public function instance($name, $instance) {
		list($name, $alias) = $this->extractName($name);

		$componentName = $this->getAlias($name);

		if ($this->isSingleton($componentName) && $this->resolved($componentName)) {
			throw new ComponentRegisterException('Can\'t register component, The ' . $name . ' component is singleton, and it had resolved');
		}

		if (!is_null($alias)) {
			$this->alias($alias, $name);
		}

		$this->instances[$name] = $instance;
	}