Struts2 on action button HTTP Status 404 - There is no Action mapped for namespace / and action name add

I m Newbie to Struts2 and I am following http://viralpatel.net/blogs/2010/01/tutorial-struts2-hibernate-example-eclipse.html 开发者_StackOverflow中文版to make Struts2 project but i m getting error : HTTP Status 404 - There is no Action mapped for namespace / and action name add. I am creating project in "Netbeans 6.8". URL pattern on which I am getting error http://localhost:8080/StrutsTest/add

My Log :

WARNING: No configuration found for the specified action: 'add' in namespace: ''. Form action defaulting to 'action' attribute's literal value.
WARNING: No configuration found for the specified action: 'add' in namespace: ''. Form action defaulting to 'action' attribute's literal value.
WARNING: Could not find action or result
There is no Action mapped for namespace / and action name add. - [unknown location]
        at com.opensymphony.xwork2.DefaultActionProxy.prepare(DefaultActionProxy.java:178)
        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:478)
        at org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:395)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:277)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:188)
        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:641)
        at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:97)
        at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:85)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:185)
        at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:332)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:233)
        at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:165)
        at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:791)
        at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:693)
        at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:954)
        at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:170)
        at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:135)
        at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:102)
        at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:88)
        at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:76)
        at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:53)
        at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:57)
        at com.sun.grizzly.ContextTask.run(ContextTask.java:69)
        at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:330)
        at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:309)
        at java.lang.Thread.run(Thread.java:619)

For those of you still having troubles resolving the above error. This is what i did that worked for me. Within the jsp page that is rendering the form, on the form tag, i just included the namespace of the package that the referred form action name is located, for example:

struts.xml ( this is just a fraction of my struts.xml config )

<package name="user" namespace="/user" extends="struts-default">
    <action name="update" class="actionbean.UserProfileUpdate">
        <result name="error">pages/error.jsp</result>       
        <result name="success" type="redirect">pages/profile.jsp</result>
    </action>
</package>

NOTE: the action name is update and it's within /user namespace.

profile.jsp --> This form generates above error

this code generates above error ( when i used it ), solely because i didn't include the namespace attribute

<form action="update" method="post">
    .....
    [ other codes ]
</form>

profile.jsp --> (this form runs as expected)

<form action="update" method="post" namespace="/user">
    .....
    [ other codes ]
</form>

please note: i'm not sure why this solution worked for me, reason is because i have several forms in my web app as at the time i'm providing this information, and i didn't have to do this in any other form except this update form.

vital information about my environment if needed

Product Version: NetBeans IDE 8.2 (Build 201705191307)

Updates: NetBeans IDE is updated to version NetBeans 8.2 Patch 2

Java: 1.8.0_161; Java HotSpot(TM) 64-Bit Server VM 25.161-b12

Strut: strut 2 core 2.3.15

Good luck with this.

Please copy your struts.xml file it will help to understand.what i can find from your log is that wither you have done wrong configuration in the xml file or you have defined an action in xml which is not yet defined