O erro acontece nessa parte do codigo
<h:commandButton value="Gravar" action="#{livroBean.gravar}">
<f:ajax execute="@form" render="@form :tabelaLivros" />
</h:commandButton>
</h:form>
<h:dataTable value="#{livroBean.livro}" var="livros" id="tabelaLivros">
<h:column>
<f:facet name="header">Título</f:facet>
<h:outputText value="#{livro.titulo}" />
</h:column>
<h:column>
<f:facet name="header">ISBN</f:facet>
<h:outputText value="#{livro.isbn}" />
</h:column>
<h:column>
<f:facet name="header">Preço</f:facet>
<h:outputText value="#{livro.preco}">
<f:convertNumber type="currency" pattern="R$ #0.00"
currencySymbol="R$" locale="pt_BR" />
</h:outputText>
</h:column>
<h:column>
<f:facet name="header">Data</f:facet>
<h:outputText value="#{livro.dataLancamento.time}">
<f:convertDateTime pattern="dd/MM/yyyy" timeZone="America/Sao_Paulo" />
</h:outputText>
</h:column>
</h:dataTable>
erro que aparece:
jun 27, 2019 5:10:59 PM org.apache.catalina.core.StandardWrapperValve invoke
GRAVE: Servlet.service() for servlet [Faces Servlet] in context with path [/livraria] threw exception [javax/servlet/jsp/jstl/sql/Result] with root cause
java.lang.ClassNotFoundException: javax.servlet.jsp.jstl.sql.Result
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1364)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1185)
at javax.faces.component.UIData.getDataModel(UIData.java:1806)
at javax.faces.component.UIData.setRowIndexWithoutRowStatePreserved(UIData.java:483)
at javax.faces.component.UIData.setRowIndex(UIData.java:472)
at com.sun.faces.renderkit.html_basic.TableRenderer.encodeBegin(TableRenderer.java:82)
at javax.faces.component.UIComponentBase.encodeBegin(UIComponentBase.java:820)
at javax.faces.component.UIData.encodeBegin(UIData.java:1117)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1777)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1782)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1782)
at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:437)
at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:124)
at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:120)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:594)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:493)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:137)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:660)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:798)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:808)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1498)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)