java繼承練習（java 第四周）

主要代碼：

package bzu.aa;

public class Vehicle {
    private int capacity;
    public Vehicle() {
        this.capacity = 2;
        System.out.println("執行交通工具類的無參構造方法。");
    }
    public Vehicle(int capacity) {
        this.capacity = capacity;
        System.out.println("執行交通工具的有參構造方法。");
    }
    public int getCapacity() {
        return capacity;
    }
    public void setCapacity(int capacity) {
        this.capacity = capacity;
    }
    public void print(){
        System.out.println("載客人數爲："+this.capacity);
    }
}

package bzu.aa;

public class Car extends Vehicle{
    private int speed;

    public int getSpeed() {
        return speed;
    }
    public void setSpeed(int speed) {
        this.speed = speed;
    }
    public Car(){
        this.speed=0;
        System.out.println("執行汽車類的無參構造方法。");
    }
    public Car(int speed){
        super(22);
        this.speed=speed;
        System.out.println("執行汽車類的有參構造方法。");
    }
    public int speedup(int data){
        for(;data>0;data--){
        this.speed+=10;
        }
        return this.speed;
    }
    public int speeddown(int data){
        for(;data>0;data--){
        this.speed-=15;
        }
        return this.speed;
    }
    public void print (){
        System.out.println("速度："+this.speed+"載客量："+getCapacity());
    }
}

package bzu.bb;
import bzu.aa.Car;
public final class Bus  extends Car{
    private int capacity;
    public  Bus(){
        this.capacity=20;
        System.out.println("執行公交車類的無參構造方法。");
    }
    public Bus(int capacity){
        super(50);
        this.capacity=capacity;
        System.out.println("執行公交車類的有參構造方法。");       
    }
    public void print(){
        System.out.println("速度："+getSpeed()+"載客量"+capacity+"父類的載客量"+getCapacity());
    }
}

package bzu.bb;

import bzu.aa.Car;

public class Test {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Car car=new Car();
        car.speedup(5);
        car.print();
        car.speeddown(2);
        car.print();
        Bus bus=new Bus(20);
        bus.print();
    }

}

演示效果：