抽象类概述
在JAVA中，一个没有方法体的方法应该定义为抽象方法，而类中如果有抽象方法，该类必须定义为抽象类
package itheima;
public class AnimalDemo {
public static void main(String[] args) {
// Animal a=new Animal() ;抽象类不是具体的不能创建对象
// a.eat();
}
}
package itheima;
public abstract class Animal {
//public void eat(){
// System.out.println("吃东西");
//}
//public void eat();没有方法体的方法必须加abstract
public abstract void eat();//抽象方法的类必须定义为抽象类
}
package itheima;
public class AnimalDemo {
public static void main(String[] args) {
Animal a=new Cat();
a.setName("加菲");
a.setAge(5);
System.out.println(a.getName()+","+a.getAge());
a.eat();
System.out.println("----------");
a=new Cat("加菲",5);
System.out.println(a.getName()+","+a.getAge());
a.eat();
}
}
package itheima;
public abstract class Animal {
private String name;
private int age;
public Animal(){
}
public Animal(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;
}
public abstract void eat();
}
package itheima;
public class Dog extends Animal{
public Dog() {
}
public Dog(String name, int age) {
super(name, age);
}
@Override
public void eat(){
System.out.println("狗吃骨头");
}
}
package itheima;
public class Cat extends Animal{
public Cat() {
}
public Cat(String name, int age) {
super(name, age);
}
@Override
public void eat(){
System.out.println("猫吃鱼");
}
}
