java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start com

启动项目时报错 java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].

是由于@WebServlet(“show”)没写 / 改成@WebServlet("/show")即可