Modern web applications often require dynamic search functionality — filtering by optional fields, sorting by user input, and paginating results. Traditional JPA queries or @Query annotations in Spring Data can become verbose and inflexible.

That’s where QueryDSL shines. It allows you to build type-safe, composable, and dynamic queries in Java. In this guide, we’ll walk through how to use QueryDSL with Spring Boot to create powerful and reusable search APIs.

Why Use QueryDSL?

  • Type-safe query construction using generated classes
  • Readable and composable fluent APIs
  • Perfect for dynamic filters and search endpoints
  • Seamless integration with Spring Data JPA

QueryDSL generates meta-model classes (like QUser) that let you construct queries fluently without using raw SQL or fragile strings.

Setting Up QueryDSL in Spring Boot

Add the required dependencies in pom.xml:

<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>

Configure annotation processing (e.g., with Maven):

<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>

Create an Entity and Generate Query Types

Example JPA entity:

@Entity
public class Product {
@Id
@GeneratedValue
private Long id;

    private String name;
    private Double price;
    private String category;
}

Once compiled, a QProduct class will be generated.

Building a Dynamic Search Query

Use JPAQueryFactory to construct dynamic search queries:

public List<Product> searchProducts(String name, String category, Double maxPrice) {
QProduct product = QProduct.product;

    BooleanBuilder builder = new BooleanBuilder();
    if (name != null) builder.and(product.name.containsIgnoreCase(name));
    if (category != null) builder.and(product.category.eq(category));
    if (maxPrice != null) builder.and(product.price.lt(maxPrice));

    return queryFactory
        .selectFrom(product)
        .where(builder)
        .fetch();
}

This allows filtering by any combination of parameters.

Integrating with Spring Data

You can extend QuerydslPredicateExecutor in your repository:

public interface ProductRepository extends JpaRepository<Product, Long>,
QuerydslPredicateExecutor<Product> {}

Now you can call:

repository.findAll(product.name.containsIgnoreCase("book")
.and(product.category.eq("Education")));

Adding Pagination and Sorting

QueryDSL supports pageable queries:

Page<Product> page = productRepository.findAll(builder, PageRequest.of(0, 10, Sort.by("price").descending()));

You can also expose a search endpoint:

@GetMapping("/products/search")
public Page<Product> search(@RequestParam Map<String, String> params, Pageable pageable) {
// build BooleanBuilder dynamically from params
return repository.findAll(builder, pageable);
}

Conclusion

QueryDSL brings type-safety and flexibility to dynamic query building in Spring Boot. It’s ideal for building search APIs that need to adapt to user input, support filtering on multiple optional parameters, and scale well with pagination and sorting.

With just a little setup, you can dramatically improve the maintainability and expressiveness of your JPA-based search layers.