(已解决)### Error querying database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException:

原创已于 2022-12-02 08:34:33 修改 · 4.9w 阅读

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#数据库 #java #mybatis

于 2019-12-23 19:16:47 首次发布

本文详细解析了在使用Spring框架时遇到的JDBC连接数据库失败的问题，并提供了具体的解决方案。问题核心在于数据库配置文件jdbc.properties中端口号设置错误，将错误的8080端口更正为正确的3306端口后，成功解决了连接问题。

问题：jdbc不能连接

org.springframework.jdbc.CannotGetJdbcConnectionException:

如下报错：

Error querying database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (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.)

The error may exist in file [E:\Workspaces\eclipse.metadata.plugins\org.eclipse.wst.server.core\tmp3\wtpwebapps\teacher_information\WEB-INF\classes\com\qhua\mapper\UserMapper.xml]

The error may involve com.qhua.mapper.UserMapper.findById

The error occurred while executing a query

Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (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.)] with root cause
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)
at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:568)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1014)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2199)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2230)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2025)
at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:778)
at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:47)
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:425)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:386)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330)
at org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38)
at org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:294)
at org.apache.commons.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1247)