继承

在java中表示继承关系的关键字是:extends关键字;

其语法形式如下:

public class B extends A{
}例如:
package com.example;

public class Animal {
public void eat(){
System.out.println("Animal can eat foot!");
}
public void move(){
System.out.println("Animal can move");
}
}
package com.example;

public class Lion extends Animal {

public void Prey(){
System.out.println("lion can prey!");
}
public void run(){
System.out.println("lion can run!");
}
public static void main(String[] args) {
Lion lion = new Lion();
lion.eat(); //Animal class member function
lion.move();
lion.Prey(); //Lion class member function
lion.run();
}
}
result is:
Animal can eat foot!

Animal can move

lion can prey!

lion can run!

在java中子类还可以用super关键字来调用父类的属性

例如:

package com.example;

public class Lion extends Animal {

public void Prey(){
super.eat(); //Call animal function with super
}
public void run(){
System.out.println("lion can run!");
}
public static void main(String[] args) {
Lion lion = new Lion();
lion.eat(); //Animal class member function
lion.move();
lion.Prey(); //Lion class member function
lion.run();
}
}
result is:
Animal can eat foot!

Animal can move

Animal can eat foot!

lion can run!

在java中表示常量的关键字是:final关键字;