java - 如何为需要 MyClass.class 参数的工厂方法注入(inject) Spring Bean

Question

我正在尝试将 java.util.prefs.Preferences bean 注入(inject)到我的主 Controller 中。 Controller 看起来像:

@Controller
class MyController {
    @Autowired
    private Preferences preferences;
}

application-context.xml 文件为 java.util.prefs.Preferences 创建 bean。它使用工厂方法，所以我有以下条目来创建 bean:

<bean id="preferences" class="java.util.prefs.Preferences" factory-method="userNodeForPackage" />

Preferences.userNodeForPackage(param) 将与 Preference 相关的类作为参数。在这种情况下，Spring 需要通过执行调用来创建 bean:

Preferences.userNodeForPackage(MyController.class);

如何将一个类传递给使用工厂方法实例化的 Spring bean？谢谢

环境信息:

Java 7
Spring 3.1

Answer 1

你可以指定 constructor-arg 元素

<bean id="preferences" class="java.util.prefs.Preferences" factory-method="userNodeForPackage">
    <constructor-arg type="java.lang.Class" value="com.path.MyController" />
</bean>

这在官方文档here中有解释，第 5.4.1 节。

Arguments to the static factory method are supplied via elements, exactly the same as if a constructor had actually been used. The type of the class being returned by the factory method does not have to be of the same type as the class that contains the static factory method, although in this example it is. An instance (non-static) factory method would be used in an essentially identical fashion (aside from the use of the factory-bean attribute instead of the class attribute), so details will not be discussed here.