Query DSL, Criteria 설정

1. Dependencies

• compile "org.springframework:spring-orm:4.3.11.RELEASE"
• compile "org.springframework.data:spring-data-jpa:1.11.7.RELEASE"
• compile "org.hibernate:hibernate-core:5.2.11.Final"
• compile "org.hibernate:hibernate-entitymanager:5.2.11.Final"
• compile "com.querydsl:querydsl-jpa:4.1.3"

2. Plugin setting

• Maven

<project>

  <build>

  <plugins>

    

    //QueryDSL

    <plugin>

      <groupId>com.mysema.maven</groupId>

      <artifactId>apt-maven-plugin</artifactId>

      <version>1.1.3</version>

      <executions>

        <execution>

          <goals>

            <goal>process</goal>

          </goals>

          <configuration>

            <outputDirectory>target/generated-sources/java</outputDirectory>

            <processor>com.querydsl.apt.jpa.JPAAnnotationProcessor</processor>

          </configuration>

        </execution>

      </executions>

    </plugin>




    //Criteria

    <plugin>

      <groupId>org.apache.maven.plugins</groupId>

      <artifactId>maven-compiler-plugin</artifactId>

      <version>3.7.0</version>

      <configuration>

        <source>1.8</source>

        <target>1.8</target>

        <encoding>UTF-8</encoding>

        <compilerArguments>

          <processor>org.hibernate.jpamodelgen.JPAMetaModelEntityProcessor</processor>

        </compilerArguments>

      </configuration>

    </plugin>




  </plugins>

  </build>

</project>

• Gradle

repositories {

mavenCentral()

}




afterEvaluate {

def processors = new LinkedHashSet()




configurations.runtime.resolvedConfiguration.resolvedArtifacts.each { raf ->

def cid = raf.getModuleVersion().getId()




if (cid.group.equals('com.querydsl') && cid.name.equals('querydsl-core')) {

def queryDslAptVersion = cid.version

logger.info "[jpaModelGen-${project.name}] querydsl-apt version ${queryDslAptVersion}"

dependencies {

jpaMetamodelGen "com.querydsl:querydsl-apt:${queryDslAptVersion}"

}




processors << 'com.querydsl.apt.jpa.JPAAnnotationProcessor'

}




if (cid.group.equals('org.hibernate') && cid.name.equals('hibernate-core')) {

def hibernateJpaModelGenVersion = cid.version

dependencies {

jpaMetamodelGen "org.hibernate:hibernate-jpamodelgen:${hibernateJpaModelGenVersion}"

}




processors << 'org.hibernate.jpamodelgen.JPAMetaModelEntityProcessor'

}

}

}




sourceSets {

main {

java {

srcDir 'src/generated/java-jpa'

}

}

}

3. How to use

• QueryDSL
1. Repositroy에 "QueryDslPredicateExecutor"와 "CustomRepository"를 상속받는다.
2. CustomRepository의 구현체 RepositoryImpl을 생성한다.
3. 사용할 Query를 작성한다.
• Criteria
1. Repository에 "JpaSpecificationExecutor"를 상속 받는다.
2. Criteria (specification)을 작성한다.

4. Example

QueryDSL

@Repository
public class CardRepositoryImpl implements CardRepositoryCustom {

   @PersistenceContext(unitName = "kanban")
   private EntityManager entityManager;

   @Override
   public List<Card> search(String title, CardStatus status, String color) {

      JPAQuery jpaQuery = new JPAQuery(entityManager);
      QCard card = QCard.card;

      jpaQuery.from(card)
         .where(card.title.like("%" + title + "%"))
         .where(card.status.eq(status))
         .where(card.color.eq(color))
         .orderBy(card.id.desc());

      return jpaQuery.fetch();
   }
}

Criteria

public class QuerySpec<T> {
   public Specification<T> equal(SingularAttribute<T, String> attribute, String value) {
      if (StringUtils.isBlank(value)) {
         return null;
      }

      return (root, query, builder) -> builder.equal(root.get(attribute), value);
   }
}

** 참고하면 좋은 블로그

• https://jojoldu.tistory.com/372
• http://kwonnam.pe.kr/wiki/gradle/jpa_metamodel_generation