承接上文

方法和事件

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.net篇（环境为vs2012+Spring.Core.dll v1.31）

    public abstract class MethodDemo

    {

        protected abstract SingleMethod CreateMethodByAbstract();

        public virtual SingleMethod CreateMethodByVireual() { return null; }

        public virtual String add(int x,int y){return x+y+"";}

        public virtual int add(int x, int y,int z) { return 0; }

        public SingleMethod Process1()

        {

            return this.CreateMethodByAbstract();

        }

    }

    public class MethodReplace :

        Spring.Objects.Factory.Support.IMethodReplacer

    {

        public object Implement(object target,

        System.Reflection.MethodInfo method, object[] arguments)

        {

            return "2";

        }

    }

    public delegate string Handler(String arg);

    public class HandlerDemo

    {

        public event Handler eventHandler;

        public void fire()

        {

            //调用事件

            if (eventHandler != null)

            {

                Console.WriteLine(eventHandler(null));

            }

        }

    }

    public class SingleMethod

    {

        public String Demo { get; set; }

        public string HandlerTigger(String arg)

        {

            return arg+"触发";

        }

    }

  <object id="single" type="SpringBase.SingleMethod, SpringBase" singleton="false">

    <property name="Demo" value="1"></property>

  </object>

  <object id="myObject" type="SpringBase.MethodDemo, SpringBase"

          depends-on="methReplace,hadlerDemo" >

    <lookup-method name="CreateMethodByAbstract" object="single"/>

    <lookup-method name="CreateMethodByVireual" object="single"/>

    <replaced-method name="add" replacer="methReplace">

      <arg-type match="Int"/>

      <arg-type match="Int"/>

    </replaced-method>

  </object>

  <object id="methReplace" type="SpringBase.MethodReplace, SpringBase"></object>

  <object id="hadlerDemo" type="SpringBase.HandlerDemo, SpringBase"></object>

下面是事件的触发

  IApplicationContext ctx = ContextRegistry.GetContext("test");

  HandlerDemo dao = (HandlerDemo)ctx.GetObject("hadlerDemo");

  ctx.PublishEvents(dao);

  SingleMethod single = (SingleMethod)ctx.GetObject("single");

  ctx.Subscribe(single);

  dao.fire();

1. lookup-method和replaced-method都必须是虚方法或者抽象方法
2. replaced-method的类必须继承Spring.Objects.Factory.Support.IMethodReplacer,
   实现Implement方法,替换方法返回int的时候会有问题
3. PublishEvents发布事件,Subscribe订阅事件

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java篇（环境为Maven+Jdk1.7+IntelliJ IDEA 12.1.4）

package springdemo;

import org.springframework.beans.factory.support.MethodReplacer;

import org.springframework.context.ApplicationEvent;

import org.springframework.context.ApplicationListener;

import java.lang.reflect.Method;

public abstract class MethodDemo {

    protected abstract SingleMethod CreateMethodByAbstract();

    public SingleMethod CreateMethodByVireual() {

        return null;

    }

    public Integer add(Integer x, Integer y) {

        return x + y;

    }

}

class SingleMethod {

    private String demo;

    public SingleMethod(String demo) {

        this.demo = demo;

    }

    public String getDemo() {

        return demo;

    }

    public void setDemo(String demo) {

        this.demo = demo;

    }

}

class MethodReplace implements MethodReplacer {

    @Override

    public Object reimplement(Object obj, Method method, Object[] args) throws Throwable {

        System.out.println("MethodReplace: true");

        return args.length;

    }

}

class EventHandler extends ApplicationEvent {

    public EventHandler(Object source) {

        super(source);

    }

}

class EventListener implements ApplicationListener {

    @Override

    public void onApplicationEvent(ApplicationEvent event) {

        if (event instanceof EventHandler) {

            EventHandler singleMethod = (EventHandler) event;

            System.out.println("DemoEvent: " + singleMethod.toString());

        }

    }

}

 <bean class="springdemo.EventListener"/>

    <bean id="singleMethod" class="springdemo.SingleMethod">

        <constructor-arg index="0" value="test"/>

    </bean>

    <bean id="methodReplace" class="springdemo.MethodReplace"/>

    <bean id="methodDemo" class="springdemo.MethodDemo">

        <lookup-method name="CreateMethodByAbstract" bean="singleMethod" />

        <lookup-method name="CreateMethodByVireual" bean="singleMethod" />

        <replaced-method name="add" replacer="methodReplace" />

  </bean>

下面是事件的触发

  ApplicationContext ctx = new FileSystemXmlApplicationContext("classpath:bean.xml");

  ctx.publishEvent(new EventHandler(ctx));

1. replaced-method的类必须继承MethodReplacer,实现reimplement方法
2. 事件监听必须继承ApplicationListener并且要在bean.xml文件里面配置,
   否则无效,不过id可以忽略,因为是所有的事件都会进所以
   最好instanceof判断下是不是自己要的事件,否则会报错,
3. 事件必须继承ApplicationEvent,构造函数的参数为发起者
4. 通过ctx.publishEvent(new EventHandler(ctx))来触发事件

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java和Csharp的共同点

1. lookup-method为实现方法,replaced-method为替换方法，并且方法不能包含任何参数
2. depends-on表示依赖那个对象用逗号分隔
3. replaced-method的类继承接口后的方法第一个参数为要替换的对象,第二个为替换的方法
   第三个为方法参数
4. replaced-method里面的arg-type是为了匹配参数类型重载的时候,
   当只有一个方法的时候可以忽略

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