已解决org.springframework.transaction.CannotCreateTransactionException: Could not open JDBC Connection

落日映苍穹つ 2023-09-26 19:03 138阅读 0赞

已解决org.springframework.transaction.CannotCreateTransactionException: Could not open JDBC Connection for异常的正确解决方法，亲测有效！！！

![在这里插入图片描述][a98eec5618e9416f8adf82755122428f.webp_pic_center]

#### 文章目录 ####

*   *  报错问题
     *  解决方法
     *  说明

### 报错问题 ###

粉丝群里面的一个小伙伴敲代码时发生了报错（当时他心里瞬间凉了一大截，跑来找我求助，然后顺利帮助他解决了，顺便记录一下希望可以帮助到更多遇到这个bug不会解决的小伙伴），报错信息如下：

![在这里插入图片描述][8f076594400b491986ca13af92b59b0c.jpeg_pic_center]  
SSM中本来可以连接数据库。部署上之后长时间不操作不能连接数据库

Message Request processing failed; nested exception is org.springframework.transaction.CannotCreateTransactionException: Could not open JDBC Connection for transaction; nested exception is com.mysql.cj.jdbc.exceptions.CommunicationsException: The last packet successfully received from the server was 43,541,996 milliseconds ago. The last packet sent successfully to the server was 43,541,997 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.

请求处理失败；嵌套异常是org.springframework.transaction.CannotCreateTransactionException：无法为事务打开jdbc连接；嵌套异常是com.mysql.cj.jdbc.exceptions.CommunicationsException：，最后一次从服务器成功接收数据包是43,541,996毫秒前。最后一次成功发送到服务器的数据包是43,541,997毫秒前。比服务器配置的值“WAIT\_TIMOUT”更长。在应用程序中使用之前，您应该考虑终止和/或测试连接有效性，增加服务器配置的客户端超时值，或者使用Connector/J Connection属性‘autorecnect=true’来避免此问题。

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.springframework.transaction.CannotCreateTransactionException: Could not open JDBC Connection for transaction; nested exception is com.mysql.cj.jdbc.exceptions.CommunicationsException: The last packet successfully received from the server was 43,541,996 milliseconds ago. The last packet sent successfully to the server was 43,541,997 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.
    	org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:978)
    	org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:857)
    	javax.servlet.http.HttpServlet.service(HttpServlet.java:635)
    	org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842)
    	javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
    	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    	org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
    	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    	org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
    	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    Root Cause
     
    org.springframework.transaction.CannotCreateTransactionException: Could not open JDBC Connection for transaction; nested exception is com.mysql.cj.jdbc.exceptions.CommunicationsException: The last packet successfully received from the server was 43,541,996 milliseconds ago. The last packet sent successfully to the server was 43,541,997 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.
    	org.springframework.jdbc.datasource.DataSourceTransactionManager.doBegin(DataSourceTransactionManager.java:245)
    	org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:373)
    	org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:427)
    	org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:276)
    	org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
    	org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    	org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
    	org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    	org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:655)
    	online.wenmeng.service.QQService$$EnhancerBySpringCGLIB$$2e799f6d.QQLogin(<generated>)
    	online.wenmeng.controler.QQControler.QQLogin(QQControler.java:33)
    	sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    	sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    	sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    	java.lang.reflect.Method.invoke(Method.java:498)
    	org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221)
    	org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137)
    	org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110)
    	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:777)
    	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:706)
    	org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
    	org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:943)
    	org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:877)
    	org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966)
    	org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:857)
    	javax.servlet.http.HttpServlet.service(HttpServlet.java:635)
    	org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842)
    	javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
    	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    	org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
    	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    	org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
    	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)

经过查询发现：

mysql超时设置的问题、如果连接闲置8小时 (8小时内没有进行数据库操作), mysql就会自动断开连接, 要重启tomcat.

### 解决方法 ###

解决方法如下

![在这里插入图片描述][51977e86019c4440b7d8465001aeac05.png]  
一、最简单方法

在使用数据库连接池的情况下，最好设置如下两个参数：autoReconnect=true&failOverReadOnly=false

jdbc:mysql://localhost:3306/test?user=root&password=&useUnicode=true&characterEncoding=gbk&autoReconnect=true&failOverReadOnly=false

在xml配置文件中，url中的&符号需要转义成&。比如在tomcat的server.xml中配置数据库连接池时，

mysql jdbc url样例如下：jdbc:mysql://localhost:3306/test?user=root&password=xxx&useUnicode=true&characterEncoding=gbk&autoReconnect=true&failOverReadOnly=false  
二、xml中进行修改

不用hibernate的话, connection url加参数: autoReconnect=true 
        用hibernate的话, 加如下属性: 
            <property name="connection.autoReconnect">true</property> 
            <property name="connection.autoReconnectForPools">true</property> 
            <property name="connection.is-connection-validation-required">true</property> 
        要是还用c3p0连接池: 
            <property name="hibernate.c3p0.acquire_increment">1</property> 
            <property name="hibernate.c3p0.idle_test_period">0</property> 
            <property name="hibernate.c3p0.timeout">0</property> 
            <property name="hibernate.c3p0.validate">true</property>

三、较为复杂但适合服务器中多项目

请移步：——> 修改MySQL连接超时时间  
几个重要的参数，如下表所示：

![在这里插入图片描述][bde0abd28a4f4331a4b3864c531b5914.png]

### 说明 ###

解决方法也是我在网上找的，如有侵权联系我删除

[a98eec5618e9416f8adf82755122428f.webp_pic_center]: https://img-blog.csdnimg.cn/a98eec5618e9416f8adf82755122428f.webp#pic_center
[8f076594400b491986ca13af92b59b0c.jpeg_pic_center]: https://img-blog.csdnimg.cn/8f076594400b491986ca13af92b59b0c.jpeg#pic_center
[51977e86019c4440b7d8465001aeac05.png]: https://img-blog.csdnimg.cn/51977e86019c4440b7d8465001aeac05.png
[bde0abd28a4f4331a4b3864c531b5914.png]: https://img-blog.csdnimg.cn/bde0abd28a4f4331a4b3864c531b5914.png