JPA – must be in the connectiondrivername property “how do I resolve it?” Specify the jdbc driver or datasource class name in

Overview: This is my first WebSphere 7 server & amp; JPA 1.0 & EJB & Derby database

Second: This is persistence XML file

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="1.0"
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">
<persistence-unit name="ShopJPA" transaction-type="JTA">
    <jta-data-source>jdbc/EJB3BANK</jta-data-source>
    <non-jta-data-source>jdbc/EJB3BANK</non-jta-data-source>
    <properties>
        <property name="openjpa.jdbc.Schema" value="SHOP" />
    </properties>
</persistence-unit>
</persistence>

Third: part of the code of the item entity class

@Entity
@Table(schema = "SHOP",name = "ITEM")
@NamedQuery(name = "getItem",query = "SELECT i FROM Item i")
public class Item{...}

Fourth: here is the business class cartbean. Here is the beginning of the problem

@Stateful
CartBean implements Cart{
....
....
public List<Item> getItems() {      
javax.persistence.Query query = em.createNamedQuery("getItem");//the problem here
return query.getResultList();
}
}

This is an error message: the jdbc driver or datasource class name must be specified in the connectiondrivername property How to solve this problem?

Solution

If you refer to a data source by JNDI name, you do not need to use openjpa Connectiondrivername property

One possible cause of this problem is persistence XML is in the wrong location The file must be located in the root directory of [class context] / meta inf For War file, the content should be similar to:

(foo.war)
WEB-INF/classes/Meta-INF/persistence.xml
WEB-INF/classes/com/foo123/jpa/Project.class
WEB-INF/web.xml
index.jsp

For A library packaged in a war file Jar file:

(foo.war)
WEB-INF/lib/my-library.jar
WEB-INF/web.xml
index.jsp

(my-library.jar)
Meta-INF/persistence.xml
com/foo123/jpa/Project.class