Struts dispatcher cannot be found

Struts dispatcher cannot be found

If you you see below exception Struts dispatcher cannot be found while running struts application:

HTTP Status 500 - The Struts dispatcher cannot be found. This is usually caused by using Struts tags without the associated filter. Struts tags are only usable when the request has passed through its servlet filter, which initializes the Struts dispatcher needed for this tag. - [unknown location]

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type Exception report

message The Struts dispatcher cannot be found. This is usually caused by using Struts tags without the associated filter. Struts tags are only usable when the request has passed through its servlet filter, which initializes the Struts dispatcher needed for this tag. - [unknown location]

description The server encountered an internal error that prevented it from fulfilling this request.

exception 

org.apache.jasper.JasperException: The Struts dispatcher cannot be found.  This is usually caused by using Struts tags without the associated filter. Struts tags are only usable when the request has passed through its servlet filter, which initializes the Struts dispatcher needed for this tag. - [unknown location]
	org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:549)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:470)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)


root cause 

The Struts dispatcher cannot be found.  This is usually caused by using Struts tags without the associated filter. Struts tags are only usable when the request has passed through its servlet filter, which initializes the Struts dispatcher needed for this tag. - [unknown location]
	org.apache.struts2.views.jsp.TagUtils.getStack(TagUtils.java:60)
	org.apache.struts2.views.jsp.StrutsBodyTagSupport.getStack(StrutsBodyTagSupport.java:44)
	org.apache.struts2.views.jsp.ComponentTagSupport.doStartTag(ComponentTagSupport.java:48)
	org.apache.jsp.index_jsp._jspx_meth_s_005fhead_005f0(index_jsp.java:130)
	org.apache.jsp.index_jsp._jspService(index_jsp.java:91)
	org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

Solution: Please check your web.xml file if you have added struts filter or not. Below shows struts 2 filter web.xml sample:

<!DOCTYPE web-app PUBLIC
 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
 "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
	<display-name>Archetype Created Web Application</display-name>

	<filter>
		<filter-name>struts2</filter-name>
		<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
		<init-param>
			<param-name>struts.devMode</param-name>
			<param-value>true</param-value>
		</init-param>
		<init-param>
            <param-name>struts.custom.i18n.resources</param-name>
            <param-value>ApplicationResources</param-value>
        </init-param>				
	</filter>

	<filter-mapping>
		<filter-name>struts2</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>
	
</web-app>

For more information about filter please refer this struts 2  site link here