部分代码来自网上，黄绿色的字体就是c3p0 sqlserver2008连接池的设置，其中特别注意的是''driverClass','jdbcUrl','user','password'区分大小写,并且要把c3p0-0.9.1-pre6.jar放到classpath中;

1.sqlserver2008

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-2.0.xsd">

<!-- Hibernate SessionFactory -->
<bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionfactorybean">
<property name="dataSource">
<ref local="dataSource" />
</property>
<property name="mappingResources">
<list>
<value>com/oy/image/model/LoginUser.hbm.xml</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.sqlServerDialect</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.generate_statistics">true</prop>
<prop key="hibernate.connection.release_mode">auto</prop>
<prop key="hibernate.autoReconnect">true</prop>
</props>
</property>
</bean>

<bean id="dataSource"
class="com.mchange.v2.c3p0.ComboPooledDataSource"
destroy-method="close">
<property name="driverClass">
<value>com.microsoft.jdbc.sqlserver.sqlServerDriver</value>
</property>
<property name="jdbcUrl">
<value>jdbc:microsoft:sqlserver://localhost:1433;databaseName=users</value>
</property>
<property name="user">
<value>bruce</value>
</property>
<property name="password">
<value>bruce</value>
</property>

<!--连接池中保留的最小连接数。-->
<property name="minPoolSize">
<value>5</value>
</property>

<!--连接池中保留的最大连接数。Default: 15 -->
<property name="maxPoolSize">
<value>30</value>
</property>

<!--初始化时获取的连接数，取值应在minPoolSize与maxPoolSize之间。Default: 3 -->
<property name="initialPoolSize">
<value>10</value>
</property>

<!--最大空闲时间,60秒内未使用则连接被丢弃。若为0则永不丢弃。Default: 0 -->
<property name="maxIdleTime">
<value>60</value>
</property>

<!--当连接池中的连接耗尽的时候c3p0一次同时获取的连接数。Default: 3 -->
<property name="acquireIncrement">
<value>5</value>
</property>

<!--JDBC的标准参数，用以控制数据源内加载的PreparedStatements数量。但由于预缓存的statements
属于单个connection而不是整个连接池。所以设置这个参数需要考虑到多方面的因素。
如果maxStatements与maxStatementsPerConnection均为0，则缓存被关闭。Default: 0-->
<property name="maxStatements">
<value>0</value>
</property>

<!--每60秒检查所有连接池中的空闲连接。Default: 0 -->
<property name="idleConnectionTestPeriod">
<value>60</value>
</property>

<!--定义在从数据库获取新连接失败后重复尝试的次数。Default: 30 -->
<property name="acquireRetryAttempts">
<value>30</value>
</property>

<!--获取连接失败将会引起所有等待连接池来获取连接的线程抛出异常。但是数据源仍有效
保留，并在下次调用getConnection()的时候继续尝试获取连接。如果设为true，那么在尝试
获取连接失败后该数据源将申明已断开并永久关闭。Default: false-->
<property name="breakAfterAcquireFailure">
<value>true</value>
</property>

<!--因性能消耗大请只在需要的时候使用它。如果设为true那么在每个connection提交的
时候都将校验其有效性。建议使用idleConnectionTestPeriod或automaticTestTable
等方法来提升连接测试的性能。Default: false -->
<property name="testConnectionOnCheckout">
<value>false</value>
</property>
</bean>
<bean id="imageDao" name="imageDao"
class="com.oy.image.dao.hibernate.ImageDaoHibernate" abstract="false"
lazy-init="default" autowire="default" dependency-check="default">
<property name="sessionFactory">
<ref bean="sessionFactory" />
</property>
</bean>
<bean id="imageManager" name="imageManager"
class="com.oy.image.service.impl.ImageManagerImpl" abstract="false"
lazy-init="default" autowire="default" dependency-check="default">
<property name="imageDao">
<ref bean="imageDao" />
</property>
</bean>

</beans>

2.MysqL

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-2.0.xsd">
<bean id="dataSource"
class="com.mchange.v2.c3p0.ComboPooledDataSource"
destroy-method="close">
<property name="driverClass">
<value>com.MysqL.jdbc.Driver</value>
</property>
<property name="jdbcUrl">
<value>
jdbc:MysqL://192.168.0.1:3306/DBName?useUnicode=true&amp;characterEncoding=UTF-8
</value>
</property>
<property name="user">
<value>root</value>
</property>
<property name="password">
<value>root</value>
</property>
<!-- 连接池中保留的最小连接数. -->
<property name="minPoolSize">
<value>5</value>
</property>
<!-- 连接池中保留的最大连接数。Default： 15 -->
<property name="maxPoolSize">
<value>30</value>
</property>
<!-- 初始化时获取的连接数，取值应在minPoolSize与maxPoolSize之间。Default： 3 -->
<property name="initialPoolSize">
<value>10</value>
</property>
<!-- 最大空闲时间，60秒内未使用则连接被丢弃。若为0则永不丢弃。Default： 0 -->
<property name="maxIdleTime">
<value>60</value>
</property>
<!-- 当连接池中的连接耗尽的时候c3p0一次同时获取的连接数。Default： 3 -->
<property name="acquireIncrement">
<value>5</value>
</property>

<!-- JDBC的标准参数，用以控制数据源内加载的PreparedStatements数量。但由于预缓存的statements
　　属于单个connection而不是整个连接池。所以设置这个参数需要考虑到多方面的因素。
　　如果maxStatements与maxStatementsPerConnection均为0，则缓存被关闭。Default： 0 -->

<property name="maxStatements">

<value>0</value>

</property>
<!-- 每60秒检查所有连接池中的空闲连接。Default： 0 -->

<property name="idleConnectionTestPeriod">

<value>60</value>

</property>
<!-- 定义在从数据库获取新连接失败后重复尝试的次数。Default： 30 -->

<property name="acquireRetryAttempts">

<value>30</value>

</property>

<!-- 获取连接失败将会引起所有等待连接池来获取连接的线程抛出异常。但是数据源仍有效
　　保留，并在下次调用getConnection（）的时候继续尝试获取连接。如果设为true，那么在尝试
　　获取连接失败后该数据源将申明已断开并永久关闭。Default： false-->

<property name="breakAfterAcquireFailure">

<value>true</value>

</property>

<!-- 因性能消耗大请只在需要的时候使用它。如果设为true那么在每个connection提交的

　　时候都将校验其有效性。建议使用idleConnectionTestPeriod或automaticTestTable

　　等方法来提升连接测试的性能。Default： false -->

<property name="testConnectionOnCheckout">

<value>false</value>

</property>
</bean>

<!-- Hibernate SessionFactory -->
<bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionfactorybean">
<property name="dataSource">
<ref local="dataSource" />
</property>
<property name="mappingResources">
<list>
<value>com/oy/image/model/LoginUser.hbm.xml</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">
org.hibernate.dialect.MysqLDialect
</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.generate_statistics">true</prop>
<prop key="hibernate.connection.release_mode">
auto
</prop>
<prop key="hibernate.autoReconnect">true</prop>
</props>
</property>
</bean>

<bean id="imageDao" name="imageDao"
class="com.oy.image.dao.hibernate.ImageDaoHibernate" abstract="false"
lazy-init="default" autowire="default" dependency-check="default">
<property name="sessionFactory">
<ref bean="sessionFactory" />
</property>
</bean>
<bean id="imageManager" name="imageManager"
class="com.oy.image.service.impl.ImageManagerImpl" abstract="false"
lazy-init="default" autowire="default" dependency-check="default">
<property name="imageDao">
<ref bean="imageDao" />
</property>
</bean>
</beans>

3.oracle

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-2.0.xsd">
<bean id="dataSource"
class="com.mchange.v2.c3p0.ComboPooledDataSource"
destroy-method="close" abstract="false"
lazy-init="default" autowire="default" dependency-check="default">
<property name="driverClass">
<value>oracle.jdbc.driver.OracleDriver</value>
</property>
<property name="jdbcUrl">
<value>jdbc:oracle:thin:@192.168.0.1:1521:orcl</value>
</property>
<property name="user">
<value>username</value>
</property>
<property name="password">
<value>password</value>
</property>
<property name="minPoolSize">
<value>10</value>
</property>
<property name="maxPoolSize">
<value>20</value>
</property>
<property name="initialPoolSize">
<value>10</value>
</property>
</bean>

<bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionfactorybean">
<property name="dataSource">
<ref bean="dataSource"></ref>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">
org.hibernate.dialect.OracleDialect
</prop>
<prop key="hibernate.show_sql">
false
</prop>
<prop key="hibernate.generate_statistics">true</prop>
<prop key="hibernate.cache.use_query_cache">
true
</prop>
<prop key="hibernate.cache.use_second_level_cache">
true
</prop>
<prop key="hibernate.cache.provider_class">
net.sf.ehcache.hibernate.EhCacheProvider
</prop>
<prop key="hibernate.connection.provider_class">
org.hibernate.connection.C3P0ConnectionProvider
</prop>
<prop key="hibernate.query.substitutions">
true 1,false 0,yes 'Y',no 'N'
</prop>
<prop
key="hibernate.bytecode.use_reflection_optimizer">
true
</prop>
<prop key="hibernate.use_outer_join">true</prop>
<prop key="hibernate.prepare_sql">true</prop>
<prop key="hibernate.query.factory_class">
org.hibernate.hql.ast.ASTQueryTranslatorFactory
</prop>
</props>
</property>

<property name="mappingResources">
<list>
<value>xxx/xx/xx.hbm.xml</value>
<value>xxx/xx/xx.hbm.xml</value>
</list>
</property>
</bean>


<bean id="imageDao" name="imageDao"
class="com.oy.image.dao.hibernate.ImageDaoHibernate" abstract="false"
lazy-init="default" autowire="default" dependency-check="default">
<property name="sessionFactory">
<ref bean="sessionFactory" />
</property>
</bean>
<bean id="imageManager" name="imageManager"
class="com.oy.image.service.impl.ImageManagerImpl" abstract="false"
lazy-init="default" autowire="default" dependency-check="default">
<property name="imageDao">
<ref bean="imageDao" />
</property>
</bean>
</beans>

转自http://blog.163.com/samoyed_kk/blog/static/853760092008526120434/