public void setGroupId(String groupId) {
        this.groupId = groupId;
    }
<p>
The optional group identifier of the document from the search service. Documents with the same group identifier
are grouped together and processed as one document within the service.
</p>

@param groupId
       The optional group identifier of the document from the search service. Documents with the same group
       identifier are grouped together and processed as one document within the service.
aws-java-sdk-kendraranking/src/main/java/com/amazonaws/services/kendraranking/model/Document.java