Failed to execute goal org.springframework.boot:spring-boot-maven-plugin:1.3.3.RELEASE:repackage (default) on project spring-boot-xjt: Execution default of goal org.springframework.boot:spring-boot-maven-plugin:1.3.3.RELEASE:repackage failed: Unable to find a single main class from the following candidates [com.xjt.Application, com.xjt.duaidi.KdniaoTrackQueryAPI, com.xjt.duaidi.Kuaidi100, com.xjt.test.Server2, com.xjt.test.Server3] -> [Help 1]

原因：查看这几个类，发现这几个类中确实均有一个main方法，去掉一个多余的main方法，保留唯一的main方法。