Class is managed, but is not listed in the persistence.xml file

If you are using Eclipse:(1) Select: (Your Project) -> Properties -> JPA;(2) Look for "Persistent class management" and select the option "Discover annotated classes automatically";(3) Press "Apply".

If it is an Eclipse problem, go to:

Preferences >> Java Persistence >> JPA >> Errors/Warnings >> Type

in the following itens, mark then as Ignore:

• Class is annotated, but is not listed in the persistence.xml file
• Class is managed, but is not listed in the persistence.xml file

If you are using Spring you could avoid persistence.xml file and declare instead an entity manager factory like this:

<bean id="entityManagerFactory"    class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">    <property name="dataSource" ref="yourDataSource" />    <property name="packagesToScan" value="com.testApp.domain" />    <property name="jpaVendorAdapter">        <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">            <property name="databasePlatform" value="org.hibernate.dialect.HSQLDialect" />        </bean>    </property></bean>

All the entities in com.testApp.domain package (marked with @Entity annotation) will be loaded without declaring them in XML.

UPDATE You need to declarate a data source, for example:

<bean id="yourDataSource" class="org.apache.commons.dbcp.BasicDataSource">    <property name="driverClassName" value="org.hsqldb.jdbcDriver" />    <property name="url" value="jdbc:hsqldb:mem:." />    <property name="username" value="SA" />    <property name="password" value="" />    <property name="initialSize" value="5" />    <property name="maxActive" value="20" /></bean>

Then you can use the entityManager exactly as you were doing. I suppose you are using something similar in your DAO classes:

@PersistenceContextprivate EntityManager em;