Package in.co.akshitbansal.springwebquery

Class RsqlSpecificationArgumentResolver

java.lang.Object
in.co.akshitbansal.springwebquery.RsqlSpecificationArgumentResolver
All Implemented Interfaces:
org.springframework.web.method.support.HandlerMethodArgumentResolver
public class RsqlSpecificationArgumentResolver extends Object implements org.springframework.web.method.support.HandlerMethodArgumentResolver
Spring MVC HandlerMethodArgumentResolver that resolves controller method parameters annotated with RsqlSpec into Spring Data JPA Specifications.

This resolver enables transparent usage of RSQL queries in controller methods. When a request contains an RSQL query parameter, the resolver:

  1. Resolves entity metadata and aliases from WebQuery on the controller method
  2. Parses the RSQL query string into an AST
  3. Validates the AST against the target entity using ValidationRSQLVisitor
  4. Converts the validated query into a Specification using RSQLJPASupport

If the RSQL query parameter is missing or blank, the resolver returns an unrestricted Specification (equivalent to no filtering).

Example controller usage:


 @GetMapping("/users")
 @WebQuery(entityClass = User.class)
 public List<User> search(
     @RsqlSpec Specification<User> spec
 ) {
     return userRepository.findAll(spec);
 }

This resolver must be registered via WebMvcConfigurer to be active.

See Also:

  • Constructor Summary

    Constructors
    Constructor
    Description
    RsqlSpecificationArgumentResolver(Set<RsqlOperator> defaultOperators, Set<? extends RsqlCustomOperator<?>> customOperators)
    Creates a new RsqlSpecificationArgumentResolver with the specified operators.

  • Method Summary

    Modifier and Type
    Method
    Description
    org.springframework.data.jpa.domain.Specification<?>
    resolveArgument(@NonNull org.springframework.core.MethodParameter parameter, org.springframework.web.method.support.ModelAndViewContainer mavContainer, @NonNull org.springframework.web.context.request.NativeWebRequest webRequest, org.springframework.web.bind.support.WebDataBinderFactory binderFactory)
    Resolves the controller method argument into a Specification.
    boolean
    supportsParameter(org.springframework.core.MethodParameter parameter)
    Determines whether this resolver supports the given method parameter.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • RsqlSpecificationArgumentResolver

      public RsqlSpecificationArgumentResolver(Set<RsqlOperator> defaultOperators, Set<? extends RsqlCustomOperator<?>> customOperators)
      Creates a new RsqlSpecificationArgumentResolver with the specified operators.
      Parameters:
      defaultOperators - set of default RSQL operators to support
      customOperators - set of custom RSQL operators to support

  • Method Details

    • supportsParameter

      public boolean supportsParameter(org.springframework.core.MethodParameter parameter)
      Determines whether this resolver supports the given method parameter.

      A parameter is supported if:

      • It is assignable to Specification
      • It is annotated with RsqlSpec
      Specified by:
      supportsParameter in interface org.springframework.web.method.support.HandlerMethodArgumentResolver
      Parameters:
      parameter - the method parameter to check
      Returns:
      true if this resolver supports the parameter

    • resolveArgument

      public org.springframework.data.jpa.domain.Specification<?> resolveArgument(@NonNull @NonNull org.springframework.core.MethodParameter parameter, org.springframework.web.method.support.ModelAndViewContainer mavContainer, @NonNull @NonNull org.springframework.web.context.request.NativeWebRequest webRequest, org.springframework.web.bind.support.WebDataBinderFactory binderFactory)
      Resolves the controller method argument into a Specification.

      The RSQL query is read from the request parameter defined by RsqlSpec.paramName(). Entity metadata and alias mappings are read from WebQuery on the same controller method. The query is then parsed, validated, and converted into a JPA Specification.

      Specified by:
      resolveArgument in interface org.springframework.web.method.support.HandlerMethodArgumentResolver
      Parameters:
      parameter - the method parameter to resolve
      mavContainer - the model and view container
      webRequest - the current web request
      binderFactory - the data binder factory
      Returns:
      a Specification representing the RSQL query, or an unrestricted Specification if the query is absent
      Throws:
      QueryValidationException - if the RSQL query is invalid or violates RsqlFilterable constraints
      QueryConfigurationException - if query metadata or field mapping configuration is invalid