gistfile1.txt

<?xml version="1.0" encoding="UTF-8"?>
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<blueprint xmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0"
            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xmlns:cm="http://aries.apache.org/blueprint/xmlns/blueprint-cm/v1.0.0"
            default-activation="lazy">

  <!-- Property place holder -->
  <cm:property-placeholder persistent-id="org.openengsb.infrastructure.jpa">
    <cm:default-properties>
      <cm:property name="driverClassName" value="org.h2.jdbcx.JdbcDataSource" />
      <cm:property name="url" value="jdbc:h2:openengsb" />
      <cm:property name="username" value="" />
      <cm:property name="password" value="" />
      <cm:property name="validationQuery" value="SELECT 1" />
      <cm:property name="defaultReadOnly" value="false" />
      <cm:property name="defaultAutoCommit" value="true" />
      <cm:property name="maxActive" value="8" />
      <cm:property name="whenExhaustedAction" value="2" />
      <cm:property name="maxWait" value="-1" />
      <cm:property name="maxIdle" value="8" />
      <cm:property name="minIdle" value="0" />
      <cm:property name="testOnBorrow" value="true" />
      <cm:property name="testOnReturn" value="true" />
      <cm:property name="timeBetweenEvictionRunsMillis" value="-1" />
      <cm:property name="numTestsPerEvictionRun" value="3" />
      <cm:property name="minEvictableIdleTimeMillis" value="1800000" />
      <cm:property name="testWhileIdle" value="false" />
      <cm:property name="softMinEvictableIdleTimeMillis" value="-1" />
      <cm:property name="lifo" value="true" />
    </cm:default-properties>
  </cm:property-placeholder>

  <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
    <property name="driverClassName" value= "${driverClassName}" />
    <property name="url" value="${url}" />
    <property name="username" value="${username}" />
    <property name="password" value="${password}" />
    <property name="maxIdle" value="1" />
  </bean>

  <bean id="connectionFactory" class="org.apache.commons.dbcp.DataSourceConnectionFactory">
    <argument ref="dataSource" />
  </bean>

  <bean id="connectionPool" class="org.apache.commons.pool.impl.GenericObjectPool" >
    <argument><null/></argument>
    <argument value="${maxActive}" />
    <argument value="${whenExhaustedAction}" />
    <argument value="${maxWait}" />
    <argument value="${maxIdle}" />
    <argument value="${minIdle}" />
    <argument value="${testOnBorrow}" />
    <argument value="${testOnReturn}" />
    <argument value="${timeBetweenEvictionRunsMillis}" />
    <argument value="${numTestsPerEvictionRun}" />
    <argument value="${minEvictableIdleTimeMillis}" />
    <argument value="${testWhileIdle}" />
    <argument value="${softMinEvictableIdleTimeMillis}" />
    <argument value="${lifo}" />
  </bean>

  <bean id="pooledConnectionFactory" class="org.apache.commons.dbcp.PoolableConnectionFactory" >
    <argument ref="connectionFactory" />
    <argument ref="connectionPool" />
    <argument><null/></argument>
    <argument value="${validationQuery}" />
    <argument value="${defaultReadOnly}" />
    <argument value="${defaultAutoCommit}" />
  </bean>

  <bean id="poolingDataSource" class="org.apache.commons.dbcp.PoolingDataSource" depends-on="pooledConnectionFactory">
    <argument ref="connectionPool" />
  </bean>

  <service id="xaDataSource" ref="poolingDataSource" interface="javax.sql.DataSource">
    <service-properties>
      <entry key="osgi.jndi.service.name" value="jdbc/openengsb"/>
    </service-properties>
  </service>

</blueprint>

Hello,

The above blueprint is an excellent reference for implementing a PoolingDatasource.

It seems that one possible motivation to use a PoolingDatasource would be if one needs to have fine grained control over the ObjectPool used by it.

As far as I can tell (see this and this) a BasicDataSource should be sufficient ( a 'one-stop-shop') for most needs.

Why did you need to use a PoolingDataSource rather than a BasicDataSource?

Thanks !!
-Ash