anchor.diff:                              <div class="col-md-6">
                                   <input type="text" id="category" class="form-control" value="${hp.categoryList}">
                                   <input type="hidden" id="categoryId" name="category">
  -                                <c:if test="${empty hp.id}">
  +                                <c:if test="${!empty hp.id}">
                                       <input type="hidden" id="categoryOld" value="${hp.category}">
                                   </c:if>
                               </div>
  
positive.code:                             <div class="col-md-6">
                                  <input type="text" id="color" class="form-control"  value="${hp.colorList}">
                                  <input type="hidden" id="colorId" name="color">
                                  <c:if test="${empty hp.id}">
                                      <input type="hidden" id="colorOld" value="${hp.color}">
                                  </c:if>
                              </div>
  
negative.code:                             <div class="col-md-6">
                                  <input type="text" id="brand" class="form-control" value="${hp.brandList}">
                                  <input type="hidden" id="brandId" name="brand">
                                  <c:if test="${!empty hp.id}">
                                      <input type="hidden" id="brandOld" value="${hp.brand}">
                                  </c:if>
                              </div>
  