在我的Springboot项目中，如何使用@Value注解获取Properties文件中的属性值

Question

There are two classes and a configuration file, but they are all in the test directory I want to use the @Value annotation in class A to get the attribute value, and then assemble class A in class B, use the method in class A, I want to output the value obtained from the configuration file, but in fact it is all null How can i fix it！！！ eg：

class structure:

class A

Class B

properteis

But if I turn Class A into a test class, I can get the results I want the result as follow

Answer 1

You need to autowire class A in class B . Instead of using the spring managed bean with injected @Value you are creating a new class resulting in the variables in class A to be null.

@SpringBootTest
@Import(A.class)
public class B {

  @Autowire
  private final A a;
}