遇到的問題如下：
java.lang.ClassNotFoundException: org.apache.catalina.servlet4preview.http.HttpServletRequest
	at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1928)
	at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1771)
	at java.lang.Class.getDeclaredMethods0(Native Method)
	at java.lang.Class.privateGetDeclaredMethods(Unknown Source)
	at java.lang.Class.getDeclaredMethods(Unknown Source)
	at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.buildLifecycleMetadata(InitDestroyAnnotationBeanPostProcessor.java:199)
	at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.findLifecycleMetadata(InitDestroyAnnotationBeanPostProcessor.java:181)
	at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessMergedBeanDefinition(InitDestroyAnnotationBeanPostProcessor.java:124)
	at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessMergedBeanDefinition(CommonAnnotationBeanPostProcessor.java:281)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyMergedBeanDefinitionPostProcessors(AbstractAutowireCapableBeanFactory.java:908)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:512)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
	at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:700)
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
	at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:643)
	at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:606)
	at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:657)
	at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:525)
	at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:466)
	at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
	at javax.servlet.GenericServlet.init(GenericServlet.java:158)
	at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1230)
	at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1174)
	at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:847)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:135)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:498)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:1025)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445)
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1139)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637)
	at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Unknown Source)

　　最後發現是將HttpServletRequest導錯了，只要將導的包改成import javax.servlet.http.HttpServletRequest就可以了

java.lang.ClassNotFoundException: org.apache.catalina.servlet4preview.http.HttpServletRequest