output: #fixed code
                                  private boolean internalRemove(T element) {
          boolean success = false;
          if (element != null) {
              Integer lrem = nest.cat(JOhmUtils.getId(owner))
                      .cat(field.getName()).lrem(1,
                              JOhmUtils.getId(element).toString());
              unindexValue(element);
              success = lrem > 0;
          }
          return success;
      }
input: #vulnerable code 
                                  private boolean internalRemove(T element) {
          Integer lrem = nest.cat(JOhmUtils.getId(owner)).cat(field.getName())
                  .lrem(1, JOhmUtils.getId(element).toString());
          unindexValue(element);
          return lrem > 0;
      } 
                              #location 3 
                              #vulnerability type NULL_DEREFERENCE