MySQL解決中文亂碼之全套方案

今天遇到一堆MySQL 中文亂碼的問題，總體來說分爲數據庫層面，Tomcat層面，web表示層面。

數據庫層面

先是MySQL數據庫中文亂碼問題，大概樣子如下：

然後自我感覺這件事情不就是改下字段的編碼嗎，那就改一下唄
如圖，我更改了Encoding

然後發現事情並沒有那簡單，於是開始上網查解決方案，網上說需要修改/etc/my.cnf(此配置文件對於mac後綴是.cnf，對於Windows是.ini)。所以漫漫找尋之路開始了，最後連Linux查詢find語句也試了就是找不到，終於在幾篇文章裏查到Mac上的MySQL沒有my.cnf配置文件，好吧，繼續尋找解決方案，有人說MySQL下的support-file中找一個.cnf複製一下再改；裏面的東西，然而我連.cnf文件都沒有找到。最後採用一位網友的辦法，直接在/etc目錄下 vim my.cnf新建一個文件，在此附上我修改過的文件裏面內容，在[mysqld] 之後增加了一行 collation-server = utf8_general_ci


# Example MySQL config file for medium systems.
  #
  # This is for a system with little memory (32M - 64M) where MySQL plays
  # an important part, or systems up to 128M where MySQL is used together with
  # other programs (such as a web server)
  #
  # MySQL programs look for option files in a set of
  # locations which depend on the deployment platform.
  # You can copy this option file to one of those
  # locations. For information about these locations, see:
  # http://dev.mysql.com/doc/mysql/en/option-files.html
  #
  # In this file, you can use all long options that a program supports.
  # If you want to know which options a program supports, run the program
  # with the "--help" option.
  # The following options will be passed to all MySQL clients
  [client]
  default-character-set=utf8
  #password   = your_password
  port        = 3306
  socket      = /tmp/mysql.sock
  # Here follows entries for some specific programs
  # The MySQL server
  [mysqld]
  character-set-server=utf8
  default-storage-engine = INNODB
  collation-server = utf8_general_ci
  init_connect='SET NAMES utf8'
  port        = 3306
  socket      = /tmp/mysql.sock
  skip-external-locking
  key_buffer_size = 16M
  max_allowed_packet = 1M
  table_open_cache = 64
  sort_buffer_size = 512K
  net_buffer_length = 8K
  read_buffer_size = 256K
  read_rnd_buffer_size = 512K
  myisam_sort_buffer_size = 8M
  character-set-server=utf8
  init_connect='SET NAMES utf8'
# Don't listen on a TCP/IP port at all. This can be a security enhancement,
# if all processes that need to connect to mysqld run on the same host.
# All interaction with mysqld must be made via Unix sockets or named pipes.
# Note that using this option without enabling named pipes on Windows
# (via the "enable-named-pipe" option) will render mysqld useless!
#
#skip-networking

  # Replication Master Server (default)
  # binary logging is required for replication
  log-bin=mysql-bin

    # binary logging format - mixed recommended
    binlog_format=mixed

      # required unique id between 1 and 2^32 - 1
      # defaults to 1 if master-host is not set
      # but will not function as a master if omitted
      server-id   = 1

    # Replication Slave (comment out master section to use this)
    #
    # To configure this host as a replication slave, you can choose between
    # two methods :
    #
    # 1) Use the CHANGE MASTER TO command (fully described in our manual) -
    #    the syntax is:
    #
    #    CHANGE MASTER TO MASTER_HOST=<host>, MASTER_PORT=<port>,
    #    MASTER_USER=<user>, MASTER_PASSWORD=<password> ;
    #
    #    where you replace <host>, <user>, <password> by quoted strings and
    #    <port> by the master's port number (3306 by default).
    #
    #    Example:
    #
    #    CHANGE MASTER TO MASTER_HOST='125.564.12.1', MASTER_PORT=3306,
    #    MASTER_USER='joe', MASTER_PASSWORD='secret';
    #
    # OR
    #
    # 2) Set the variables below. However, in case you choose this method, then
    #    start replication for the first time (even unsuccessfully, for example
    #    if you mistyped the password in master-password and the slave fails to
    #    connect), the slave will create a master.info file, and any later
    #    change in this file to the variables' values below will be ignored and
    #    overridden by the content of the master.info file, unless you shutdown
    #    the slave server, delete master.info and restart the slaver server.
    #    For that reason, you may want to leave the lines below untouched
    #    (commented) and instead use CHANGE MASTER TO (see above)
    #
    # required unique id between 2 and 2^32 - 1
    # (and different from the master)
    # defaults to 2 if master-host is set
    # but will not function as a slave if omitted
    #server-id       = 2
    #
    # The replication master for this slave - required
    #master-host     =   <hostname>
    #
    # The username the slave will use for authentication when connecting
    # to the master - required
    #master-user     =   <username>
    #
    # The password the slave will authenticate with when connecting to
    # the master - required
    #master-password =   <password>
    #
    # The port the master is listening on.
    # optional - defaults to 3306
    #master-port     =  <port>
    #
    # binary logging - not required for slaves, but recommended
    #log-bin=mysql-bin

      # Uncomment the following if you are using InnoDB tables
      #innodb_data_home_dir = /usr/local/mysql/data
      #innodb_data_file_path = ibdata1:10M:autoextend
      #innodb_log_group_home_dir = /usr/local/mysql/data
      # You can set .._buffer_pool_size up to 50 - 80 %
      # of RAM but beware of setting memory usage too high
      #innodb_buffer_pool_size = 16M
      #innodb_additional_mem_pool_size = 2M
      # Set .._log_file_size to 25 % of buffer pool size
      #innodb_log_file_size = 5M
      #innodb_log_buffer_size = 8M
      #innodb_flush_log_at_trx_commit = 1
      #innodb_lock_wait_timeout = 50

        [mysqldump]
        quick
        max_allowed_packet = 16M

          [mysql]
          no-auto-rehash
          # Remove the next comment character if you are not familiar with SQL
          #safe-updates
          default-character-set=utf8

        [myisamchk]
        key_buffer_size = 20M
        sort_buffer_size = 20M
        read_buffer = 2M
        write_buffer = 2M

          [mysqlhotcopy]
          interactive-timeout

此時保存文件，再修改文件讀寫權限，將權限修改爲664

sudo chmod 664 /etc/my.cnf

之後再重啓MySQL和配置文件就可以生效了。
然後完成之後，確實，如果你查一下MySQL的各種編碼，確實都變成了UTF-8
通過以下命令

然而~輸入不了中文了，報錯

最後將當前數據庫以及所有表所有字段都設置爲UTF-8

驚喜的發現可以愉快的輸入中文了~~
至此，數據庫層面告一段落

Tomcat層面

接下來我說的簡略一些，如果URL請求採取GET方法，那麼你的URL中可能會出現中文，所以需要在Tomcat配置文件裏面設置編碼方式。

修改Tomcat下的conf/server.xml文件，找到如下代碼：

 <Connector port="8080" protocol="HTTP/1.1"
               connectionTimeout="20000"
               redirectPort="8443" />

這段代碼規定了Tomcat監聽HTTP請求的端口號等信息。可以在這裏添加一個屬性：URIEncoding，將該屬性值設置爲UTF-8，
即可讓Tomcat（默認ISO-8859-1編碼）以UTF-8的編碼處理get請求。更改後的代碼如下所示：

<Connector port="8080" protocol="HTTP/1.1"
               connectionTimeout="20000"
              URIEncoding="UTF-8"
               redirectPort="8443" />

Web顯示層面

這裏主要針對請求爲POST方法的時候，你需要設置web.xml 文件，設置字符串過濾器

<filter>
   <filter-name>characterEncodingFilter</filter-name>
   <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
   <init-param>
       <param-name>encoding</param-name>
       <param-value>UTF-8</param-value>
   </init-param>
   <init-param>
       <param-name>forceEncoding</param-name>
       <param-value>true</param-value>
   </init-param>
</filter>
<filter-mapping>
   <filter-name>characterEncodingFilter</filter-name>
   <url-pattern>/*</url-pattern>
</filter-mapping>

最後如果你要回顯到頁面上打印中文的話需要設置一下response
如果你使用springMVC可以設置

@RequestMapping(value = "/XX.do", produces="text/html;charset=UTF-8")

MySQL解決中文亂碼之全套方案

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Web顯示層面

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