[3부: 스프링 부트 원리] 11. 자동 설정 만들기 2부: @ConfigurationProperties

[changju]

3부: 스프링 부트 원리

11. 자동 설정 만들기 2부: @ ConfigurationProperties

• 덮어쓰기 방지하기

  • @ ConditionalOnMissingBean

• 빈 재정의 수고 덜기

  • @ ConfigurationProperties(“holoman”)
  • @ EnableConfigurationProperties(HolomanProperties)
  • 프로퍼티 키값 자동 완성

    
    <dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-configuration-processor</artifactId>
    <optional>true</optional>
    </dependency>

[changju]

AutoConfiguration

<project xmlns="...">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.study.springboot</groupId>
    <artifactId>spring-boot-chap3-10-autoconfiguration-2-provider</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-autoconfigure</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-autoconfigure-processor</artifactId>
            <optional>true</optional>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.16.20</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>2.0.3.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

</project>

@Configuration
@EnableConfigurationProperties(PrettyFatherProperties.class)
public class PrettyFatherConfiguration {
    @Bean
    @ConditionalOnMissingBean // 등록이 되어진 bean 이 없으면 등록 하여
    public PrettyFather prettyFather(PrettyFatherProperties properties) {
        PrettyFather pFather = new PrettyFather();
        pFather.setName(properties.getName());
        pFather.setOld(properties.getOld());
        return pFather;
    }
}

@Getter
@Setter
@ToString
@ConfigurationProperties("prettyfather")
public class PrettyFatherProperties {
    String name;
    int old;

}

[changju]

UseConfiguration

• Properties 설정

  prettyfather.name = changjulee
  prettyfather.old = 20

• Autowired

  @Component
  public class PrettyFatherRunner implements ApplicationRunner{
  
  @Autowired
  PrettyFather prettyFather;
  
  @Override
  public void run(ApplicationArguments args) throws Exception {
      System.out.println(prettyFather);
  }
  }

• @ Bean

  @SpringBootApplication
  public class Application {
  
  public static void main(String[] args) {
      // TODO Auto-generated method stub
  
      SpringApplication application = new SpringApplication(Application.class);
      application.setWebApplicationType(WebApplicationType.NONE);
      application.run(args);
  }
  
  /*
   * ComponentScan 으로 Bean으로 등록이 된다.
   * EnableAutoConfiguration 에서 등록을 하기 때문에  오버라이드 된다.
   * @ConditionalOnMissingBean의 의미는 Bean의 정의가 안되어 있다면, 내가 정의한 Bean은 사용 할 수 없다.
   */
  @Bean
  public PrettyFather prettyFather()
  {
      PrettyFather prettyFather =  new PrettyFather();
      prettyFather.setName("cblee");
      prettyFather.setOld(29);
      return prettyFather;
  }
  }