我想将Ajax和Apache Tiles与Spring Web Fow集成。没有Tiles的简单流程工作正常，但在与Tiles集成后抛出NullPointerException。
这是Web Flow servlet：
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:webflow="http://www.springframework.org/schema/webflow-config"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
http://www.springframework.org/schema/webflow-config
http://www.springframework.org/schema/webflow-config/spring-webflow-config-2.3.xsd">
<bean id="transportWebFlow" class="com.demo.controller.DemoController"/>
<bean id="tilesViewResolver" class="org.springframework.web.servlet.view.UrlBasedViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.tiles2.TilesView" />
<!-- <property name="prefix" value="/WEB-INF/jsp/"/>
<property name="suffix" value=".jsp"/> -->
</bean>
<!-- <bean id="tilesViewResolver" class="org.springframework.js.ajax.AjaxUrlBasedViewResolver">
<property name="viewClass" value="org.springframework.webflow.mvc.view.FlowAjaxTilesView"/>
</bean> -->
<bean class="org.springframework.web.servlet.view.tiles2.TilesConfigurer">
<property name="definitions">
<list>
<value>/WEB-INF/tilesDefination/demo.xml</value>
</list>
</property>
</bean>
<bean id="handlerMapping" class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
<property name="mappings">
<value>/*.html=flowController</value>
</property>
</bean>
<bean id="flowController" class="org.springframework.webflow.mvc.servlet.FlowController">
<property name="flowExecutor" ref="flowExecutor"/>
</bean>
<webflow:flow-executor id="flowExecutor" flow-registry="flowRegistry">
</webflow:flow-executor>
<webflow:flow-registry id="flowRegistry" base-path="/WEB-INF/flows/" flow-builder-services="flowBuilderServices">
<webflow:flow-location id="demo" path="demo-flow.xml" />
</webflow:flow-registry>
<webflow:flow-builder-services id="flowBuilderServices"
view-factory-creator="viewFactoryCreator" development="true"/>
<bean id="viewFactoryCreator" class="org.springframework.webflow.mvc.builder.MvcViewFactoryCreator">
<property name="viewResolvers" ref ="tilesViewResolver"/>
</bean>
</beans>
Webflow的磁贴配置
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE tiles-definitions PUBLIC "-//Apache Software Foundation//DTD Tiles Configuration 2.1//EN"
"http://tiles.apache.org/dtds/tiles-config_2_1.dtd">
<tiles-definitions>
<definition name="base.demo" template="/WEB-INF/jsp/demoLayout.jsp">
<put-attribute name="title" value="Travel.com"/>
<put-attribute name="demoHeader" value="/WEB-INF/jsp/demoHeader.jsp"/>
<put-attribute name="demoBody" value=""/>
<put-attribute name="demoFooter" value="/WEB-INF/jsp/demoFooter.jsp"/>
</definition>
<definition name="demo" extends="base.demo">
<put-attribute name="demoBody" value="/WEB-INF/jsp/demo.jsp"/>
</definition>
</tiles-definitions>
demo.xml
<?xml version="1.0" encoding="UTF-8"?>
<flow xmlns="http://www.springframework.org/schema/webflow"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="
http://www.springframework.org/schema/webflow
http://www.springframework.org/schema/webflow/spring-webflow-2.0.xsd">
<var name="demo" class="com.demo.model.Demo"/>
<view-state id="demo" view="/WEB-INF/jsp/demo.jsp" model="demo">
</view-state>
</flow>
控制器
package com.demo.controller;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;
import com.demo.model.Demo;
@Controller
public class DemoController {
@RequestMapping(value="demo.html",method=RequestMethod.GET)
public ModelAndView demo(){
Demo demo = new Demo();
return new ModelAndView("demo","demo", demo);
}
}
这是异常堆栈跟踪：
SEVERE: Servlet.service() for servlet [SpringFlow] in context with path [/DemoWebFlow] threw exception [Request processing failed; nested exception is org.springframework.webflow.execution.FlowExecutionException: Exception thrown in state 'demo' of flow 'demo'] with root cause
java.lang.NullPointerException
at org.springframework.webflow.mvc.servlet.ServletMvcView.doRender(ServletMvcView.java:50)
at org.springframework.webflow.mvc.view.AbstractMvcView.render(AbstractMvcView.java:187)
at org.springframework.webflow.engine.ViewState.render(ViewState.java:296)
at org.springframework.webflow.engine.ViewState.refresh(ViewState.java:243)
at org.springframework.webflow.engine.ViewState.resume(ViewState.java:221)
at org.springframework.webflow.engine.Flow.resume(Flow.java:545)
at org.springframework.webflow.engine.impl.FlowExecutionImpl.resume(FlowExecutionImpl.java:261)
at org.springframework.webflow.executor.FlowExecutorImpl.resumeExecution(FlowExecutorImpl.java:169)
at org.springframework.webflow.mvc.servlet.FlowHandlerAdapter.handle(FlowHandlerAdapter.java:183)
at org.springframework.webflow.mvc.servlet.FlowController.handleRequest(FlowController.java:174)
at org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter.handle(SimpleControllerHandlerAdapter.java:48)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:771)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:716)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:647)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:552)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
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:953)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1008)
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)