Mule学习笔记（二）

mule的第一个应用非常简单。却也可以看出mule的运行机制。上例中，实现的是hello world 的例子，过程为：用户输入内容，回车，然后显示hello，[输入的内容]。这个实现非常简单，但是，却也存在一些问题，mule是怎么知道显示这些内容的，现在就研究这个。

也许大家觉得，在xxxx.xml中已经配置了类路径，mule当然可以找到这个类，问题就在这里，mule找到了实现类，那他是如何找到对应的方法的呢？ok，做一下尝试

将inteface修改为：

package demo.mule.umo;

public interface helloworld {

public string sayhello(string str);

public string sayhello();

}

package demo.mule.umo;

public interface helloworld {

public string sayhello(string str);

public string sayhello();

}

实现类修改为：

package demo.mule.umo.impl;

import demo.mule.umo.helloworld;

public class helloworldimpl

implements helloworld {

@override

public string sayhello(string str) {

return "hello," + str;

}

public string sayhello() {

return "hello world";

package demo.mule.umo.impl;

import demo.mule.umo.helloworld;

public class helloworldimpl implements helloworld {

@override

public string sayhello(string str) {

return "hello," + str;

public string sayhello() {

return "hello world";

运行项目：运行成功！

修改interface为：

public string sayhello2(string str);

修改实现类为：

public string sayhello2(string str) {

return "hello2 ," + str;

public string sayhello2(string str) {

return "hello2 ," + str;

运行：抛出error

error 2011-02-09

17:04:41,874 [helloumo.2] org.mule.service.defaultserviceexceptionstrategy:

********************************************************************************

message : [

the required property "method" is not set on the event

callableentrypointresolver:object "demo.mule.umo.impl.helloworldimpl@12f1bf0" does not implement required

interface "interface org.mule.api.lifecycle.callable"

found too many possible methods on object "demo.mule.umo.impl.helloworldimpl" that accept parameters

"{class java.lang.string}" using resolver

"reflectionentrypointresolver{ignoredmethods=[getclass, clone, equals, hashcode, getinvocationhandler, get*, wait, is*, notify, tostring, notifyall]{transformfirst=true, acceptvoidmethods=false}"

found too many possible methods on object

"demo.mule.umo.impl.helloworldimpl" that accept parameters "{class java.lang.string}" using resolver

"reflectionentrypointresolver{ignoredmethods=[getclass, clone, equals, hashcode, getinvocationhandler, get*, wait, is*, notify, tostring, notifyall]{transformfirst=false, acceptvoidmethods=false}"

]

type : org.mule.model.resolvers.entrypointnotfoundexception

code : mule_error--2

javadoc : http://www.mulesource.org/docs/site/current2/apidocs/org/mule/model/resolvers/entrypointnotfoundexception.html

exception stack is:

1. [

] (org.mule.model.resolvers.entrypointnotfoundexception)

org.mule.model.resolvers.defaultentrypointresolverset:63 (http://www.mulesource.org/docs/site/current2/apidocs/org/mule/model/resolvers/entrypointnotfoundexception.html)

root exception stack trace:

org.mule.model.resolvers.entrypointnotfoundexception: [

at org.mule.model.resolvers.defaultentrypointresolverset.invoke(defaultentrypointresolverset.java:63)

at org.mule.component.defaultlifecycleadapter.invoke(defaultlifecycleadapter.java:205)

at org.mule.component.abstractjavacomponent.invokecomponentinstance(abstractjavacomponent.java:83)

at org.mule.component.abstractjavacomponent.doinvoke(abstractjavacomponent.java:74)

at org.mule.component.abstractcomponent.invokeinternal(abstractcomponent.java:133)

at org.mule.component.abstractcomponent.invoke(abstractcomponent.java:161)

at org.mule.service.abstractservice.invokecomponent(abstractservice.java:929)

at org.mule.model.seda.sedaservice.access$100(sedaservice.java:56)

at org.mule.model.seda.sedaservice$componentstageworker.run(sedaservice.java:574)

at org.mule.work.workercontext.run(workercontext.java:310)

at edu.emory.mathcs.backport.java.util.concurrent.threadpoolexecutor.runworker(threadpoolexecutor.java:1061)

at edu.emory.mathcs.backport.java.util.concurrent.threadpoolexecutor$worker.run(threadpoolexecutor.java:575)

at java.lang.thread.run(thread.java:619)

error 2011-02-09 17:04:41,874 [helloumo.2] org.mule.service.defaultserviceexceptionstrategy:

********************************************************************************

message : [

the required property "method" is not set on the event

callableentrypointresolver:object "demo.mule.umo.impl.helloworldimpl@12f1bf0" does not implement required interface "interface org.mule.api.lifecycle.callable"

found too many possible methods on object "demo.mule.umo.impl.helloworldimpl" that accept parameters "{class java.lang.string}" using resolver "reflectionentrypointresolver{ignoredmethods=[getclass, clone, equals, hashcode, getinvocationhandler, get*, wait, is*, notify, tostring, notifyall]{transformfirst=true, acceptvoidmethods=false}"