.readObject();
        System.out.println("Recovering:");
        System.out.println(is); 
	}
}