code: public SignUpRequest withValidationData(AttributeType... validationData) {
          if (this.validationData == null) {
              setValidationData(new java.util.ArrayList<AttributeType>(validationData.length));
          }
          for (AttributeType ele : validationData) {
              this.validationData.add(ele);
          }
          return this;
      }
docs: <p>
  The validation data in the request to register a user.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setValidationData(java.util.Collection)} or {@link #withValidationData(java.util.Collection)} if you want
  to override the existing values.
  </p>
  
  @param validationData
  The validation data in the request to register a user.
  @return Returns a reference to this object so that method calls can be chained together.