JavaI/O系统2

数据流：

DataInputStream，DataOutputStream。可以用于与计算机无关的格式读写java的基本数据类型以及String对象

对象流：

ObjectInputStream，ObjectOutputStream.

序列化：保存内存中对象的“全景图”。

为了实现对象序列化，对应的类必须实现Serializable接口。

Serializable接口中没有定义任何的方法，称之为“标记接口”。

如果加上了一个transient修饰符，该属性的值将不被序列化。

反序列化：使用ObjectInputStream类，将字节序列还原成对象的过程。

 package com.lovo.day2;

 import java.io.IOException;
 import java.io.Serializable;
 import java.util.Date;

 public class Student implements Serializable {

     private static final long serialVersionUID = 4282130869653374904L;

     private String name;
     private int age;
     private boolean sex;
     private double money;
     private Date birth;
     private Course course;

     public Student(String name, int age, boolean sex, double money, Date birth,
             Course course) {
         super();
         this.name = name;
         this.age = age;
         this.sex = sex;
         this.money = money;
         this.birth = birth;
         this.course = course;
     }

     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;
     }

     public boolean isSex() {
         return sex;
     }

     public void setSex(boolean sex) {
         this.sex = sex;
     }

     public double getMoney() {
         return money;
     }

     public void setMoney(double money) {
         this.money = money;
     }

     public Date getBirth() {
         return birth;
     }

     public void setBirth(Date birth) {
         this.birth = birth;
     }

     public Course getCourse() {
         return course;
     }

     public void setCourse(Course course) {
         this.course = course;
     }

     @Override
     public String toString() {
         return "Student [name=" + name + ", age=" + age + ", sex=" + sex
                 + ", money=" + money + ", birth=" + birth + ", course="
                 + course + "]";
     }

  /*   private void readObject(java.io.ObjectInputStream in) throws IOException,
             ClassNotFoundException {
         System.out.println("读");
         this.name = in.readUTF();
         this.age = in.readInt();
         this.sex = in.readBoolean();
         this.course = (Course) in.readObject();
         this.money = in.readDouble();
     }

     private void writeObject(java.io.ObjectOutputStream out) throws IOException {
         System.out.println("写");
         out.writeUTF(this.name);
         out.writeInt(this.age);
         out.writeBoolean(this.sex);
         out.writeObject(course);
         out.writeDouble(this.money);
     }
   */
 }

 package com.lovo.day2;

 import java.io.Serializable;

 public class Course implements Serializable {

     private static final long serialVersionUID = 1L;

     private int code;
     private String name;

     public int getCode() {
         return code;
     }

     public void setCode(int code) {
         this.code = code;
     }

     public String getName() {
         return name;
     }

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

     public Course(int code, String name) {
         super();
         this.code = code;
         this.name = name;
     }

     @Override
     public String toString() {
         return "Course [code=" + code + ", name=" + name + "]";
     }
 }

 package com.lovo.day2;

 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.util.Date;

 public class ObjectTest {

     public static void main(String[] args) {
         Student stu = new Student("张飞", 18, true, 10.0, new Date(), new Course(
                 1, "语文"));
         Student stu2 = new Student("张飞2", 18, true, 10.0, new Date(), new Course(
                 2, "数学"));

         // 序列化
         ObjectOutputStream out = null;

         try {
             out = new ObjectOutputStream(
                     new FileOutputStream("d:\\student.bin"));
             out.writeObject(stu);
             out.writeObject(stu2);
         } catch (FileNotFoundException e) {
             e.printStackTrace();
         } catch (IOException e) {
             e.printStackTrace();
         } finally {
             if (out != null) {
                 try {
                     out.close();
                 } catch (IOException e) {
                     e.printStackTrace();
                 }
             }
         }

         // 反序列化
         ObjectInputStream in = null;

         try {
             in = new ObjectInputStream(new FileInputStream("d:\\student.bin"));
             Student stu1 = (Student) in.readObject();
             System.out.println(stu1);

             System.out.println("*****************");

             System.out.println(stu1.getCourse());

             System.out.println("#######################################");

             Student stu21 = (Student) in.readObject();
             System.out.println(stu21);

             System.out.println("*****************");

             System.out.println(stu21.getCourse());
         } catch (FileNotFoundException e) {
             e.printStackTrace();
         } catch (IOException e) {
             e.printStackTrace();
         } catch (ClassNotFoundException e) {
             e.printStackTrace();
         } finally {
             if (in != null) {
                 try {
                     in.close();
                 } catch (IOException e) {
                     e.printStackTrace();
                 }
             }
         }
     }
 }