Bacis doubt input property in struts-config.xml

[Mark Henryson]

I am very confused on the input property in the action mapping of struts-config.xml.
Whether the input property in the action mapping is mandatory and what it's use?.

I am trying do the following:

	<action path="/prepareReg" 
			type="com.example.action.PrepareRegAction">
		<forward name="success" path="/reg.jsp"/>
		<forward name="ajax" path="/SelectDropDown.jsp"/>
	</action>


	<action path="/processReg" 
			name="registrationForm"
			type="com.example.action.ProcessRegAction" 
			scope="request"
			input="/reg.jsp"
			validate="true">
		<forward name="showWelcome" path="page.welcome" />
		<forward name="success" path="/success.jsp"/>
		<forward name="failure" path="/failure.jsp"/>
	</action>

....
<html:form>
			<p>
				Option values and labels populated from the same array:
			</p>
			<p>
				<html:select property="color1" size="1">
					<html:options name="fruits" />
				</html:select>
			</p>
		<input type="button" name="ClickAjax" value="ClickAjax" onclick="callAjax();"/>
		<input type="text" name="sample1" value="ClickAjax"/>
		<html:select styleId="textElement" property="sample">
		</html:select>
		</html:form>
	</body>
</html>

public class PrepareRegAction extends Action{
	public ActionForward execute(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
			RegistrationForm regForm = (RegistrationForm)form;			
			HttpSession session = request.getSession();
			
		/* An array */
	        String[] fruits =
	            {
	                "Strawberry",
	                "Apple",
	                "Orange",
	                "Pear",
	                "Mango",
	                "Banana",
	                "Pineapple" };
	        request.setAttribute("fruits", fruits);			
		return mapping.findForward("success");
	}
}

public ActionForward execute(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
			RegistrationForm regForm = (RegistrationForm)form;			
			HttpSession session = request.getSession();			
			
			return mapping.findForward("success");
	}

I am getting the following error:

javax.servlet.jsp.JspException: Cannot find bean under name fruits
	at org.apache.struts.taglib.html.OptionsTag.getIterator(OptionsTag.java:377)
	at org.apache.struts.taglib.html.OptionsTag.doEndTag(OptionsTag.java:246)
	at org.apache.jsp.reg_jsp._jspx_meth_html_005foptions_005f0(reg_jsp.java:733)
	at org.apache.jsp.reg_jsp._jspx_meth_html_005fselect_005f1(reg_jsp.java:700)
	at org.apache.jsp.reg_jsp._jspx_meth_html_005fform_005f0(reg_jsp.java:353)
	at org.apache.jsp.reg_jsp._jspService(reg_jsp.java:177)
	at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:373)
	at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:336)
	at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:654)
	at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:445)
	at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:379)
	at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:292)
	at org.apache.struts.action.RequestProcessor.doForward(RequestProcessor.java:1083)
	at org.apache.struts.tiles.TilesRequestProcessor.doForward(TilesRequestProcessor.java:295)
	at org.apache.struts.action.RequestProcessor.internalModuleRelativeForward(RequestProcessor.java:1027)
	at org.apache.struts.tiles.TilesRequestProcessor.internalModuleRelativeForward(TilesRequestProcessor.java:374)
	at org.apache.struts.action.RequestProcessor.processValidate(RequestProcessor.java:995)
	at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:198)
	at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
	at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:462)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at com.example.filters.RegFilters.doFilter(RegFilters.java:27)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
	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:230)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
	at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:179)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:524)
	at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:84)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
	at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:157)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:262)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:446)
	at java.lang.Thread.run(Unknown Source)
16:29:08,836 ERROR [[action]] Servlet.service() for servlet action threw exception
javax.servlet.jsp.JspException: Cannot find bean under name fruits
	at org.apache.struts.taglib.html.OptionsTag.getIterator(OptionsTag.java:377)
	at org.apache.struts.taglib.html.OptionsTag.doEndTag(OptionsTag.java:246)
	at org.apache.jsp.reg_jsp._jspx_meth_html_005foptions_005f0(reg_jsp.java:733)
	at org.apache.jsp.reg_jsp._jspx_meth_html_005fselect_005f1(reg_jsp.java:700)
	at org.apache.jsp.reg_jsp._jspx_meth_html_005fform_005f0(reg_jsp.java:353)
	at org.apache.jsp.reg_jsp._jspService(reg_jsp.java:177)
	at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:373)
	at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:336)
	at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:654)
	at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:445)
	at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:379)
	at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:292)
	at org.apache.struts.action.RequestProcessor.doForward(RequestProcessor.java:1083)
	at org.apache.struts.tiles.TilesRequestProcessor.doForward(TilesRequestProcessor.java:295)
	at org.apache.struts.action.RequestProcessor.internalModuleRelativeForward(RequestProcessor.java:1027)
	at org.apache.struts.tiles.TilesRequestProcessor.internalModuleRelativeForward(TilesRequestProcessor.java:374)
	at org.apache.struts.action.RequestProcessor.processValidate(RequestProcessor.java:995)
	at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:198)
	at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
	at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:462)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at com.example.filters.RegFilters.doFilter(RegFilters.java:27)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
	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:230)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
	at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:179)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:524)
	at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:84)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
	at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:157)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:262)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:446)

[David Newton]

The exception shown has nothing to do with the "input" attribute. The "input" attribute defines the page that has the form on it--if validation fails this would be the page you'd want to return to. I don't recall if it's mandatory or not, but it's handy.

You don't describe the circumstances under which you get the exception, so it's hard to help.