Question

我有以下课程：

@ConfigurationProperties
public class Database {

   ...

   @Value("${database.driver-class-name}")
   public void setDriverClassName(String driverClassName) {
      ...
   }

在build.gradle中有以下依赖项：

dependencies {
    compile('org.springframework.boot:spring-boot-starter-jdbc')
    compile('org.springframework.boot:spring-boot-configuration-processor')

在application.properties中有以下一行：

database.driver-class-name=com.mysql.jdbc.Driver

在测试类上有以下注释：

@RunWith(SpringJUnit4ClassRunner.class)
@SpringApplicationConfiguration(DatabaseTest.Context.class)
@EnableConfigurationProperties
public class DatabaseTest {

   @Configuration
   public static class Context {

      @Bean
      public Database database() {
         Database ans = new Database();
         return ans;
      }

   }

   @Autowired
   public Database database;

并且它既没有从属性文件中注入属性也没有发誓带有一些错误消息。

它还想要什么？

从属性文件中注入属性的必要条件是什么？

UDPATE

示例存储库：https://github.com/dims12/MinimalRequrementsToInjectPropertiesFromFile

Answer 1

您班上的@configurationProperties应该有@Bean或@Component注释，以便为弹簧注入属性值。有关属性的更多信息，请参见here

@ConfigurationProperties
@Component // or @Bean
public class Database {

Answer 2

Sorry, found an answer myself.

In the case of Spring Boot, a context configuration class is usually annotated with @SpringBootApplication which causes many things, including automatic finding an wiring of property files. This is invoked by @EnableAutoConfiguration, which is contained inside former annotation.

In my case, I have annotated context configuration class with plain-Spring @Configuration annotation only, because I was in JUnit test and thought it is not an application. In this case I was to add @EnableAutoConfiguration explicitly.

Probably I was also allowed to annotate context configuration class with @SpringBootApplication, but I didn't test it.

@EnableConfigurationProperties was not needed at all. Also no need for @ConfigurationProperties, and AutowiredAnnotationBeanPostProcessor.

Spring Boot中属性注入工作的必要条件和充分条件是什么？

2 个答案: