Spring 中 C3p0 connection pooling 连接池的配置

在Spring项目中使用C3p0-JDBC3ConnectionandStatementPooling

C3p0Document在http://www.mchange.com/projects/c3p0/index.html

Spring的DataSourcebean定义如下,把可变的变量抽出放在jdbc.propertiesfile中,方便修改jdbc.propertiesfile只要放在当前项目的classes路径下,或放在Tomcat的Shared/classes下,Spring就可以找到

<bean id="propertyConfigurer"
        class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
        <property name="location">
            <value>classpath:jdbc.properties</value>
        </property>
    </bean>

<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="com.mysql.jdbc.Driver" />
        <property name="jdbcUrl" value="${jdbc.url}" />
        <property name="user" value="${jdbc.username}" />
        <property name="password" value="${jdbc.password}" />
        <property name="autoCommitOnClose" value="true"/>
        <property name="checkoutTimeout" value="${cpool.checkoutTimeout}"/>
        <property name="initialPoolSize" value="${cpool.minPoolSize}"/>
        <property name="minPoolSize" value="${cpool.minPoolSize}"/>
        <property name="maxPoolSize" value="${cpool.maxPoolSize}"/>
        <property name="maxIdleTime" value="${cpool.maxIdleTime}"/>
        <property name="acquireIncrement" value="${cpool.acquireIncrement}"/>
        <property name="maxIdleTimeExcessConnections" value="${cpool.maxIdleTimeExcessConnections}"/>
    </bean>

jdbc.properties
 # Database URL
jdbc.url=jdbc:mysql://192.168.0.25"3306/db

# Database login information
jdbc.username=root
jdbc.password=

# Time to wait for an open connection before timing out
# (in milliseconds)
cpool.checkoutTimeout=5000

# Connection pool size
cpool.minPoolSize=5
cpool.maxPoolSize=40

# How long to keep unused connections around(in seconds)
# Note: MySQL times out idle connections after 8 hours(28,800 seconds)
# so ensure this value is below MySQL idle timeout
cpool.maxIdleTime=25200

# How long to hang on to excess unused connections after traffic spike
# (in seconds)
cpool.maxIdleTimeExcessConnections=1800

# Acquiring new connections is slow, so eagerly retrieve extra connections
# when current pool size is reached
cpool.acquireIncrement=5