java对象输入输出流-向文件中写入多个对象并读取出来

readObject()读取到文件最后会有java.io.EOFException异常(读取不到对象)，进行try{}catch(){}捕捉即可

定义一个学生类

package io;

import java.io.Serializable;

public class Student implements Serializable{

    private static final long serialVersionUID = 1L;
    private Integer id;
    private String name;
    public Student() {
    }
    public Student(Integer id, String name) {
        this.id = id;
        this.name = name;
    }
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    @Override
    public String toString() {
        return "Student [id=" + id + ", name=" + name + "]";
    }
    
    
}

写测试方法

package io;

import java.io.EOFException;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

/**
 * 向文件中写入多个对象并读取出来
 */
public class TestObjectStream {
    public static void main(String[] args) throws Exception{
        //向文件中写入对象
        ObjectOutputStream oos=new ObjectOutputStream(new FileOutputStream("student.txt"));
        Student s1=new Student(1,"张三");
        Student s2=new Student(2,"李四");
        Student s3=new Student(3,"王五");
        Student s4=new Student(4,"赵六");
        oos.writeObject(s1);
        oos.writeObject(s2);
        oos.writeObject(s3);
        oos.writeObject(s4);
        oos.close();
        //读取对象
        ObjectInputStream ois=new ObjectInputStream(new FileInputStream("student.txt"));
        while(true){
            try {
                Student stu = (Student) ois.readObject();
                System.out.println(stu);
            } catch (EOFException e) {
                System.out.println("读取完毕");
                break;
            }
        }
        ois.close();
    }
}

运行结果

Student [id=1, name=张三]
Student [id=2, name=李四]
Student [id=3, name=王五]
Student [id=4, name=赵六]
读取完毕

生成了一个文件