I'm trying to set up an editable dataTable along the same lines as the example in richfaces demo. I am using a seam generated project so my backing beans are extensions of EntityHome (hope I'm saying this correctly).

I have a datatable that contains 2 one-to-one entities, Devices and DevTags. I want to be able to edit the DevTag in a modalPanel component.

<rich:dataTable id="dataTable"
 value="#{officeViewHome.instance.devices}" var="_devices"
 rowKeyVar="rowId" ajaxKeys="#{devTagsHome.rowsToUpdate}">
 <rich:column>
 <f:facet name="header">Row ID</f:facet>
 <h:outputText value="#{rowId}" id="rowid" />
 </rich:column>
 <rich:column>
 <f:facet name="header">
 <h:outputText value="Hostname" />
 </f:facet>
 <h:outputText value="#{_devices.devName}" id="hostname" />
 </rich:column>
 <rich:column>
 <f:facet name="header">
 <h:outputText value="Platform" />
 </f:facet>
 <h:outputText value="#{_devices.devPlatform}" id="platform" />
 </rich:column>
 <rich:column>
 <f:facet name="header">
 <h:outputText value="Soft Serial Number" />
 </f:facet>
 <h:outputText value="#{_devices.devSerialNum}"
 id="softSerialNum" />
 </rich:column>
 <rich:column>
 <f:facet name="header">
 <h:outputText value="DEvID" />
 </f:facet>
 <h:outputText value="#{_devices.devId}" id="devId" />
 </rich:column>
 <rich:column>
 <f:facet name="header">
 <h:outputText value="Asset Tag" />
 </f:facet>
 <h:outputText value="#{_devices.devTag.devTagId}" />
 </rich:column>
 <rich:column>
 <f:facet name="header">
 <h:outputText value="Hard Serial Tag" />
 </f:facet>
 <h:outputText value="#{_devices.devTag.devSerialNum}" />
 </rich:column>

 <rich:column>
 <f:facet name="header">Action</f:facet>

 <a4j:commandLink id="editLink"
 onclick="#{rich:component('editPanel')}.show()"
 reRender="assetTagPanel">
 <h:graphicImage value="/img/icons/edit.gif" style="border:0" />
 <f:setPropertyActionListener value="#{_devices.devId}" target="#{devTagsHome.devTagsDevId}" />
 <f:setPropertyActionListener value="#{rowId}" target="#{devTagsHome.currentRow}" />
 </a4j:commandLink>
 <rich:toolTip for="editLink" value="Edit Tag"
 rendered="#{not empty _devices.devTag.tagId}" />
 <rich:toolTip for="editLink" value="New Tag"
 rendered="#{empty _devices.devTag.tagId}" />
 </rich:column>

 </rich:dataTable>

 <rich:modalPanel id="editPanel" autosized="true" width="450">
 <f:facet name="header">Asset Tag</f:facet>
 <f:facet name="controls">
 <h:panelGroup>
 <h:graphicImage value="/img/modal/close.png"
 id="hideEditPanel" styleClass="hidelink"
 onclick="#{rich:component('editPanel')}.hide()" />
 </h:panelGroup>
 </f:facet>
 <h:form>
 <rich:messages for="assetTagPanel" style="color:red;"></rich:messages>
 <a4j:outputPanel ajaxRendered="true" id="assetTagPanel">

 <h:panelGrid columns="2">
 <h:outputText value="Serial Number. Change if necessary" />
 <h:outputText value="#{devTagsHome.instance.devSerialNum}"
 rendered="#{not empty devTagsHome.instance.devSerialNum}" />
 <h:outputText value="Asset Tag" />
 <h:inputText value="#{devTagsHome.instance.devTagId}" />
 <h:outputText value="Comment" />
 <h:outputText value="#{devTagsHome.instance.comment}" />
 <h:outputText value="Single Site Code" />
 <h:outputText value="#{officeViewHome.officeViewSiteCode}" />
 </h:panelGrid>
 </a4j:outputPanel>
 <a4j:commandButton value="Persist"
 actionListener="#{devTagsHome.persist}"
 oncomplete="#{rich:component('editPanel')}.hide()"
 reRender="dataTable" />
 <a4j:commandButton value="Update"
 actionListener="#{devTagsHome.update}"
 oncomplete="#{rich:component('editPanel')}.hide()"
 reRender="dataTable" />
 </h:form>
 </rich:modalPanel>

The only field I need to edit is devTagId and then I want to save my change by clicking on Update. The result is a nullPointerException and when I run in the debugger and stop on the "update()" method, sure enough DevTagsHome is empty so of course it cannot be updated.


The data populates the modalPanel just fine so I know the devTags.instance is being found correctly. Why, when I get to devTags.update() does my app act like it has never seen this devTag before?

Here is DevTagsHome.java

@Name("devTagsHome")
public class DevTagsHome extends EntityHome<DevTags> {

 private Integer devTagsDevId;
 private Set<Integer> rowsToUpdate;
 private Integer currentRow;

 // Use devId to find the instance rather than tagId
 @Override
 public Object getId() {

 if (devTagsDevId == null) {
 return (Integer) super.getId();
 }
 return (Integer) getEntityManager().createQuery("select d.tagId from DevTags d " +
 "where d.devId=:devId ").setParameter("devId", devTagsDevId).
 getSingleResult();

 }


 protected DevTags createInstance() {
 DevTags devTags = new DevTags();
 return devTags;
 }

 public void load() {
 if (isIdDefined()) {
 wire();
 }
 }

 public void wire() {
 getInstance();
 }

 public boolean isWired() {
 return true;
 }

 public DevTags getDefinedInstance() {
 return isIdDefined() ? getInstance() : null;
 }

 @Override
 public String update() {
 // TODO Auto-generated method stub
 rowsToUpdate.clear();
 rowsToUpdate.add(currentRow);
 return super.update();
 }

 @Override
 public String persist() {
 // TODO Auto-generated method stub
 rowsToUpdate.clear();
 rowsToUpdate.add(currentRow);
 return super.persist();
 }


}

TDR