项目登录时报错：com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException-CSDN论坛

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项目登录时报错：com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException [问题点数：40分]

⋅项目登录时报错：com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException 更多帖子 关注私信空间博客 xiangyong8868 本版专家分：0 结帖率 0%: 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)
 at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
 at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
 at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
 at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
 at com.mysql.jdbc.Util.getInstance(Util.java:381)
 at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:984)
 at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956)
 at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926)
 at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2359)
 at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:776)
 at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46)
 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:422)
 at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
 at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:352)
 at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:284)
 at java.sql.DriverManager.getConnection(DriverManager.java:664)
 at java.sql.DriverManager.getConnection(DriverManager.java:247)
 at com.common.dbase.ConnManager$DBConnectionPool.newConnection(ConnManager.java:662)
 at com.common.dbase.ConnManager$DBConnectionPool.<init>(ConnManager.java:404)
 at com.common.dbase.ConnManager.createPools(ConnManager.java:272)
 at com.common.dbase.ConnManager.init(ConnManager.java:308)
 at com.common.dbase.ConnManager.<init>(ConnManager.java:51)
 at com.common.dbase.ConnManager.<clinit>(ConnManager.java:29)
 at com.common.dbase.DBManager.getResultSet(DBManager.java:35)
 at com.docker.servlet.UserLoginServlet.router(UserLoginServlet.java:80)
 at com.docker.servlet.UserLoginServlet.doGet(UserLoginServlet.java:39)
 at com.docker.servlet.UserLoginServlet.doPost(UserLoginServlet.java:49)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
 at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
 at com.common.filter.LoginFilter.doFilter(LoginFilter.java:59)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:218)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110)
 at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:506)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
 at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:962)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445)
 at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1115)
 at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637)
 at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
 at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
 at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
 at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
 at java.lang.Thread.run(Thread.java:745)
Caused by: com.mysql.jdbc.exceptions.jdbc4.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 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:422)
 at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
 at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)
 at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:343)
 at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2283)
 ... 46 more
Caused by: java.net.ConnectException: Connection refused
 at java.net.PlainSocketImpl.socketConnect(Native Method)
 at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
 at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
 at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
 at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
 at java.net.Socket.connect(Socket.java:589)
 at java.net.Socket.connect(Socket.java:538)
 at java.net.Socket.<init>(Socket.java:434)
 at java.net.Socket.<init>(Socket.java:244)
 at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:253)
 at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:292)
 ... 47 more

0 2017-09-21 10:00:09

回复数 3 只看楼主引用举报楼主

⋅关于return null 的疑惑 更多帖子 关注私信空间博客 G.Jagger 本版专家分：400: Caused by: java.net.ConnectException: Connection refused
检查一下数据库参数配置

0 2017-09-21 10:09:52

只看TA 引用举报 #1 得分 0

针对mysql8.0报错：com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create 折腾了好久，后来发现是版本问题，驱动和数据库不匹配导致。原来用的是5.1.37的驱动。数据库是mysql5.7，可以连接成功。就在我把数据库换成了8.0之后，所有的买点啥都报标题里的错误了。换成了下边这个驱动就OK了。瞬间心情好了有没有！这个坑。实在是深啊！有需要的朋友自行下载吧。我在mysql官网没找到？？？？然后在maven里弄出来的。...

一剑侵心 本版专家分：632: 检查一下数据库配置是否正确

0 2017-09-21 11:29:44

只看TA 引用举报 #2 得分 0

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException异常解决方法在使用MySQL驱动进行JDBC时候出现了以下异常 Exception in thread "main" com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. at sun.reflect.NativeConstru...

⋅讨论贴，讨论一下react-native方面的知识 ⋅怎么样新建论坛的专区 ⋅Jquery dialog 更多帖子 关注私信空间博客 枫醉秋 本版专家分：5850: 数据库连接被拒绝连接，检查数据库的配置或者网络的设置

0 2017-09-21 10:49:47

只看TA 引用举报 #3 得分 0

异常：MySQLNonTransientConnectionException: Could not create connection to database server.解决方法异常：MySQLNonTransientConnectionException: Could not create connection to database server.异常原因解决方法异常 com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to...

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Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was 52,705,191 milliseconds ago. The last packet sent successfully to the serv

Error querying database. Cause: com.mysql.jdbc.exceptions.MySQLNonTransientConnectionException: Cli: 用eclipse 和mybatis运行时报的错误是mySQL的配置问题` Error querying database. Cause: com.mysql.jdbc.exceptions.MySQLNonTransientConnectionException: Client does not support authentication protocol requested by serv...

JDBC连接Mysql数据库失败: 求助,不知道哪里错了 ,运行错误提示 com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not c

新手连接Mysql,JDBC报错: package com; import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; public class ConnctionTest { public static void main(String[] args) throws ClassNotFoundException, SQLException { //加载驱动 Class.forName("con.mysql.jdbc.Dricer"); Connection conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/test","root1","root"); System.out.println(conn); } } 架包：5.1.25 错误信息： ![图片说明](https://img-ask.csdn.net/upload/201712/07/1512619915_824442.png)

难以置信的报错：已解决com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown database ‘test’: 报错信息：未知的数据库‘test’ 很显然，我觉得大家不会这么不注意不建库，那么具体原因呢？发现自己的服务中MySQL有两个，另一个是前些日子本地搭建禅道的时候引入的数据库，很显然，java代码配置的数据库找localhost的时候，并没有找自己想连接的数据库解决方法：关闭该服务 ...

这个错误如何解决啊 Caused by: com.mysql.jdbc.CommunicationsException: Communications link: 这个错误如何解决啊 Caused by: com.mysql.jdbc.CommunicationsException: Communications link 在网上查了下 Mysql服务器默认的“

jdbc连接数据库的com.mysql.jdbc.CommunicationsException问题: 我使用jdbc连接数据库，连接不上，上网搜了很多，有人说是数据库请求超时问题，也有说是数据库url，账号或者密码配置错误，我检查了都没有问题。还有一点奇怪的是，我用jdbc-odbc桥连接又可以连上数据库，用可视化工具也可以连上，但是用jdbc方式连接不上。。。我现在想着应该是哪里的配置有问题，请教各位大神，看看有谁知道或者遇到过，谢谢大家了这是我的程序 ``` public static void main(String[] args) { Connection ct = null; Statement sm = null; ResultSet rs = null; try { //1、加载驱动（作用是把需要的驱动程序加入内存） Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); //2、得到连接（指定连接到哪个数据源） //如果配置数据源选择的是Windows nt验证方式，则不需要用户名和密码 ct = DriverManager.getConnection("jdbc:odbc:MyTest", "root", "root"); //3、创建Statement或者PreparedStatement[区别] //Statement用处是,用于发送sql语句 sm = ct.createStatement(); //4、执行（crud、备份数据库、删除数据库......） //查询，显示所有部门信息 //ResultSet结果集,可以理解成一个表行的结果集 rs = sm.executeQuery("select * from dept"); //因为rs指向结果集的第一行的前一行， //循环取出 while (rs.next()) { int deptno = rs.getInt(1); String dname = rs.getString(2); String loc = rs.getString(3); System.out.println(deptno+" "+dname+" "+loc); } } catch(Exception e) { e.printStackTrace(); } finally { //关闭资源 //关闭顺序是谁后创建谁先关闭 try { //为了程序健壮 if (rs != null) { rs.close(); } if (sm != null) { sm.close(); } if (ct != null) { ct.close(); } } catch (SQLException e) { e.printStackTrace(); } } } ``` 这些是报的异常 ``` com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception: ** BEGIN NESTED EXCEPTION ** java.net.SocketException MESSAGE: Permission denied: recv failed STACKTRACE: java.net.SocketException: Permission denied: recv failed at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.read(SocketInputStream.java:152) at java.net.SocketInputStream.read(SocketInputStream.java:122) at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:105) at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:148) at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:176) at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1899) at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:481) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:964) at com.mysql.jdbc.Connection.createNewIO(Connection.java:2544) at com.mysql.jdbc.Connection.(Connection.java:1474) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:264) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:146) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:195) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:184) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:200) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1086) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquireAndDecrementPendingAcquiresWithinLockOnSuccess(BasicResourcePool.java:1073) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:44) at com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:648) ** END NESTED EXCEPTION ** Last packet sent to the server was 0 ms ago. at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:552) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:964) at com.mysql.jdbc.Connection.createNewIO(Connection.java:2544) at com.mysql.jdbc.Connection.(Connection.java:1474) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:264) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:146) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:195) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:184) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:200) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1086) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquireAndDecrementPendingAcquiresWithinLockOnSuccess(BasicResourcePool.java:1073) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:44) at com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:648) ```

MySQL连接问题： MySQLNonTransientConnectionException:Communications link failure during rollback(): 昨天线上出现了这样的一个问题：MySQLNonTransientConnectionException:Communications link failure during rollback() 初步判定应用的连接配置有问题。方案一：修改DBCP参数参数说明： timeBetweenEvictionRunsMillis (设置的Evict线程的时间，单位：毫秒，即每隔多少时间去检测一次空闲连...

运行逆向工程报错com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create conne: 错误信息： com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at ...

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create的错误: 错误原因：Mybatis连接数据库的时候报错 解决办法： 1.经查询发现自己的数据包的导错了，数据库版本是：8.0.16，导的是5.7.26的包 2.重新导入8.0.16，解决 ...

activiti中出现Error querying database.Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: 在activiti项目中出现错误： org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL sy

系统正常一段时间后出现com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to

eclipse连接mysql8.0的一些错误总结: 弄这个mysql弄得简直没脾气，总结一下遇到的错误吧首先要把mysql-connector-java-5.1.7-bin-jar加进去，当然别的版本也行吧右键项目–BuildPath–configur那个–Libraries–Add Exteral JARS 填进来大概是这个，哦，要配置环境变量，这些都弄好了之后我开始写代码连接 import java.sql.Connection...

【已解决】Hive启动后报错：FAILED: LockException [Error 10280]: Error communicating with the metastore: Hive，解决报错：ERROR [main]: metastore.RetryingHMSHandler (RetryingHMSHandler.java:invoke(159)) - MetaException(message:Unable to update transaction database com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'hive.txns' doesn't exist

springboot 连接 mysql 报错记录: 2018-07-03 19:52:02.183 ERROR 1412 --- [-Create-1139431] com.alibaba.druid.pool.DruidDataSource : create connection SQLException, url: jdbc:mysql://localhost:3306/lailai, errorCode 0, state S1000 j...

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException异常原因解析: 今天，博主在写项目时遇到了com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException异常，这种异常变态到极致，一般都是自己的sql语句写错了。 @Insert({"insert into ",TABLE_NAME ," (",INSET_FIELDS, ") values (#{name},#{password}

解决MySQLNonTransientConnectionException: Could not create connection to database server.问题: 错误原因1：jdbc连接没有关闭解决方法：关闭连接 错误原因2：jdbc连接操作在主线程中解决方法：在子线程中进行jdbc连接操作

java和mysql连接的问题,大家帮我看下怎么错了呢: import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import com.m

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionEception:could not create connection to d: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionEception:could not create connection to database server.attempted reconnect 3 times .giving up ... Caused by:java.util.NoSuchElementException...

Could not create connection to database server.错误: java.sql.SQLNonTransientConnectionException: Could not create connection to database server. at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:676) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:663) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:653) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:638) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:606) at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:1857) at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:1673) at com.mysql.cj.jdbc.ConnectionImpl.(ConnectionImpl.java:656) at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:349) at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:221) at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:310) at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:203) at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:715) at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:647) at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:466) at org.apache.tomcat.jdbc.pool.ConnectionPool.(ConnectionPool.java:141) at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:118) at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:107) at org.apache.tomcat.jdbc.pool.DataSourceProxy.getConnection(DataSourceProxy.java:131) at org.springframework.jdbc.datasource.DataSourceTransactionManager.doBegin(DataSourceTransactionManager.java:204) at org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:373) at org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:427) at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:276) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:655) at com.my.demo.service.DemoService$$EnhancerBySpringCGLIB$$cf6aac2.test() at com.my.demo.web.DemoController.login(DemoController.java:26) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:497) at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:832) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:743) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:961) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:895) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:967) at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:858) at javax.servlet.http.HttpServlet.service(HttpServlet.java:687) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:843) at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:845) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1689) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:121) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1668) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:581) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143) at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:548) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:226) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1174) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:511) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1106) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:213) at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:119) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:134) at org.eclipse.jetty.server.Server.handle(Server.java:524) at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:319) at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:253) at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:273) at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:95) at org.eclipse.jetty.io.SelectChannelEndPoint$2.run(SelectChannelEndPoint.java:93) at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.executeProduceConsume(ExecuteProduceConsume.java:303) at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.produceConsume(ExecuteProduceConsume.java:148) at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.run(ExecuteProduceConsume.java:136) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:671) at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:589) at java.lang.Thread.run(Thread.java:745)

jeecg启动报错“com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create con...: 在运行“maven build”-->“tomcat:run”之后，报如下错误： com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. at sun.reflect.NativeConstruc...

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientC: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed 原因:刚使用的连接没有关闭,当第二次调用时不为空，所以直接返回一个关闭状态的连接。例如:1.静态的连接2使用某个对数据库操作的方法做逻辑运算.总的来说都是粗心...

Java与mysql数据库编程中遇见“Before start of result set at com.mysql.jdbc.SQLError.createSQLException” 的解决办法...: 这个Bug是因为在取出ResultSet对象，对其进行操作时，没有采用.next()方法将ResultSet对象的光标移至指定行，不管Statement对象执行SQL语句是否十分确定能搜出记录，也不可以在没有ResultSet的next()方法之前直接对ResultSet对象进行取值转载于:https://www.cnblogs.com/akiradunn/p/5771513.html...

mybatis向mysql插入数据时出错，跪求大神指点: action里有个saveNews方法，代码如下 public String saveNews(){ this.news.setTime(Utils.nowTime()); this.news.set

关于JDBC中No operations allowed after connection closed的问题: public static Operater check(String name, String password) { Operater operater=new Operater();//操作员信

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: 错误怎么解决: 我用的一个简单的测试MySql数据库JDBC连接是否成功，程序没有错误，但打开网页时会出现：com.mysql.jdbc.exceptions.jdbc4.CommunicationsExceptio

MySQL错误com.mysql.jdbc.exceptions.jdbc4.CommunicationsException:: 我在尝试与mysql建立连接的时候抛出以下异常。 MySQL错误com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: 同时问题定位出错的地方在： conn=DriverManager.getConnection(url, user, password); 这句话中，原本的定义为： static final String url...

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure解决: 介绍 com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet successfully received from the server was 5,030 milliseconds ago. The last packet sent succe

Caused by: Could not create connection to database server.: Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create co 在我遇到这个错误后（当时真难受），然后我在网络上查找到了一些方法，具体如下，希望对你们有用！（我的问题最后已解决）修改密码失败启动Tomcat服务后依然**报错（难受）** 重新启动mysql...

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException解决方式: 将数据库由Oracle切换到Mysql中，把数据库连接配置由xml中移到hibernate.properties，启动时报错: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'hibernate_example.all_sequences' doesn't exist 22:58:24,581 ERROR

jdbc Before start of result set at com.mysql.jdbc.SQLError.createSQLException(SQ: Before start of result set at com.mysql.jdbc.SQLError.createSQLException(SQ 无论是第几次获取第几个数据库的返回结果，必须rs.next().

mybatis连接mysql8.0数据库时报错：com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: 在网上看到许多解决这个的错误；第一步：查看数据库是否开启服务。第二步：大小写以及字符集标准注意。第三步：查看自己pom文件连接驱动是否对应自己版本。我的问题出在第三步pom文件对应版本不对 ...

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet success: 新发布的应用，昨天一天正常运行，没有问题，但是今天早上刚刚一测试就报错： com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The la

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link fa: org.springframework.transaction.CannotCreateTransactionException: Could not open JDBC Connection for

异常:com.mysql.jdbc.exceptions.jdbc4.communicatio: 异常:com.mysql.jdbc.exceptions.jdbc4.communicationException:communication link failure last packet sent to the server was 0 ms ago at sun.refect.nativecon.........等等我用的是mysql数据库，Java文件可以编译，但是一运行就出现错误

Eclipse用JDBC连接不上MySql，求解决办法: **使用JDBC的方法连接不上MySQL，我的网络是校园网，登陆后IP会变化，不知道这个对连接有没有什么影响，用的是mysql 5.6 以前用JDBC连接上过的，但是现在就不行了，不清楚原因，也在网上找过，但是找不到解决的办法，连接的JAR包是mysql-connector-java-5.1.26-bin.jar，请知道的大神解答一下小弟，还有就是使用Oracle用JDBC是连接得上的，使用的地址也是localhost，但是在用JDBC连接数据库查看的时候，在使用preparedStatement返回的genernatekeys无法使用getInt这个方法，所以想用mysql，因为视频教程中也是用MySQL的，并且是能用getInt这是方法的，所以想用mysql，麻烦各位大哥帮帮忙** 出现的错误如下： import java.sql.*; public class TestMysqlConnection { public static void main (String[] args) { Connection conn = null; try { Class.forName("com.mysql.jdbc.Driver"); conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/bbs","root","123456"); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); } finally { try { if(conn != null) { conn.close(); conn = null; } } catch (SQLException e) { e.printStackTrace(); } } } 错误如下： com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Communication link failure, message from server: "Can't get hostname for your address" 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:411) at com.mysql.jdbc.Util.getInstance(Util.java:386) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1015) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:989) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:975) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1112) at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2486) at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2519) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2304) at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:834) 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:411) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:416) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:346) at java.sql.DriverManager.getConnection(Unknown Source) at java.sql.DriverManager.getConnection(Unknown Source) at TestMysqlConnection.main(TestMysqlConnection.java:8)

解决com.mysql.jdbc.exceptions.jdbc4.CommunicationsException:: 有时候mysql会遇到： com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was 126,421,823 milliseconds ago. The last packet sent successfully to the...

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Data source rejected establish...: 报错： com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Data source rejected establishment of connection, message from server: "Too many connections" at sun.reflect.GeneratedConstr...

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to...: 昨天在自己电脑上连接mysql启动web程序时，报出一些错误： 2018-09-17 16:30:28 ERROR DruidDataSource:646 : dataSource init errorcom.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection ...

Spring整合mybatis--MySQLNonTransientConnectionException: Could not create connection to database serve: Spring整合mybatis并使用driud数据库连接池，启动测试类就报”MySQLNonTransientConnectionException: Could not create connection to database server.“，检查了一番配置文件没发现问题，而且我之前用过这些配置，按理说没问题。各种百度、谷歌没结果，想起来装了mysql 8.0，估计是这个问题...

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