Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException

本是古典何须时尚 2022-03-22 13:44 719阅读 0赞

原因：数据库的版本是![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3c4OTM5MzI3NDc_size_16_color_FFFFFF_t_70][]

程序中引入的是5点几的链接。

解决：修改程序中代码的引入版本为8以上即可！

org.apache.ibatis.exceptions.PersistenceException:   
\#\#\# Error querying database.  Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.  
\#\#\# The error may exist in EmployeeMapper.xml  
\#\#\# The error may involve com.atguigu.mybatis.dao.EmployeeMapper.getEmpById  
\#\#\# The error occurred while executing a query  
\#\#\# Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.  
    at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30)  
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:150)  
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141)  
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:77)  
    at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:82)  
    at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:53)  
    at com.sun.proxy.$Proxy8.getEmpById(Unknown Source)  
    at com.atguigu.mybatis.test.MyBatisTest.test01(MyBatisTest.java:84)  
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)  
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)  
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)  
    at java.base/java.lang.reflect.Method.invoke(Unknown Source)  
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)  
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)  
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)  
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)  
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)  
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)  
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)  
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)  
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)  
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)  
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)  
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)  
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)  
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)  
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)  
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:538)  
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:760)  
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:460)  
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:206)  
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.  
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)  
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)  
    at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)  
    at java.base/java.lang.reflect.Constructor.newInstance(Unknown Source)  
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)  
    at com.mysql.jdbc.Util.getInstance(Util.java:387)  
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:919)  
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898)  
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887)  
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:862)  
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2331)  
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2084)  
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:795)  
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:44)  
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)  
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)  
    at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)  
    at java.base/java.lang.reflect.Constructor.newInstance(Unknown Source)  
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)  
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:400)  
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:327)  
    at java.sql/java.sql.DriverManager.getConnection(Unknown Source)  
    at java.sql/java.sql.DriverManager.getConnection(Unknown Source)  
    at org.apache.ibatis.datasource.unpooled.UnpooledDataSource.doGetConnection(UnpooledDataSource.java:201)  
    at org.apache.ibatis.datasource.unpooled.UnpooledDataSource.doGetConnection(UnpooledDataSource.java:196)  
    at org.apache.ibatis.datasource.unpooled.UnpooledDataSource.getConnection(UnpooledDataSource.java:93)  
    at org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:385)  
    at org.apache.ibatis.datasource.pooled.PooledDataSource.getConnection(PooledDataSource.java:89)  
    at org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:138)  
    at org.apache.ibatis.transaction.jdbc.JdbcTransaction.getConnection(JdbcTransaction.java:60)  
    at org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:336)  
    at org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:84)  
    at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:62)  
    at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:324)  
    at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156)  
    at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109)  
    at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:83)  
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148)  
    ... 29 more  
Caused by: java.lang.NullPointerException  
    at com.mysql.jdbc.ConnectionImpl.getServerCharset(ConnectionImpl.java:3004)  
    at com.mysql.jdbc.MysqlIO.sendConnectionAttributes(MysqlIO.java:1908)  
    at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1837)  
    at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1207)  
    at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2254)  
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2285)

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3c4OTM5MzI3NDc_size_16_color_FFFFFF_t_70]: /images/20220322/0f8f546d7cd34eed967738d76aec5171.png