设计模式之-工厂方法-FactoryMethod
定义一个用于创建对象的接口，让子类决定实例化哪一个类。FactoryMethod使一个类的实例化延迟到其子类。
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适用性:
1.当一个类不知道它所必须创建的对象的类的时候。
2.当一个类希望由它的子类来指定它所创建的对象的时候。
3.当类将创建对象的职责委托给多个帮助子类中的某一个，并且你希望将哪一个帮助子类是代理者这一信息局部化的时候。
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package pack.java.iworkfactory;public interface IWork {/** * 开始工作方法; */public void doWork();}?
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package pack.java.iworkfactory;public interface IWorkFactory {/** * 获取工作； * @return */public IWork getWork();}?
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package pack.java.workfactoryimpl;import pack.java.iworkfactory.IWork;import pack.java.iworkfactory.IWorkFactory;public class StudentFactory implements IWorkFactory{public IWork getWork() {// TODO Auto-generated method stubreturn new StudentWork();}}?
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package pack.java.workfactoryimpl;import pack.java.iworkfactory.IWork;public class StudentWork implements IWork {public void doWork() {// TODO Auto-generated method stubSystem.out.println("学生做作业!");}}?
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package pack.java.workfactoryimpl;import pack.java.iworkfactory.IWork;import pack.java.iworkfactory.IWorkFactory;public class TeacherFactory implements IWorkFactory{public IWork getWork() {// TODO Auto-generated method stubreturn new TeacherWork();}}?
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package pack.java.workfactoryimpl;import pack.java.iworkfactory.IWork;public class TeacherWork implements IWork {public void doWork() {// TODO Auto-generated method stubSystem.out.println("老师批改作业!");}}?
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package pack.java.testfactorymethod;import pack.java.iworkfactory.IWorkFactory;import pack.java.workfactoryimpl.StudentFactory;import pack.java.workfactoryimpl.TeacherFactory;public class TestFactoryMethod {/** * @param args */public static void main(String[] args) {// TODO Auto-generated method stub//学生工厂方法;IWorkFactory studentFactory = new StudentFactory();//学生开始工作;studentFactory.getWork().doWork();//老师工厂方法;IWorkFactory teacherFactory = new TeacherFactory();//老师开始工作;teacherFactory.getWork().doWork();}}?
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运行结果：
学生做作业!
老师批改作业!