SSH： Could not find action or result,There is no Action mapped for namespace /

警告: Could not find action or result  
There is no Action mapped for namespace / and action name hello_struts. - [unknown location]  
 at com.opensymphony.xwork2.DefaultActionProxy.prepare(DefaultActionProxy.java:177)  
 at org.apache.struts2.impl.StrutsActionProxy.prepare(StrutsActionProxy.java:61)  
 at org.apache.struts2.impl.StrutsActionProxyFactory.createActionProxy(StrutsActionProxyFactory.java:39)  
 at com.opensymphony.xwork2.DefaultActionProxyFactory.createActionProxy(DefaultActionProxyFactory.java:47)  
 at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:458)  
 at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)  
 at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:76)  
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)  
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)  
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)  
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)  
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)  
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)  
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)  
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)  
 at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)  
 at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)  
 at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)  
 at java.lang.Thread.run(Thread.java:619)  

使用SSH框架的時候，可能遇到這樣的問題，看到別人修改dev模式，其實不然，是因爲，你的目錄下沒有網頁，新建一個jsp頁面，就OK了