Java @Value 在 Spring Boot 测试中“无法解析占位符”
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/33256702/
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
@Value "Could not resolve placeholder" in Spring Boot Test
提问by u1559249
I want to take a Junit test for Spring-boot as below:
我想对 Spring-boot 进行 Junit 测试，如下所示：
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = {ApplicationTest.class})
public class TestOnSpring {
@Value("${app.name}")
private String appName;
@Test
public void testValue(){
System.out.println(appName);
}
}
and ApplicationTest.java like this
和 ApplicationTest.java 像这样
@ComponentScan("org.nerve.jiepu")
@EnableAutoConfiguration()
public class ApplicationTest {
public static void main(String[] args) {
SpringApplication.run(ApplicationTest.class, args);
}
}
and my POM like this:
和我的 POM 是这样的：
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.3.0.BUILD-SNAPSHOT</version>
</parent>
When I run the test, I got below error information
当我运行测试时，我得到以下错误信息
Caused by: java.lang.IllegalArgumentException: Could not resolve placeholder 'app.name' in string value "${app.name}"
at org.springframework.util.PropertyPlaceholderHelper.parseStringValue(PropertyPlaceholderHelper.java:174)
at org.springframework.util.PropertyPlaceholderHelper.replacePlaceholders(PropertyPlaceholderHelper.java:126)
at org.springframework.core.env.AbstractPropertyResolver.doResolvePlaceholders(AbstractPropertyResolver.java:204)
at org.springframework.core.env.AbstractPropertyResolver.resolveRequiredPlaceholders(AbstractPropertyResolver.java:178)
at org.springframework.context.support.PropertySourcesPlaceholderConfigurer.resolveStringValue(PropertySourcesPlaceholderConfigurer.java:172)
at org.springframework.beans.factory.support.AbstractBeanFactory.resolveEmbeddedValue(AbstractBeanFactory.java:807)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1027)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1014)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:543)
... 31 more
But When I run this application as normal Java Application
但是当我像普通 Java 应用程序一样运行这个应用程序时
@SpringBootApplication
public class Application {
public static void main(String[] args){
SpringApplication.run(Application.class, args);
}
}
It work well!
它运作良好！
What's wrong with it ? How should I take the junit test with Spring-boot? Thanks a lot!
它出什么问题了 ？我应该如何使用 Spring-boot 进行 junit 测试？非常感谢！
采纳答案by Maleen Abewardana
You need to add
你需要添加
@PropertySource("classpath:application.properties")
@PropertySource("classpath:application.properties")
to your class, so it will pick your normal configurations.
到你的班级，所以它会选择你的正常配置。
If you need different configurations for test you can add
如果您需要不同的配置进行测试，您可以添加
@TestPropertySource(locations="classpath:test.properties")
@TestPropertySource(locations="classpath:test.properties")
If not just copy paste your config file totest/resourcesfolder, then boot will pick from there.
如果不只是将您的配置文件复制粘贴到test/resources文件夹，则启动将从那里选择。
See this.
看到这个。
回答by nucatus
You can use the @SpringBootTestthat will do create the PropertySourcesPlaceholderConfigurerautomatically.
您可以使用@SpringBootTest将PropertySourcesPlaceholderConfigurer自动创建的。
This is described in the Testing chapter of the Spring Boot documentation.
这在 Spring Boot 文档的测试章节中有描述。
回答by horizon7
You have annotated your test class with @ContextConfiguration(classes = {ApplicationTest.class}). Wherein ApplicationTest.classdoes the component scan on a mentioned package. When you run your test it tries to find the configuration from the resources folder in 'main' instead of 'test'. If you annotate your class with @SpringBootTest(classes = {ClassToBeTested.class})or just @SpringBootTestin this particular case, I think (not 100% sure) it will create a limited context and pick up the properties from test/resources.
您已使用@ContextConfiguration(classes = {ApplicationTest.class}). 其中ApplicationTest.class组件扫描提到的包。当您运行测试时，它会尝试从“main”而不是“test”的资源文件夹中查找配置。如果您使用@SpringBootTest(classes = {ClassToBeTested.class})或仅@SpringBootTest在这种特殊情况下注释您的类，我认为（不是 100% 确定）它将创建一个有限的上下文并从测试/资源中获取属性。
If your properties are test specific, you can name your properties/yml file as application-test.propertiesor application-test.yml. And use @ActiveProfiles("test")in your test class so that it will always read test specific properties file.
如果您的属性是特定于测试的，您可以将您的属性/yml 文件命名为application-test.properties或application-test.yml。并@ActiveProfiles("test")在您的测试类中使用，以便它始终读取测试特定的属性文件。
I usually use this solution which works for me.
我通常使用这个对我有用的解决方案。
