在展示中 http://www.primefaces.org/showcase/ui/datatableRowSelectionByColumn.jsf
当用户单击行上的编辑按钮时，我们调用
<f:setPropertyActionListener value="#{car}" target="#{tableBean.selectedCar}" />
设置 selectedCar 之后update=":form:display"将更新h:outputText对话框中的数据并显示。
但是当我将其更改为不再<h:outputText>起作用时，它会引发异常。这是代码和异常：datatableRowSelection.xhtml<h:inputText><f:setPropertyActionListener>
<h:form id="form">
<p:growl id="msgs" showDetail="true" />
<p:dataTable id="cars" var="car" value="#{tableBean.carsSmall}">
<p:column headerText="Model" style="width:24%">
<h:outputText value="#{car.model}" />
</p:column>
<p:column headerText="Year" style="width:24%">
<h:outputText value="#{car.year}" />
</p:column>
<p:column headerText="Manufacturer" style="width:24%">
<h:outputText value="#{car.manufacturer}" />
</p:column>
<p:column headerText="Color" style="width:24%">
<h:outputText value="#{car.color}" />
</p:column>
<p:column style="width:4%">
<p:commandButton id="selectButton" update=":form:display" oncomplete="carDialog.show()" icon="ui-icon-search" title="View">
<f:setPropertyActionListener value="#{car}" target="#{tableBean.selectedCar}" />
</p:commandButton>
</p:column>
</p:dataTable>
<p:dialog header="Car Detail" widgetVar="carDialog" resizable="false" id="carDlg"
showEffect="fade" hideEffect="explode" modal="true">
<h:panelGrid id="display" columns="2" cellpadding="4" style="margin:0 auto;">
<f:facet name="header">
<p:graphicImage value="/images/cars/#{tableBean.selectedCar.manufacturer}.jpg"/>
</f:facet>
<h:outputText value="Model:" />
<h:outputText value="#{tableBean.selectedCar.model}" style="font-weight:bold"/>
<h:outputText value="Year:" />
<h:outputText value="#{tableBean.selectedCar.year}" style="font-weight:bold"/>
<h:outputText value="Manufacturer:" />
<h:inputText value="#{tableBean.selectedCar.manufacturer}" style="font-weight:bold"/> <!-- I changed outputText to inputText here -->
<h:outputText value="Color:" />
<h:inputText value="#{tableBean.selectedCar.color}" style="font-weight:bold"/> <!-- I changed outputText to inputText here -->
</h:panelGrid>
</p:dialog>
</h:form>
TableBean.java
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.UUID;
import org.primefaces.examples.domain.Car;
public class TableBean {
static {
colors = new String[10];
colors[0] = "Black";
colors[1] = "White";
colors[2] = "Green";
colors[3] = "Red";
colors[4] = "Blue";
colors[5] = "Orange";
colors[6] = "Silver";
colors[7] = "Yellow";
colors[8] = "Brown";
colors[9] = "Maroon";
manufacturers = new String[10];
manufacturers[0] = "Mercedes";
manufacturers[1] = "BMW";
manufacturers[2] = "Volvo";
manufacturers[3] = "Audi";
manufacturers[4] = "Renault";
manufacturers[5] = "Opel";
manufacturers[6] = "Volkswagen";
manufacturers[7] = "Chrysler";
manufacturers[8] = "Ferrari";
manufacturers[9] = "Ford";
}
private final static String[] colors;
private final static String[] manufacturers;
private List<Car> cars;
private Car selectedCar;
public TableBean() {
cars = new ArrayList<Car>();
populateRandomCars(cars, 50);
}
private void populateRandomCars(List<Car> list, int size) {
for(int i = 0 ; i < size ; i++)
list.add(new Car(getRandomModel(), getRandomYear(), getRandomManufacturer(), getRandomColor()));
}
public Car getSelectedCar() {
return selectedCar;
}
public void setSelectedCar(Car selectedCar) {
this.selectedCar = selectedCar;
}
public List<Car> getCars() {
return cars;
}
private int getRandomYear() {
return (int) (Math.random() * 50 + 1960);
}
private String getRandomColor() {
return colors[(int) (Math.random() * 10)];
}
private String getRandomManufacturer() {
return manufacturers[(int) (Math.random() * 10)];
}
private String getRandomModel() {
return UUID.randomUUID().toString().substring(0, 8);
}
}
例外是：
WARNING: datatableRowSelection.xhtml value="#{tableBean.selectedCar.model}": Target Unreachable, 'selectedCar' returned null
javax.el.PropertyNotFoundException: datatableRowSelection.xhtml value="#{tableBean.selectedCar.model}": Target Unreachable, 'selectedCar' returned null
at com.sun.faces.facelets.el.TagValueExpression.getType(TagValueExpression.java:100)
at com.sun.faces.renderkit.html_basic.HtmlBasicInputRenderer.getConvertedValue(HtmlBasicInputRenderer.java:95)
at javax.faces.component.UIInput.getConvertedValue(UIInput.java:1034)
at javax.faces.component.UIInput.validate(UIInput.java:964)
at javax.faces.component.UIInput.executeValidate(UIInput.java:1237)
at javax.faces.component.UIInput.processValidators(UIInput.java:702)
at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1220)
at com.sun.faces.context.PartialViewContextImpl$PhaseAwareVisitCallback.visit(PartialViewContextImpl.java:506)
at com.sun.faces.component.visit.PartialVisitContext.invokeVisitCallback(PartialVisitContext.java:183)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1612)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1623)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1623)
at javax.faces.component.UIForm.visitTree(UIForm.java:371)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1623)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1623)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1623)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1623)
at com.sun.faces.context.PartialViewContextImpl.processComponents(PartialViewContextImpl.java:378)
at com.sun.faces.context.PartialViewContextImpl.processPartial(PartialViewContextImpl.java:253)
at javax.faces.context.PartialViewContextWrapper.processPartial(PartialViewContextWrapper.java:183)
at javax.faces.component.UIViewRoot.processValidators(UIViewRoot.java:1162)
at com.sun.faces.lifecycle.ProcessValidationsPhase.execute(ProcessValidationsPhase.java:76)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:118)
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:84)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:113)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:103)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:113)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:45)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
at org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilter(BasicAuthenticationFilter.java:150)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
at org.springframework.security.web.authentication.ui.DefaultLoginPageGeneratingFilter.doFilter(DefaultLoginPageGeneratingFilter.java:91)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:183)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:87)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:192)
at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:160)
at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)
at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:936)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
你能告诉我为什么吗？非常感谢