Question

I have a class like that:

@Override
public StudentDTO getStudent(@WebParam(name = "name") String studentName) {
    StudentDTO student = new StudentDTO();
    try {
        student = studentService.findStudentByName(studentName);
    } catch (Exception e) {
        return new ErrorActionResponse("student couldn't find by name");
    }
    return student;
}

As usual this doesn’t work because of return type is StudentDTO and I try to return another type of class: ErrorActionResponse. ErrorActionResponse is an error class that has detailed information about error.

How can I design my web service architecture that can handle error situations? (At my REST architecture I write error information into response and send error to client side)

Answer 1

If you want to return a Collection (as stated in a comment to my earlier answer), I suggest you create a Map with two keys. If there is no exception, first key-value pair will contain “students” string and StudentDTO collection, respectively. And, second key-value pair will contain “exception” string and null value, respectively. If there is an exception, first key-value pair will contain “students” string and null value, respectively. And, second key-value pair will be “exception” string and an ErrorActionResponse object, respectively. Example:

No exception case:

Map<String, List> result = new HashMap<String, List>();
result.put( "students", COLLECTION_OF_STUDENTS );
result.put( "exception", null );

No exception case:

Map<String, List> result = new HashMap<String, List>();
result.put( "students", null );
result.put( "exception", ErrorActionResponse_OBJECT );

Hope this helps…