spring mvc nested model validation

Question

I have two models : User,Project

public class Project{
    private int id;
    @NotEmpty(message=\"Project Name can not be empty\")
    private          


        

Answer 1

Here's one possible solution.

Create the class below :

...
import org.springframework.validation.Validator;
...

@Component
public class ProjectValidator implements Validator {

    @Override
    public boolean supports(Class clazz) {
        return Project.class.equals(clazz);
    }

    @Override
    public void validate(Object target, Errors errors) {
        Project project = (Project) target;

        /* Do your checks here */
        ...

        if (managerIdDoesNotMatch) {
            errors.rejectValue("manager.id", "your_error_code");
        }

        ...

        if (operatorIdDoesNotMatch) {
            errors.rejectValue("operator.id", "your_error_code");
        }

        ...
    }
}

And in your controller do something like :

...
public class ProjectController {

    @Autowired
    ProjectValidator projectValidator;

    ...

    @RequestMapping(...)
    public String yourCreateMethod(..., @ModelAttribute @Valid Project project, BindingResult result) {
        projectValidator.validate(project, result);           

        if (result.hasErrors()){
          // do something
        }
        else {
          // do something else
        }
    }

}

This should get you started. You could instantiate/set the validator differently, have a a user sub-validator, but you get the general idea.

References :

• Latest Spring validation documentation
• This Stack Overflow post about how to perform validation