spring运用DBCP连接数据源

<bean id="dataSource" destroy-method="close"
class="org.apache.commons.dbcp.BasicDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql:///spring"/>
<property name="username" value="root"/>
<property name="password" value="root"/>
</bean>

package com.mxf.dao;

import java.sql.Connection;
import java.sql.SQLException;

import javax.annotation.Resource;
import javax.sql.DataSource;

import org.springframework.stereotype.Component;

@Component("userDAO")
public class UserDAO {
private DataSource dataSource;
public DataSource getDataSource() {
return dataSource;
}
@Resource(name="dataSource")
public void setDataSource(DataSource dataSource) {
this.dataSource = dataSource;
}
public void save() throws SQLException{
Connection con = dataSource.getConnection();
con.createStatement().executeUpdate("insert into user(id,name) values(null,'zhangsan')");
con.close();
System.out.println("user saved!");
}
}

<bean
class="org.springframework.beans.factory.config.PreferencesPlaceholderConfigurer">
<property name="locations">
<value>classpath:jdbc.properties</value>
</property>
</bean>
<bean id="dataSource" destroy-method="close"
class="org.apache.commons.dbcp.BasicDataSource">
<property name="driverClassName" value="${jdbc.driverClassName}" />
<property name="url" value="${jdbc.url}" />
<property name="username" value="${jdbc.username}" />
<property name="password" value="${jdbc.password}" />
</bean>