Java编程中的标记接口。
Java中的空接口称为标记接口，即，通过实现这些接口，它不包含任何方法或字段，一类相对于所实现的接口将表现出特殊的行为。java.lang.Cloneable和java.io.Serializable是标记接口的示例。
例1
请看以下示例，这里我们有一个名为Student的类，该类实现了标记接口Cloneable。在main方法中，我们尝试创建Student类的对象，并使用clone()方法对其进行克隆。
import java.util.Scanner;
public class Student implements Cloneable {
int age;
String name;
public Student (String name, int age){
this.age = age;
this.name = name;
}
public void display() {
System.out.println("Name of the student is: "+name);
System.out.println("Age of the student is: "+age);
}
public static void main (String args[]) throws CloneNotSupportedException {
Scanner sc = new Scanner(System.in);
System.out.println("Enter your name: ");
String name = sc.next();
System.out.println("Enter your age: ");
int age = sc.nextInt();
Student obj = new Student(name, age);
Student obj2 = (Student) obj.clone();
obj2.display();
}
}输出结果
Enter your name: Krishna Enter your age: 29 Name of the student is: Krishna Age of the student is: 29
例2
在下面的Java程序中，Student类具有两个实例变量name和age，其中age被声明为瞬态。在另一个名为ExampleSerialize的类中，我们尝试对Student对象进行序列化和反灭菌，并显示其实例变量。由于年龄是不可见的（短暂的），因此仅显示名称值。
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
class Student implements Serializable{
private String name;
private transient int age;
public Student(String name, int age){
this.name = name;
this.age = age;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
public void setAge(int age) {
this.age = age;
}
public int getAge() {
return this.age;
}
}
public class ExampleSerialize {
public static void main(String args[]) throws Exception{
Student std1 = new Student("Krishna", 30);
FileOutputStream fos = new FileOutputStream("e:\\student.ser");
ObjectOutputStream oos = new ObjectOutputStream(fos);
oos.writeObject(std1);
FileInputStream fis = new FileInputStream("e:\\student.ser");
ObjectInputStream ois = new ObjectInputStream(fis);
Student std2 = (Student) ois.readObject();
System.out.println(std2.getName());
}
}输出结果
Krishna