25-Feb-2019 10:22:36.459 严重 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Error deploying web application directory [E:\apache-tomcat-8.5.38-windows-x64\apache-tomcat-8.5.38\webapps\sy]
java.lang.IllegalStateException: ContainerBase.addChild: start: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/demo]]
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:758)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:730)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:734)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1140)
at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1875)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
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:748)

jar文件有问题,删掉,maven重新下载