Giriş
QueryDSL dinamik sorguları kolaylaştırır.
1. Maven veya gradle dependency eklenir
2. JPA Entity tanımlanır
3. Q Sınıfları için kod üretilir
4. QuerydslPredicateExecutor sınıfından kalıtan bir repository yaratılır veya
JPAQueryFactory direkt kullanılır
MavenÖrnek
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<!-- Query DSL -->
<dependency>
<groupId>com.querydsl</groupId>
<artifactId>querydsl-apt</artifactId>
</dependency>
<dependency>
<groupId>com.querydsl</groupId>
<artifactId>querydsl-jpa</artifactId>
</dependency>
Örnek
Şöyle
yaparız. Burada
querydsl-apt provided olarak belirtiliyor.
<dependency>
<groupId>com.querydsl</groupId>
<artifactId>querydsl-jpa</artifactId>
<version>5.0.0</version>
</dependency>
<dependency>
<groupId>com.querydsl</groupId>
<artifactId>querydsl-apt</artifactId>
<version>5.0.0</version>
<scope>provided</scope>
</dependency>
Maven Plugin
Örnek - JPAAnnotationProcessor<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>
JPAQueryFactory Kullanımı
Örnek
mport com.querydsl.jpa.impl.JPAQueryFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import javax.persistence.EntityManager;
import java.util.List;
@Repository
public class PersonRepository {
@Autowired
private EntityManager entityManager;
public List<Person> findPeopleByLastName(String lastName) {
JPAQueryFactory queryFactory = new JPAQueryFactory(entityManager);
QPerson person = QPerson.person;
return queryFactory.selectFrom(person)
.where(person.lastName.eq(lastName))
.fetch();
}
}Test için şöyle yaparız
import com.querydsl.jpa.impl.JPAQueryFactory;
@SpringBootTest
@ActiveProfiles("test")
@Transactional
public class PersonRepositoryTest {
@Autowired
private PersonRepository personRepository;
@Autowired
private EntityManager entityManager;
@Test
void testFindPeopleByLastName() {
Person person1 = new Person();
person1.setFirstName("John");
person1.setLastName("Smith");
entityManager.persist(person1);
Person person2 = new Person();
person2.setFirstName("Jane");
person2.setLastName("Doe");
entityManager.persist(person2);
List<Person> result = personRepository.findPeopleByLastName("Smith");
assertThat(result).hasSize(1);
assertThat(result.get(0).getFirstName()).isEqualTo("John");
assertThat(result.get(0).getLastName()).isEqualTo("Smith");
}
}
QuerydslPredicateExecutor Kullanımı
import com.querydsl.core.types.dsl.BooleanExpression;
import com.querydsl.core.types.dsl.DatePath;
import com.querydsl.core.types.dsl.NumberPath;
import com.querydsl.core.types.dsl.PathBuilder;
import com.querydsl.core.types.dsl.StringPath;
gibi sınıflar ile bir path yaratılır
Örnek
Örnek
Elimizde şöyle bir Entity
olsunimport org.hibernate.annotations.Type;
import org.hibernate.annotations.TypeDef;
import com.vladmihalcea.hibernate.type.json.JsonType;
import lombok.Data;
@Entity
@Table(name = "abhi_roles")
@Data
@TypeDef(name = "json", typeClass = JsonType.class)
public class Roles implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@Column(name = "employeeId", length = 10)
private String employeeId;
@Column(name = "username")
private String username;
@Type(type = "json")
@Column(name = "roles", columnDefinition = "json")
private List<String> roles;
}import org.springframework.data.querydsl.QuerydslPredicateExecutor;
@Repository
public interface RolesRepository extends
JpaRepository<Roles, String>, QuerydslPredicateExecutor<Roles> {
}
import com.querydsl.core.types.dsl.BooleanExpression;
import com.querydsl.core.types.dsl.Expressions;
@Service
public class RolesService {
@Autowired
RolesRepository repository;
public List<Roles> findUsersWithRoles(String role) {
QRoles userRolesPath = QRoles.roles1;
BooleanExpression exp = Expressions
.booleanTemplate("json_contains_key({0}, {1})", userRolesPath.roles,
Expressions.constant(role))
.isTrue();
Iterable<Roles> lr = repository.findAll(exp);
List<Roles> result = new ArrayList<>();
lr.forEach(result::add);
return result;
}
}
