Let's create the class which inherits PDO class and setup the data source information by the constructor method. As an example, the following SqlitePdo class is created to /path/to/classes/SqlitePdo.php.

<?php
class SqlitePdo extends \PDO {
    public function __construct() {
        parent::__construct('sqlite:' . DB_DIR . '/sqlite.db');
        $this->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    }
}

Please create CdDao class which uses the created PDO class.

<?php
class CdDao {
    public $sqlitePdo = null;
    public function findAll() {
        $stmt = $this->sqlitePdo->prepare('select * from CD');
        $stmt->setFetchMode(PDO::FETCH_OBJ);
        $stmt->execute();
        return $stmt->fetchAll();
    }
}

PDO class and CdDao class are imported by S2ApplicationContext.

<?php
require_once('S2Container/S2Container.php');
define('DB_DIR', dirname(__FILE__) . '/db');
use seasar\container\S2ApplicationContext as s2app;

s2app::import(dirname(__FILE__) . '/classes');
$cdDao = s2app::get('CdDao');
var_dump($cdDao->findAll());

PDO is set up by a DICON file. As an example, please create following DICON file.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//SEASAR2.1//DTD S2Container//EN"
"http://www.seasar.org/dtd/components21.dtd">
<components>
   <component name="sqlitePdo" class="PDO">
       <arg>return 'sqlite:' . DB_DIR . '/sqlite.db'</arg>
   </component>
</components>

The DICON file and CdDao class are imported by S2ApplicationContext.

<?php
require_once('S2Container/S2Container.php');
use seasar\container\S2ApplicationContext as s2app;

s2app::import(dirname(__FILE__) . '/classes/CdDao.php');
s2app::import(dirname(__FILE__) . '/dicon');
$cdDao = s2app::get('CdDao');
var_dump($cdDao->findAll());