Openjpa SQL log output and connection pool usage

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• How do I see the SQL that openjpa is executing?

How do I see the SQL that openjpa is executing?

Openjpa provides retriable channel-based logging, as described in the chapter on logging. The simplest example of enabling verbose logging is by using the following property in yourPersistence. xmlFile:

<persistence xmlns="http://java.sun.com/xml/ns/persistence"    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"    version="1.0">    <persistence-unit name="example-logging" transaction-type="RESOURCE_LOCAL">        <properties>            <property name="openjpa.Log" value="SQL=TRACE"/>        </properties>    </persistence-unit></persistence>

How do I enable Connection pooling in openjpa?

Openjpa doesn' t include any built-in connection pool, but you can use any third-party connection pool that is accessible via the JDBC datasource API (which most are). The followingPersistence. xmlExample shows how to use openjpa with a Apache Derby database and the Apache DBCP connection pool:

<persistence xmlns="http://java.sun.com/xml/ns/persistence"    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"    version="1.0">    <persistence-unit name="example-derby" transaction-type="RESOURCE_LOCAL">        <properties>            <property name="openjpa.ConnectionProperties"                 value="DriverClassName=org.apache.derby.jdbc.ClientDriver,                  Url=jdbc:derby://localhost:1527/database,                   MaxActive=100,                   MaxWait=10000,                   TestOnBorrow=true,                   Username=user,                   Password=secret"/>            <property name="openjpa.ConnectionDriverName"                 value="org.apache.commons.dbcp.BasicDataSource"/>        </properties>    </persistence-unit></persistence>

See the documentation on using a third-party datasource for further details.