@Override
    public String toString() {
      return MoreObjects.toStringHelper(this).add("sourceBranch", sourceBranch)
          .add("targetBranch", targetBranch).toString();
    }
Value object class, that stores the fast-forward operation specific parameters.
<ul>
  <li>source branch: the branch which needs to be fast-forwarded</li>
<li>target branch: the branch to which the source branch needs to be fast-forwarded</li>
</ul>
ql/src/java/org/apache/hadoop/hive/ql/parse/AlterTableExecuteSpec.java