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2021-11-27 14:34:42.899 [Druid-ConnectionPool-Create-1427013366] ERROR com.alibaba.druid.pool.DruidDataSource:2781 - create connection SQLException, url: jdbc:mysql://127.0.0.1:3306/jeecg-boot?characterEncoding=UTF-8&useUnicode=true&useSSL=false&tinyInt1isBit=false&allowPublicKeyRetrieval=true&serverTimezone=Asia/Shanghai, errorCode 0, state 08S01
com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
        at com.mysql.cj.jdbc.exceptions.SQLError.createCommunicationsException(SQLError.java:174)
        at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:64)
        at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:836)
        at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:456)
        at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:246)
        at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:198)
        at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:156)
        at com.alibaba.druid.filter.FilterAdapter.connection_connect(FilterAdapter.java:787)
        at com.alibaba.druid.filter.FilterEventAdapter.connection_connect(FilterEventAdapter.java:38)
        at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:150)
        at com.alibaba.druid.filter.FilterAdapter.connection_connect(FilterAdapter.java:787)
        at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:150)
        at com.alibaba.druid.filter.stat.StatFilter.connection_connect(StatFilter.java:218)
        at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:150)
        at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1646)
        at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1710)
        at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2779)
Caused by: com.mysql.cj.exceptions.CJCommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
        at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61)
        at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:105)
        at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:151)
        at com.mysql.cj.exceptions.ExceptionFactory.createCommunicationsException(ExceptionFactory.java:167)
        at com.mysql.cj.protocol.a.NativeProtocol.readMessage(NativeProtocol.java:544)
        at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:708)
        at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:685)
        at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:134)
        at com.mysql.cj.protocol.a.NativeAuthenticationProvider.proceedHandshakeWithPluggableAuthentication(NativeAuthenticationProvider.java:469)
        at com.mysql.cj.protocol.a.NativeAuthenticationProvider.connect(NativeAuthenticationProvider.java:174)
        at com.mysql.cj.protocol.a.NativeProtocol.connect(NativeProtocol.java:1348)
        at com.mysql.cj.NativeSession.connect(NativeSession.java:157)
        at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:956)
        at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:826)
        ... 14 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.cj.protocol.FullReadInputStream.readFully(FullReadInputStream.java:67)
        at com.mysql.cj.protocol.a.SimplePacketReader.readHeader(SimplePacketReader.java:63)
        at com.mysql.cj.protocol.a.SimplePacketReader.readHeader(SimplePacketReader.java:45)
        at com.mysql.cj.protocol.a.NativeProtocol.readMessage(NativeProtocol.java:538)
        ... 23 common frames omitted
2021-11-27 14:34:59.834 [Druid-ConnectionPool-Create-1427013366] ERROR com.alibaba.druid.pool.DruidDataSource:2781 - create connection SQLException, url: jdbc:mysql://127.0.0.1:3306/jeecg-boot?characterEncoding=UTF-8&useUnicode=true&useSSL=false&tinyInt1isBit=false&allowPublicKeyRetrieval=true&serverTimezone=Asia/Shanghai, errorCode 0, state 08S01
com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure