Starter & AutoConfigure

구현방법

1. 의존성 추가

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example.study1</groupId>
    <artifactId>cheolju-spring-boot-starter</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>

    <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.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </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>

2. @Configuration 파일 작성

@Bean
public Man holoMan(){
    return Man.builder()
            .name("cheolju")
            .age(5)
            .build();
}

3. src/main/resource/META-INF spring.factories 파일생성

4. spring.factories 안에 자동 설정 파일 추가 

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
  study1.HoloManConfiguration

5. mvn install -> local project 내에서 사용 가능

6. 다른 local project 에서 dependency 설정

<dependency>
   <groupId>org.example.study1</groupId>
   <artifactId>cheolju-spring-boot-starter</artifactId>
   <version>1.0-SNAPSHOT</version>
</dependency>

* 다른 local project에서 같은 이름으로 bean을 등록하는 경우 Componemt-scan으로 등록된 bean이 우선이라 덮어 쓰여짐

     > @ConditionalOnMissingBean 를 사용하여 덮어쓰기 방지

 

* 빈을 재정의 하기 싫은 경우

     > Properties Class 생성 후

@Configuration
@EnableConfigurationProperties(ManProperties.class) //추가
public class ManConfiguration {

    @Bean
    @ConditionalOnMissingBean
    public Man Man(ManProperties properties){
        return Man.builder()
                .name(properties.getName())
                .age(properties.getAge())
                .build();
    }
}