com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_172]
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) ~[na:1.8.0_172]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) ~[na:1.8.0_172]
at java.lang.reflect.Constructor.newInstance(Unknown Source) ~[na:1.8.0_172]
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.Util.getInstance(Util.java:408) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:919) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:861) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2096) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2021) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:776) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_172]
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) ~[na:1.8.0_172]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) ~[na:1.8.0_172]
at java.lang.reflect.Constructor.newInstance(Unknown Source) ~[na:1.8.0_172]
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:386) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330) ~[mysql-connector-java-5.1.46.jar:5.1.46]
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: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 2 milliseconds ago. The last packet sent successfully to the server was 0 milliseconds ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_172]
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) ~[na:1.8.0_172]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) ~[na:1.8.0_172]
at java.lang.reflect.Constructor.newInstance(Unknown Source) ~[na:1.8.0_172]
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:990) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3562) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3462) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3903) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:871) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1714) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1224) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2190) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2037) ~[mysql-connector-java-5.1.46.jar:5.1.46]
... 16 common frames omitted
Caused by: java.io.EOFException: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost.
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:3014) ~[mysql-connector-java-5.1.46.jar:5.1.46]
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3472) ~[mysql-connector-java-5.1.46.jar:5.1.46]
... 23 common frames omitted
连接数据库密码打错了
密码打错之后存在ip被拉黑的问题，当前ip无法连接服务器数据库 报错
MySql Host is blocked because of many connection errors; unblock with 'mysqladmin flush-hosts'
在服务器navicat 新建查询 页面运行flush hosts 解决