JDBC连接MySQL数据入库，中文出现乱码，在客户端插入中文数据都正常。JDBC设置编码为UTF-8问题依然存在，就可以确定是由于MySQL服务的默认编码不为UTF-8引起的。
1、检查默认安装的MySQL的字符集
mysql> show variables like '%char%';
+--------------------------+----------------------------
| Variable_name | Value
+--------------------------+----------------------------
| character_set_client | utf8
| character_set_connection | utf8
| character_set_database | utf8
| character_set_filesystem | binary
| character_set_results | utf8
| character_set_server | latin1
| character_set_system | utf8
| character_sets_dir | /usr/local/mysql-5.6.19-osx10.7-x86/share/charsets/ |
+--------------------------+----------------------------
8 rows in set (0.02 sec)
character_set_server是latin1字符集，客户端与服务端的字符集不一致引起了中文乱码。要修改默认字符集，要修改my.cnf，在修改my.cnf之前一定要关闭mysql进程，不然会遇到MySQL的sock不能连接的问题。
2、关闭MySQL后台进程
在系统偏好设置里面控制MySQL，直接点击”Stop MySQL Server”就行了； 也可以找到MySQL所在的位置，/usr/local/mysql/bin,执行关闭命令。
3、修改MySQL配置文件/etc/my.cnf
sudo cp /usr/local/mysql/support-files/my-medium.cnf /etc/my.cnf
sudo vi /etc/my.cnf
[client]部分加入： default-character-server = utf8
4、检查结果
mysql> show variables like '%char%';
+--------------------------+----------------------
| Variable_name | Value
+--------------------------+----------------------
| character_set_client | utf8
| character_set_connection | utf8
| character_set_database | utf8
| character_set_filesystem | binary
| character_set_results | utf8
| character_set_server | utf8
| character_set_system | utf8
| character_sets_dir | /usr/local/mysql-5.6.19-osx10.7-x86/share/charsets/ |
+--------------------------+-----------------------
8 rows in set (0.01 sec)
所有的编码已经更改为UTF-8字符集。
