java--面向对象之抽象类

╰+哭是因爲堅強的太久メ 2022-06-03 01:16 435阅读 0赞

**案例一：**

**Vehicle:**

package Abstract;

public abstract class Vehicle \{  
//public abstract void numOfWheel();  
public abstract String numOfWheel();

**Car:**

package Abstract;  
  
  
public class Car extends Vehicle \{  
  
  
@Override  
public String numOfWheel() \{  
  
return "四轮车";  
\}  
  
  
/\*@Override  
public void numOfWheel() \{  
System.out.println("四轮车");  
  
  
\}\*/  
  
\}

**Motorbike:**

package Abstract;  
  
  
public class Motorbike extends Vehicle \{  
  
  
@Override  
public String numOfWheel() \{  
  
return "双轮车";  
\}  
  
  
/\*@Override  
public void numOfWheel() \{  
System.out.println("双轮车");  
  
  
\}\*/  
  
\}

**Test:**

package Abstract;  
  
  
import org.junit.Test;  
  
  
public class jTest \{  
@Test  
public void test()\{  
Car car=new Car();  
Motorbike mk=new Motorbike();  
/\*car.numOfWheel();  
mk.numOfWheel();\*/  
String name1=car.numOfWheel();  
System.out.println(name1);  
String name2=mk.numOfWheel();  
System.out.println(name2);  
\}  
\}

案例二：

Motovercal：

package Abstract2;  
  
  
public abstract class Motovercal \{  
/\*\*  
\* 抽象类  
\* 1.如果在程序设计过程中，定义了某个方法不需要该类来实现，  
\* 需要子类来重写，那么该方法应该定义为抽象方法，通过abstract关键字进行修饰  
\* 2.如果某各类中定义了抽象方法，那么该类务必定义为抽象类。  
\* 3.抽象方法只需要定义，不需要实现，谁继承，谁实现  
\*/  
private String id;  
private String type;  
private double price;  
  
public Motovercal(String id, String type, double price) \{  
this.id = id;  
this.type = type;  
this.price = price;  
\}  
  
  
public abstract void show();//定义抽象方法  
  
  
public String getId() \{  
return id;  
\}  
  
  
public void setId(String id) \{  
this.id = id;  
\}  
  
  
public String getType() \{  
return type;  
\}  
  
  
public void setType(String type) \{  
this.type = type;  
\}  
  
  
public double getPrice() \{  
return price;  
\}  
  
  
public void setPrice(double price) \{  
this.price = price;  
\}  
\}

**Car：**

package Abstract2;  
  
  
public class Car extends Motovercal \{  
private String color;  
  
  
public Car(String id, String type, double price, String color) \{  
super(id, type, price);  
this.color = color;  
\}  
  
  
  
  
@Override  
public void show() \{  
System.out.println("本车车牌号为："+super.getId()+"类型为："+super.getType()+"价格为："+super.getPrice()+"座位："+this.color);  
  
  
\}  
  
  
\}  
**Bus ：**

package Abstract2;  
  
  
public class Bus extends Motovercal \{  
  
private int seatCount;  
public Bus(String id, String type, double price,int seatCount) \{  
super(id, type, price);  
this.seatCount=seatCount;  
\}  
  
  
@Override  
public void show() \{  
System.out.println("本车车牌号为："+super.getId()+"类型为："+super.getType()+"价格为："+super.getPrice()+"座位："+this.seatCount);  
  
  
\}  
  
  
\}

**Test:**

package Abstract2;  
  
  
import org.junit.Test;  
  
  
  
  
public class jTest \{  
@Test  
public void test()\{  
Motovercal mk1=new Car("A00001", "jeep",450000,"yellow");  
Motovercal mk2=new Bus("B00002", "金龙", 350000, 30);  
mk1.show();  
mk2.show();  
\}  
\}

**案例三：**

**Pet：**

package Pet;  
  
  
public abstract class Pet \{  
private String name;  
private String health;  
private String love;  
  
public Pet(String name, String health, String love) \{  
this.name = name;  
this.health = health;  
this.love = love;  
\}  
  
  
  
public abstract void eat();  
  
  
  
  
public String getName() \{  
return name;  
\}  
  
  
  
  
public void setName(String name) \{  
this.name = name;  
\}  
  
  
  
  
public String getHealth() \{  
return health;  
\}  
  
  
  
  
public void setHealth(String health) \{  
this.health = health;  
\}  
  
  
  
  
public String getLove() \{  
return love;  
\}  
  
  
  
  
public void setLove(String love) \{  
this.love = love;  
\}  
\}

**Penguin：**

package Pet;  
  
  
public class Penguin extends Pet \{  
public String sex;  
  
public Penguin(String name, String health, String love, String sex) \{  
super(name, health, love);  
this.sex = sex;  
\}  
  
  
@Override  
public void eat() \{  
System.out.println("吃鱼!");  
  
  
\}  
  
  
\}

**Dog：**

package Pet;  
  
  
public class Dog extends Pet \{  
public String strain;  
  
public Dog(String name, String health, String love, String strain) \{  
super(name, health, love);  
this.strain = strain;  
\}  
  
  
@Override  
public void eat() \{  
System.out.println("啃骨头!");  
  
  
\}  
  
  
\}

**PatFactory：**

package Pet;  
  
  
public class PatFactory \{  
public void getPet(String pet)\{  
if("小花".equals(pet))\{  
System.out.print("小花的小狗");  
\}else if("QQ".equals(pet))\{  
System.out.print("QQ的企鹅");  
\}else\{  
System.out.println("输入错误");  
\}  
\}  
\}

**Test:**

package Pet;  
  
  
import org.junit.Test;  
  
  
  
  
public class Jtest \{  
@Test  
public void test()\{  
Dog dog=new Dog("小花", "健康值为100,", "亲密度为20,", "拉布拉多犬");  
PatFactory pf=new PatFactory();  
System.out.print("名叫：");  
pf.getPet("小花");  
System.out.print("是一只"+dog.strain);  
System.out.print(dog.getHealth()+dog.getLove()+"跑回来");  
dog.eat();  
  
Penguin pg=new Penguin("小花", "健康值为100,", "亲密度为20,", "拉布拉多犬");  
//PatFactory p=new PatFactory();  
System.out.print("名叫：");  
pf.getPet("QQ");  
System.out.print("是个"+pg.sex);  
System.out.print(dog.getHealth()+dog.getLove()+"跑回来");  
dog.eat();  
\}  
\}