摘要：
启动SpringBoot项目时，会报告以下手册[boot.myboot.SampleController，boot.myboot.App]中的错误Unabletofindasinglemainclass。这意味着您无法从这两个类中找到要执行的main方法。执行spring引导：运行X打印调试日志[错误]Failedtoexecutegoal.org
在启动SpringBoot项目是报错
Unable to find a single main class from the following candidates[boot.myboot.SampleController, boot.myboot.App]
意思 是从这两个类中找不到要执行那个main方法
执行spring-boot：run -X打印出Debug日志
[ERROR] Failed to execute goal org.springframework.boot:spring-boot-maven-plugin:1.4.7.RELEASE:run (default-cli) on project myboot: Execution default-cli of goal org.springframework.boot:spring-boot-maven-plugin:1.4.7.RELEASE:run failed: Unable to find a single main class from the following candidates [boot.myboot.SampleController, boot.myboot.App] -> [Help 1] org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.springframework.boot:spring-boot-maven-plugin:1.4.7.RELEASE:run (default-cli) on project myboot: Execution default-cli of goal org.springframework.boot:spring-boot-maven-plugin:1.4.7.RELEASE:run failed: Unable to find a single main classfrom the following candidates [boot.myboot.SampleController, boot.myboot.App] at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:224) at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153) at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145) at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:116) at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:80) at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51) at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128) at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:307) at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:193) at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:106) at org.apache.maven.cli.MavenCli.execute(MavenCli.java:862) at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:286) at org.apache.maven.cli.MavenCli.main(MavenCli.java:197) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) 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) Caused by: org.apache.maven.plugin.PluginExecutionException: Execution default-cli of goal org.springframework.boot:spring-boot-maven-plugin:1.4.7.RELEASE:run failed: Unable to find a single main classfrom the following candidates [boot.myboot.SampleController, boot.myboot.App] at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:145) at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:208) ... 20more Caused by: java.lang.IllegalStateException: Unable to find a single main classfrom the following candidates [boot.myboot.SampleController, boot.myboot.App] at org.springframework.boot.loader.tools.MainClassFinder$MainClassesCallback.getMainClass(MainClassFinder.java:348) at org.springframework.boot.loader.tools.MainClassFinder.findSingleMainClass(MainClassFinder.java:99) at org.springframework.boot.maven.AbstractRunMojo.getStartClass(AbstractRunMojo.java:360) at org.springframework.boot.maven.AbstractRunMojo.execute(AbstractRunMojo.java:170) at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134) ... 21more [ERROR] [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/PluginExecutionException
错误原因是因为：在这两个类中都包含main方法，所以项目在运行时不知大概执行那个main方法开始项目
解决方法：两个类中的main方法只保留一个