Specifications and Criteria-Based Dynamic Filtering
Compose type-safe dynamic predicates with the JPA Specification API for runtime-driven filtering.
Why Dynamic Filtering?
Real applications rarely query with fixed criteria. A product search screen might filter by name, category, price range, or any combination the user picks at runtime.
Writing a separate repository method for every combination explodes fast: findByName, findByNameAndCategory, findByCategoryAndPriceBetween... This does not scale.
Spring Data JPA's Specification API lets you compose type-safe query fragments at runtime and combine them with and() / or(). In this lesson you'll build dynamic predicates the clean way.
Enabling Specifications on a Repository
To use Specifications, your repository must extend JpaSpecificationExecutor<T> in addition to JpaRepository.
This adds overloaded methods such as findAll(Specification<T>), findAll(Specification, Pageable), findOne(Specification), and count(Specification).
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
public interface ProductRepository
extends JpaRepository<Product, Long>,
JpaSpecificationExecutor<Product> {
}All lessons in this course
- Derived Query Methods and Keyword Resolution
- JPQL and Native Queries with @Query
- Specifications and Criteria-Based Dynamic Filtering
- Pagination, Sorting, and Slice Streaming