TreeTable - Sort Sibling nodes can be sorted within a parent.
Document Viewer
NameSizeType
<h:form>
    <p:treeTable value="#{ttBasicView.root}" var="document">
        <f:facet name="header">
            Document Viewer
        </f:facet>
        <p:column headerText="Name" sortBy="#{document.name}">
            <h:outputText value="#{document.name}" />
        </p:column>
        <p:column headerText="Size" sortBy="#{document.size}">
            <h:outputText value="#{document.size}" />
        </p:column>
        <p:column headerText="Type"  sortBy="#{document.type}">
            <h:outputText value="#{document.type}" />
        </p:column>
    </p:treeTable>
</h:form>
                
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