Spring 3.0.5 不会从属性评估 @Value 注释
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/5275724/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Spring 3.0.5 doesn't evaluate @Value annotation from properties
提问by Alex Yarmula
Trying to auto-wire properties to a bean in Spring 3.0.5.RELEASE, I'm using:
尝试将属性自动连接到Spring 3.0.5.RELEASE 中的 bean ，我正在使用：
config.properties:username=myusernamemain-components.xml:<context:property-placeholder location="classpath:config.properties" />MyClass:
@Service public class MyClass { @Value("${username}") private String username; ... }
config.properties：username=myusernamemain-components.xml：<context:property-placeholder location="classpath:config.properties" />我的课：
@Service public class MyClass { @Value("${username}") private String username; ... }
As a result, username gets set to literally"${username}", so the expression doesn't get parsed. My other auto-wired dependencies on this class get set, and Spring doesn't throw any exception. I also tried to add @Autowiredbut it didn't help.
结果，用户名被设置为字面意思"${username}"，所以表达式不会被解析。我对这个类的其他自动连接依赖被设置，并且 Spring 不会抛出任何异常。我也尝试添加，@Autowired但没有帮助。
If I parse properties to a separate bean and then use @Autowired+ @Qualifier, it works:
如果我将属性解析为一个单独的 bean，然后使用@Autowired+ @Qualifier，它会起作用：
<bean id="username" class="java.lang.String">
<constructor-arg value="${username}"/>
</bean>
Any ideas how to use just @Value? Maybe I need to include some Spring dependency that I haven't? Thank you
任何想法如何使用 just @Value？也许我需要包含一些我没有的 Spring 依赖项？谢谢
采纳答案by Alex Yarmula
Found what the issue was. Copy/paste from comments:
找到了问题所在。从评论中复制/粘贴：
Are you sure you have <context:property-placeholder>in the same application context as your MyClass bean (not in the parent context)? – axtavt
您确定您<context:property-placeholder>的应用程序上下文与 MyClass bean 相同（不在父上下文中）？– axtavt
You're right. I moved <context:property-placeholder>from the context defined by the ContextLoaderListenerto the servlet context. Now my values get parsed. Thanks a lot! - alex
你是对的。我<context:property-placeholder>从 定义的上下文转移ContextLoaderListener到 servlet 上下文。现在我的价值观得到解析。非常感谢！- 亚历克斯
