code: protected void validateDate(final List<Diagnostic> diags) {
  		Date value = getValue();
  		if (value == null) {
  			return;
  		}
  
  		Date min = getMinDate();
  		Date max = getMaxDate();
  
  		if (min != null && value.compareTo(min) < 0) {
  			diags.add(createErrorDiagnostic(
  					InternalMessages.DEFAULT_VALIDATION_ERROR_DATE_AFTER_OR_EQUAL, this, min));
  		}
  
  		if (max != null && value.compareTo(max) > 0) {
  			diags.add(createErrorDiagnostic(
  					InternalMessages.DEFAULT_VALIDATION_ERROR_DATE_BEFORE_OR_EQUAL, this, max));
  		}
  	}
docs: <p>
  Performs validation of the date. Validation ensures that the entered date is between the minimum/maximum values
  (if applicable).
  </p>
  <p>
  Subclasses can override this method to perform more specific validation.
  </p>
  
  @param diags the list into which any validation diagnostics are added.