Question

Here is my validate method –

@Override
  public void validate() {
    errors = new HashMap<String, String>();
    if(StringUtil.isBlank(examCode)){
      errors.put("examCode", "Exam code is required");
    }
    if(StringUtil.isBlank(strPaperType)){
      errors.put("paperType", "Paper Type is required");
    }else{
      paperType = PaperType.getPaperTypeByValue(strPaperType);
      if(paperType == null){
        errors.put("paperType", "A valid Paper Type is required");
      }
      if(paperType.equals(PaperType.PRACTICE)){
        if(topicId ==null){
          errors.put("topicId", "Topic Id is required");
        }
      }
    }
    if(StringUtil.isBlank(instructions)){
      errors.put("instructions", "Paper Instructions are required");
    }
  }

‘errors’ is my own map defined in the action. I’m not adding any errors to ‘fieldErrors’. What’s happening is even before entering my ‘validate’ method if I debug ‘fieldErrors’ I see following two entries –

{"id":["Invalid field value for field \"id\"."],"topicId":["Invalid field value for field \"topicId\"."]}

I have no idea from where are they getting added. Here is my struts conf.

<package name="api" extends="json-default" namespace="/api">
    <action name="paper" class="paperApiAction">
      <result name="json" type="json">
        <param name="root">responseDto</param>
      </result>
      <result name="input" type="json">
        <param name="root">fieldErrors</param>
      </result>
    </action>
  </package>

Need help with this. Thanks

Answer 1

The “conversionError” interceptor will take type conversion errors and put them into fieldErrors. There are usecases where it’s easier to take it out of the stack; I’m not sure if this is one of them or not.

Why bother duplicating the fieldErrors map? Even if you just want to have a map for use in your own DTO, why not use the existing validation mechanisms? The difference is minuscule, and a bit more flexible. You could then build the paper type validation into externalized business logic and simplify testing both it, and the action.

---

Unrelated, but I find your code difficult to read because of the lack of whitespace. A naive refactoring:

@Override
public void validate() {
    errors = new HashMap<String, String>();

    if (StringUtil.isBlank(examCode)) {
        errors.put("examCode", "Exam code is required");
    }

    if (StringUtil.isBlank(instructions)) {
      errors.put("instructions", "Paper Instructions are required");
    }

    if (StringUtil.isBlank(strPaperType)) {
        errors.put("paperType", "Paper Type is required");
    } else {
        validatePaperType();
    }
}

public void validatePaperType() {
    paperType = PaperType.getPaperTypeByValue(strPaperType);
    if (paperType == null) {
        errors.put("paperType", "A valid Paper Type is required");
        return;
    }

    if (paperType.equals(PaperType.PRACTICE) && (topicId == null)) {
        errors.put("topicId", "Topic Id is required");
    }
}