when getting started on xxl-job today, use idea to import the project and build maven projects. To start the project with the Maven plugin, configure Run after you finish.

reports the following error:

[INFO] --- tomcat7-maven-plugin:2.2:run (default-cli) @ xxl-job-admin ---
[INFO] Running war on http://localhost:8080/xxl-job-admin
[INFO] Using existing Tomcat server configuration at D:\xxl-job-1.9.1\xxl-job-admin\target\tomcat
[INFO] create webapp with contextPath: /xxl-job-admin
九月 03, 2018 4:39:42 下午 org.apache.coyote.AbstractProtocol init
信息: Initializing ProtocolHandler ["http-bio-8080"]
九月 03, 2018 4:39:42 下午 org.apache.catalina.core.StandardService startInternal
信息: Starting service Tomcat
九月 03, 2018 4:39:42 下午 org.apache.catalina.core.StandardEngine startInternal
信息: Starting Servlet Engine: Apache Tomcat/7.0.47
九月 03, 2018 4:39:42 下午 org.apache.catalina.core.ContainerBase startInternal
严重: A child container failed during start
java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Tomcat].StandardHost[localhost].StandardContext[/xxl-job-admin]]
	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:1123)
	at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:800)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
	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[Tomcat].StandardHost[localhost].StandardContext[/xxl-job-admin]]
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
	... 6 more
Caused by: java.lang.ClassCastException: org.springframework.web.SpringServletContainerInitializer cannot be cast to javax.servlet.ServletContainerInitializer
	at org.apache.catalina.startup.ContextConfig.getServletContainerInitializer(ContextConfig.java:1670)
	at org.apache.catalina.startup.ContextConfig.getServletContainerInitializers(ContextConfig.java:1652)
	at org.apache.catalina.startup.ContextConfig.processServletContainerInitializers(ContextConfig.java:1562)
	at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1270)
	at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:878)
	at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:376)
	at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
	at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
	at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5322)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	... 6 more

九月 03, 2018 4:39:42 下午 org.apache.catalina.core.ContainerBase startInternal
严重: A child container failed during start
java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Tomcat].StandardHost[localhost]]
	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:1123)
	at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:302)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	at org.apache.catalina.core.StandardService.startInternal(StandardService.java:443)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:732)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	at org.apache.catalina.startup.Tomcat.start(Tomcat.java:341)
	at org.apache.tomcat.maven.plugin.tomcat7.run.AbstractRunMojo.startContainer(AbstractRunMojo.java:1238)
	at org.apache.tomcat.maven.plugin.tomcat7.run.AbstractRunMojo.execute(AbstractRunMojo.java:592)
	at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:137)
	at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:208)
	at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:154)
	at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:146)
	at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:117)
	at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:81)
	at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:56)
	at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
	at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:305)
	at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:192)
	at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:105)
	at org.apache.maven.cli.MavenCli.execute(MavenCli.java:956)
	at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:290)
	at org.apache.maven.cli.MavenCli.main(MavenCli.java:194)
	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:497)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
	at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
	at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
	at org.codehaus.classworlds.Launcher.main(Launcher.java:47)
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Tomcat].StandardHost[localhost]]
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
	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: A child container failed during start
	at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1131)
	at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:800)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	... 6 more

[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 3.579 s
[INFO] Finished at: 2018-09-03T16:39:42+08:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.tomcat.maven:tomcat7-maven-plugin:2.2:run (default-cli) on project xxl-job-admin: Could not start Tomcat: Failed to start component [StandardServer[-1]]: Failed to start component [StandardService[Tomcat]]: Failed to start component [StandardEngine[Tomcat]]: A child container failed during start -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException

Process finished with exit code 1

but can only use local Tomcat run, and then look up the Internet. Found the problem:

1. The servlet version that might be introduced is too high, such as version 3.1 that is compatible with the Tomcat7 plug-in, and you can try to downgrade 3.0.1. Can be introduced with reference to the official form: http://tomcat.apache.org/whichversion.html. Then I went this way and found it didn’t work. Because the current version of the project USES 3.0.1)

2, may is web. The XML version of the head is too high, can try to modify into: * * * * http://java.sun.com/xml/ns/javaee/ “id =” WebApp_ID “version =” 2.5 “& gt; **** or 2.4. (this doesn’t seem to work either, because it’s 2.5

)

3, but observation error on the reasons, problems in: org. Springframework. Web. SpringServletContainerInitializer always be cast to javax.mail. Servlet. ServletContainerInitializer, meaning to the servlet API. The jar package caused by the conflict. You can try to exclude the Commons-Logging.jar package because servlet-apy.jar is introduced in Commons-logging.2.3.

() never tried

4. Try to add scope plus provided, that is, change the scope to be used when compiling, but you don’t need to bring:

for packaging

works.

I only tried the fourth one, and I solved the problem. And then I didn’t try any more.