SptingMVC+MyBatis登錄，自定義數據庫Utils類爆 NoClassDefFoundError

SptingMVC+MyBatis登錄demo

1、springMVC單獨和視圖交互傳遞數據測試通過；
2、MyBatis單獨測試數據交互獲取通過；
3、在整合使用時，瀏覽器發起請求，SpringMVC中的Control方法中接收數據，但是使用自定義的MyBatisUtils處理數據層dao時，前端接收500，返回如下錯誤：

HTTP Status 500 – Internal Server Error
Type 異常報告

消息 Handler dispatch failed; nested exception is java.lang.NoClassDefFoundError: Could not initialize class com.kunlun.chen.utils.MyBatisUtils

描述 服務器遇到一個意外的情況，阻止它完成請求。

Exception

org.springframework.web.util.NestedServletException: Handler dispatch failed; nested exception is java.lang.NoClassDefFoundError: Could not initialize class com.kunlun.chen.utils.MyBatisUtils
	org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1055)
	org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)
	org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
	org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:660)
	org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
Root Cause

java.lang.NoClassDefFoundError: Could not initialize class com.kunlun.chen.utils.MyBatisUtils
	com.kunlun.chen.utils.LoginDataHelper.squeryAllUser(LoginDataHelper.java:55)
	com.kunlun.chen.control.LoginControl.select(LoginControl.java:94)
	sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	java.lang.reflect.Method.invoke(Method.java:498)
	org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
	org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
	org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:106)
	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:888)
	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793)
	org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
	org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040)
	org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)
	org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
	org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:660)
	org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
Note 主要問題的全部 stack 信息可以在 server logs 裏查看

Apache Tomcat/8.5.47

解決方案：
cao 原來是包沒導入，截圖是導入後的，如果沒有導入過，會有很多，右鍵put進去