Spring-boot application-test.properties

Question

I am trying to unit test the spring-boot application using junit. I have placed the application-test.properties under src/test/resources. I have a ApplicationConfiguration C

Answer 1

The issue is you don't have @EnableConfigurationProperties on your test class.
When you load the application it start from main class(one which has @SpringBootApplication) where you might have @EnableConfigurationProperties and hence it works when you start the application.
Whereas when you are running the Test with only ApplicationConfiguration class as you have specified here

@SpringBootTest(classes=ApplicationConfiguration.class)

Spring doesn't know that it has to Enable Configuration Properties and hence the fields are not injecting and hence null. But spring is reading your application-test.properties file. This can be confirmed by just injecting the value directly in your test class

@Value("${xxxxx}")
private String xxxxx;

Here the value is injected. But to inject into a class with ConfigurationProperties you need to enable it using @EnableConfigurationProperties

Put @EnableConfigurationProperties on your test class and everythhing works fine.