IO操作之ObjectInputStream与ObjectOutputStream

之前写过DataInputStream和DataOutputStream，使用这两个类可以对java基本数据类型进行序列化和反序列化。

本篇再来两个新东西：ObjectInputStream，ObjectOutputStream，这二位不但能对java基本数据类型进行操作，还可以直接干对象，使用起来也更方便。不过，值得注意的是，被干的对象需要实现Serializable接口。

请看下面两个示例

public class Student implements Serializable {
    private int id;
    private String name;
    private long age;
    private boolean gender;

    public Student(int id, String name, long age, boolean gender) {
        this.id = id;
        this.name = name;
        this.age = age;
        this.gender = gender;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

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

    public long getAge() {
        return age;
    }

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

    public boolean isGender() {
        return gender;
    }

    public void setGender(boolean gender) {
        this.gender = gender;
    }

    @Override
    public String toString() {
        return "Student{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", age=" + age +
                ", gender=" + gender +
                '}';
    }
}

示例1：

 @Test
    public void testObjectStream() throws Exception {
        String fileName = "E:\\360downloads\\wpcache\\srvsetwp\\student2.txt";
        //对象输出流
        OutputStream outputStream = new FileOutputStream(fileName);
        ObjectOutputStream objectOutputStream = new ObjectOutputStream(outputStream);
        Student student = new Student(1, "李连杰", 12, true);
        objectOutputStream.writeObject(student);
        objectOutputStream.close();
        outputStream.close();

        //对象输入流
        FileInputStream fileInputStream = new FileInputStream(fileName);
        ObjectInputStream objectInputStream = new ObjectInputStream(fileInputStream);
        Student o = (Student) objectInputStream.readObject();
        System.out.println(o);  //Student{id=1, name='李连杰', age=12, gender=true}
        objectInputStream.close();
        fileInputStream.close();
    }

示例2：

   @Test
    public void testObjectStreamPrimary() throws Exception {
        String fileName = "E:\\360downloads\\wpcache\\srvsetwp\\student2.txt";
        //对象输出流
        OutputStream outputStream = new FileOutputStream(fileName);
        ObjectOutputStream objectOutputStream = new ObjectOutputStream(outputStream);
        Student student = new Student(1, "李连杰", 12, true);
        objectOutputStream.writeInt(student.getId());
        objectOutputStream.writeUTF(student.getName());
        objectOutputStream.writeLong(student.getAge());
        objectOutputStream.writeBoolean(student.isGender());
        objectOutputStream.close();
        outputStream.close();

        //对象输入流
        FileInputStream fileInputStream = new FileInputStream(fileName);
        ObjectInputStream objectInputStream = new ObjectInputStream(fileInputStream);
        int id = objectInputStream.readInt();
        String name = objectInputStream.readUTF();
        long age = objectInputStream.readLong();
        boolean gender = objectInputStream.readBoolean();
        student = new Student(id, name, age, gender);
        System.out.println(student);
        objectInputStream.close();
        fileInputStream.close();
    }