对象流

• 对象流:ObjectOutputStream/ObjectOutputStream
  • 增强了缓冲区功能
  • 增强了读写8种基本数据类型和字符串功能
  • 增强了读写对象的功能
    • readObject()从流中读取一个对象
    • writeObject(Object obj)向流中写入一个对象

使用流传输对象的过程称为序列化、返序列化

序列化 ObjectOutputStream

package stream;

import java.io.Serializable;

/*
学生类
 */ 
public class Student implements Serializable {//标记这个类可以序列化
    private String name;
    private int age;
    public Student() {
    }

    public Student(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public int getAge() {
        return age;
    }

    public void setName(String name) {
        this.name = name;
    }

    public void setAge(int age) {
        this.age = age;
    }

    @Override

    public String  toString() {
        return "Student[ name=" + name + ", age=" + age + "]";
    }
}

package stream;

import java.io.FileOutputStream;
import java.io.ObjectOutputStream;

/*
使用ObjectOutputStream实现对象的序列化
要求:序列化必须要实现Serializable接口
 */
public class Demo07 {
    public static void main(String[] args) throws Exception{
        //1.创建对象流
        FileOutputStream fos = new FileOutputStream("e:\\stu.bin");
        ObjectOutputStream oos = new ObjectOutputStream(fos);
        //2.序列化(写入操作)
        Student zhangsan = new Student("张三",20);
        oos.writeObject(zhangsan);
        //3.关闭
        oos.close();
        System.out.println("序列化完毕");
    }
}

反序列化 ObjectInputStream

package stream;

import java.io.FileInputStream;
import java.io.ObjectInputStream;

/*
使用ObjectIntputStream实现反序列化(读取重构对象)
 */
public class Demo08 {
    public static void main(String[] args) throws Exception{
        //1.创建对象流
        FileInputStream fis = new FileInputStream("e:\\stu.bin");
        ObjectInputStream ois = new ObjectInputStream(fis);
        //2.读取文件(反序列化)
        Student s = (Student)ois.readObject();
   
        //3.关闭
        ois.close();
        System.out.println("执行完毕");
        System.out.println(s.toString());
   
    }
}

使用ObjectOutputStream实现对象的序列化
要求:序列化必须要实现Serializable接口
 */
public class Demo07 {
    public static void main(String[] args) throws Exception{
        //1.创建对象流
        FileOutputStream fos = new FileOutputStream("e:\\stu.bin");
        ObjectOutputStream oos = new ObjectOutputStream(fos);
        //2.序列化(写入操作)
        Student zhangsan = new Student("张三",20);
        oos.writeObject(zhangsan);
        //3.关闭
        oos.close();
        System.out.println("序列化完毕");
    }
}
package stream;

import java.io.Serializable;

/*
学生类
 */
public class Student implements Serializable {//标记这个类可以序列化
    private String name;
    private int age;
    public Student() {//在实例化的过程中需要空的构造方法
    }

    public Student(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public int getAge() {
        return age;
    }

    public void setName(String name) {
        this.name = name;
    }

    public void setAge(int age) {
        this.age = age;
    }

    @Override

    public String  toString() {
        return "Student[name=" + name + ", age=" + age + "]";//也可以方便输出
    }
}