eclipse web项目缺少tomcat lib的解决

1、我用的是eclipse4.5,创建好maven管理的web 项目后，发现Java build path的Libraries缺少tomcat lib，如下图

2、选中项目–右键属性–projects facets
选择web版本，Java版本最终要的是在窗口右面的Runtimes选项里勾选对应tomcat版本，我这里用的是tomcat8，最后记得点击apply按钮

3、如下图，tomcat lib在Libraries里面了

如果没有tomcat lib你很可能因缺少tomcat中的lib报如下错误

严重: StandardWrapper.Throwablejava.lang.NoClassDefFoundError: HttpServletRequest    at java.lang.Class.getDeclaredMethods0(Native Method)    at java.lang.Class.privateGetDeclaredMethods(Class.java:2701)    at java.lang.Class.getDeclaredMethods(Class.java:1975)    at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:571)    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:488)    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:501)    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:474)    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.determineCandidateConstructors(AutowiredAnnotationBeanPostProcessor.java:241)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineConstructorsFromBeanPostProcessors(AbstractAutowireCapableBeanFactory.java:1065)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1038)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)    at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:663)    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:629)    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:677)    at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:548)    at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:489)    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:1231)    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1144)    at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1031)    at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4914)    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5201)    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1408)    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1398)    at java.util.concurrent.FutureTask.run(FutureTask.java:266)    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)    at java.lang.Thread.run(Thread.java:745)Caused by: java.lang.ClassNotFoundException: HttpServletRequest    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1332)    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1166)    ... 38 more二月 22, 2016 8:55:50 下午 org.apache.catalina.core.StandardContext loadOnStartup严重: Servlet [springMVC] in web application [/hgbj] threw load() exceptionjava.lang.ClassNotFoundException: HttpServletRequest    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1332)    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1166)    at java.lang.Class.getDeclaredMethods0(Native Method)    at java.lang.Class.privateGetDeclaredMethods(Class.java:2701)    at java.lang.Class.getDeclaredMethods(Class.java:1975)    at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:571)    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:488)    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:501)    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:474)    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.determineCandidateConstructors(AutowiredAnnotationBeanPostProcessor.java:241)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineConstructorsFromBeanPostProcessors(AbstractAutowireCapableBeanFactory.java:1065)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1038)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)    at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:663)    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:629)    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:677)    at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:548)    at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:489)    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:1231)    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1144)    at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1031)    at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4914)    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5201)    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1408)    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1398)    at java.util.concurrent.FutureTask.run(FutureTask.java:266)    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)    at java.lang.Thread.run(Thread.java:745)二月 22, 2016 8:55:50 下午 org.apache.coyote.AbstractProtocol start信息: Starting ProtocolHandler ["http-nio-8080"]二月 22, 2016 8:55:50 下午 org.apache.coyote.AbstractProtocol start信息: Starting ProtocolHandler ["ajp-nio-8009"]二月 22, 2016 8:55:50 下午 org.apache.catalina.startup.Catalina start信息: Server startup in 3600 ms二月 22, 2016 8:55:51 下午 org.apache.catalina.core.ApplicationContext log信息: Initializing Spring FrameworkServlet 'springMVC'二月 22, 2016 8:55:51 下午 org.apache.catalina.core.ApplicationContext log严重: StandardWrapper.Throwablejava.lang.NoClassDefFoundError: HttpServletRequest    at java.lang.Class.getDeclaredMethods0(Native Method)    at java.lang.Class.privateGetDeclaredMethods(Class.java:2701)    at java.lang.Class.getDeclaredMethods(Class.java:1975)    at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:571)    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:488)    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:501)    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:474)    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.determineCandidateConstructors(AutowiredAnnotationBeanPostProcessor.java:241)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineConstructorsFromBeanPostProcessors(AbstractAutowireCapableBeanFactory.java:1065)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1038)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)    at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:663)    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:629)    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:677)    at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:548)    at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:489)    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:1231)    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1144)    at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:817)    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:135)    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673)    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1526)    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1482)    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)    at java.lang.Thread.run(Thread.java:745)Caused by: java.lang.ClassNotFoundException: HttpServletRequest    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1332)    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1166)    ... 45 more二月 22, 2016 8:55:51 下午 org.apache.catalina.core.StandardWrapperValve invoke严重: Allocate exception for servlet springMVCjava.lang.ClassNotFoundException: HttpServletRequest    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1332)    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1166)    at java.lang.Class.getDeclaredMethods0(Native Method)    at java.lang.Class.privateGetDeclaredMethods(Class.java:2701)    at java.lang.Class.getDeclaredMethods(Class.java:1975)    at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:571)    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:488)    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:501)    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:474)    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.determineCandidateConstructors(AutowiredAnnotationBeanPostProcessor.java:241)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineConstructorsFromBeanPostProcessors(AbstractAutowireCapableBeanFactory.java:1065)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1038)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)    at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:663)    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:629)    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:677)    at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:548)    at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:489)    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:1231)    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1144)    at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:817)    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:135)    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673)    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1526)    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1482)    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)    at java.lang.Thread.run(Thread.java:745)