Java 解决 JUnit 测试中的 Spring @Value 表达式
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/20879608/
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
Resolve Spring @Value expression in JUnit tests
提问by Harold L. Brown
Here's a snippet of a Spring bean:
这是 Spring bean 的一个片段：
@Component
public class Bean {
@Value("${bean.timeout:60}")
private Integer timeout;
// ...
}
Now I want to test this bean with a JUnit test. I'm therefore using the SpringJUnit4ClassRunnerand the ContextConfigurationannotation.
现在我想用 JUnit 测试来测试这个 bean。因此，我使用SpringJUnit4ClassRunner和ContextConfiguration注释。
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration
public class BeanTest {
@Autowired
private Bean bean;
// tests ...
@Configuration
public static class SpringConfiguration {
@Bean
public Bean bean() {
return new Bean();
}
}
}
Unfortunately the SpringJUnit4ClassRunner can't resolve the @Valueexpression, even though a default value is supplied (a NumberFormatExceptionis thrown). It seems that the runner isn't even able to parse the expression.
不幸的是 SpringJUnit4ClassRunner 无法解析@Value表达式，即使提供了默认值（抛出NumberFormatException）。似乎跑步者甚至无法解析表达式。
Is something missing in my test?
我的测试中缺少什么吗？
采纳答案by nobeh
Your test @Configurationclass is missing an instance of PropertyPlaceholderConfigurerand that's why Spring does not know how to resolve those expressions; add a bean like the following to your SpringConfigurationclass
您的测试@Configuration类缺少一个实例，PropertyPlaceholderConfigurer这就是 Spring 不知道如何解析这些表达式的原因；将如下所示的 bean 添加到您的SpringConfiguration类中
@org.springframework.context.annotation.Bean
public static PropertyPlaceholderConfigurer propertyPlaceholderConfigurer() {
PropertyPlaceholderConfigurer ppc = new PropertyPlaceholderConfigurer();
ppc.setIgnoreResourceNotFound(true);
return ppc;
}
and move it to a separate class and use
并将其移动到一个单独的类并使用
@ContextConfiguration(classes=SpringConfiguration.class)
to be more specific when running your test.
在运行测试时更具体。
