Spring CRUDRepository findBy Multiple fields - spring-boot

Question

if my EmployeeEntity contains multiple fields:
first_name
last_name
department
office_name
state,
etc..
is there a way that I can have JUST ONE find...() interface in my CRUDRepository interface to search for employee(s) based on the query parameters without hardcode the interface?
http://localhost:8080/employees?last_name='me'&state='tx'
or
http://localhost:8080/employee?state='tx'&office_name='alpha'

Answer 1

You could use QueryDSL to generate any queries on your repository dynamically, based on your entity fields.
To integrate it with Spring Data JPA, add the following two dependencies and the JPA annotation processor to your project:
<dependency>
<groupId>com.querydsl</groupId>
<artifactId>querydsl-apt</artifactId>
<version>4.1.4</version>
</dependency>
<dependency>
<groupId>com.querydsl</groupId>
<artifactId>querydsl-jpa</artifactId>
<version>4.1.4</version>
</dependency>
<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.mysema.query.apt.jpa.JPAAnnotationProcessor</processor>
</configuration>
</execution>
</executions>
</plugin>
…and extend your repository in some kind of that way:
public interface EmployeeRepository extends JpaRepository<EmployeeEntity, Long>,
QuerydslPredicateExecutor<EmployeeEntity>, QuerydslBinderCustomizer<QEmployeeEntity> {
}
Now you are able to express all kind of query combinations:
BooleanExpression name = QEmployeeEntity.employeeEntity.last_name.eq("brawn");
BooleanExpression stateAndName = QEmployeeEntity.employeeEntity.state.eq("tx").and(name);
Please consult also the Spring Data JPA reference manual for further features.