Spring框架学习-AOP操作-JdbcTemplate(操作数据库-查询)-11

一、JdbcTemplate操作数据库-单条数据 1、调用 JdbcTemplate 方法实现查询表 记录数

  // 查询
    @Override
    public int selectCount() {
        // 1创建sql语句
        String sql = "select count(*) from t_user";
        int count = jdbcTemplate.queryForObject(sql, Integer.class);
        return count;
    }

测试

 // 查询
    @Test
    public void query() {
        ApplicationContext context =
                new ClassPathXmlApplicationContext("bean1.xml");
        UserService userService = context.getBean("userService", UserService.class);
        int count = userService.findCount();
        System.out.println("表记录数"+count);
    }

2、调用 JdbcTemplate 方法实现查询返回对象

UserDaoImpl.java

  @Override
    public User findUserInfo(String id) {
        // 1创建sql语句
        String sql = "select * from t_user where userid=?";
        User user = jdbcTemplate.queryForObject(sql, new BeanPropertyRowMapper(User.class),id);
        return user;
    }

// 查询
    @Test
    public void findOne() {
        ApplicationContext context =
                new ClassPathXmlApplicationContext("bean1.xml");
        UserService userService = context.getBean("userService", UserService.class);
       User user = userService.findOne("1");
        System.out.println(user);
    }

3、调用 JdbcTemplate 方法实现查询返回集合

  // 查询返回集合
    @Override
    public List finAllUser() {
        // 1创建sql语句
        String sql = "select * from t_user";
        List userList = jdbcTemplate.query(sql, new BeanPropertyRowMapper(User.class));
        return userList;
    }

  // 查询返回集合
    @Test
    public void findAll() {
        ApplicationContext context =
                new ClassPathXmlApplicationContext("bean1.xml");
        UserService userService = context.getBean("userService", UserService.class);
        List userList= userService.findAll();
        System.out.println(userList);
    }

二、JdbcTemplate 操作数据库（批量操作） 1、JdbcTemplate 实现批量添加操作

//批量添加
@Override
public void batchAddBook(List batchArgs) {
 String sql = "insert into t_book values(?,?,?)";
 int[] ints = jdbcTemplate.batchUpdate(sql, batchArgs);
 System.out.println(Arrays.toString(ints));
}
//批量添加测试
List batchArgs = new ArrayList<>();
Object[] o1 = {"3","java","a"};
Object[] o2 = {"4","c++","b"};
Object[] o3 = {"5","MySQL","c"};
batchArgs.add(o1);
batchArgs.add(o2);
batchArgs.add(o3);
//调用批量添加
bookService.batchAdd(batchArgs);

2、JdbcTemplate 实现批量修改操作

//批量修改
  @Override
    public void batchUpdate(List batchArgs) {
        // 1创建sql语句
        String sql = "update t_user set username=?,ustatus=? where userid=?";
        int[] ints = jdbcTemplate.batchUpdate(sql, batchArgs);
        System.out.println(Arrays.toString(ints));
    }

  // 批量修改
    @Test
    public void updates() {
        ApplicationContext context =
                new ClassPathXmlApplicationContext("bean1.xml");
        UserService userService = context.getBean("userService", UserService.class);
        List batchArgs = new ArrayList<>();
        Object[] o1 ={"java_update","a","4"};
        Object[] o2 ={"C++_update","b","5"};
        Object[] o3 ={"mysql_update","c","6"};
        batchArgs.add(o1);
        batchArgs.add(o2);
        batchArgs.add(o3);
        // 调用批量添加
        userService.batchUpdate(batchArgs);
    }

3、JdbcTemplate 实现批量删除操作

    // 批量删除
    @Override
    public void batchDelete(List batchArgs) {
        // 1创建sql语句
        String sql = "delete from t_user where userid=?";

        int[] ints = jdbcTemplate.batchUpdate(sql, batchArgs);

        System.out.println(ints);
    }

    // 批量删除
    @Test
    public void deletes() {
        ApplicationContext context =
                new ClassPathXmlApplicationContext("bean1.xml");
        UserService userService = context.getBean("userService", UserService.class);
        List batchArgs = new ArrayList<>();

        Object[] o1 ={"4"};
        Object[] o2 ={"5"};

        batchArgs.add(o1);
        batchArgs.add(o2);

        userService.batchDelete(batchArgs);
    }