一.mysql数据库引入

<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="driverClass" value="com.mysql.jdbc.Driver" />
<property name="jdbcUrl" value="jdbc:mysql://127.0.0.1:3306/seckill?useUnicode=true&characterEncoding=utf8" />
<property name="user" value="root" />
<property name="password" value="123456" />

<!--c3po连接池的私有属性 -->
<property name="maxPoolSize" value="30" /><!--数据库连接池最大的连接对象 -->
<property name="minPoolSize" value="10" /><!--数据库连接池最小的连接对象 -->
<property name="autoCommitOnClose" value="false" /><!--关闭连接后不自动commit -->
<property name="checkoutTimeout" value="10000" /><!--数据库连接池最大连接池的等待时间
默认0，无限等待 -->
<property name="acquireRetryAttempts" value="20" /><!--获取连接失败时尝试获取次数 -->
</bean>

mysql  jar文件依赖

<!--二：数据库相关依赖 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.35</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>com.mchange</groupId>
<artifactId>c3p0</artifactId>
<version>0.9.2.1</version>
</dependency>