我当前正在为学校的动态Web项目工作，我遇到了一个奇怪的问题...我正在尝试从.jsp文件运行servlet。我做了很多研究，显然（如果我错了，请纠正我！），如果要在.jsp文件中使用它们，则需要将编译后的Servlet或Java类文件放入Web-Inf/class Directory中。
将构建路径设置为该目录甚至创建目录之前，我能够运行我的Web应用程序。我对构建路径进行了更改的第二个，我的服务器拒绝启动，现在我遇到了此错误：
SEVERE: A child container failed during start
java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/PullUp]]
at java.util.concurrent.FutureTask.report(FutureTask.java:122)
at java.util.concurrent.FutureTask.get(FutureTask.java:192)
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:915)
at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:871)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1407)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1397)
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: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/PullUp]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:162)
... 6 more
Caused by: java.lang.IllegalArgumentException: The servlets named [ListingServlet] and [com.pullup.ListingServlet] are both mapped to the url-pattern [/ListingServlet] which is not permitted
at org.apache.tomcat.util.descriptor.web.WebXml.addServletMappingDecoded(WebXml.java:316)
at org.apache.tomcat.util.descriptor.web.WebXml.addServletMapping(WebXml.java:309)
at org.apache.catalina.startup.ContextConfig.processAnnotationWebServlet(ContextConfig.java:2384)
at org.apache.catalina.startup.ContextConfig.processAnnotationsStream(ContextConfig.java:2066)
at org.apache.catalina.startup.ContextConfig.processAnnotationsWebResource(ContextConfig.java:1951)
at org.apache.catalina.startup.ContextConfig.processAnnotationsWebResource(ContextConfig.java:1945)
at org.apache.catalina.startup.ContextConfig.processAnnotationsWebResource(ContextConfig.java:1945)
at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1156)
at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:783)
at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:307)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:95)
at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5213)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
... 6 more
有人对如何解决这个问题有任何想法吗？任何帮助将不胜感激！
您正在获得均映射到url-Pattern 例外，因为当Tomcat试图加载servlet类时，它已经找到了2个映射的同一servlet。，一个来自web.xml，另一个来自@webservlet。
@webservlet是一种替代方法（在Javaee6容器中）来定义Servlet URL映射（内联servlet源代码）。因此，您不应该添加这些servlet并映射到web.xml（即，只需从Web-Inf文件夹中删除Web.xml）。