Java类继承及多态的应用实例分析

原创 Dear 丶 2024-12-10 17:09 27阅读 0赞

在Java编程中，类的继承和多态是两个重要的概念。下面我会通过一个具体的例子来详细分析。

**案例：汽车修理厂**

1. **创建基类（Vehicle）**：
```java
public class Vehicle {
    private String brand;
    private int year;

// 构造函数、getter和setter方法
}
```
2. **创建子类（Car）**，继承`Vehicle`并添加特定属性：
```java
public class Car extends Vehicle {
    private String color;
    private double price;

// 构造函数、getter和setter方法

public Car(String brand, int year, String color, double price) {
        super(brand, year);
        this.color = color;
        this.price = price;
    }
}
```
3. **创建另一个子类（SUV）**，继承`Car`并添加特定属性：
```java
public class SUV extends Car {
    private boolean fourWheels;

// 构造函数、getter和setter方法

public SUV(String brand, int year, String color, double price, boolean fourWheels) {
        super(brand, year, color, price);
        this.fourWheels = fourWheels;
    }
}
```
4. **示例使用**：创建不同类型的车辆对象并进行操作：
```java
public class Main {
    public static void main(String[] args) {
        // 创建Car和SUV对象
        Car myCar = new Car("Toyota", 2023, "Blue", 25000);
        SUV mySUV = new SUV("Ford", 2024, "Gray", 35000, true);

// 展示对象的属性
        System.out.println("My Car:");
        System.out.println("Brand: " + myCar.getBrand());
        System.out.println("Year: " + myCar.getYear());
        System.out.println("Color: " + myCar.getColor());
        System.out.println("Price: " + myCar.getPrice());

System.out.println("\nMy SUV:");
        System.out.println("Brand: " + mySUV.getBrand());
        System.out.println("Year: " + mySUV.getYear());
        System.out.println("Color: " + mySUV.getColor());
        System.out.println("Price: " + mySUV.getPrice());
        System.out.println("FourWheels: " + mySUV.isFourWheels()));

// 根据价格排序
        List<Car> cars = new ArrayList<>();
        cars.add(myCar);
        cars.add(mySUV);

Collections.sort(cars, (car1, car2) -> car2.getPrice() - car1.getPrice()));

System.out.println("\nCars sorted by price:");
        for (Car car : cars) {
            System.out.println(car + " - Price: " + car.getPrice()));
        }
    }
}
```
这个例子展示了如何在Java中使用类的继承和多态。同时，我们也看到了如何根据对象的属性进行排序。