标签:管理 多表 users void email get obj 数据库 pre
1.DBCP
a.定义:DBCP(DataBase Connection Pool)数据库连接池,是java数据库连接池的一种,由Apache开发,通过数据库连接池,可以让程序自动管理数据库连接的释放和断开
b.配置:
<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://localhost:3306/emp" /> <property name="username" value="root" /> <property name="password" value="admin"/> <property name="maxActive" value="10"></property> <property name="initialSize" value="2"></property> <property name="minIdle" value="2"></property> <property name="maxIdle" value="3"></property> </bean> <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate"> <property name="dataSource" ref="dataSource" /> </bean>
c.使用:
@Repository public class UserDao { @Resource private JdbcTemplate template; //增 public void addUser(String name,String pwd){ int userType=1; String sql="insert into users(user_name,user_pwd,user_type) values(?,?,?)"; jdbcTemplate.update(sql,new Object[]{name,pwd,userType}); } //删 public void delUserById(int id){ String sql="delete from users where user_id=?"; jdbcTemplate.update(sql,new Object[]{id}); } //改 public void updateUser(User user){ String sql="update users set user_name=?,user_pwd=?,user_type=? where user_id=?"; jdbcTemplate.update(sql,new Object[]{user.getUserName(),user.getUserPwd(),user.getUserType(),user.getUserId()}); } //查——方法一 public List<User> findAllUser(){ String sql="select * from users"; List<User> list=jdbcTemplate.query(sql,new BeanPropertyRowMapper(User.class)); return list; } //查——方法二 public List<User> getAllUser(){ String sql="select * from users"; List<User> list=jdbcTemplate.query(sql,new RowMapper(){ @Override public Object mapRow(ResultSet arg0, int arg1) throws SQLException { User u=new User(); if(arg0!=null){ u.setUserId(arg0.getInt("user_id")); u.setUserName(arg0.getString("user_name")); u.setUserPwd(arg0.getString("user_pwd")); u.setUserId(arg0.getInt("user_type")); } return u; } }); return list; } //多表联查 public List<User> getAllUserAndInfo(){ String sql="select u.user_name,u.user_type,i.info_nickName,i.info_email from users u left join userInfo i on u.user_id=i.user_id "; List<User> list=jdbcTemplate.query(sql,new RowMapper(){ @Override public Object mapRow(ResultSet arg0, int arg1) throws SQLException { User u=new User(); if(arg0!=null){ u.setUserName(arg0.getString("user_name")); u.setUserType(arg0.getInt("user_type")); UserInfo info=new UserInfo(); info.setInfoEmail(arg0.getString("info_email")); info.setInfoNickName(arg0.getString("info_nickName")); u.setInfo(info); } return u; } }); return list; } }
标签:管理 多表 users void email get obj 数据库 pre
原文地址:http://www.cnblogs.com/vettel0329/p/6561380.html