Why my <p:dataExporter> doesn't work?

Question

I made my code like de PF Showcase, but it does't works... When i click my commandLink nothing happens. Anyone can help me? I already added Apache POI and iText.

        <h:form id="form">
            <p:commandButton value="Novo" icon="ui-icon-document"
                actionListener="#{controleBean.novoReservatorio()}" process="@this"
                update="dataTable reservatorio-dialog"
                oncomplete="PF('reservatorioDialog').show()" class="botaoDataTable">
                <p:resetInput target="reservatorio-dialog" />
            </p:commandButton>

            <p:commandButton icon="ui-icon-pencil" id="btnEditar" title="Editar"
                disabled="#{controleBean.reservatorio == null}"
                class="botaoDataTable" process="@this" update="dataTable :form"
                oncomplete="PF('reservatorioDialog').show()">
                <p:resetInput target="reservatorio-dialog" />
                <f:setPropertyActionListener target="#{controleBean.reservatorio}"
                    value="#{controleBean.reservatorioSelecao}" />
            </p:commandButton>

            <p:commandButton icon="ui-icon-trash" id="btnExcluir"
                title="Excluir" disabled="#{controleBean.reservatorio == null}"
                class="botaoDataTable" action="#{controleBean.excluirReservatorio}"
                process="@this" update="dataTable btnExcluir btnEditar" /> 

            <p:dataTable var="r" value="#{controleBean.reservatorios}"
                paginator="true" rows="30" id="dataTable"
                emptyMessage="Nenhum Reservatorio Cadastrado"
                paginatorPosition="bottom" 
                selection="#{controleBean.reservatorioSelecao}"
                selectionMode="single" rowKey="#{r.idReservatorio}"> 

                <p:ajax event="rowSelect"
                    update=":form:btnEditar :form:btnExcluir" />
                <p:ajax event="rowUnselect"
                    update=":form:btnEditar :form:btnExcluir" />

                <p:column headerText="Nome">
                    <h:outputText value="#{r.nomeReservatorio}" />
                </p:column>

                <p:column headerText="Capacidade (Lt)">
                    <h:outputText value="#{r.capacidadeReservatorio}" />
                </p:column>

                <p:column headerText="Tipo">
                    <h:outputText value="#{r.tipoReservatorio}" />
                </p:column>

                <p:column headerText="Observação">
                    <h:outputText value="#{r.obsReservatorio}" />
                </p:column>
            </p:dataTable>

            <p:commandLink>
                <p:graphicImage library="img" name="xlsx.png" width="32" title="Exportar para Excel"/>
                <p:dataExporter type="xls" target="dataTable" fileName="Relatorio" />
            </p:commandLink> 

            <h:commandLink>
                <p:graphicImage library="img" name="pdf.png" width="37" title="Exportar para PDF"/>
                <p:dataExporter type="pdf" target="dataTable" fileName="Relatorio"/>
            </h:commandLink>

            <p:commandButton value="Exportar para PDF" ajax="false">
                <p:dataExporter type="pdf" target=":form:dataTable" fileName="dataTable" />
            </p:commandButton>

            <p:dialog header="Reservatório" widgetVar="reservatorioDialog"
                id="reservatorio-dialog" resizable="false" modal="true"
                closeOnEscape="true">
                <p:messages style="font-size:70%;" />

                <p:panelGrid styleClass="semBorda">
                    <p:row>
                        <p:column>
                            <h:outputLabel for="nomeReservatorio" value="* Nome: "
                                class="componentePF label" />
                        </p:column>
                        <p:column>
                            <p:inputText id="nomeReservatorio" required="true"
                                value="#{controleBean.reservatorio.nomeReservatorio}"
                                requiredMessage="É necessário atribuir um nome à reservatorio"
                                class="componentePF text" />
                        </p:column>
                    </p:row>

                    <p:row>
                        <p:column>
                            <h:outputLabel for="capacidadeReservatorio"
                                value="* Capacidade (Lt): " class="componentePF label" />
                        </p:column>
                        <p:column>
                            <p:spinner id="capacidadeReservatorio" size="30"
                                value="#{controleBean.reservatorio.capacidadeReservatorio}"
                                min="0" stepFactor="1" required="true"
                                requiredMessage="É necessário atribuir uma capacidade à reservatorio"
                                class="componentePF text" />
                        </p:column>
                    </p:row>

                    <p:row>
                        <p:column>
                            <h:outputLabel for="tipoReservatorio"
                                value="* Tipo de Reservatório: " class="componentePF label" />
                        </p:column>
                        <p:column>
                            <p:selectOneMenu id="tipoReservatorio"  style="font-size:75% !important;"
                                value="#{controleBean.reservatorio.tipoReservatorio}"
                                class="componentePF text bold" required="true"
                                requiredMessage="É necessário atribuir um tipo ao reservatório">
                                <f:selectItem itemLabel="Escolha um Tipo para o Reservatório"
                                    noSelectionOption="true" />
                                <f:selectItem itemLabel="Escoamento" itemValue="Escoamento" />
                                <f:selectItem itemLabel="Reserva" itemValue="Reserva" />
                            </p:selectOneMenu>

                        </p:column>
                    </p:row>

                    <p:row>
                        <p:column>
                            <h:outputLabel for="obsReservatorio" value="Observação: "
                                class="componentePF label" />
                        </p:column>
                        <p:column>
                            <p:inputText id="obsReservatorio"
                                value="#{controleBean.reservatorio.obsReservatorio}"
                                class="componentePF text" />
                        </p:column>
                    </p:row>

                    <p:row>
                        <p:column colspan="2">
                            <p:commandButton value="Cadastrar" icon="ui-icon-disk"
                                action="#{controleBean.cadastrarReservatorio}"
                                id="cadastrarReservatorio" ajax="false"
                                class="componentePF button" />
                        </p:column>
                    </p:row>
                </p:panelGrid>
            </p:dialog>
        </h:form>

Answer 1

The first <p:commandLink> doesn't work be cause it sends an ajax request. Just add ajax="false" to solve the problem.

See https://stackoverflow.com/a/7740280/1980659 for the root cause explanation.

With what you provided the two other buttons should work.