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准备搭建一个 Spring Boot 组合 mybatis 的项目，数据库采用的是 MySQL 8.0.11 按照以往的配置，使用插件 mybatis-generator-maven-plugin 生成代码时，一直报错 Could not create connection to database server. 如下：
[INFO] Scanning for projects…
[INFO]
[INFO] ————————————————————————
[INFO] Building songci-serv 1.0-SNAPSHOT
[INFO] ————————————————————————
[INFO]
[INFO] — mybatis-generator-maven-plugin:1.3.5:generate (default-cli) @ songci-serv —
[INFO] Connecting to the Database
[INFO] ————————————————————————
[INFO] BUILD FAILURE
[INFO] ————————————————————————
[INFO] Total time: 1.841 s
[INFO] Finished at: 2018-08-22T21:32:27+08:00
[INFO] Final Memory: 13M/46M
[INFO] ————————————————————————
[ERROR] Failed to execute goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.5:generate (default-cli) on project songci-serv: Could not create connection to database server. -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
经排查是，MySQL8.0 版本需要更换驱动为“com.mysql.cj.jdbc.Driver”，之前的“com.mysql.jdbc.Driver”已经不能在 MySQL 8.0 版本使用了，官方文档链接：https://dev.mysql.com/doc/connector-j/8.0/en/connector-j-api-changes.html；
描述如下：The name of the class that implements Java.sql.Driver in MySQL Connector/J has changed from com.mysql.jdbc.Driver to com.mysql.cj.jdbc.Driver. The old class name has been deprecated.
另外 mysql-connector-java 也推荐更新到 8.0 的版本（https://dev.mysql.com/downloads/connector/j/）。
综上修改以下两点：
1. 更新 mysql-connector-java 版本：
<!– https://mvnrepository.com/artifact/mysql/mysql-connector-java –>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.11</version>
</dependency>
2. 更换驱动：
<jdbcConnection driverClass=”com.mysql.cj.jdbc.Driver” connectionURL=”jdbc:mysql://127.0.0.1:3306/test?
useUnicode=true&characterEncoding=utf-8&useSSL=false” userId=”root” password=”root”/>
配置好以上两点，运行 mybatis-generator-maven-plugin，接着报错如下：
Failed to execute goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.5:generate (default-cli) on project songci-serv: The server time zone value ‘Öйú±ê׼ʱ¼ä’ is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support. -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
报时区错误，解决方法执行命令给 MySQL 服务器设置时区为东八区，这个是 com.mysql.cj.jdbc.Driver 需要指定的：
mysql> set global time_zone=’+8:00′;
Query OK, 0 rows affected
Navicat 中命令列介面执行即可。或者在数据库连接配置中加上 serverTimezone=GMT%2B8（代表东八区），如下：
connectionURL=”jdbc:mysql://127.0.0.1:3306/songci?useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=GMT%2B8″
