serialVersionUID&transient的使用

package com.czie.iot1913.lps.IO.ObjectStream;

import java.io.*;

/**
 * FileName: ObjectStream
 * Author:   lps
 * Date:     2022/3/28 17:45
 * Sign:刘品水 Q：1944900433
 * InvalidClassException
 * 当序列化运行时检测到一个类中的下列问题之一时抛出。
 * 类的串行版本与从流中读取的类的不匹配
 * 该类包含未知的数据类型
 * 班上没有一个可访问的无参数构造函数
 *
 * 给对象所处的类加个值 private static final long serialVersionUID = 42L;
 * 
 * 
 * private transient int age;
 *
 */
public class ObjectStreamDemo {
    public static void main(String[] args) throws Exception {
        //write();
        read();
    }
    public static void write() throws Exception{
        //ObjectOutputStream(OutputStream out)
        //创建一个对象写入到指定的输出流。
        ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("F:\\JavaCode\\oos.txt"));
        Student s1 = new Student("刘品水",21);
        Student s2 = new Student();
        //void writeObject(Object obj)
        //写入指定的对象的对象。
        oos.writeObject(s1);
        //NotSerializableException
        // 当一个实例需要实现Serializable接口。序列化运行时或实例类可以抛出此异常。参数应该是类的名称。
        //一个类的串行化是由类实现java.io.serializable接口启用。类没有实现这个接口不会有任何序列化或反序列化其状态

        oos.close();

    }

    public static void read() throws IOException, ClassNotFoundException {
        ObjectInputStream ois = new ObjectInputStream(new FileInputStream("F:\\JavaCode\\oos.txt"));
        Object obj = ois.readObject();
        Student s = (Student) obj;
        //System.out.println(s);
        System.out.println(s.getName()+","+s.getAge());
        ois.close();
    }
}

package com.czie.iot1913.lps.IO.ObjectStream;

import java.io.Serializable;

/**
 * FileName: Student
 * Author:   lps
 * Date:     2022/3/28 15:12
 * Sign:刘品水 Q：1944900433
 */
public class Student implements Serializable {
 private static final long serialVersionUID = 42L;


 private String name;
// private int age;
private transient int age;


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

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

 public Student() {
 }
}