Could not find datasource

[pedjasmek]

I'm getting "Could not find datasource" message when I run my jpa project.This is my persistence.xml file:
[code]
<?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="Prodavnica_jpa"
                transaction-type="JTA">
                <provider>
                        org.hibernate.ejb.HibernatePersistence
                </provider>
                <jta-data-source>java:/JPATestDataSource</jta-data-source>
                <class>com.spinnaker.pedja.Book</class>
                <class>com.spinnaker.pedja.Cart</class>
                <class>com.spinnaker.pedja.CartItem</class>
                <class>com.spinnaker.pedja.Customer</class>
                <class>com.spinnaker.pedja.Item</class>
                <class>com.spinnaker.pedja.Music</class>
                <class>com.spinnaker.pedja.Video</class>

                <properties>
                        <property name="hibernate.show_sql" value="false" />
                        <property name="hibernate.format_sql" value="true" />

                        <property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/>

                        <property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/shop" />
                       
                        <property name="hibernate.connection.username" value="root"/>
                        <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect" />
<!-- <property name="jboss.entity.manager.factory.jndi.name"-->
<!-- value="java:/MyProjectEntityManagerFactory" />-->

                        <property name="hibernate.hbm2ddl.auto" value="update" />
                       
                </properties>
        </persistence-unit>
</persistence>
[/code]
Let me know if I should add additional info.
How should I fix this problem?Thanks