请求！jdbc连接mysql数据库出现“Communications link failure.The last packet sent…”（附源码及错误信息）-CSDN论坛

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请求！jdbc连接mysql数据库出现“Communications link failure.The last packet sent…”（附源码及错误信息） [问题点数：20分]

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MySQL数据库提示：Communications link failure，The last packet succe Last modified：2013-10-08 14:16:47 ********************************************** web网站使用MySQL数据库，今天突然报以下错误： Communications link failure，The last packet successfully received from the ...

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连接MySQL数据库时出现 Communications link failure The last packet sent successfully to the server was 0 mill: 第一次写csdn博客，略有紧张。java小小白一个，如有错误，还望各位大神指正才是。华丽丽的分割线~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~·~~~ 在做实验的过程中遇到了上述错误提示，百度的好多个方法，如下图：（来源于CSDN的其他人的博客解决方法，没看懂最后一个什么意思，都没有解决我的问题|||）最终解决办法是：...

多线程连接MySQL数据库，报 Communications link failure: 大概是这样的思路，扫描2000+的MySQL服务器，通过我的弱口令表去挨个连接他们（大概100个账户），看看能否成功，如果成功则证明检查不合格。共5个thread，一个thread中包含一个大循环遍历账户表，然后每次new 一个DataBaseInfo ,调用ConnectDatabase()这个来判断是否成功。当运行一段时间后，出现Communications link failure，最终所有的线程都会停止在ConnectDatabase()中，不抛异常，不停止。用的jdk1.5rnpublic class DataBaseInfo rnrn //do morern public boolean ConnectDatabase()rn rn tryrn rn Class.forName(driver); rn if (conn!=null)rn rn conn.close(); rn rn DriverManager.setLoginTimeout(120);rn conn=DriverManager.getConnection(this.Url,this.Account,this.Password);rn //SimpleLogger.Write("Succeeded connecting to the Database!");rn conn.close();rn return true; rn rn catch(Exception e)rn rn //SimpleLogger.WriteError("Database: Error:"); rn System.out.println(this.Url+this.Account+this.Password+"---"+e.getMessage());rn e.printStackTrace();rn rn this.Close();rn return false;rn rn rn

用MyEclipse6连接mysql数据库时出现Communications link failure: 我装了mysql服务，也装了navicat，用mysql连接本地是可以的，可是连接别人的机器出连接不成功！ rnrn然后用MyEclipse6.6随便写一个Java程序，连接mysql数据库时出现Communications link failure错，具体错误如下： rnrncom.mysql.jdbc.CommunicationsException: Communications link failure rnrnLast packet sent to the server was 0 ms ago. rnat com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1070) rnat com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2120) rnat com.mysql.jdbc.ConnectionImpl. (ConnectionImpl.java:723) rnat com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:298) rnat com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:282) rnat java.sql.DriverManager.getConnection(Unknown Source) rnat java.sql.DriverManager.getConnection(Unknown Source) rnat com.stu.entity.TestCon.main(TestCon.java:17) rnrn如果哪位遇到过，请帮我解答一下，经理他说不管我了，要我把它解决掉！ rnrn急急急。。。。。。 rn谢谢啦！！！！！！

Java程序连接mysql数据库出现CommunicationsException: Communications link failure错误的问题: [img=https://img-bbs.csdn.net/upload/201812/20/1545311440_204967.png][/img][img=https://img-bbs.csdn.net/upload/201812/20/1545311440_427696.png][/img][img=https://img-bbs.csdn.net/upload/201812/20/1545311440_722711.png][/img]rnrnrnrn生产一直暴这个rn百度了下说以下操作可以解决这个问题,但是也试了没用求大神请教rnwait_timeout=31536000 rnrninteractive_timeout=31536000 rnrn rnrn将过期时间修改为1年。 rnrn rnrn二是在连接URL上添加参数：&autoReconnect=true&failOverReadOnly=false

Mysql jdbc 连接异常：Last packet sent to the server was 18948 ms ago: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failurernrnLast packet sent to the server was 18948 ms ago.rn at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)rn at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)rn at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)rn at java.lang.reflect.Constructor.newInstance(Unknown Source)rn at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)rn at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)rn at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3009)rn at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2895)rn at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3438)rn at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1951)rn at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2101)rn at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2554)rn at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1761)rn at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2046)rn at com.mysql.jdbc.PreparedStatement.executeBatchSerially(PreparedStatement.java:1650)rn at com.mysql.jdbc.PreparedStatement.executeBatch(PreparedStatement.java:1108)rn at com.cattsoft.parse.xml.sax.dao.EMSDao.execute(EMSDao.java:202)rn at com.cattsoft.parse.xml.sax.SaxHandler.dealRowData(SaxHandler.java:152)rn at com.cattsoft.parse.xml.sax.SaxHandler.startElement(SaxHandler.java:72)rn at org.apache.xerces.parsers.AbstractSAXParser.startElement(Unknown Source)rn at org.apache.xerces.parsers.AbstractXMLDocumentParser.emptyElement(Unknown Source)rn at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanStartElement(Unknown Source)rn at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(Unknown Source)rn at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)rn at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)rn at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)rn at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)rn at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source)rn at javax.xml.parsers.SAXParser.parse(Unknown Source)rn at javax.xml.parsers.SAXParser.parse(Unknown Source)rn at com.cattsoft.parse.xml.sax.SaxParser.call(SaxParser.java:37)rn at com.cattsoft.parse.xml.sax.SaxParser.call(SaxParser.java:1)rn at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)rn at java.util.concurrent.FutureTask.run(Unknown Source)rn at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)rn at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)rn at java.lang.Thread.run(Unknown Source)rnCaused by: java.net.SocketException: Software caused connection abort: recv failedrn at java.net.SocketInputStream.socketRead0(Native Method)rn at java.net.SocketInputStream.read(Unknown Source)rn at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:113)rn at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:160)rn at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:188)rn at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:2452)rn at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2906)rn ... 30 morernrn上面就是异常情况：mysql 已经设置21天的wait_outtime;连接方面：没一小段时间都会主动发送一个探测：select 1 from dual;不过没解决这个问题；

The last packet sent successfully to the server was 0 milliseconds ago. The driv: 在本地写好的程序，发到服务器上数据库连接失败；rnlinux+mysqlrn[b]出错信息[/b]rnThe last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.)rn at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:83)rn at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:80)rn at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:80)rn at org.springframework.orm.hibernate3.HibernateAccessor.convertJdbcAccessException(HibernateAccessor.java:424)rn at org.springframework.orm.hibernate3.HibernateAccessor.convertHibernateAccessException(HibernateAccessor.java:410)rn at org.springframework.orm.hibernate3.HibernateTemplate.doExecute(HibernateTemplate.java:412)rn at org.springframework.orm.hibernate3.HibernateTemplate.executeWithNativeSession(HibernateTemplate.java:375)rn at org.springframework.orm.hibernate3.HibernateTemplate.find(HibernateTemplate.java:913)rn at org.springframework.orm.hibernate3.HibernateTemplate.find(HibernateTemplate.java:905)rn at com.harmony.dao.common.impl.CommonDaoImpl.getMedias(CommonDaoImpl.java:29)rn at com.harmony.service.common.CommonService.getMedias(CommonService.java:19)rn at com.harmony.controller.common.CommonContraller.getMedia(CommonContraller.java:36)rn at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)rn at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)rn at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)rn at java.lang.reflect.Method.invoke(Method.java:606)rn at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215)rn at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)rn at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)rn at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:743)rn at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:672)rn at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:82)rn at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:919)rn at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:851)rn at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:953)rn at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:855)rn at javax.servlet.http.HttpServlet.service(HttpServlet.java:650)rn at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:829)rn at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)rn at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)rn at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)rn at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)rn at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)rn at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)rn at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)rn at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)rn at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505)rn at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)rn at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)rn at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956)rn at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)rn at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:423)rn at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1079)rn at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625)rn at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)rn at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)rn at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)rn at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)rn at java.lang.Thread.run(Thread.java:744)rnCaused by: org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Communications link failurernrnThe last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.)rn at org.apache.commons.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1549)rn at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1388)rn at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044)rn at org.springframework.orm.hibernate3.LocalDataSourceConnectionProvider.getConnection(LocalDataSourceConnectionProvider.java:83)rn at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:423)rn at org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:144)rn at org.hibernate.jdbc.AbstractBatcher.prepareQueryStatement(AbstractBatcher.java:139)rn at org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1547)rn at org.hibernate.loader.Loader.doQuery(Loader.java:673)rn at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:236)rn at org.hibernate.loader.Loader.doList(Loader.java:2213)rn at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2104)rn at org.hibernate.loader.Loader.list(Loader.java:2099)rn at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:378)rn at org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:338)rn at org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:172)rn at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1121)rn at org.hibernate.impl.QueryImpl.list(QueryImpl.java:79)rn at org.springframework.orm.hibernate3.HibernateTemplate$30.doInHibernate(HibernateTemplate.java:922)rn at org.springframework.orm.hibernate3.HibernateTemplate$30.doInHibernate(HibernateTemplate.java:913)rn at org.springframework.orm.hibernate3.HibernateTemplate.doExecute(HibernateTemplate.java:407)rn ... 43 morernCaused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failurern[b]数据源配置[/b]rnrn rn rn rn rn rnrn在网上找解决方法，试着更改my.cnf，没有用，大神解决一下

急！！The last packet sent successfully to the server was 0 milliseconds ago.的问题: 一个Flex+J2EE的项目，用的是eclipse3.4，Spring+Hibernate架构，mysql5.1数据库。rn项目是在实验室的台式机上开发的，笔记本只是在项目开始的时候配置好了环境，距现在已经将近一年了，现在要用笔记本进行演示，可是出现了这个问题：[code=Java]rn18:58:52,151 WARN SettingsFactory:137 - Could not obtain connection to query metadatarncom.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failurernrnThe last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.rn at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)rn at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)rn at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)rn at java.lang.reflect.Constructor.newInstance(Unknown Source)rn at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)rn at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)rn at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2214)rn at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:781)rn at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:46)rn at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)rn at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)rn at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)rn at java.lang.reflect.Constructor.newInstance(Unknown Source)rn at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)rn at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:352)rn at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:284)rn at java.sql.DriverManager.getConnection(Unknown Source)rn at java.sql.DriverManager.getConnection(Unknown Source)rn at org.hibernate.connection.DriverManagerConnectionProvider.getConnection(DriverManagerConnectionProvider.java:133)rn at org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:114)rn at org.hibernate.cfg.Configuration.buildSettingsInternal(Configuration.java:2163)rn at org.hibernate.cfg.Configuration.buildSettings(Configuration.java:2159)rn at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1383)rn at org.springframework.orm.hibernate3.LocalSessionFactoryBean.newSessionFactory(LocalSessionFactoryBean.java:855)rn at org.springframework.orm.hibernate3.LocalSessionFactoryBean.buildSessionFactory(LocalSessionFactoryBean.java:774)rn at org.springframework.orm.hibernate3.AbstractSessionFactoryBean.afterPropertiesSet(AbstractSessionFactoryBean.java:211)rn at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1460)rn at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1400)rn at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:513)rn at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:450)rn at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:290)rn at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)rn at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:287)rn at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:189)rn at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:545)rn at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:871)rn at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:423)rn at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:272)rn at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:196)rn at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:47)rn at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3830)rn at org.apache.catalina.core.StandardContext.start(StandardContext.java:4337)rn at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:791)rn at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:771)rn at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:525)rn at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:920)rn at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:883)rn at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:492)rn at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1138)rn at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311)rn at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117)rn at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053)rn at org.apache.catalina.core.StandardHost.start(StandardHost.java:719)rn at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)rn at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)rn at org.apache.catalina.core.StandardService.start(StandardService.java:516)rn at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)rn at org.apache.catalina.startup.Catalina.start(Catalina.java:566)rn at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)rn at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)rn at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)rn at java.lang.reflect.Method.invoke(Unknown Source)rn at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288)rn at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413)rnCaused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure[/code]rnrn在网上查了好久，大部分是说mysql的间隔访问时间太长导致的，但是，我的系统是前段时间重新安装的，数据库自然也是重新安装的，eclipse是绿色版的软件，里面直接集成的Flex，我在台式机上把eclipse文件夹拷贝到笔记本上，无论怎么调试也都是这个结果，求求各位路过的大神帮帮忙，看看到底是怎么回事啊rnmysql的url没有配置错误：jdbc:mysql://localhost/accountsystemrn我都快急死了，演示在即，希望大家帮帮忙吧

Tomcat报错last packet sent to the server was 0 ms ago: [img=http://hiphotos.baidu.com/yuanquanfeng/mpic/item/43620af4f5e7f14bddc474b5.jpg][/img]这个是什么问题啊，我重启Tomcat服务又可以运行了.rn网上说是localhost改127.0.0.1rn我都没有用localhost啊，rn我的项目是用struts+hibernate完成的rn

jdbc连接mysql数据库出现了问题: 我想做一些java数据库方面的程序,可在进行mysql驱动程序的连接时出现了问题?rn我下载的驱动名是:mysql-connector-java-3.1.13rn 在classpath中做了设置,E:\database\mysql-connector-java-3.1.13\mysql-connector-java-3.1.13-bin.jarrn写的测试程序是如下:(mysql数据库已经启动)rnimport java.sql.*; rnrnpublic class DBTest rnpublic static void main(String[] args) rnString driver = "org.git.mm.mysql.Driver";rnString url = "jdbc:mysql://localhost:3306/test";rnString user = ""; rnString password = ""; rntry rnClass.forName(driver); rnConnection conn = DriverManager.getConnection(url, user, password); rnif(!conn.isClosed()) rnSystem.out.println("数据库连接成功！"); rnconn.close(); rn rncatch(ClassNotFoundException e) rnSystem.out.println("找不到驱动程序"); rne.printStackTrace(); rn rncatch(SQLException e) rne.printStackTrace(); rn rn rnrn数据库名为:test,用户名和密码都为空.rn可是老是出现异常:Exception in thread "main" java.lang.NoClassDefFoundError: org/aspectj/lang/Signaturernmysql的版本是:5.0.22rn是不是数据库和驱动不兼容?别人的数据库和驱动都和我的一样,可能运行?rn是不是系统设置的问题?rn我先谢谢大家了?rn

jdbc连接mysql数据库出现错误: 一段简单的测试代码，但是出现错误！rn设置classpath=D:\Tomcat4.1\common\lib\mm.mysql-2.0.14-bin.jarrn代码：rnimport java.sql.*;rnpublic class database rn public static void Main(String[] args) rn Class.forName("org.gjt.mm.mysql.Driver").newInstance();rn java.sql.Connection conn;rn conn =rn DriverManager.getConnection(rn "jdbc:mysql:3306//localhost/new_db_1?user=root&password=12345678");rn rn rnrn不知道该怎么改正！谢谢！

JDBC连接MySQL数据库的流程及源码: JDBC连接MySQL数据库的流程第一步：导入jar驱动包 1.鼠标放在工程目录下的src目录上，点击右键，选择Build Path 2.在Build Path下选择configure Build Path... 3.点击选择Libraries,并在右边选择Add External JARs... 4.找到提前准备好的jdbc的jar包并点击打开 ...

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：rncom.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was 60,547,352 milliseconds ago. The last packet sent successfully to the server was 60,547,352 milliseconds ago. is longer than the server configured value of 'wait_timeout'. You should consider either expiring and/or testing connection validity before use in your application, increasing the server configured values for client timeouts, or using the Connector/J connection property 'autoReconnect=true' to avoid this problem.rnrn日志文件从这个地方开始往下只要是数据库操作就开始报错：rncom.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed.rnrn还有这个错：rnNo operations allowed after connection closed.rnrn再往下就是：rnjava.sql.SQLException: Operation not allowed after ResultSet closedrn at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1074)rn at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:988)rn at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:974)rn at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:919)rn at com.mysql.jdbc.ResultSetImpl.checkClosed(ResultSetImpl.java:803)rn at com.mysql.jdbc.ResultSetImpl.next(ResultSetImpl.java:6985)rn at com.dz.servlet.LoginServlet.service(LoginServlet.java:54)rn at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)rn at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269)rn at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)rn at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)rn at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:172)rn at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)rn at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)rn at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)rn at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:174)rn at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:845)rn at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:688)rn at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1315)rn at java.lang.Thread.run(Unknown Source)rnrnrn数据库版本：mysql 5.1.50rn服务器版本：tomcat5.5rn上面所有的错误重启tomcat后就没有了，但是，总不能让我每天都跑来重启服务器吧，所以这个问题还得解决，要想解决这个问题就得靠坛子里的大佬们了！！各位高手！请指点一下！！

JDBC连接MySQL报错Communications link failure due to underlying exception: 代码是这个样子的，求高手指点。rnpackage com.cn.jdbc;rnrnimport java.sql.DriverManager;rnrnimport java.sql.SQLException;rnrnimport com.mysql.jdbc.Connection;rnrnpublic class JDBC_Connection rn static String drivername = "com.mysql.jdbc.Driver";rn static String url = "jdbc:mysql://localhost:8080/zcl";rn static String username = "root";rn static String password = "root";rn staticrn try rn Class.forName(drivername);rn System.out.println("创建驱动成功");rn catch(ClassNotFoundException e)rn e.printStackTrace();rn rn rn public static Connection getConnection()rn Connection conn = null;rn rn tryrn conn = (Connection) DriverManager.getConnection(url,username,password);rn System.out.println("连接数据库成功访");rn catch(SQLException e)rn System.out.println("数据库连接失败！");rn e.printStackTrace();rn rn return conn;rn rn rn public static void main(String [] args)rn JDBC_Connection.getConnection();rn rnrn

myeclipse在连接mysql数据源的时候为何总显示the last packet sent successfully to the server was: 显示the last packet sent successfully to the server was 0 milliseconds agorn[img=https://img-bbs.csdn.net/upload/201509/21/1442815264_840941.png][/img][img=https://img-bbs.csdn.net/upload/201509/21/1442815273_647075.png][/img]rnrn各位大神求教了[img=https://forum.csdn.net/PointForum/ui/scripts/csdn/Plugin/001/face/9.gif][/img]因为我最近在学hibernate这个连不上好麻烦[img=https://forum.csdn.net/PointForum/ui/scripts/csdn/Plugin/001/face/9.gif][/img]再次感谢大家

用myeclipse链接MYSQL数据库的时候出现last packet sent to the server was 0 ms ago 请问怎么解决谢谢: connection URL jdbc:mysql:localhost:8080/testrnadd jar is mysql-connector-java-5.1.7-bin.jarrn其他设置正确请大家帮忙看看谢谢~~

解决JDBC连接MySQL数据库出现中文乱码的问题: 解决方案：在原有连接MySQL数据库的代码基础上添加：?useUnicode=true&amp;characterEncoding=utf-8 如：首先创建一张表：通过以下代码将userid为“1001”的“马芸”同学username修改为“任正肥”， public static void main(String[] args) throws ClassNotFoundExcept...

JDBC连接MySQL数据库时出现的乱码问题: JDBC 连接 MySQL数据库时出现的乱码问题，从六个方面来考虑：　　一、在编写页面时就出现了乱码　　二、在浏览器解析时出现了乱码　　三、由 JSP编译器在编译成 Servlet 时出现了乱码　　四、由数据库中的字段编码格式引起的乱码　　五、JDBC 连接 MySQL数据库时，没有拼接 useUnicode=true&characterEncoding=utf-8 的参数　　六、MySQL中的编码设

JDBC连接Mysql数据库出现NoClassDefFoundError错误: import java.sql.*;rnrnpublic class Mysqlrnrnpublic static void main(String[] args) rnrn try rn String driver = "org.gjt.mm.mysql.Driver";rn String url = "jdbc:mysql://localhost:3306/test";//server是数据库名rn String user = "root";rn String password = "";rn Connection conn = null;rn ResultSet rs = null;rn Statement stmt = null;rn Class.forName(driver).newInstance();rn conn = DriverManager.getConnection(url, user, password);rn stmt = conn.createStatement();rn rs = stmt.executeQuery("select *");rn while (rs.next()) rn System.out.println("" + rs.getInt(1) + "");rn System.out.println(":" + "");rn rn rs.close();rn conn.close();rn rn catch (Exception e) rn e.printStackTrace();rn rn rnrnrn如上源代码，编译可以通过，运行时出现NoClassDefFoundError错误，为什么？rnclasspath加了JDBC的驱动路径，也加了. 但还是有错，什么原因？

JDBC连接MySQL数据库出现的时区不一致的解决办法: 首先把我的jar包放出来给你们看一下，提前说一下，版本高的jar包约束太多，这就是你连接出现问题的原因，而配置两个时间要一致太繁琐了。所以，我给出如下解决办法。jar包我一开始下载的是官网最新的8.0.11版本的，结果，如下，说服务器程序和JDBC的时区时间不一致，连接失败。后来我在网上找了一大堆资料，最后自己琢磨勒一下，发现是因为我下载的jar包的版本太高了，会出现这种时区不一致的问题，因为新版...

JDBC连接MySQL数据库出现的错误及解决方法整理: 1. 在JDBC使用的时候有时候会出现java.sql.SQLException: The server time zone value ‘???ú±ê×??±??’ is unrecognized or represents…的错误，具体错误如下：注： 出现这个的原因是因为 mysql返回的时间总是有问题，比实际时间要早8小时。解决办法：在url后面加useUnicode=true&amp...

使用jdbc连接mysql数据库时出现的错误！！: IE运行时提示错误如下：（只是一个简单的struts程序）rntype Status reportrnrnmessage Servlet action is not availablernrndescription The requested resource (Servlet action is not available) is not available.rnrnrnrnrnstruts-config.xml中的项配置如下：rn rn rn rn rn rn rn rn rn rn rn rn rn rn rn rnrn如果在struts-config.xml中去掉配置，程序运行正常！！rn但如果加上配置项，程序会出现上面提示的错误！！！rnrn但是为了连接mysql数据库，必须这么配置啊，兄弟们帮助me解决问题啊！！rnrn非常感谢了！！ :)

MyEclipse连接mysql出错：Communications link failure: [size=11px][color=#FF0000]JAVA类代码：[/color][/size]import java.sql.*;rnrnpublic class TestJDBC rnrn public static void main(String[] args) rn ResultSet rs = null;rn Statement stmt = null;rn Connection conn = null;rn try rn Class.forName("com.mysql.jdbc.Driver");rn rn conn = DriverManager.getConnection("jdbc:mysql://localhost:8080/heng","root","root");rn stmt = conn.createStatement();rn rs = stmt.executeQuery("select * from ur");rn while(rs.next()) rn System.out.println(rs.getInt("userno"));rn System.out.println(rs.getString("username"));rn System.out.println(rs.getString("userpassword"));rn System.out.println(rs.getString("useraddress"));rn rn catch (ClassNotFoundException e) rn e.printStackTrace();rn catch (SQLException e) rn e.printStackTrace();rn finally rn try rn if(rs != null) rn rs.close();rn rs = null;rn rn if(stmt != null) rn stmt.close();rn stmt = null;rn rn if(conn != null) rn conn.close();rn conn = null;rn rn catch (SQLException e) rn e.printStackTrace();rn rn rn rnrnrnrn[color=#FF0000]报错：[/color]com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failurernrnThe last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.rn at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)rn at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)rn at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)rn at java.lang.reflect.Constructor.newInstance(Unknown Source)rn at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)rn at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1122)rn at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2260)rn at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:787)rn at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:49)rn at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)rn at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)rn at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)rn at java.lang.reflect.Constructor.newInstance(Unknown Source)rn at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)rn at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:357)rn at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)rn at java.sql.DriverManager.getConnection(Unknown Source)rn at java.sql.DriverManager.getConnection(Unknown Source)rn at TestJDBC.main(TestJDBC.java:12)rnCaused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failurernrnThe last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.rn at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)rn at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)rn at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)rn at java.lang.reflect.Constructor.newInstance(Unknown Source)rn at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)rn at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1122)rn at com.mysql.jdbc.MysqlIO.(MysqlIO.java:344)rn at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2181)rn ... 12 morernCaused by: java.net.ConnectException: Connection refused: connectrn at java.net.PlainSocketImpl.socketConnect(Native Method)rn at java.net.PlainSocketImpl.doConnect(Unknown Source)rn at java.net.PlainSocketImpl.connectToAddress(Unknown Source)rn at java.net.PlainSocketImpl.connect(Unknown Source)rn at java.net.SocksSocketImpl.connect(Unknown Source)rn at java.net.Socket.connect(Unknown Source)rn at java.net.Socket.connect(Unknown Source)rn at java.net.Socket.(Unknown Source)rn at java.net.Socket.(Unknown Source)rn at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:256)rn at com.mysql.jdbc.MysqlIO.(MysqlIO.java:293)rn ... 13 morern

maven项目出现中数据库Communications link failure: 错误:rn Build error for /eid-generator/pom.xml; org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate (Generate MyBatis Artifacts) on project eid-generator: Communications link failurernrnThe last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.rnrn[size=18px][color=#FF0000]POM.xml代码:[/color][/size]rnrn[code=html]rn 4.0.0rn rn eidrn eidrn 1.0.0rn rn eid-generatorrn eid-generatorrn jarrn eid-generatorrn ****平台-源码生成工具rnrn rn rn mysqlrn mysql-connector-javarn $version.mysqlrn rn rn org.mybatis.generatorrn mybatis-generator-corern $version.mybatis-generatorrn rn rn org.mybatisrn mybatisrn $version.mybatisrn rn rnrn rn rn rn src/main/javarn rn **/*Mapper.xmlrn rn rn rn src/main/resourcesrn rn **/*.xmlrn **/*.propertiesrn rn truern rn rn rn rn org.apache.maven.pluginsrn maven-compiler-pluginrn 2.3.2rn rn $version.jdkrn $version.jdkrn rn rn rn org.mybatis.generatorrn mybatis-generator-maven-pluginrn $version.mybatis-generatorrn rn src/main/resources/generatorConfig.xmlrn truern truern rn rn rn Generate MyBatis Artifactsrn rn generatern rn rn rn rn rn org.mybatis.generatorrn mybatis-generator-corern $version.mybatis-generatorrn rn rn mysqlrn mysql-connector-javarn $version.mysqlrn rn rn org.mybatisrn mybatisrn $version.mybatisrn rn rn rn rn rn rn rn org.eclipse.m2ern lifecycle-mappingrn 1.0.0rn rn rn rn copy-dependency pluginrn rn rn org.apache.maven.pluginsrn maven-dependency-pluginrn [1.0.0,)rn rn copy-dependenciesrn resourcesrn rn rn rn rn rn rn rn rn org.mybatis.generatorrn mybatis-generator-maven-pluginrn rn [$version.mybatis-generator,)rn rn generatern rn rn rn rn rn rn rn rn rn rn rn rn rn[/code]rnrn[size=18px]rn[color=#FF0000]rngeneratorConfig.xml代码:[/color][/size]rn[code=html]rnrnrn rn rnrn rn rn rn rnrn rn rnrn rn rn rn rnrn rn rn rn rn rnrn rn rn rnrn rn rn rnrn rnrn rn[/code]

链接MySql 出现 Communications link failure: 执行jar包，出现rnCommunications link failurernrnLast packet sent to the server was 0 ms ago.rn错误rnrn网上查了下，据说是链接打开一段时间没有处理超时，于是在my.cnf配置里面加上了timeout时间rnrn但是我只是在执行jar包的之后链接DB。rn并且链接DB取出数据后就close链接了。rnrn搞不懂为什么会出现这个问题。

jdbc连接mysql数据库: java连接mysql数据库，利用发射和泛型！

JDBC连接MySQL数据库: import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.Statement; public class JDBCDemo { public static void main(String[] args) throws Exception { ...

Jdbc连接mysql数据库: db.properties的配置文件 public class JdbcUtil { static String driver; static String url; static String user; static String pwd; //静态方法 static { try { // 通过类加载器来加载db.properties Inpu

JDBC连接MySQL数据库之一: 写了这么久代码，如果有人问你：你能不借助工具或资料，写一个jdbc连接mysql的测试程序吗，一点没有错误都没有哦？没写过的可能回答，没问题，这个很简单。但到了写完的时候，发现不是那么回事。呵呵 import java.sql.*; public class ConnMySQL{ public static void main(String[] args){ ...

JDBC如何连接mysql数据库: 我安装了mysql数据库,驱动也有了,classpath也设置好了,请哪位给如何连接的代码,谢谢

JDBC中连接MySQL数据库: package qddx.JDBC; import java.sql.*;public class JDBC_Connection { static String driverName = "com.mysql.jdbc.Driver";//驱动名 static String url="jdbc:mysql://localhost/bbs";//地址 static Strin

利用JDBC连接MySQL数据库: public static void main(String[] args){ ResultSet rs=null;//创建结果集 PreparedStatement pre=null;//创建执行sql语句对象 Connection conn=null;//创建数据库链接对象 try{ Class.f

JDBC连接mysql数据库: 1.1 jdbc编程步骤 1.加载数据库驱动 2.创建并获取数据库连接对象 3.创建jdbc statement对象 4.设置sql语句 5.设置sql语句中的参数（使用preprementStatement) 6.通过statement执行sql并获取结果 7.对sql执行结果进行解析处理 8.释放资源（resultSet、prepareStatement、connection) ----cod...

Java连接MySQL数据库（JDBC）: 今天恰巧用到了Java连接MySQL的问题，采取的是JDBC方式，看了网上一大堆，内容不少，但是都用不了，索性花了半天的时间研究了一下，方法提供给各位朋友。

jdbc连接mysql数据库的代码: 第一种：package dbutil; import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; public class DBUtil { static { try { //加载数据库驱动程序 Class.forName("com.mysql.jdbc....

JDBC连接MYSQL数据库的步骤: 使用JDBC步骤://使用 8.0及以后的jar包,这句就得换成com.mysql.cj.jdbc.DriverString driverClassName = "com.mysql.jdbc.Driver" ; //使用 8.0及以后的jar包,这句就得换成 jdbc:mysql://localhost:3306/mydb1?useSSL=true&amp;serverTimezone=GMT...

JDBC连接MySql数据库的问题: 我有一个jdbctest.jsp的程序，源码如下：rn rnrn运行后却出现如下错误：rnApache Tomcat/4.0.3 - HTTP Status 500 - Internal Server Errorrnrn--------------------------------------------------------------------------------rnrntype Exception reportrnrnmessage Internal Server Errorrnrndescription The server encountered an internal error (Internal Server Error) that prevented it from fulfilling this request.rnrnexception rnrnjavax.servlet.ServletException: org.gjt.mm.mysql.Driverrn at org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:463)rn at org.apache.jsp.jdbctest$jsp._jspService(jdbctest$jsp.java:72)rn at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:107)rn at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)rn at org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(JspServlet.java:202)rn at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:382)rn at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:474)rn at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)rn at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)rn at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)rn at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:243)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)rn at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)rn at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)rn at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:190)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)rn at org.apache.catalina.valves.CertificatesValve.invoke(CertificatesValve.java:246)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)rn at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)rn at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)rn at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2343)rn at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)rn at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:170)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)rn at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:170)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)rn at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:468)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)rn at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)rn at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)rn at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)rn at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)rn at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)rn at org.apache.catalina.connector.http.HttpProcessor.process(HttpProcessor.java:1012)rn at org.apache.catalina.connector.http.HttpProcessor.run(HttpProcessor.java:1107)rn at java.lang.Thread.run(Thread.java:536)rnrnrnroot cause rnrnjava.lang.ClassNotFoundException: org.gjt.mm.mysql.Driverrn at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1394)rn at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1243)rn at org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:198)rn at org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:132)rn at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:322)rn at java.lang.Class.forName0(Native Method)rn at java.lang.Class.forName(Class.java:130)rn at org.apache.jsp.jdbctest$jsp._jspService(jdbctest$jsp.java:61)rn at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:107)rn at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)rn at org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(JspServlet.java:202)rn at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:382)rn at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:474)rn at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)rn at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)rn at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)rn at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:243)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)rn at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)rn at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)rn at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:190)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)rn at org.apache.catalina.valves.CertificatesValve.invoke(CertificatesValve.java:246)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)rn at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)rn at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)rn at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2343)rn at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)rn at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:170)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)rn at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:170)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)rn at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:468)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)rn at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)rn at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)rn at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)rn at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)rn at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)rn at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)rn at org.apache.catalina.connector.http.HttpProcessor.process(HttpProcessor.java:1012)rn at org.apache.catalina.connector.http.HttpProcessor.run(HttpProcessor.java:1107)rn at java.lang.Thread.run(Thread.java:536)rnrn不知道是什么原因，请高手指教！

JDBC连接MYSQL数据库: 讲解使用JDBC连接MySQL数据库，为java开发人员必须掌握的技能！

JDBC连接Mysql数据库案例: JDBC连接Mysql数据库案例，共有两个表，分装好了JDBC连接的步骤代码

Java(JDBC)连接MySQL数据库: Java(JDBC)连接MySQL数据库工具： eclipse、MySQL 5.7 MySQL驱动程序文件 mysql-connector-java-5.1.8-bin.jar下载地址步骤：一、下载并安装MySQL，做好配置环境变量等准备工作二、创建Java Project，鼠标选中项目工程，右键点击 Build Path，选择 Configure Build Path，会跳 ...

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JDBC连接MySQl数据库方法: 欢迎使用Markdown编辑器写博客本Markdown编辑器使用StackEdit修改而来，用它写博客，将会带来全新的体验哦： Markdown和扩展Markdown简洁的语法代码块高亮图片链接和图片上传 LaTex数学公式 UML序列图和流程图离线写博客导入导出Markdown文件丰富的快捷键快捷键加粗 Ctrl + B 斜体 Ctrl + I 引用 Ctrl

jdbc连接mysql数据库 java: 在java中使用jdbc连接mysql数据库

JAVA：JDBC连接MySQL数据库: 一、下载mysql连接包,放到项目中 a) 首先要到mysql官网下载Connector/J地址是： http://www.mysql.com/downloads/connector/j/ b) 解压后的文件夹是： c) 拷贝到工程中： d) 鼠标右键：Add to Build Pat

配置jdbc连接mysql数据库: jdbc.properties jdbc.driver=com.mysql.jdbc.Driver jdbc.url=jdbc:mysql://127.0.0.1:3306/seckill?useUnicode=true&characterEncoding=utf8 jdbc.username=root jdbc.password=root 然后在spring-dao.xml引用jdbc.

Java JDBC 连接Mysql数据库: Java JDBC 连接Mysql数据库以下Code在同一个Package中。亲测可以进行CURD操作。JDBC的JdbcUtils类，例如：package JDBC_Java_Mysql;import java.sql.*;/** * Created by dhc on 17-5-2. */ public class JdbcUtils{ //获取数据库连接驱动 private

JDBC连接MySQL数据库步骤: JDBC连接数据库是java开发过程中访问数据库最基本的操作。作为一个java程序员，这应是默认会的基本技能。 1.将相关jar包导入到开发工具中（博主用的是eclipse）,实现基本的功能只需要mysql-connector-java-5.1.38-bin.jar 这一个就足够了； 2.在开发工具中建立java类，然后开始编写代码。 3.首先，既然

JDBC 连接MySQL数据库: package Connection; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; public class Te

jdbc连接MYSQL数据库: Constants类： package com.util; public class Constants { public static final String URL = "jdbc:mysql://localhost:3306/lover"; public static final String USERNAME = "root"; public sta

JDBC简介及连接MySQL数据库: JDBC简介 JDBC(Java DataBase Connectivity)可以让我们用相同的方式访问不同的数据库，它定义了一套标准的接口，即访问数据库的通用API。它是sun公司开发的一套数据库访问编程接口，由java语言编写完成。不同的数据库厂商根据自己数据库的特性去实现JDBC提供的这套接口。 JDBC具有很好的跨平台特性，使用JDBC编写的数据...

JDBC连接MySQL数据库之二: 接上一篇，不过这一篇主要是用来测试连接的。如果有人问你，我不需要查询结果，只要知道是不是连接上数据库，那下面code能派上用场了。 import java.sql.*; public class DBTest { public static void main(String[] args) { String driver = "com....

jdbc连接mysql数据库错误:: 我在C:\tomcat\common\lib放了:rnmm.mysql-2.0.4-bin.jarrnmysql-connector-java-2.0.14-bin.jarrnmysql-connector-java-3.0.9-stable-bin.jarrnmysql-connector-java-3.1.0-alpha-bin.jarrnrn错误信息如下:rnjava.sql.SQLException: Server configuration denies access to data sourcernrn请问:如何解决?

JDBC连接Mysql数据库: 博主使用的是mysql-connector-java6.0.6.jar架包百度云资源链接: https://pan.baidu.com/s/1tvS9pp7HV2JbtgSjD-Ga4Q 提取码: 55s5 下载后buildpath导入架包博主又导入内部架包test便于后期编写程序测试一、基础概念 JDBC（Java Data Base Connectivity,j...

jdbc驱动程序连接mysql数据库: 我在连接数据库是出现如下错误：rntest/lianjiedata.jsp:26: method 的不兼容类型。无法将 java.lang.String 转换为 java.util.Properties。rn Connection con = DriverManager.getConnection(url,user);rn请高手帮我看看！！先谢了！！！ rnrn

jdbc连接mysql数据库！: 我在连接数据库是出现如下错误：rntest/lianjiedata.jsp:26: method 的不兼容类型。无法将 java.lang.String 转换为 java.util.Properties。rn Connection con = DriverManager.getConnection(url,user);rn请高手帮我看看！！先谢了！！！

通过jdbc连接MySQL数据库: 使用jdbc提供的驱动进行连接数据库。首先需要从MySQL官网上下载jdbc的驱动，得到.jar文件，这就是我们需要的jdbc驱动。我们需要连接数据库，就首先需要我们电脑上有MySQL的数据库，并建立一个表，来存放数据。这里我自己建立一个名为mydb的表。建立好表后，我们就需要将我们下载的jar驱动包引入到我们的项目中，这里我们建立一个项目，在项目下建立一个lib文件夹，以放置我们项目需要的扩展

JDBC连接mySql数据库: JDBC连接mySql数据库要经历一下几个基本步骤：第一步：加载mysql驱动第二步：建立connection连接 第三步：创建数据库操作对象第四步：执行sql语句第五步：处理执行结果第六步：释放资源 import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; imp

JDBC实用技术(连接MySQL数据库): 内容：介绍MySQL的启动及连接，以及MySQL中的常用命令，并通过JDBC实例讲解如何去连接MySQL数据库产品：MySQL 5.0、Tomcat 技术：JDBC、Tomcat、JSP 难度： ★★☆☆☆

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JDBC连接MYSqL数据库模板: JDBC连接数据库模板 c3p0连接池 druid连接池 Spring jdbc 一、JDBC连接数据库主要步骤： 1.注册驱动 2.创建连接 3.操作数据 4.输出结果集 5.释放资源 A.单纯的数据库连接代码 import java.sql.*; public class MySqltest { public static void main(Stringargs[])th...

JDBC连接Mysql数据库java.lang.ClassNotFoundException: rn在2K下+JBuilder2005+ SQL server2K(版本5.0.2195 Service Pack 4 内部版本号 2195)rnpublic DbTest() rn driver = "com.microsoft.jdbc.sqlserver.SQLServerDriver";rn url = "jdbc:odbc:store_manager";rn user = "share";rn pwd = "share";rn init(); rn public void init() rn try rn Class.forName(driver);rn System.out.println("driver is ok");rn con = DriverManager.getConnection(url,user,pwd);rn System.out.println("conection is ok");rn sta = con.createStatement();rn ............rnclasspath我也设了ClassPath=D:\Program Files\Microsoft SQL Server 2000 Driver for JDBC\lib\msbasjar;D:\Program Files\Microsoft SQL Server 2000 Driver for JDBC\lib\mssqlserverar;D:\Program Files\Microsoft SQL Server 2000 Driver for JDBC\lib\msutil.jar;rn同时我也把三个包拷到\jre\lib\ext目录下跟WEB-INF\lib目录下了rn但为什么还是没有找到驱动???rn希望有高手请教一下!急~~~~~~~~~~~~~~~~

使用JDBC连接Mysql数据库: 完全参考http://www.runoob.com/java/java-mysql-connect.html，做了点修改。 package school_databases; import java.sql.*; public class ConnectToMysql { //JDBC驱动名及数据库URL static final String JDBC_DRIVER=&amp;quot;com.mysql....

JAVA JDBC连接MYSQL数据库: 连接MYSQL数据库 1.在项目中加载jdbc的jar包地址工具地址： https://blog.csdn.net/qq_37654578/article/details/87487503 package com.scem.db; import java.sql.Connection; import java.sql.DriverManager; import java.sql.Prepa...

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java -jdbc连接MySQL数据库: //记得引入驱动包！！！ package DatabaseT; import java.sql.*; import com.mysql.jdbc.Connection; public class MysqlDemo { static final String DB_URL = “jdbc:mysql://localhost:3306/ch09?useSSL=false”; ...

Java连接Mysql数据库——JDBC: java连接数据库时会随着mysql版本的变化而导致驱动配置方面有一些不同。暂时只用过mysql5.0左右的版本和mysql8.0.11。所以这里就只讲这两个版本，基本对应版本开头数字下的驱动基本大同小异。 mysql5.0 mysql5.0版本要用对应的驱动jar包，官网上、网上都有资源。 DBUtils类初始化驱动 package test; import java.sql.Con...

JDBC连接MySql数据库的常见错误: 当我用JDBC连接MySql数据库时，编译报了如下错误：错误1： Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI an...

jdbc问题：连接MySql数据库: 我想用JBuiler 连接MySql数据库rnrn但不知道该怎么用jdbcrnrn请求支援

JDBC连接MySQL数据库——案例: 采用MyEcplise+Navicat工具，通过JDBC连接MyEcplise和数据库，实现在MyEcplise中对数据库进行增删改查，要有点JAVA基础和MySQL基础。1、在数据库中创建表create table goddessmessage( id int primary key auto_increment, username

JDBC 连接 mysql数据库: 下面和大家分享一下简单的连接本地数据库的代码：这是连接DBUtil的代码：import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; public class DBUtil

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