mysql-connector-java连接失败问题

跑了很久的项目jar突然跑不起来了,日志显示mysql驱动空指针异常,最终排查发现是环境变量设置的字符集驱动识别不了
解决方法:
1.替换驱动包版本为5.1.16 
5.1.35增加了相关异常
参考:https://bugs.mysql.com/bug.php?id=72630

2.修改环境变量java全局字符集配置为utf-8

堆栈信息:
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
	at java.lang.reflect.Constructor.newInstance(Unknown Source)
	at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
	at com.mysql.jdbc.Util.getInstance(Util.java:384)
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1013)
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:987)
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:973)
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:918)
	at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2588)
	at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2321)
	at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:832)
	at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:46)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
	at java.lang.reflect.Constructor.newInstance(Unknown Source)
	at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
	at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:417)
	at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:344)
	at org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38)
	at org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:582)
	at org.apache.commons.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1556)
	at org.apache.commons.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1545)
	... 73 more
Caused by: java.lang.NullPointerException
	at com.mysql.jdbc.Buffer.(Buffer.java:53)
	at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1738)
	at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1288)
	at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2506)
	at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2539)
	... 87 more