public class TestObjectStream {
    @Test
    public void gg() {
        try {
            ObjectInputStream ois = new ObjectInputStream(new FileInputStream(new File("C:\\Users\\Administrator\\IdeaProjects\\untitled\\kkkbbb.txt")));
            Kobe k1 = (Kobe) ois.readObject();
            System.out.println(k1);
            Kobe k2 = (Kobe) ois.readObject();
            System.out.println(k2);
            ois.close();
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

        @Test
        public void gm(){
            try{
    Kobe k1=new Kobe("宋小艾",24);
    Kobe k2=new Kobe("宋艺华",23);
        ObjectOutputStream oos=new ObjectOutputStream(new FileOutputStream("C:\\Users\\Administrator\\IdeaProjects\\untitled\\kkkbbb.txt"));
        oos.writeObject(k1);
        oos.flush();
        oos.writeObject(k2);
        oos.flush();
        oos.close();

    }catch (Exception e){
            e.printStackTrace();
        }
    }

}
class Kobe implements Serializable {//要实现序列化的类必须继承Serializable
    String name;
    Integer score;
    public Kobe(String name, Integer score){
        this.name=name;
        this.score=score;
    }

    @Override
    public String toString() {
        return "Kobe{" +
                "name='" + name + '\'' +
                ", score=" + score +
                '}';
    }
}

Kobe{name='宋小艾', score=24}
Kobe{name='宋艺华', score=23}