tomcat启动报错Caused by: java.lang.IllegalArgumentException: The main resource set specifiedis not valid

原因：笔者电脑中不存在“G:\Tomcatdata\data\sourcecode\chapter03\helloapp]”此路径、文件，所以删除tomcat文件目录下的conf\server.xml文件中的对应信息（Context）后，tomcat能正常启动。

错误信息如下：

07-Dec-2018 20:16:43.535 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Server version:        Apache Tomcat/9.0.5
07-Dec-2018 20:16:43.540 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Server built:          Feb 6 2018 21:42:23 UTC
07-Dec-2018 20:16:43.540 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Server number:         9.0.5.0
07-Dec-2018 20:16:43.540 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log OS Name:               Windows 10
07-Dec-2018 20:16:43.541 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log OS Version:            10.0
07-Dec-2018 20:16:43.541 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Architecture:          amd64
07-Dec-2018 20:16:43.542 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Java Home:             C:\Program Files\Java\jdk1.8.0_112\jre
07-Dec-2018 20:16:43.542 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Version:           1.8.0_112-b15
07-Dec-2018 20:16:43.547 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Vendor:            Oracle Corporation
07-Dec-2018 20:16:43.547 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_BASE:         E:\tomcat9.0\tomcat9.0
07-Dec-2018 20:16:43.547 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_HOME:         E:\tomcat9.0\tomcat9.0
07-Dec-2018 20:16:43.547 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.config.file=E:\tomcat9.0\tomcat9.0\conf\logging.properties
07-Dec-2018 20:16:43.548 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
07-Dec-2018 20:16:43.548 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djdk.tls.ephemeralDHKeySize=2048
07-Dec-2018 20:16:43.548 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.protocol.handler.pkgs=org.apache.catalina.webresources
07-Dec-2018 20:16:43.552 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dignore.endorsed.dirs=
07-Dec-2018 20:16:43.552 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.base=E:\tomcat9.0\tomcat9.0
07-Dec-2018 20:16:43.555 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.home=E:\tomcat9.0\tomcat9.0
07-Dec-2018 20:16:43.555 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.io.tmpdir=E:\tomcat9.0\tomcat9.0\temp
07-Dec-2018 20:16:43.556 信息 [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: [C:\Program Files\Java\jdk1.8.0_112\bin;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;E:\oracle_XE\app\oracle\product\11.2.0\server\bin;C:\Program Files (x86)\Common Files\Intel\Shared Files\cpp\bin\Intel64;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;C:\Program Files\Intel\WiFi\bin\;C:\Program Files\Common Files\Intel\WirelessCommon\;E:\MATLAB\runtime\win64;E:\MATLAB\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\Program Files\MySQL\MySQL Server 5.7\bin;C:\Program Files (x86)\GtkSharp\2.12\bin;C:\Program Files\Java\jdk1.8.0_112\jre\bin;C:\Program Files\Java\jdk1.8.0_112\bin;E:\oracle_XE\app\oracle\product\11.2.0\server\bin;E:\python\Scripts\;E:\python\;C:\Users\黄建业\AppData\Local\Microsoft\WindowsApps;E:\JavaEE_7_src\JavaEE_7\JavaEE_7;;.]
07-Dec-2018 20:16:43.697 信息 [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["http-nio-80"]
07-Dec-2018 20:16:43.893 信息 [main] org.apache.tomcat.util.net.NioSelectorPool.getSharedSelector Using a shared selector for servlet write/read
07-Dec-2018 20:16:43.909 信息 [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["ajp-nio-8009"]
07-Dec-2018 20:16:43.914 信息 [main] org.apache.tomcat.util.net.NioSelectorPool.getSharedSelector Using a shared selector for servlet write/read
07-Dec-2018 20:16:43.916 信息 [main] org.apache.catalina.startup.Catalina.load Initialization processed in 894 ms
07-Dec-2018 20:16:43.978 信息 [main] org.apache.catalina.core.StandardService.startInternal Starting service [Catalina]
07-Dec-2018 20:16:43.979 信息 [main] org.apache.catalina.core.StandardEngine.startInternal Starting Servlet Engine: Apache Tomcat/9.0.5
07-Dec-2018 20:16:44.021 严重 [main] org.apache.catalina.core.ContainerBase.startInternal A child container failed during start
 java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [org.apache.catalina.webresources.StandardRoot@2353b3e6]
	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:947)
	at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:839)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1425)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1415)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
	at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134)
	at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:941)
	at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:258)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
	at org.apache.catalina.core.StandardService.startInternal(StandardService.java:422)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
	at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:770)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:682)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:353)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:493)
Caused by: org.apache.catalina.LifecycleException: Failed to start component [org.apache.catalina.webresources.StandardRoot@2353b3e6]
	at org.apache.catalina.util.LifecycleBase.handleSubClassException(LifecycleBase.java:441)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:198)
	at org.apache.catalina.core.StandardContext.resourcesStart(StandardContext.java:4752)
	at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:4887)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1425)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1415)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
	at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134)
	at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:941)
	... 21 more
Caused by: java.lang.IllegalArgumentException: The main resource set specified [G:\Tomcatdata\data\sourcecode\chapter03\helloapp] is not valid
	at org.apache.catalina.webresources.StandardRoot.createMainResourceSet(StandardRoot.java:749)
	at org.apache.catalina.webresources.StandardRoot.startInternal(StandardRoot.java:706)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
	... 30 more

07-Dec-2018 20:16:44.023 严重 [main] org.apache.catalina.core.ContainerBase.startInternal A child container failed during start
 java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: A child container failed during start
	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:947)
	at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:258)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
	at org.apache.catalina.core.StandardService.startInternal(StandardService.java:422)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
	at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:770)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:682)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:353)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:493)
Caused by: org.apache.catalina.LifecycleException: A child container failed during start
	at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:956)
	at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:839)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1425)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1415)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
	at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134)
	at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:941)
	... 13 more

07-Dec-2018 20:16:44.031 严重 [main] org.apache.catalina.startup.Catalina.start The required Server component failed to start so Tomcat is unable to start.
 org.apache.catalina.LifecycleException: A child container failed during start
	at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:956)
	at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:258)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
	at org.apache.catalina.core.StandardService.startInternal(StandardService.java:422)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
	at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:770)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:682)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:353)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:493)

07-Dec-2018 20:16:44.033 信息 [main] org.apache.coyote.AbstractProtocol.pause Pausing ProtocolHandler ["http-nio-80"]
07-Dec-2018 20:16:44.034 信息 [main] org.apache.coyote.AbstractProtocol.pause Pausing ProtocolHandler ["ajp-nio-8009"]
07-Dec-2018 20:16:44.035 信息 [main] org.apache.catalina.core.StandardService.stopInternal Stopping service [Catalina]
07-Dec-2018 20:16:44.037 信息 [main] org.apache.coyote.AbstractProtocol.destroy Destroying ProtocolHandler ["http-nio-80"]
07-Dec-2018 20:16:44.040 信息 [main] org.apache.coyote.AbstractProtocol.destroy Destroying ProtocolHandler ["ajp-nio-8009"]