springboot 连接 mysql 报错记录

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2018-07-03 19:52:02.183 ERROR 1412 --- [-Create-1139431] com.alibaba.druid.pool.DruidDataSource   : create connection SQLException, url: jdbc:mysql://localhost:3306/lailai, errorCode 0, state S1000

java.sql.SQLException: Unknown initial character set index '255' received from server. Initial client character set can be forced via the 'characterEncoding' property.
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1055) ~[mysql-connector-java-5.1.9.jar:na]
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956) ~[mysql-connector-java-5.1.9.jar:na]
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926) ~[mysql-connector-java-5.1.9.jar:na]
	at com.mysql.jdbc.ConnectionImpl.configureClientCharacterSet(ConnectionImpl.java:1734) ~[mysql-connector-java-5.1.9.jar:na]
	at com.mysql.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:3539) ~[mysql-connector-java-5.1.9.jar:na]
	at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2151) ~[mysql-connector-java-5.1.9.jar:na]
	at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:776) ~[mysql-connector-java-5.1.9.jar:na]
	at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:46) ~[mysql-connector-java-5.1.9.jar:na]
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_171]
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_171]
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_171]
	at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_171]
	at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) ~[mysql-connector-java-5.1.9.jar:na]
	at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:352) ~[mysql-connector-java-5.1.9.jar:na]
	at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:284) ~[mysql-connector-java-5.1.9.jar:na]
	at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:149) ~[druid-1.1.9.jar:1.1.9]
	at com.alibaba.druid.filter.stat.StatFilter.connection_connect(StatFilter.java:218) ~[druid-1.1.9.jar:1.1.9]
	at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:143) ~[druid-1.1.9.jar:1.1.9]
	at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1515) ~[druid-1.1.9.jar:1.1.9]
	at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1578) ~[druid-1.1.9.jar:1.1.9]
	at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2466) ~[druid-1.1.9.jar:1.1.9]

解决方法:

配置文件数据库连接URL添加后缀

url: jdbc:mysql://localhost:3306/lailai?useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=Hongkong

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2018-07-03 19:59:49.462 ERROR 14100 --- [Create-15803549] com.alibaba.druid.pool.DruidDataSource   : create connection SQLException, url: jdbc:mysql://localhost:3306/lailai?useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=Hongkong, errorCode 0, state 08001

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_171]
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_171]
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_171]
	at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_171]
	at com.mysql.jdbc.Util.handleNewInstance(Util.java:389) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.Util.getInstance(Util.java:372) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:958) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:937) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:872) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2316) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2069) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:794) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:44) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_171]
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_171]
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_171]
	at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_171]
	at com.mysql.jdbc.Util.handleNewInstance(Util.java:389) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:399) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:325) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:149) ~[druid-1.1.9.jar:1.1.9]
	at com.alibaba.druid.filter.stat.StatFilter.connection_connect(StatFilter.java:218) ~[druid-1.1.9.jar:1.1.9]
	at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:143) ~[druid-1.1.9.jar:1.1.9]
	at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1515) ~[druid-1.1.9.jar:1.1.9]
	at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1578) ~[druid-1.1.9.jar:1.1.9]
	at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2466) ~[druid-1.1.9.jar:1.1.9]
Caused by: java.lang.NullPointerException: null
	at com.mysql.jdbc.ConnectionImpl.getServerCharset(ConnectionImpl.java:2989) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.MysqlIO.sendConnectionAttributes(MysqlIO.java:1873) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1802) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1206) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2239) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2270) ~[mysql-connector-java-5.1.35.jar:5.1.35]
	... 16 common frames omitted

问题分析:

        由于mysql版本为8.0,而mysql-connector-java为5.1.35 , 所以连接不成功原因是 版本不兼容 

解决方法:

     mysql
     mysql-connector-java
     8.0.11


配置文件修改:
driver-class-name: com.mysql.cj.jdbc.Driver