[FIXED] Failed to > convert from type [java.lang.Object[]] to type > [com.rh.app.batch.domain.A] java

Issue

I tried to get data from table B and saved it into Class Object A

 A sale = repository.getSale(m, stmtDate);

repository

public interface repository extends JpaRepository<B, String> {
@Query(value = " SELECT ID AS id FROM B...LEFT JOIN C ... ", nativeQuery = true)
    A getSale(@Param("m") String m, @Param("date") String stmtDate);
}

Class A

@Entity
public class A implements Serializable {

 private String id; 
 public String getID() {
        return id;
    }

    public void setID(String id) {
        this.id = id;
    }
  }
    .....

Error

org.springframework.core.convert.ConversionFailedException: Failed to convert from type [java.lang.Object[]] to type [com.rh.app.batch.domain.A] for value '{0e89c64c-d840-45c5-9c6a-bda52fbaa7d1, 201802, 5.000, 1, 0, 0}'; nested exception is org.springframework.core.convert.ConverterNotFoundException: No converter found capable of converting from type [java.lang.String] to type [com.rh.app.batch.domain.A]

Solution

I am not sure if that is what you are looking for but, when you want to map the results of a complex query into one object, you can use the SqlResultSetMapping annotation:

Assuming you have a class like.

public class PersonDTO {

private String name;
private Date birthDate;
//omit other attributes 

public Person(String name, Date birthDate) {
  this.name = name;
  this.birthDate = birthDate;

}

you decorate it as follows.

@SqlResultSetMapping(name="PersonDTOMapping",
                     classes="@ConstructorResult(
                     targetClass= PersonDTO.class,
                     columns = {@ColumnResult(name="name"),
                                @ColumnResult(name="birhDate")}))

and your query becomes:

PersonDTO person = (PersonDTO) em.createNativeQuery("select p.name, p.birthDate as date from person where p.id=1", "PersonDTOMapping").getSingleResult();

please let me know, if this is what you re looking for.

Answered By - Eirini Graonidou
Answer Checked By - Pedro (JavaFixing Volunteer)