错误信息

应用在启动过程中，在连接数据库阶段报错，关键错误信息如下：

Caused by: java.sql.SQLException: The server time zone value '�й���׼ʱ��' 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.
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:129) ~[mysql-connector-java-8.0.21.jar:8.0.21]
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) ~[mysql-connector-java-8.0.21.jar:8.0.21]
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89) ~[mysql-connector-java-8.0.21.jar:8.0.21]
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63) ~[mysql-connector-java-8.0.21.jar:8.0.21]
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:73) ~[mysql-connector-java-8.0.21.jar:8.0.21]
	at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:76) ~[mysql-connector-java-8.0.21.jar:8.0.21]
	at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:836) ~[mysql-connector-java-8.0.21.jar:8.0.21]
	at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:456) ~[mysql-connector-java-8.0.21.jar:8.0.21]
	at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:246) ~[mysql-connector-java-8.0.21.jar:8.0.21]
	at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:197) ~[mysql-connector-java-8.0.21.jar:8.0.21]
	at com.zaxxer.hikari.util.DriverDataSource.getConnection(DriverDataSource.java:136) ~[HikariCP-3.2.0.jar:na]
	at com.zaxxer.hikari.pool.PoolBase.newConnection(PoolBase.java:369) ~[HikariCP-3.2.0.jar:na]
	at com.zaxxer.hikari.pool.PoolBase.newPoolEntry(PoolBase.java:198) ~[HikariCP-3.2.0.jar:na]
	at com.zaxxer.hikari.pool.HikariPool.createPoolEntry(HikariPool.java:467) ~[HikariCP-3.2.0.jar:na]
	at com.zaxxer.hikari.pool.HikariPool.checkFailFast(HikariPool.java:541) ~[HikariCP-3.2.0.jar:na]
	at com.zaxxer.hikari.pool.HikariPool.<init>(HikariPool.java:115) ~[HikariCP-3.2.0.jar:na]
	at com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:112) ~[HikariCP-3.2.0.jar:na]
	at com.zaxxer.hikari.HikariDataSource$$FastClassBySpringCGLIB$$eeb1ae86.invoke(<generated>) ~[HikariCP-3.2.0.jar:na]
	at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) ~[spring-core-5.1.16.RELEASE.jar:5.1.16.RELEASE]
	at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:752) ~[spring-aop-5.1.16.RELEASE.jar:5.1.16.RELEASE]
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-5.1.16.RELEASE.jar:5.1.16.RELEASE]
	at org.springframework.aop.support.DelegatingIntroductionInterceptor.doProceed(DelegatingIntroductionInterceptor.java:136) ~[spring-aop-5.1.16.RELEASE.jar:5.1.16.RELEASE]
	at org.springframework.aop.support.DelegatingIntroductionInterceptor.invoke(DelegatingIntroductionInterceptor.java:124) ~[spring-aop-5.1.16.RELEASE.jar:5.1.16.RELEASE]
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.16.RELEASE.jar:5.1.16.RELEASE]
	at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:691) ~[spring-aop-5.1.16.RELEASE.jar:5.1.16.RELEASE]
	at com.zaxxer.hikari.HikariDataSource$$EnhancerBySpringCGLIB$$eb6775d8.getConnection(<generated>) ~[HikariCP-3.2.0.jar:na]
	at org.springframework.jdbc.datasource.DataSourceUtils.fetchConnection(DataSourceUtils.java:158) ~[spring-jdbc-5.1.16.RELEASE.jar:5.1.16.RELEASE]
	at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:116) ~[spring-jdbc-5.1.16.RELEASE.jar:5.1.16.RELEASE]
	at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:79) ~[spring-jdbc-5.1.16.RELEASE.jar:5.1.16.RELEASE]
	... 161 common frames omitted

原因分析

如果你的数据库驱动（mysql-connector-java）版本过高（如：8.0.21），而数据库版本较低（如：5.7.12），就会出现这种情况。

解决方法

在jdbc连接后面加上serverTimezone=UTC， UTC是统一标准世界时间

url: jdbc:mysql://localhost:3306/db?useUnicode=true&characterEncoding=utf-8&serverTimezone=UTC