sampleFactory

public interface Animal { /**所有动物都会吃*/  public void eat(); } public class Tiger implements Animal {  public void eat() {   System.out.println("老虎要吃饭！");  }  public void run() {   System.out.println("老虎要跑步！");  } } public class Parrot implements Animal {  public void eat() {   // TODO Auto-generated method stub   System.out.println("鹦鹉要吃饭");  }  public void fly() {   System.out.println("鹦鹉要飞翔");  } } public class sampleFactory {  public static int i = 0;  public static Animal createAnimal(String animalName)    throws ClassNotFoundException, InstantiationException,    IllegalAccessException {   i++;   System.out.println(i);   Class c = Class.forName(animalName);   Animal animal = (Animal) c.newInstance();   return animal;  } } public class Client {  /**   * @param args   * @throws IllegalAccessException   * @throws InstantiationException   * @throws ClassNotFoundException   */  public static void main(String[] args) throws ClassNotFoundException,    InstantiationException, IllegalAccessException {   // TODO Auto-generated method stub   Animal animal = sampleFactory.createAnimal("Tiger");   animal.eat();   Tiger tiger = (Tiger) animal;   tiger.run();   animal = sampleFactory.createAnimal("Dolphin");   animal.eat();   animal = sampleFactory.createAnimal("Parrot");   animal.eat();  } }   优点：客户端不再负责对象创建， 把这个责任丢给了具体的工厂类 缺点：1、由于简单工厂使用静态方法创建对象，导致静态方法无法被继承；2、当具体产品增多时候，客户端需要不同的方式创建具体产品，需要不断修改工厂类；