not work on Spring Boot Test

I want to take a Junit test for Spring-boot as below:

@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

@ComponentScan("org.nerve.jiepu")@EnableAutoConfiguration()public class ApplicationTest {    public static void main(String[] args) {        SpringApplication.run(ApplicationTest.class, args);    }}

and my POM like this:

    
             
     
      org.springframework.boot
             
     
      spring-boot-starter-parent
             
     
      1.3.0.BUILD-SNAPSHOT
         
    

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$2.resolveStringValue(PropertySourcesPlaceholderConfigurer.java:172)    at org.springframework.beans.factory.support.AbstractBeanFactory.resolveEmbeddedValue(AbstractBeanFactory.java:807)    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1027)    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1014)    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:543)    ... 31 more

@SpringBootApplicationpublic class Application {    public static void main(String[] args){        SpringApplication.run(Application.class, args);    }}

It work well!

What's wrong with it ? How should I take the junit test with Spring-boot? Thanks a lot!

Answer：

You can use the @SpringBootTest that will do create the PropertySourcesPlaceholderConfigurer automatically.

This is described in the Testing chapter of the