public function getAdapter() {
		if ($this->_adapter === null) {
			if ($this->hasLocator()) {
				$this->_adapter = $this->getLocator()->get($this->getAdapterName());
			} else {
				throw new Exceptions\NoAdapter('Nor a database adapter neither a services locator has been provided');
			}
		}
		
		return $this->_adapter;
	}