Java 静态工厂Demo

接口Car.java

/*
 * package factory;
 */
public interface Car {
    public abstract void start();
}

实现类Pickup.java

/*
 * package factory;
 */
public class Pickup implements Car {
    public void start() {
        System.out.println("Pickup start!");
    }
    
}

 实现类Mini.java

/*
 * package factory;
 */
public class Mini implements Car {
    @Override
    public void start() {
        System.out.println("Mini Car start!");
    }
}

工厂类CarFactory.java

/*
 * package factory;
 */
public class CarFactory {
    private static Car car = null;
    public static Car getCar(String type) {
        if ("Pickup".equalsIgnoreCase(type)) {
            car = new Pickup();
        }
        if ("Mini".equalsIgnoreCase(type)) {
            car = new Mini();
        }
        return car;
    }
}

属性文件cars.properties

Mini = factory.Mini
Pickup = factory.Pickup

使用属性文件的工厂类CarFactoryWithProperties.java

/*
 * package factory;
 */
public class CarFactoryWithProperties {
    private static Car car = null;
    public static Properties properties = new Properties();
    public static Car getCar(String type) throws IOException, InstantiationException, ClassNotFoundException, IllegalAccessException {
        InputStream inStream = null;
        inStream = new FileInputStream("src/factory/cars.properties");
        properties.load(inStream);
        String carClass = properties.getProperty(type);
        car = (Car) Class.forName(carClass).newInstance();
        return car;
    }
}

 

测试类Test.java

/*
 * package factory;
 */
public class Test {
    public static void main(String[] args) throws IOException, InstantiationException, ClassNotFoundException, IllegalAccessException {
        CarFactory.getCar("mini").start();
        CarFactory.getCar("Pickup").start();
        System.out.println("-----------------------------");
        CarFactoryWithProperties.getCar("Mini").start();
        //CarFactoryWithProperties.getCar("mini").start();
    }
}

 

运行结果：

run:
Mini Car start!
Pickup start!
-----------------------------
Mini Car start!
成功构建 (总时间: 0 秒)