code: protected void parseComment() {
          String comment = tokenizer.getToken();
          if (isTargetComment(comment)) {
              if (isIfComment(comment)) {
                  parseIf();
              } else if (isBeginComment(comment)) {
                  parseBegin();
              } else if (isEndComment(comment)) {
                  return;
              } else {
                  parseCommentBindVariable();
              }
          } else if(isHintComment(comment)){
              peek().addChild(new SqlNode("/*" + comment + "*/"));
          }
      }
docs: Parse an SQL comment.