Java中SerialVersionUID关键字的重要性？
SerialVersionUID
在Java中，SerialVersionUID必须声明为私有的静态最终长变量。此数字由编译器根据类的状态和类属性计算。当JVM从文件中读取对象的状态时，该数字将帮助JVM识别对象的状态
在反序列化期间可以使用SerialVersionUID来验证序列化对象的发送方和接收方是否为该对象加载了与w.r.t序列化兼容的类。如果反序列化对象与序列化不同，则它可以引发InvalidClassException。
如果未指定serialVersionUID， 则运行时将根据类的各个方面来计算该类的默认serialVersionUID值 。
示例
import java.io.*;
class Employee implements Serializable {
private static final long serialVersionUID = 5462223600l;
int empId;
String name;
String location;
Employee(int empId, String name, String location) {
this.empId = empId;
this.name = name;
this.location = location;
}
void empData() {
System.out.println("Employee Id is: "+ empId);
System.out.println("Employee Name is: "+ name);
System.out.println("Employee Location is: "+ location);
}
}
public class EmployeeTest {
public static void main(String[] args)throws Exception{
Employee emp = new Employee(115, "Raja", "Hyderabad");
emp.empData(); FileOutputStream fos = new FileOutputStream("E:\\Employee.txt");
ObjectOutputStream oos = new ObjectOutputStream(fos);
oos.writeObject(emp);
System.out.println("Object Serialized");
}
}输出结果
Employee Id is: 115 Employee Name is: Raja Employee Location is: Hyderabad Object Serialized