2

我在互联网上阅读了很多关于这个问题的文章，但似乎没有一个明确的解决方案。请有人给我一个明确的答案，说明我为什么会出现数据库超时。该应用程序是托管在 Tomcat 5.5 服务器上的 GWT 应用程序。我使用spring，并在applicationContext.xml中创建了会话工厂，如下所示

<bean id="sessionFactory"
      class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
    <property name="hibernateProperties">
        <props>
            <prop key="hibernate.dialect">${connection.dialect}</prop>
            <prop key="hibernate.connection.username">${connection.username}</prop>
            <prop key="hibernate.connection.password">${connection.password}</prop>
            <prop key="hibernate.connection.url">${connection.url}</prop>
            <prop key="hibernate.connection.driver_class">${connection.driver.class}</prop>
            <prop key="hibernate.show_sql">${show.sql}</prop>
            <prop key="hibernate.hbm2ddl.auto">update</prop>
            <prop key="hibernate.c3p0.min_size">5</prop>
            <prop key="hibernate.c3p0.max_size">20</prop>
            <prop key="hibernate.c3p0.timeout">1800</prop>
            <prop key="hibernate.c3p0.max_statements">50</prop>
            <prop key="hibernate.c3p0.idle_test_period">300</prop>
        </props>
    </property>
    <property name="annotatedClasses">
        <list>
            <value>za.co.xxxx.traintrack.server.model.Answer</value>
            <value>za.co.xxxx.traintrack.server.model.Company</value>
            <value>za.co.xxxx.traintrack.server.model.CompanyRegion</value>
            <value>za.co.xxxx.traintrack.server.model.Merchant</value>
            <value>za.co.xxxx.traintrack.server.model.Module</value>
            <value>za.co.xxxx.traintrack.server.model.Question</value>
            <value>za.co.xxxx.traintrack.server.model.User</value>
            <value>za.co.xxxx.traintrack.server.model.CompletedModule</value>
        </list>
    </property>
</bean>

<bean id="dao" class="za.co.xxxx.traintrack.server.DAO">
    <property name="sessionFactory" ref="sessionFactory"/>
    <property name="adminUsername" value="${admin.user.name}"/>
    <property name="adminPassword" value="${admin.user.password}"/>
    <property name="godUsername" value="${god.user.name}"/>
    <property name="godPassword" value="${god.user.password}"/>
</bean>

直到第二天一切正常：

INFO   | jvm 1    | 2010/06/15 14:42:27 | 2010-06-15 18:42:27,804 WARN 
[JDBCExceptionReporter] : SQL Error: 0, SQLState: 08S01
INFO   | jvm 1    | 2010/06/15 14:42:27 | 2010-06-15 18:42:27,821 ERROR 
[JDBCExceptionReporter] : The last packet successfully received from the server 
was 38729 seconds ago.The last packet sent successfully to the server was 38729
seconds ago, which  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.
INFO   | jvm 1    | 2010/06/15 14:42:27 | Jun 15, 2010 6:42:27 PM 
org.apache.catalina.core.ApplicationContext log
INFO   | jvm 1    | 2010/06/15 14:42:27 | SEVERE: Exception while dispatching
incoming RPC call

我已经阅读了很多不同的东西（没有一个有效），请帮助

4

2 回答 2

1

看看这个链接http://www.databasesandlife.com/automatic-reconnect-from-hibernate-to-mysql/

 In “hibernate.cfg.xml”:

<!-- hibernate.cfg.xml -->
<property name="c3p0.min_size">5</property>
<property name="c3p0.max_size">20</property>
<property name="c3p0.timeout">1800</property>
<property name="c3p0.max_statements">50</property>
<property name="connection.provider_class">
   org.hibernate.connection.C3P0ConnectionProvider</property>
<!-- no "connection.pool_size" entry! -->

然后创建一个文件“c3p0.properties”，该文件必须位于类路径的根目录中（即无法为应用程序的特定部分覆盖它）：

# c3p0.properties
c3p0.testConnectionOnCheckout=true
于 2010-06-15T19:49:13.180 回答
0

Romain，我没有 hibernate.cfg.xml（全部在 applicationContext.XML 中完成）

c3p0.properties

c3p0.testConnectionOnCheckout=true

应用程序上下文.xml

<?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/context
           http://www.springframework.org/schema/context/spring-context-2.5.xsd
           http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
           http://www.springframework.org/schema/tx
           http://www.springframework.org/schema/tx/spring-tx-2.0.xsd
           ">

    <context:annotation-config/>

    <context:component-scan base-package="za.co.cmsoftware.traintrack.server"/>

    <!-- Application properties -->
    <bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
        <property name="locations">
            <list>
                <value>file:${user.dir}/@propertiesFile@</value>
            </list>
        </property>
    </bean>

    <bean id="sessionFactory"
          class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">${connection.dialect}</prop>
                <prop key="hibernate.connection.username">${connection.username}</prop>
                <prop key="hibernate.connection.password">${connection.password}</prop>
                <prop key="hibernate.connection.url">${connection.url}</prop>
                <prop key="hibernate.connection.driver_class">${connection.driver.class}</prop>
                <prop key="hibernate.show_sql">${show.sql}</prop>
                <prop key="hibernate.hbm2ddl.auto">update</prop>
                <prop key="hibernate.c3p0.min_size">5</prop>
                <prop key="hibernate.c3p0.max_size">20</prop>
                <prop key="hibernate.c3p0.timeout">1800</prop>
                <prop key="hibernate.c3p0.max_statements">50</prop>
                <prop key="hibernate.c3p0.idle_test_period">300</prop>
                <prop key="connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</prop>
            </props>
        </property>
        <property name="annotatedClasses">
            <list>
                <value>za.co.xxxx.traintrack.server.model.Answer</value>
                <value>za.co.xxxx.traintrack.server.model.Company</value>
                <value>za.co.xxxx.traintrack.server.model.CompanyRegion</value>
                <value>za.co.xxxx.traintrack.server.model.Merchant</value>
                <value>za.co.xxxx.traintrack.server.model.Module</value>
                <value>za.co.xxxx.traintrack.server.model.Question</value>
                <value>za.co.xxxx.traintrack.server.model.User</value>
                <value>za.co.xxxx.traintrack.server.model.CompletedModule</value>
            </list>
        </property>
    </bean>

    <bean id="dao" class="za.co.xxxx.traintrack.server.DAO">
        <property name="sessionFactory" ref="sessionFactory"/>
        <property name="adminUsername" value="${admin.user.name}"/>
        <property name="adminPassword" value="${admin.user.password}"/>
        <property name="godUsername" value="${god.user.name}"/>
        <property name="godPassword" value="${god.user.password}"/>
    </bean>

    <bean id="transactionManager"
          class="org.springframework.orm.hibernate3.HibernateTransactionManager">
        <property name="sessionFactory">
            <ref local="sessionFactory"/>
        </property>
    </bean>

    <!-- enable the configuration of transactional behavior based on annotations -->
    <tx:annotation-driven transaction-manager="transactionManager"/>

</beans>
于 2010-06-20T19:54:37.733 回答