jdbc连接数据库的com.mysql.jdbc.CommunicationsException问题 10C
    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.<init>(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.<init>(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)

5个回答

连接mysql方式,必须先添加mysql驱动jar包:
public Connection getConnection() throws SQLException {
if (connection == null) {
String url = "jdbc:mysql://localhost:3306/mysql";
Properties props = new Properties();
props.setProperty("user", user);
props.setProperty("password", password);
try {
Class.forName("com.mysql.jdbc.Driver");
connection = DriverManager.getConnection(url, props);
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
return connection;

MYNAMEQI
赚他一个亿 解决了吗?我的是安卓用jdbc连接的 Mysql,在电脑上的 虚拟机是可以实现的,但是换成真机就会包这个错误
大约 2 年之前 回复
Jackie_gdut
Jackie 仔 回复qq_28037587: 首先url应该是这样的格式"jdbc:mysql://localhost:3306/mysql",你上面的报错是url连接不上,还有就是驱动问题,"com.mysql.jdbc.Driver"这个驱动名对应的jar包应该是这样的"mysql-connector-java-5.1.30.jar"。还有就是ODBC现在是过时的了,现在都用JDBC
2 年多之前 回复
qq_28037587
qq_28037587 不好意思,上面没有说全,就是jdbc方式每个步骤都检查过了,jar包也添加了,但是仍然报的这个错误
2 年多之前 回复

看那看jar包版本对不对,可能是版本冲突,楼主试一下!

是不是你本机网卡ipv4和ipv6的问题, 启动参数里面添加 -Djava.net.preferIPv4Stack=true 试试,

数据库没有配置好,url设置哪里

你把localhost换成127.0.0.1试试

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Could not get JDBC Connection; com.mysql.cj.jdbc.Driver?
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org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99) at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:267) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207) at com.sun.proxy.$Proxy34.getItemById(Unknown Source) at com.taotao.controller.ItemController.getItemById(ItemController.java:27) 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:498) at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:777) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:706) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:943) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:877) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966) at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:857) at javax.servlet.http.HttpServlet.service(HttpServlet.java:621) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842) at javax.servlet.http.HttpServlet.service(HttpServlet.java:728) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748) db.properties配置为 jdbc.driver=com.mysql.cj.jdbc.Driver jdbc.url=jdbc:mysql://localhost:3306/taotao?useSSL=false&serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=UTF8 jdbc.username=root jdbc.password=123 连接池配置 <context:property-placeholder location="classpath:resource/db.properties" /> <!-- 数据库连接池 --> <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" destroy-method="close"> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <property name="driverClassName" value="${jdbc.driver}" /> <!-- <property name="maxActive" value="10" /> <property name="minIdle" value="5" /> --> </bean> <!-- 让spring管理sqlsessionfactory 使用mybatis和spring整合包中的 --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 加载mybatis的全局配置文件 --> <property name="configLocation" value="classpath:mybatis/SqlMapConfig.xml" /> <!-- 数据库连接池 --> <property name="dataSource" ref="dataSource" /> </bean> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="com.taotao.mapper" /> </bean>
jdbc连接数据库 class.froname
try{ **Class.forName("com.mysql.jdbc.Driver");** conn=DriverManager.getConnection(url,username,password); System.out.println("连接数据库成功"); }catch(Exception e){ e.printStackTrace(); System.out.println("建立数据库发生错误!"); }finally{ return conn; } class.forname这句话,不要好像也可以运行啊,这话什么意思,可以不要吗
Eclipse用JDBC连接不上MYSQL
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,提示错误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:408) at com.mysql.jdbc.Util.getInstance(Util.java:383) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1023) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:997) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:983) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1111) at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2494) at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2527) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2309) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:834) at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46) 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:408) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:419) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:344) at java.sql.DriverManager.getConnection(Unknown Source) at java.sql.DriverManager.getConnection(Unknown Source)请知道的大神解答一下小弟
在线等!!!linux服务器连接mysql5.7数据库报错 Could not get JDBC Connection; nested exception is com.alibaba.druid.pool.GetConnectionTimeoutException
以下是服务器上的报错代码 ![图片说明](https://img-ask.csdn.net/upload/201911/12/1573526989_375593.png) ``` >org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 1000, active 0, maxActive 500, creating 1 ``` 问题就是出在这里. 1,本地项目正常启动,无任何报错,数据库连接正常(使用的都是linux上面的数据库). ![图片说明](https://img-ask.csdn.net/upload/201911/12/1573527132_402324.png) 2,数据库工具使用无任何问题 ![图片说明](https://img-ask.csdn.net/upload/201911/12/1573527246_699888.png) 3,下面放出jdbc配置文件和spring配置文件 ``` jdbc.driverClassName=com.mysql.jdbc.Driver jdbc.url=jdbc:mysql://..XXXXXX.:/XXXXXX?useUnicode=true&characterEncoding=UTF-8&useSSL=false jdbc.username=xxxx jdbc.password=xxxxx jdbc.filters=stat jdbc.maxActive=500 jdbc.initialSize=1 jdbc.maxWait=1000 jdbc.minIdle=10 jdbc.maxIdle=15 jdbc.timeBetweenEvictionRunsMillis=60000 jdbc.minEvictableIdleTimeMillis=300000 jdbc.validationQuery=SELECT 'x' jdbc.testWhileIdle=true jdbc.testOnBorrow=false jdbc.testOnReturn=false jdbc.maxOpenPreparedStatements=20 jdbc.removeAbandoned=true jdbc.removeAbandonedTimeout=180 jdbc.logAbandoned=true ``` spring 配置 ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd"> <!-- 扫描service包下所有使用注解的类型 --> <context:component-scan base-package="com.yoFish.service"/> <!-- 配置数据库相关参数properties的属性:${url} --> <context:property-placeholder location="classpath:jdbc.properties"/> <!-- 阿里 druid 数据库连接池 --> <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" destroy-method="close"> <!-- 数据库基本信息配置 --> <property name="driverClassName" value="${jdbc.driverClassName}"/> <property name="url" value="${jdbc.url}"/> <property name="username" value="${jdbc.username}"/> <property name="password" value="${jdbc.password}"/> <property name="filters" value="${jdbc.filters}"/> <!-- 最大并发连接数 --> <property name="maxActive" value="${jdbc.maxActive}"/> <!-- 初始化连接数量 --> <property name="initialSize" value="${jdbc.initialSize}"/> <!-- 配置获取连接等待超时的时间 --> <property name="maxWait" value="${jdbc.maxWait}"/> <!-- 最小空闲连接数 --> <property name="minIdle" value="${jdbc.minIdle}"/> <!-- 最大空闲连接数 --> <property name="maxIdle" value="${jdbc.maxIdle}"/> <!-- 配置间隔多久才进行一次检测,检测需要关闭的空闲连接,单位是毫秒 --> <property name="timeBetweenEvictionRunsMillis" value="${jdbc.timeBetweenEvictionRunsMillis}"/> <!-- 配置一个连接在池中最小生存的时间,单位是毫秒 --> <property name="minEvictableIdleTimeMillis" value="${jdbc.minEvictableIdleTimeMillis}"/> <property name="validationQuery" value="${jdbc.validationQuery}"/> <property name="testWhileIdle" value="${jdbc.testWhileIdle}"/> <property name="testOnBorrow" value="${jdbc.testOnBorrow}"/> <property name="testOnReturn" value="${jdbc.testOnReturn}"/> <property name="maxOpenPreparedStatements" value="${jdbc.maxOpenPreparedStatements}"/> <!-- 超过时间限制是否回收 --> <property name="removeAbandoned" value="${jdbc.removeAbandoned}"/> <!-- 1800 秒,也就是 30 分钟 --> <property name="removeAbandonedTimeout" value="${jdbc.removeAbandonedTimeout}"/> <!-- 关闭 abanded 连接时输出错误日志 --> <property name="logAbandoned" value="${jdbc.logAbandoned}"/> </bean> <!-- 配置SqlSessionFactory对象 --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 注入数据库连接池 --> <property name="dataSource" ref="dataSource"/> <!-- 扫描model包 使用别名 --> <property name="typeAliasesPackage" value="com.yoFish.model"/> <!-- 扫描sql配置文件:mapper需要的xml文件 --> <property name="mapperLocations" value="classpath:mapper/*.xml"/> </bean> <!-- 配置扫描Dao接口包,动态实现Dao接口,注入到spring容器中 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <!-- 注入sqlSessionFactory --> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/> <!-- 给出需要扫描Dao接口包 --> <property name="basePackage" value="com.yoFish.dao"/> </bean> <!-- 配置事务管理器 --> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <!-- 注入数据库连接池 --> <property name="dataSource" ref="dataSource"/> </bean> <!-- 配置基于注解的声明式事务 --> <tx:annotation-driven transaction-manager="transactionManager"/> </beans> ``` 这个问题搞了很久了,主要就是不知道问题在哪,本地真的是没有任何问题,很多方式我也试过了.很头疼,求大佬帮忙解决
Java连接数据库连接不上出现时区错误代码都没问题,Mysq server版本也没问题
连接数据库连接不上,代码找不到错误,说时区错误,Mysql server 5.5版本的也没问题,在别人电脑也不能运行 详细错误, Exception in thread "main" java.sql.SQLException: The server time zone value '?й???????' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support. at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:129) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:73) at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:76) 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:199) at java.sql.DriverManager.getConnection(Unknown Source) at java.sql.DriverManager.getConnection(Unknown Source) at com.mysql.cj.jdbc.admin.TimezoneDump.main(TimezoneDump.java:70) Caused by: com.mysql.cj.exceptions.InvalidConnectionAttributeException: The server time zone value '?й???????' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support. 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.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61) at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:85) at com.mysql.cj.util.TimeUtil.getCanonicalTimezone(TimeUtil.java:132) at com.mysql.cj.protocol.a.NativeProtocol.configureTimezone(NativeProtocol.java:2121) at com.mysql.cj.protocol.a.NativeProtocol.initServerSession(NativeProtocol.java:2145) at com.mysql.cj.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:1310) at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:967) at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:826) ... 6 more
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)
linux执行jar包报Caused by: com.mysql.cj.exceptions.CJException: Access denied for user 'root'@'root' (using password: YES)错误
我用idea创建一个spring boot项目本地执行application可以运行程序。 但是项目打成jar包后放入linux中用 java -jar执行报错,报错情况如下: [ERROR] 2019-09-28 13:10:36,293 method:com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:1846) create connection error java.sql.SQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up. at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:110) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:73) at com.mysql.cj.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:897) at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:822) at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:447) at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:237) at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:199) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1375) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1431) at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:1844) Caused by: com.mysql.cj.exceptions.CJException: Access denied for user 'root'@'root' (using password: YES) at sun.reflect.GeneratedConstructorAccessor34.newInstance(Unknown Source) 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.createException(ExceptionFactory.java:129) at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:795) at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:720) at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:688) at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:130) at com.mysql.cj.protocol.a.NativeAuthenticationProvider.proceedHandshakeWithPluggableAuthentication(NativeAuthenticationProvider.java:540) at com.mysql.cj.protocol.a.NativeAuthenticationProvider.connect(NativeAuthenticationProvider.java:202) at com.mysql.cj.protocol.a.NativeProtocol.connect(NativeProtocol.java:1348) at com.mysql.cj.NativeSession.connect(NativeSession.java:163) at com.mysql.cj.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:841) ... 7 more [ERROR] 2019-09-28 13:10:40,298 method:com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:1846) create connection error java.sql.SQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up. at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:110) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:73) at com.mysql.cj.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:897) at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:822) at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:447) at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:237) at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:199) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1375) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1431) at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:1844) Caused by: com.mysql.cj.exceptions.CJException: Access denied for user 'root'@'root' (using password: YES) at sun.reflect.GeneratedConstructorAccessor34.newInstance(Unknown Source) 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.createException(ExceptionFactory.java:129) at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:795) at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:720) at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:688) at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:130) at com.mysql.cj.protocol.a.NativeAuthenticationProvider.proceedHandshakeWithPluggableAuthentication(NativeAuthenticationProvider.java:540) at com.mysql.cj.protocol.a.NativeAuthenticationProvider.connect(NativeAuthenticationProvider.java:202) at com.mysql.cj.protocol.a.NativeProtocol.connect(NativeProtocol.java:1348) at com.mysql.cj.NativeSession.connect(NativeSession.java:163) at com.mysql.cj.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:841) ... 7 more
mysql连接出错,sqlyog可以连接数据库,jdbc出错
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