javaEE Spring，JDBC，JdbcDaoSupport(根据DataSource连接池自动创建JdbcTemplate)

UserDaoImpl.java（Dao层实现类,继承JdbcDaoSupport）：

package cn.xxx.jdbctemplate;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
//import org.springframework.jdbc.core.JdbcTemplate;

import cn.xxx.bean.User;

//JdbcDaoSupport会根据连接池自动创建JdbcTemplate
//使用JdbcTemplate模板实现增删改查
public class UserDaoImpl extends JdbcDaoSupport implements UserDao {  //继承JdbcDaoSupport
	
	//private JdbcTemplate jt;  //直接使用父类JdbcDaoSupport中的JdbcTemplate
	
	@Override
	public void save(User u) {
		String sql = "insert into t_user values(null,?) ";
		//jt.update(sql, u.getName());
		super.getJdbcTemplate().update(sql, u.getName()); //直接使用父类JdbcDaoSupport中的JdbcTemplate
	}
	
	@Override
	public void delete(Integer id) {
		String sql = "delete from t_user where id = ? ";
		super.getJdbcTemplate().update(sql,id);
	}
	
	@Override
	public void update(User u) {
		String sql = "update  t_user set name = ? where id=? ";
		super.getJdbcTemplate().update(sql, u.getName(),u.getId());
	}
	
	@Override
	public User getById(Integer id) {
		String sql = "select * from t_user where id = ? ";
		return super.getJdbcTemplate().queryForObject(sql,new RowMapper<User>(){
			@Override
			public User mapRow(ResultSet rs, int index) throws SQLException {
				User u = new User();
				u.setId(rs.getInt("id"));
				u.setName(rs.getString("name"));
				return u;
			}}, id);   //RowMapper类似于QueryRunner的query方法中的xxxHandler
	}
	
	@Override
	public int getTotalCount() {
		String sql = "select count(*) from t_user  ";
		Integer count = super.getJdbcTemplate().queryForObject(sql, Integer.class);
		return count;
	}

	@Override
	public List<User> getAll() {
		String sql = "select * from t_user  ";
		List<User> list = super.getJdbcTemplate().query(sql, new RowMapper<User>(){
			@Override
			public User mapRow(ResultSet rs, int index) throws SQLException {
				User u = new User();
				u.setId(rs.getInt("id"));
				u.setName(rs.getString("name"));
				return u;
			}});
		return list;
	}

}

src/applicationContext.xml（Spring配置文件,将JdbcDaoSupport的子类配置到Spring容器中）：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd ">
	
	<!-- 1.将(c3p0)连接池放入spring容器 -->
	<bean name="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" >
		<property name="jdbcUrl" value="jdbc:mysql:///数据库名" ></property>
		<property name="driverClass" value="com.mysql.jdbc.Driver" ></property>
		<property name="user" value="root" ></property>
		<property name="password" value="1234" ></property>
	</bean>
	
	<!-- 2.将UserDao(JdbcDaoSupport的子类)放入spring容器 -->
	<bean name="userDao" class="cn.xxx.jdbctemplate.UserDaoImpl" >
		<!-- JdbcDaoSupport根据注入的dataSource自动创建JdbcTemplate;不需要再配置JdbcTemplate对象了 -->
		<property name="dataSource" ref="dataSource" ></property>
	</bean>

</beans>