Seam Problem: Could not set field value by reflection

java, seam

Solution

You want to add a converter to your pages.xml file. Like this:

<param name="customerId" 
      value="#{presenceHome.customerId}" 
converterId="javax.faces.Long" />

See the seampay example provided with seam for more details.

Problem

I'm having a problem with my Seam code and I can't seem to figure out what I'm doing wrong. It's doing my head in :) Here's an excerpt of the stack trace: ``` Caused by: java.lang.IllegalArgumentException: Can not set java.lang.Long field com.oobjects.sso.manager.home.PresenceHome.customerId to java.lang.String ``` I'm trying to get a parameter set on my URL passed into one of my beans. To do this, I've got the following set up in my pages.xml: ``` <page view-id="/customer/presences.xhtml"> <begin-conversation flush-mode="MANUAL" join="true" /> <param name="customerId" value="#{presenceHome.customerId}" /> <raise-event type="PresenceHome.init" /> <navigation> <rule if-outcome="persisted"> <end-conversation /> <redirect view-id="/customer/presences.xhtml" /> </rule> </navigation> </page> ``` My bean starts like this: ``` @Name("presenceHome") @Scope(ScopeType.CONVERSATION) public class PresenceHome extends EntityHome<Presence> implements Serializable { @In private CustomerDao customerDao; @In(required = false) private Long presenceId; @In(required = false) private Long customerId; private Customer customer; // Getters, setters and other methods follow. They return the correct types defined above } ``` Finally the link I use to link one one page to the next looks like this: ``` <s:link styleClass="#{selected == 'presences' ? 'selected' : ''}" view="/customer/presences.xhtml" title="Presences" propagation="none"> <f:param name="customerId" value="#{customerId}" /> Presences </s:link> ``` All this seems to work fine. When I hover over the link above in my page, I get a URL ending in something like "?customerId=123". So the parameter is being passed over and it's something that can be easily converted into a Long type. But for some reason, it's not. I've done similar things to this before in other projects and it's worked then. I just can't see what it isn't working now. If I remove the element from my page declaration, I get through to the page fine. So, does anyone have any thoughts?

Original source