<?xml version="1.0" encoding="UTF-8"?>
<configuration status="error">
  <appenders>
    <Jdbc name="databaseAppender" tableName="application_log">
      <DriverManager url="jdbc:oracle:thin:@//localhost:1521/XE" username="system" password="system" />
      <Column name="level" pattern="%level" />
      <Column name="logger" pattern="%logger" />
      <Column name="message" pattern="%message" />
    </Jdbc>
  </appenders>
  <loggers>
    <root level="warn">
      <appender-ref ref="databaseAppender"/>
    </root>
  </loggers>
</configuration

<?xml version="1.0" encoding="UTF-8"?>
<configuration status="error">
  <appenders>
    <Jdbc name="databaseAppender" tableName="application_log">
      <ConnectionFactory class="net.example.db.ConnectionFactory" method="getDatabaseConnection" />
      <Column name="level" pattern="%level" />
      <Column name="logger" pattern="%logger" />
      <Column name="message" pattern="%message" />
    </Jdbc>
  </appenders>
  <loggers>
    <root level="warn">
      <appender-ref ref="databaseAppender"/>
    </root>
  </loggers>
</configuration

package net.example.db;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;

import javax.sql.DataSource;

import org.apache.commons.dbcp.DriverManagerConnectionFactory;
import org.apache.commons.dbcp.PoolableConnection;
import org.apache.commons.dbcp.PoolableConnectionFactory;
import org.apache.commons.dbcp.PoolingDataSource;
import org.apache.commons.pool.impl.GenericObjectPool;

public class ConnectionFactory {
    private static interface Singleton {
        final ConnectionFactory INSTANCE = new ConnectionFactory();
    }

    private final DataSource dataSource;

    private ConnectionFactory() {
        Properties properties = new Properties();
        properties.setProperty("user", "logging");
        properties.setProperty("password", "abc123"); // or get properties from some configuration file

        GenericObjectPool<PoolableConnection> pool = new GenericObjectPool<PoolableConnection>();
        DriverManagerConnectionFactory connectionFactory = new DriverManagerConnectionFactory(
                "jdbc:mysql://example.org:3306/exampleDb", properties
        );
        new PoolableConnectionFactory(
                connectionFactory, pool, null, "SELECT 1", 3, false, false, Connection.TRANSACTION_READ_COMMITTED
        );

        this.dataSource = new PoolingDataSource(pool);
    }

    public static Connection getDatabaseConnection() throws SQLException {
        return Singleton.INSTANCE.dataSource.getConnection();
    }
}