项目启动时抱错

wwwbird

[ERROR] [org.hibernate.engine.jdbc.spi.SqlExceptionHelper:144] Communications link failure

[ERROR] [org.hibernate.engine.jdbc.spi.SqlExceptionHelper:144] connection holder is null

[ERROR] [org.jeecgframework.core.common.exception.GlobalExceptionResolver:86] 全局处理异常捕获:

项目启动时,报这些错误,是哪里的问题?请大神赐教......多谢多谢.