Android编程设计模式之工厂方法模式实例详解

public abstract class Product {
  /**
   * 产品类的抽象方法
   * 由具体的产品类去实现
   * */
  public abstract void method();
}

public class ConcreteProductA extends Product {
  @Override
  public void method() {
    System.out.println("我是具体的产品A");
  }
}

public class ConcreteProductB extends Product {
  @Override
  public void method() {
    System.out.println("我是具体的产品B");
  }
}

public abstract class Factory {
  /**
   * 抽象工厂方法
   * 具体由子类实现
   * 
   * @return 具体的产品对象
   * */
  public abstract Product createProduct();
}

public class ConcreteFactory extends Factory {
  /**
   * 具体工厂类
   * */
  @Override
  public Product createProduct() {
    return new ConcreteProductA();
  }
}

public class Client {
  public static void main(String[] args) {
    Factory factory = new ConcreteFactory();
    Product product = factory.createProduct();
    product.method();
  }
}

我是具体的产品A

public class ConcreteFactory extends Factory {
  /**
   * 具体工厂类
   * */
  @Override
  public Product createProduct() {
    //return new ConcreteProductA();
    return new ConcreteProductB();
  }
}

public abstract class Factory {
  /**
   * 抽象工厂方法
   * 具体由子类实现
   * 
   * @param clz 产品对象类类型
   * 
   * @return 具体的产品对象
   * */
  public abstract <T extends Product> T createProduct(Class<T> clz);
}

public class ConcreteFactory extends Factory {
  /**
   * 具体工厂类
   * */
  @SuppressWarnings("unchecked")
  @Override
  public <T extends Product> T createProduct(Class<T> clz) {
    Product product = null;
    try {
      product = (Product) Class.forName(clz.getName()).newInstance();
    } catch (Exception e) {
      e.printStackTrace();
    }
    return (T)product;
  }
}

public class Client {
  public static void main(String[] args) {
    Factory factory = new ConcreteFactory();
    Product product = factory.createProduct(ConcreteProductB.class);
    product.method();
  }
}

public class ConcreteFactoryA extends Factory {
  /**
   * 具体工厂类
   **/
  @Override
  public Product createProduct() {
    return new ConcreteProductA();
  }
}
public class ConcreteFactoryB extends Factory {
  /**
   * 具体工厂类
   **/
  @Override
  public Product createProduct() {
    return new ConcreteProductB();
  }
}
public class Client {
  public static void main(String[] args) {
    Factory factoryA = new ConcreteFactoryA();
    Product productA = factoryA.createProduct();
    productA.method();
    Factory factoryB = new ConcreteFactoryB();
    Product productB = factoryB.createProduct();
    productB.method();
  }
}

public class Factory {
  /**
   * 具体工厂类
   **/
  @Override
  public static Product createProduct() {
    return new ConcreteProductA();
  }
}