public class Test {public static void main(String[] args) {// TODO Auto-generated method stub//实例化两个父类对象,并传入两组相同的参数值Car car1=new Car("蓝色","张小泉");Car car2=new Car("蓝色","张小泉");//调用父类use方法car1.use();car2.use();//测试重写equals 方法，判断两个对象是否相等System.out.println("car1和car2的引用比较:"+car1.equals(car2));System.out.println("======================");//实例化子类对象，并传入相关参数值Taxi taxi=new Taxi("蓝色","张小泉","长生公司");taxi.ride();taxi.use();//测试重写toString 方法,输出子类对象的信息System.out.println(taxi.toString());System.out.println("======================");HomeCar hc=new HomeCar("紫色","张二娘",7);hc.display();hc.display(5);}}

2.Car.java

public class Car {
private String color;
private String userName;
public Car() {}
public Car(String color,String userName) {this.setColor(color);this.setUserName(userName);
}
public String getColor() {return color;
}
public void setColor(String color) {this.color = color;
}
public String getUserName() {return userName;
}
public void setUserName(String userName) {this.userName = userName;
}
public void use() {System.out.println("我是机动车");
}
public boolean equals(String color,String userName)
{if(this.getColor()==null||this.getUserName()==null)return false;elsereturn true;
}
public boolean equals(Car car) {if(this.getColor()==car.getColor()||this.getUserName()==car.getUserName())return true;elsereturn false;
}
}

3.HomeCar.java

public final class HomeCar extends Car{
private int num;public HomeCar() {}
public HomeCar(String color,String userName,int num) {super(color,userName);this.setNum(num);
}public int getNum() {return num;
}public void setNum(int num) {this.num = num;
}
public void display() {System.out.println(this.getUserName()+"拥有的"+this.getColor()+"颜色的私家车有"+this.getNum()+"座位");
}
public void display(int num) {this.setNum(num);System.out.println("家用汽车大多有"+this.getNum()+"个座位");
}
}

4.Taxi.java

public class Taxi extends Car{private String company;public Taxi() {}//对所有参数进行赋值public Taxi(String color,String userName,String company) {super(color,userName);this.setCompany(company);}public String getCompany() {return company;}public void setCompany(String company) {this.company = company;}public final void ride() {System.out.println(this.getUserName()+"的出租车是所属于在"+this.getCompany());}public void use() {System.out.println("出租车是提高市民生活质量的重要条件之一");}public String toString() {return "taxi的信息是"+this.getUserName()+"拥有一辆"+this.getColor()+"的出租车";}
}

5.运行图片