How to modify the messages example to connect to Oracle DB

[monkeyknifefight]

Hey guys another newbie question here. I'm trying to modify the messages example to connect to an Oracle database, then execute a simple query and display the results in a table. I'm having problems getting my configuration set up correctly. I added a -ds.xml file and edited the persistence.xml file to point to that datasource. Then I use the @PersistenceContext annotation to try to get a hold of that datasource and run the query. Problem I am having is:

javax.faces.el.EvaluationException: Cannot get value for expression '#{messageList.rowCount==0}

I assume because the query doesn't return anything. I'll post my config files and the code that executes the query. Am I on the right track with the configuration or just chasing my tail?

Thanks
Chris

persistence.xml

<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd"
 version="1.0">
 <persistence-unit name="userDatabase">
 <provider>org.hibernate.ejb.HibernatePersistence</provider>
 <jta-data-source>java:/XAOracleDS</jta-data-source>
 <properties>
 <property name="hibernate.dialect" value="org.hibernate.dialect.Oracle9Dialect" />
 <property name="hibernate.connection.driver_class" value="oracle.jdbc.driver.OracleDriver" />
 <property name="hibernate.connection.username" value="USER" />
 <property name="hibernate.connection.password" value="PASS" />
 <property name="hibernate.connection.datasource" value="java:/XAOracleDS"/>
 </properties>
 </persistence-unit>
</persistence>

oracle-xa-ds.xml

<datasources>
 <xa-datasource>
 <jndi-name>XAOracleDS</jndi-name>
 <track-connection-by-tx>true</track-connection-by-tx>
 <isSameRM-override-value>false</isSameRM-override-value>
 <xa-datasource-class>oracle.jdbc.xa.client.OracleXADataSource</xa-datasource-class>
 <xa-datasource-property name="URL">
 jdbc:oracle:thin:@funeral:1521:DB
 </xa-datasource-property>
 <xa-datasource-property name="User">USER</xa-datasource-property>
 <xa-datasource-property name="Password">PASS</xa-datasource-property>
 <exception-sorter-class-name>
 org.jboss.resource.adapter.jdbc.vendor.OracleExceptionSorter
 </exception-sorter-class-name>
 <no-tx-separate-pools/>
 </xa-datasource>

 <mbean code="org.jboss.resource.adapter.jdbc.vendor.OracleXAExceptionFormatter"
name="jboss.jca:service=OracleXAExceptionFormatter">
 <depends optional-attribute-name="TransactionManagerService">
 jboss:service=TransactionManager
 </depends>
 </mbean>
</datasources>

MessageManagerBean.java

//$Id: MessageManagerBean.java,v 1.7 2006/11/19 21:01:33 gavin Exp $
package org.jboss.seam.example.messagesTest;

import static javax.persistence.PersistenceContextType.EXTENDED;
import static org.jboss.seam.ScopeType.SESSION;

import java.io.Serializable;
import java.util.List;

import javax.ejb.Remove;
import javax.ejb.Stateful;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;

import org.jboss.seam.annotations.Destroy;
import org.jboss.seam.annotations.Factory;
import org.jboss.seam.annotations.Name;
import org.jboss.seam.annotations.Out;
import org.jboss.seam.annotations.In;
import org.jboss.seam.annotations.Scope;
import org.jboss.seam.annotations.datamodel.DataModel;
import org.jboss.seam.annotations.datamodel.DataModelSelection;

@Stateful
@Scope(SESSION)
@Name("messageManagerTest")
public class MessageManagerBean implements Serializable, MessageManager
{

 @DataModel
 private List<Message> messageList;

 @DataModelSelection
 @Out(required=false)
 private Message message;

 @PersistenceContext(type=EXTENDED)
 private EntityManager em;

 @Factory("messageList")
 public void findMessages()
 {
 messageList = em.createQuery("select unitid from iped_hd").getResultList();
 }

 @Remove @Destroy
 public void destroy() {}

}

messages.jsp

<%@ taglib uri="http://java.sun.com/jsf/html" prefix="h" %>
<%@ taglib uri="http://java.sun.com/jsf/core" prefix="f" %>
<%@ taglib uri="http://jboss.com/products/seam/taglib" prefix="s" %>
<html>
 <head>
 <title>Messages</title>
 </head>
 <body>
 <f:view>
 <h2>Message List</h2>
 <h:outputText value="No messages to display" rendered="#{messageList.rowCount==0}"/>
 <h:dataTable var="msg" value="#{messageList}" rendered="#{messageList.rowCount>0}">
 <h:column>
 <f:facet name="header">
 <h:outputText value="Title"/>
 </f:facet>
 <h:outputText value="#{msg.unitid}"/>
 </h:column>
 </h:dataTable>
 </f:view>
 </body>
</html>

[fhh]

Hello!

javax.faces.el.EvaluationException: Cannot get value for expression '#{messageList.rowCount==0}

This is not the real exception but the one that came out of the application stack.

I assume the real problem is that you are trying to execute a sql query through the entity manager instead of defning entity beans and using EJBQL.

You can use bare SQL but then you have to inject a datasource into your session bean using the @Resource annotation.

Regards

Felix