How to call a stored procedure from Spring Data JPA and map the result to a custom object without having a corresponding entity?

Question

Question:

I'm working on a Spring Boot project where I need to call a stored procedure from my database using Spring Data JPA. The stored procedure returns a result set that I want to map to a custom Java object, but I don't want to create a corresponding entity for this object.

I've looked into using @NamedStoredProcedureQuery and @SqlResultSetMapping annotations to achieve this, but I'm facing some challenges. Can someone provide a clear example or guide on how to accomplish this task effectively? Additionally, are there any alternative approaches that I could consider for achieving the same result?

Any help or insights would be greatly appreciated. Thank you!

What I've found id @NamedStoredProcedureQuery along with @SqlResultSetMapping annotations to define the mapping between the stored procedure result set and my custom Java object. However, I found it challenging to implement this approach without having a corresponding entity class for the custom object.

Unfortunately, I couldn't find a clear and concise example or guide that demonstrates how to achieve this specific scenario. Therefore, I'm seeking guidance from the community on the best practices or alternative approaches to achieve my goal effectively.

Update on on more info of problem: Consider a scenario where you have a stored procedure in your database that returns a custom object representing details about employees, derived from multiple tables such as "employees", "departments", and "salaries". The stored procedure might return a result set containing attributes like employee name, department name, and salary amount and also array of them if required.

With plain JDBC, you might have code like this:

public class EmployeeDAO {
    public Employee getEmployeeDetails(int employeeId) {
        // Code to call stored procedure using JDBC and retrieve custom object
        // Mapping result set to a custom Java object representing employee details
        return employee;
    }
}

Now, if you want to switch to using JPA, you would typically create an entity class representing an Employee, mapped to the "employees" table:

@Entity
@Table(name = "employees")
public class Employee {
    @Id
    private int id;
    private String name;
    // Other attributes and getters/setters
}

However, the situation doesn't fit neatly into this model because the stored procedure combines data from multiple tables, and we don't have a single table that directly corresponds to the entity.