org.springframework.transaction.CannotCreateTransactionException: Could not open JDBC Connection for

野性酷女 2021-09-21 15:38 332阅读 0赞

> 博客来源：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。

## 具体报错信息：  ##

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：  ##

> 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**&amp**;。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**&amp**;password=xxx**&amp**;useUnicode=true**&amp**;characterEncoding=gbk**&amp**;autoReconnect=true**&amp**;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（还没写好，先百度吧，后续更新）

**几个重要的参数，如下表所示：**

<table> 
 <tbody> 
  <tr> 
   <td><strong>参数名称</strong></td> 
   <td><strong>参数说明</strong></td> 
   <td><strong>缺省值</strong></td> 
   <td><strong>最低版本要求</strong></td> 
  </tr> 
  <tr> 
   <td>user</td> 
   <td>数据库用户名（用于连接数据库）</td> 
   <td>&nbsp;</td> 
   <td>所有版本</td> 
  </tr> 
  <tr> 
   <td>password</td> 
   <td>用户密码（用于连接数据库）</td> 
   <td>&nbsp;</td> 
   <td>所有版本</td> 
  </tr> 
  <tr> 
   <td>useUnicode</td> 
   <td>是否使用Unicode字符集，如果参数characterEncoding设置为gb2312或gbk，本参数值必须设置为true</td> 
   <td>false</td> 
   <td>1.1g</td> 
  </tr> 
  <tr> 
   <td>characterEncoding</td> 
   <td>当useUnicode设置为true时，指定字符编码。比如可设置为gb2312或gbk</td> 
   <td>false</td> 
   <td>1.1g</td> 
  </tr> 
  <tr> 
   <td>autoReconnect</td> 
   <td>当数据库连接异常中断时，是否自动重新连接？</td> 
   <td>false</td> 
   <td>1.1</td> 
  </tr> 
  <tr> 
   <td>autoReconnectForPools</td> 
   <td>是否使用针对数据库连接池的重连策略</td> 
   <td>false</td> 
   <td>3.1.3</td> 
  </tr> 
  <tr> 
   <td>failOverReadOnly</td> 
   <td>自动重连成功后，连接是否设置为只读？</td> 
   <td>true</td> 
   <td>3.0.12</td> 
  </tr> 
  <tr> 
   <td>maxReconnects</td> 
   <td>autoReconnect设置为true时，重试连接的次数</td> 
   <td>3</td> 
   <td>1.1</td> 
  </tr> 
  <tr> 
   <td>initialTimeout</td> 
   <td>autoReconnect设置为true时，两次重连之间的时间间隔，单位：秒</td> 
   <td>2</td> 
   <td>1.1</td> 
  </tr> 
  <tr> 
   <td>connectTimeout</td> 
   <td>和数据库服务器建立socket连接时的超时，单位：毫秒。 0表示永不超时，适用于JDK 1.4及更高版本</td> 
   <td>0</td> 
   <td>3.0.1</td> 
  </tr> 
  <tr> 
   <td>socketTimeout</td> 
   <td>socket操作（读写）超时，单位：毫秒。 0表示永不超时</td> 
   <td>0</td> 
   <td>3.0.1</td> 
  </tr> 
 </tbody> 
</table>