老师好像没教怎么一次读取文件中的全部对象

package homework;

import java.io.Serializable;

public class Product implements Serializable {
private String ID;
private String name;
private String categories;
private float price;
public Product(String iD, String name, String categories, float price) {
	super();
	ID = iD;
	this.name = name;
	this.categories = categories;
	this.price = price;
}
@Override
public String toString() {
	return "Product [ID=" + ID + ", name=" + name + ", categories=" + categories + ", price=" + price + "]";
}


	
	
	
	
	
	
}

package homework;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

public class Test {

public static void main(String[] args) {

Product iphone=new Product("123","iphone","telephone",4888f);

Product ipad=new Product("234","ipad","computer",5088f);

Product macbook=new Product("345","macbook","computer",10688);

Product iwatch=new Product("256","iwatch","watch",4799);

try {

FileOutputStream fos=new FileOutputStream("object.txt");

    ObjectOutputStream oos=new ObjectOutputStream(fos);

    FileInputStream fis=new FileInputStream("object.txt");

    ObjectInputStream ois=new ObjectInputStream(fis);

    oos.writeObject(iphone);

    oos.writeObject(ipad);

    oos.writeObject(macbook);

    oos.writeObject(iwatch);

        oos.flush();

Object n=null;

        while((n=ois.readObject())!=null) {

        Product products=(Product)ois.readObject();

        System.out.println(products);

        }

ois.close();

oos.close();

fos.close();

    fis.close();

} catch (FileNotFoundException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}catch (ClassNotFoundException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

}

自己尝试了下，发现报错

Product [ID=234, name=ipad, categories=computer, price=5088.0]

Product [ID=256, name=iwatch, categories=watch, price=4799.0]

java.io.EOFException

at java.base/java.io.ObjectInputStream$BlockDataInputStream.peekByte(ObjectInputStream.java:3062)

at java.base/java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1561)

at java.base/java.io.ObjectInputStream.readObject(ObjectInputStream.java:430)

at homework.Test.main(Test.java:28)