Spring 3.0.5 不评估属性中的 @Value 注释 [英] Spring 3.0.5 doesn't evaluate @Value annotation from properties

问题描述

尝试将属性自动连接到 Spring 3.0.5.RELEASE 中的 bean，我正在使用:

Trying to auto-wire properties to a bean in Spring 3.0.5.RELEASE, I'm using:

• config.properties:

username=myusername

main-components.xml:

<context:property-placeholder location="classpath:config.properties" />

我的班级:

MyClass:

@Service
public class MyClass {

    @Value("${username}")
    private String username;
    ...
}

因此，用户名被设置为 literally "${username}"，因此表达式不会被解析.我对此类的其他自动关联依赖项已设置，并且 Spring 不会引发任何异常.我也尝试添加 @Autowired 但没有帮助.

As a result, username gets set to literally "${username}", so the expression doesn't get parsed. My other auto-wired dependencies on this class get set, and Spring doesn't throw any exception. I also tried to add @Autowired but it didn't help.

如果我将属性解析为单独的 bean，然后使用 @Autowired + @Qualifier，它可以工作:

If I parse properties to a separate bean and then use @Autowired + @Qualifier, it works:

<bean id="username" class="java.lang.String">
    <constructor-arg value="${username}"/>
</bean>

任何想法如何使用 @Value?也许我需要包含一些我没有的 Spring 依赖项?谢谢

Any ideas how to use just @Value? Maybe I need to include some Spring dependency that I haven't? Thank you

推荐答案

找到问题所在.从评论中复制/粘贴:

Found what the issue was. Copy/paste from comments:

您确定 <context:property-placeholder> 与 MyClass bean 在同一个应用程序上下文中(而不是在父上下文中)吗?– axtavt

Are you sure you have <context:property-placeholder> in the same application context as your MyClass bean (not in the parent context)? – axtavt

你是对的.我将 <context:property-placeholder> 从 ContextLoaderListener 定义的上下文移动到 servlet 上下文.现在我的值被解析了.非常感谢！- 亚历克斯

You're right. I moved <context:property-placeholder> from the context defined by the ContextLoaderListener to the servlet context. Now my values get parsed. Thanks a lot! - alex

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