第一天 工厂模式之简单工厂模式
首先定义一个接口

public interface Car {public void drive();}

两个实现类

public class BMWCar implements Car{public void drive() {System.out.println("驾驶了一辆宝马汽车");}}

public class QQCar implements Car{public void drive() {System.out.println("驾驶了一辆QQ汽车");}}

一个静态工厂，因为是静态的方法，所以又简单工厂模式又称为静态工厂模式。

public class CarFactory {public static Car factory(String witch) throws BadCarException {if(witch.equalsIgnoreCase("QQCar")) {return new QQCar();} else if(witch.equalsIgnoreCase("BMWCar")) {return new BMWCar();} else {throw new BadCarException(witch);}}}

public class BadCarException extends Exception {public BadCarException(String msg) {super(msg);}}

测试类

public class Client {public static void main(String[] args) {try {Car bmwCar = CarFactory.factory("BMWCar");Car qqCar = CarFactory.factory("QQCar");bmwCar.drive();qqCar.drive();} catch (BadCarException e) {e.printStackTrace();}}}