public function testSetGetFactoryClass() {
$def = new Definition('stdClass');
$this
->assertNull($def
->getFactoryClass());
$this
->assertSame($def, $def
->setFactoryClass('stdClass2'), "->setFactoryClass() implements a fluent interface.");
$this
->assertEquals('stdClass2', $def
->getFactoryClass(), "->getFactoryClass() returns current class to construct this service.");
}