<!-- context.xml -->

    <Resource name="jdbc/SomeDB" auth="Container" type="javax.sql.DataSource"
              maxActive="100" maxIdle="30" maxWait="10000"
              username="${mysql.username}" password="${mysql.password}" driverClassName="com.mysql.jdbc.Driver"
              removeAbandoned="true" removeAbandonedTimeout="30" logAbandoned="true"
              validationQuery="SELECT 1" testOnBorrow="true" testOnReturn="true"
              timeBetweenEvictionRunsMillis="30000" minEvictableIdleTimeMillis="28000" testWhileIdle="true"
              url="jdbc:mysql://${mysql.host}:3306/somedb"/>

<!-- persistence.xml -->
    <persistence-unit name="someDatabase" transaction-type="RESOURCE_LOCAL">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <jta-data-source>java:comp/env/jdbc/SomeDB</jta-data-source>
        <properties>
            <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
            <property name="hibernate.hbm2ddl.auto" value="validate"/>
            <property name="hibernate.show_sql" value="true"/>
            <property name="hibernate.cache.provider_class" value="org.hibernate.cache.HashtableCacheProvider"/>

            <property name="hibernate.c3p0.provider_class" value="org.hibernate.connection.C3P0ConnectionProvider" />
            <property name="hibernate.c3p0.acquire_increment" value="5" />
            <property name="hibernate.c3p0.idle_test_period" value="30" />
            <property name="hibernate.c3p0.timeout" value="30" />
            <property name="hibernate.c3p0.max_size" value="100" />
            <property name="hibernate.c3p0.min_size" value="5" />
            <property name="hibernate.c3p0.max_statements" value="0" />
            <property name="hibernate.c3p0.preferredTestQuery" value="select 1;" />
        </properties>