java 序列化

需求：使用文件存储和读取对象
方法：实现 Serializable 接口
下面的例子将实现了Serializable接口的Person类添加到ArrayList中，再存储到文件，最后读取并输出。

import java.io.*;
import java.util.ArrayList;

public class TestIO {
    public static void main(String[] args) throws IOException, ClassNotFoundException {
        File file = new File("data.txt");
        ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream(file));
        Person person1 = new Person("Tom", 4);
        Person person2 = new Person("Jerry", 2);
        ArrayList<Person> list1 = new ArrayList<>();
        list1.add(person1);
        list1.add(person2);
        oos.writeObject(list1);
        oos.close();

        ObjectInputStream ois = new ObjectInputStream(new FileInputStream(file));
        ArrayList<Person> list2 = (ArrayList<Person>) ois.readObject();
        ois.close();

        for (Person p : list2) {
            System.out.println(p.toString());
        }
    }
}

class Person implements Serializable {
    private String name;
    private int age;

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

    public String getName() {
        return name;
    }

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

    public int getAge() {
        return age;
    }

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

    @Override
    public String toString() {
        return "姓名：" + name + " 年龄：" + age;
    }
}

输出一：文件
输出二：stdout