public String shortString() {
        return shortString;
    }
Returns a short string representation of this {@link RowKindEnum}.

<ul>
  <li>"+I" represents {@link #INSERT}.
  <li>"-U" represents {@link #UPDATE_BEFORE}.
  <li>"+U" represents {@link #UPDATE_AFTER}.
  <li>"-D" represents {@link #DELETE}.
</ul>
inlong-common/src/main/java/org/apache/inlong/common/enums/RowKindEnum.java