几天在GitHub上查找了erp的系统，但在使用时遇到下面这个问题
Caused by: java.lang.NullPointerException: Cannot invoke "java.util.Map.get(Object)" because "this.serverVariables" is null
at com.mysql.jdbc.ConnectionImpl.getServerCharset(ConnectionImpl.java:3299)
at com.mysql.jdbc.MysqlIO.sendConnectionAttributes(MysqlIO.java:1967)
at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1893)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1287)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2494)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2527)
... 143 more