错误提示： There are unfinished transactions remaining. You might consider running yum-complete-transacti...

方法一 A=123 echo "${A}" |[ -n "sed -n '/^[0-9][0-9]*$/p'" ] && echo ${A} is a numbers 方法二 A=12...

1、先把命令行切换到Maven项目的根目录，比如：/data/work/java/maven-test，然后执行命令：mvn clean package 执行命令成功后，生成好的war/jar包保存在...

1、启动MySQL失败 [root@localhost ~]# systemctl start mysqld Job for mysqld.service failed because the con...