JSTL Request scope bound List problem

[K Mansoor]

Folks- I'm stuck with a seemingly very simple problem.
I have a List<MyType> set to the Request from a servlet (actually to the Model in a Spring Controller).

List<MyList> myList = getMyListOfObjects();
model.addAttribute("myList", myList);

In the JSP/JSTL, I'm trying to create an HTML SELECT/OPTION like this:

<select 
	<c:if test="${myList.size} eq 1">
						disabled
					</c:if>					
>
	<c:forEach items="${myList}" var="myvar">
		<c:if test="${myList.size} > 1">
			<option>-- Please select --</option>
		</c:if>
		<option value='<c:out value="${myvar.id}"/>'><c:out value="${myvar.name}" /></option>
	</c:forEach>
</select>

This results in the following exception:

java.lang.NumberFormatException: For input string: "size"
	java.lang.NumberFormatException.forInputString(NumberFormatException.java:48)
	java.lang.Integer.parseInt(Integer.java:449)
	java.lang.Integer.parseInt(Integer.java:499)
	javax.el.ListELResolver.coerce(ListELResolver.java:174)
	javax.el.ListELResolver.getValue(ListELResolver.java:52)
	javax.el.CompositeELResolver.getValue(CompositeELResolver.java:67)
	org.apache.el.parser.AstValue.getValue(AstValue.java:169)
	org.apache.el.parser.AstDynamicExpression.getValue(AstDynamicExpression.java:44)
	org.apache.el.parser.AstCompositeExpression.getValue(AstCompositeExpression.java:50)
	org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:189)
	org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:985)
	org.apache.jsp.WEB_002dINF.jsp.home.home_jsp._jspx_meth_c_005fif_005f0(home_jsp.java:190)
	org.apache.jsp.WEB_002dINF.jsp.home.home_jsp._jspService(home_jsp.java:111)
	org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:417)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:391)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
	org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:927)
	org.apache.jasper.runtime.PageContextImpl.doInclude(PageContextImpl.java:684)
	org.apache.jasper.runtime.PageContextImpl.include(PageContextImpl.java:678)
	org.apache.tiles.jsp.context.JspTilesRequestContext.include(JspTilesRequestContext.java:103)
	org.apache.tiles.jsp.context.JspTilesRequestContext.dispatch(JspTilesRequestContext.java:96)
	org.apache.tiles.renderer.impl.TemplateAttributeRenderer.write(TemplateAttributeRenderer.java:44)
	org.apache.tiles.renderer.impl.AbstractBaseAttributeRenderer.render(AbstractBaseAttributeRenderer.java:106)
	org.apache.tiles.renderer.impl.ChainedDelegateAttributeRenderer.write(ChainedDelegateAttributeRenderer.java:76)
	org.apache.tiles.renderer.impl.AbstractBaseAttributeRenderer.render(AbstractBaseAttributeRenderer.java:106)
	org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:670)
	org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:336)
	org.apache.tiles.template.InsertAttributeModel.renderAttribute(InsertAttributeModel.java:210)
	org.apache.tiles.template.InsertAttributeModel.end(InsertAttributeModel.java:126)
	org.apache.tiles.jsp.taglib.InsertAttributeTag.doTag(InsertAttributeTag.java:311)
	org.apache.jsp.WEB_002dINF.jsp.layout_jsp._jspx_meth_tiles_005finsertAttribute_005f2(layout_jsp.java:242)
	org.apache.jsp.WEB_002dINF.jsp.layout_jsp._jspService(layout_jsp.java:105)
	org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:417)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:391)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
	org.apache.tiles.servlet.context.ServletTilesRequestContext.forward(ServletTilesRequestContext.java:241)
	org.apache.tiles.servlet.context.ServletTilesRequestContext.dispatch(ServletTilesRequestContext.java:222)
	org.apache.tiles.renderer.impl.TemplateAttributeRenderer.write(TemplateAttributeRenderer.java:44)
	org.apache.tiles.renderer.impl.AbstractBaseAttributeRenderer.render(AbstractBaseAttributeRenderer.java:106)
	org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:670)
	org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:690)
	org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:644)
	org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:627)
	org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:321)
	org.springframework.web.servlet.view.tiles2.TilesView.renderMergedOutputModel(TilesView.java:124)
	org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:250)
	org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1047)
	org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:817)
	org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
	org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
	org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
	org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
	org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:368)
	org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:109)
	org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
	org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
	org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:97)
	org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
	org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:100)
	org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
	org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:78)
	org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
	org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
	org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
	org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:35)
	org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
	org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilter(BasicAuthenticationFilter.java:177)
	org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
	org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:187)
	org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
	org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
	org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
	org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:79)
	org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
	org.springframework.security.web.access.channel.ChannelProcessingFilter.doFilter(ChannelProcessingFilter.java:109)
	org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
	org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:169)
	org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)
	org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)

I tried a variation; prepended 'param' to the request bound object:

<select 
	<c:if test="${param.myList.size} eq 1">
		disabled
	</c:if>					
>
	<c:forEach items="${myList}" var="myvar">
		<c:if test="${param.myList.size} > 1">
			<option>-- Please select --</option>
		</c:if>
		<option value='<c:out value="${myvar.id}"/>'><c:out value="${myvar.name}" /></option>
	</c:forEach>
</select>

The page is rendered (no exceptions) but neither the <SELECT> is 'disabled' if the list contains only 1 element
nor an <OPTION>--Please select--</OPTION> is added when the list contains more than 1 item. In other words the tests

	<c:if test="${param.myList.size} eq 1">
		disabled
	</c:if>					

	<c:if test="${param.myList.size} > 1">
		<option>-- Please select --</option>
	</c:if>

are never evaluated.

What am I missing? please help.

I tried == and > instead of 'eq' and 'gt' to no avail.
Thanks.

[Bear Bibeault]

I tried a variation; prepended 'param' to the request bound object:

Randomly trying stuff without understanding it hardly ever works. Just don't. Why would params do anything for you here?

There is no size property on lists. Look at the javadoc. Do you see a getSize() accessor on List? Nope. No accessor == no property.

To get the size of a collection in the EL, use the fn:length() JSTL function.

[K Mansoor]

As always, it worked! Thank you.

I guess the size() method on List threw me off, didn't realize size will be invoked as getSize.

Randomly trying stuff without understanding it hardly ever works. Just don't.

Bear- I say it with utmost respect, but it sounds like my Mom.

[Bear Bibeault]

And never argue with your mother!!!