JdbcTemplate

环境搭建

spring 提供用于操作JDBC工具类，类似：DBUtils。
依赖 连接池DataSource （数据源）

导入jar包

javabean

public class User {
	private Integer id;
	private String username;
	private String password;
}

dao层

public class UserDao {
    JdbcTemplate jdbcTemplate;

    public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
        this.jdbcTemplate = jdbcTemplate;
    }

    public List> SelectAll(){
        List> maps = jdbcTemplate.queryForList("select * from user ");
        return maps;
    }
}

JdbcTemplate的替代品UserDao  extends JdbcDaoSupport 不用每次都生成jdbcTemplate对象
public class UserDao extends JdbcDaoSupport {
//    JdbcTemplate jdbcTemplate;
//
//    public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
//        this.jdbcTemplate = jdbcTemplate;
//    }

    public List> SelectAll(){
        List> maps = this.getJdbcTemplate().queryForList("select * from user ");
        return maps;
    }
}

两种连接池 spring配置

DBCP

JdbcDaoSupport的写法


		

C3P0

Test

  public void demo01(){
        //创建dao
        String xmlPath="jdbc/a_domain/c_dbcp/beans.xml";
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext(xmlPath);
        UserDao userDao = (UserDao) applicationContext.getBean("UserDaoId");
        List> maps = userDao.SelectAll();
        for (Map map : maps) {
            System.out.println(map);
        }
    }