java对象序列化流和反序列化流
首先创建一个学生类
`import java.io.Serializable;
public class Student implements Serializable {
private static final long serialVersionUID = 42L;
private String name;
//private int age;
private transient int age;
public Student() {
}
public Student(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 "Student{" +
// "name='" + name + ''' +
// ", age=" + age +
// '}';
// }
}`
然后创建一个序列化流和反序列化流
1、用对象序列化流序列化了一个对象后,假如我们修改了对象所属的类文件,读取数据会不会出问题呢?
java.io.InvalidClassException:
当序列化运行时检测到类中的以下问题之一时抛出。
类的串行版本与从流中读取的类描述符的类型不匹配
该类包含未知的数据类型
该类没有可访问的无参数构造函数
com.itheima_03.Student; local class incompatible:
stream classdesc serialVersionUID = -3743788623620386195,
local class serialVersionUID = -247282590948908173
2、如果出问题了,如何解决呢?
给对象所属的类加一个值:private static final long serialVersionUID = 42L;
3、如果一个对象中的某个成员变量的值不想被序列化,又该如何实现呢?
private transient int age;
`
import java.io.*;
/*
*/
public class ObjectStreamDemo {
public static void main(String[] args) throws IOException, ClassNotFoundException {
//write();
read();
}
//反序列化
private static void read() throws IOException, ClassNotFoundException {
ObjectInputStream ois = new ObjectInputStream(new FileInputStream("oos.txt"));
Object obj = ois.readObject();
Student s = (Student) obj;
System.out.println(s.getName() + "," + s.getAge());
}
//序列化
private static void write()throws IOException {
ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("oos.txt"));
Student s = new Student("林青霞",30);
oos.writeObject(s);
oos.close();
}
}
`