spring中的jdbcTemplate

Posted 2020-09-05

spring核心配置文件中的内容

<!-- 注入dataSource -->
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
        <property name="url" value="jdbc:mysql://localhost:3306/db_user"></property>
        <property name="username" value="root"></property>
        <property name="password" value="258764547"></property>
    </bean>
    <!-- 注入jdbcTemplate -->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <!-- 在jdbcTemplate中注入dataSource属性 -->
        <property name="dataSource" ref="dataSource"></property>
    </bean>
        <!-- 注入 userDaoImpl-->
    <bean id="userDaoImpl" class="com.yudo.dao.impl.UserDaoImpl">
        <!-- 在userDaoImpl中注入jdbcTemplate属性  -->
        <property name="jdbcTemplate" ref="jdbcTemplate"></property>
    </bean>

增，删，改的代码、

public class UserDaoImpl {
    private JdbcTemplate jdbcTemplate;

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

    public void add() {
        User user = new User();
        user.setUsername("关羽");
        user.setPassword("456");
        user.setAge(43);
        user.setAddress("荆州");
        String sql = "insert into t_user (username,password,age,address) values (?,?,?,?)";
        jdbcTemplate.update(sql, user.getUsername(), user.getPassword(),user.getAge(), user.getAddress());
    }

    public void delete() {
        String username = "张飞";
        String sql = "delete from t_user where username=?";
        jdbcTemplate.update(sql, username);
    }

    public void update() {
        String sql = "update t_user set age=?, address=? where username=?";
        jdbcTemplate.update(sql, "45", "蜀国", "关羽");
    }

查询功能：　　

　　<1.返回单一对象

//返回单一对象
    public void find1() {
        String sql = "select * from t_user where username=?";
        User user = jdbcTemplate.queryForObject(sql, new MapRow(), "关羽");
        System.out.println(user);
    }
    

new MapRow()的对象

class MapRow implements RowMapper<User> {
    @Override
    public User mapRow(ResultSet arg0, int arg1) throws SQLException {
        // TODO Auto-generated method stub
        String username = arg0.getString("username");
        String password = arg0.getString("password");
        Integer age = arg0.getInt("age");
        String address = arg0.getString("address");
        User user = new User();
        user.setUsername(username);
        user.setPassword(password);
        user.setAge(age);
        user.setAddress(address);
        return user;
    }
}

<2.返回List集合

//返回List集合
    public void find2(){
        String sql = "select * from t_user";
        List<User> list = jdbcTemplate.query(sql, new MapRow());
        for (User user : list) {
            System.out.println(user);
        }
    }

测试类：

@Test
    public void DemoTest() {
        ApplicationContext ctx = new ClassPathXmlApplicationContext(
                "applicationContext.xml");
        UserDaoImpl userDaoImpl = (UserDaoImpl) ctx.getBean("userDaoImpl");
//      userDaoImpl.add();
//      userDaoImpl.delete();
//      userDaoImpl.update();
//      userDaoImpl.find1();
        userDaoImpl.find2();
        
    }

 

对增，删，改，的批量操作时，用到方法batchUpdate(sql, batchArgs);

batchArgs为Object类的数组