Store ENUM value into database

Question

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I wan to use ENUM to map values into database table rows:

BusinessCustomersSearchParams:

@Getter
@Setter
public class BusinessCustomersSearchParams {

    private String title;

    private List<String> status;

    private LocalDateTime createdAt;

    private LocalDateTime updatedAt;
}

Specification:

@Override
public Page<BusinessCustomersFullDTO> findBusinessCustomers(BusinessCustomersSearchParams params, Pageable pageable)
{
    Specification<BusinessCustomers> spec = (root, query, cb) -> {
        List<Predicate> predicates = new ArrayList<>();
        if (params.getTitle() != null) {
            predicates.add(cb.like(cb.lower(root.get("description")), "%" + params.getTitle().toLowerCase() + "%"));
        }

        final List<String> statuses = Optional.ofNullable(params.getStatus()).orElse(Collections.emptyList());
        if (statuses != null && !statuses.isEmpty()){
            List<BusinessCustomersStatus> statusesAsEnum = statuses.stream()
                .map(status -> BusinessCustomersStatus.fromStatus(status))
                .collect(Collectors.toList())
                ;

            predicates.add(root.get("status").in(statusesAsEnum));
        }

        return cb.and(predicates.toArray(new Predicate[predicates.size()]));
    };
    return businessCustomersService.findAll(spec, pageable).map(businessCustomersMapper::toFullDTO);
}

AttributeConverter:

import javax.persistence.AttributeConverter;
import javax.persistence.Converter;

@Converter
public class BusinessCustomersStatusAttributeConverter
    implements AttributeConverter<BusinessCustomersStatus, String> {

  public String convertToDatabaseColumn( BusinessCustomersStatus value ) {
    if ( value == null ) {
      return null;
    }

    return value.getStatus();
  }

  public BusinessCustomersStatus convertToEntityAttribute( String value ) {
    if ( value == null ) {
      return null;
    }

    return BusinessCustomersStatus.fromStatus( value );
  }

}

Enum:

package org.merchant.database.service.businesscustomers;

public enum BusinessCustomersStatus {
    A("active"),
    O("onboarding"),
    N("not_verified"),
    V("verified"),
    S("suspended"),
    I("inactive");

    private String status;

    BusinessCustomersStatus(String status)
    {
        this.status = status;
    }

    public String getStatus() {
        return status;
    }

    public static BusinessCustomersStatus fromStatus(String status) {
        switch (status) {
            case "active": {
                return A;
            }

            case "onboarding": {
                return O;
            }

            case "not_verified": {
                return NV;
            }

            case "verified": {
                return V;
            }

            case "suspended": {
                return S;
            }

            case "inactive": {
                return I;
            }

            default: {
                throw new UnsupportedOperationException(
                    String.format("Unkhown status: '%s'", status)
                );
            }
        }
    }
}

Entity:

@Entity
@Table(name = "business_customers")
public class BusinessCustomers implements Serializable {
   
    ..........
    @Convert( converter = BusinessCustomersStatusAttributeConverter.class )
    private BusinessCustomersStatus status;
    ......
}

Full code example: https://github.com/rcbandit111/Search_specification_POC

I send http query with params list?size=5&page=0&status=active,suspended and I get result with capital letters "status": "ACTIVE".

I wan to search and get status from FE for status using status=active but store into database row field only symbol A.

How I can store into database the ENUM key A?

Answer 1

In order to store the actual enumeration value in the database, you can do two things.

One, as suggested by @PetarBivolarski, modify the method convertToDatabaseColumn in AttributeConverter and return value.name() instead of value.getStatus() . But please, be aware that in addition you will need to update the convertToEntityAttribute as well to take into account that change:

import javax.persistence.AttributeConverter;
import javax.persistence.Converter;

@Converter
public class BusinessCustomersStatusAttributeConverter
    implements AttributeConverter<BusinessCustomersStatus, String> {

  public String convertToDatabaseColumn( BusinessCustomersStatus value ) {
    if ( value == null ) {
      return null;
    }

    return value.name();
  }

  public BusinessCustomersStatus convertToEntityAttribute( String value ) {
    if ( value == null ) {
      return null;
    }

    return BusinessCustomersStatus.valueOf( value );
  }

}

If you think about it, a more straightforward solution will be just keep the status field as @Enumerated :

@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@Builder(toBuilder = true)
@Entity
@Table(name = "business_customers")
public class BusinessCustomers {

    //...

    @Enumerated(EnumType.STRING)
    @Column(name = "status", length = 20)
    private BusinessCustomersStatus status;

    //...
}

It is in addition more according to the rest of your code.

Regarding your second problem, the application is returning "status":"ACTIVE" because in BusinessCustomersFullDTO you are defining the status field as String and this field receives the result of the mapping process performed by @Mapstruct and BusinessCustomersMapper .

To solve that issue, as I suggested you previously, you can modify your Mapper to handle the desired custom conversion:

import org.mapstruct.Mapper;
import org.mapstruct.Mapping;
import org.mapstruct.Named;
import org.merchant.config.BaseMapperConfig;
import org.merchant.database.entity.BusinessCustomers;
import org.merchant.database.service.businesscustomers.BusinessCustomersStatus;
import org.merchant.dto.businesscustomers.BusinessCustomersFullDTO;

@Mapper(config = BaseMapperConfig.class)
public interface BusinessCustomersMapper {

    @Mapping(source = "status", target = "status", qualifiedByName = "businessCustomersToDTOStatus")
    BusinessCustomersFullDTO toFullDTO(BusinessCustomers businessCustomers);


    @Named("busineessCustomersToDTOStatus")
    public static String businessCustomersToDTOStatus(final BusinessCustomersStatus status) {
        if (status == null) {
            return null;
        }

        return status.getStatus();
    }
}

If you do not prefer this solution, perhaps you can take a different approach: it will consist in the following. The idea is modifying the Jackson serialization and deserialization behavior of BusinessCustomersFullDTO . In fact, in your use case only is necessary to modify the serialization logic.

First, define the status field in BusinessCustomersFullDTO in terms of BusinessCustomersStatus as well:

@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@Builder(toBuilder = true)
public class BusinessCustomersFullDTO {

    private long id;

    private String name;

    private String businessType;

    private BusinessCustomersStatus status;

    private String description;

    private String country;

    private String address1;
}

To complete the solution, please, perform the following changes in the BusinessCustomersStatus enum:

public enum BusinessCustomersStatus {
    A("active"),
    O("onboarding"),
    NV("not_verified"),
    V("verified"),
    S("suspended"),
    I("inactive");

    private String status;

    BusinessCustomersStatus(String status)
    {
        this.status = status;
    }

    // Define the status field as the enum representation by using @JsonValue
    @JsonValue
    public String getStatus() {
        return status;
    }

    // Use the fromStatus method as @JsonCreator
    @JsonCreator
    public static BusinessCustomersStatus fromStatus(String status) {
        if (StringUtils.isEmpty(status)) {
            return null;
        }

        switch (status) {
            case "active": {
                return A;
            }

            case "onboarding": {
                return O;
            }

            case "not_verified": {
                return NV;
            }

            case "verified": {
                return V;
            }

            case "suspended": {
                return S;
            }

            case "inactive": {
                return I;
            }

            default: {
                throw new UnsupportedOperationException(
                        String.format("Unkhown status: '%s'", status)
                );
            }
        }
    }
}

Note the inclusion of the @JsonValue and @JsonCreator annotations: the later is using for deserialization which seems unnecessary to me in your application, but just in case.

Please, see the relevant documentation of the provided Jackson annotations.

Answer 2

Notice your convertToDatabaseColumn() method in BusinessCustomersStatusAttributeConverter .

It should return value.name() instead of value.getStatus() .