MyBatis的CRUD中的不同参数绑定查询

com.by.pojo下的User类

package com.by.pojo;

import java.io.Serializable;
import java.util.Date;

public class User implements Serializable {
    private Integer id;
    private String username;
    private Date birthday;
    private String sex;
    private String address;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public Date getBirthday() {
        return birthday;
    }

    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", username='" + username + '\'' +
                ", birthday=" + birthday +
                ", sex='" + sex + '\'' +
                ", address='" + address + '\'' +
                '}';
    }
}

测试类

private SqlSession sqlSession;
    private InputStream inputStream;

    @Before
    public void init() throws IOException {
        //加载配置文件
        String resource = "mybatis-config.xml";
        inputStream = Resources.getResourceAsStream(resource);

        //创建SessionFactory
        SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(inputStream);

        //使用数据的会话实例
        sqlSession = sessionFactory.openSession();
    }
​
@After
    public void close() throws IOException {
        sqlSession.close();
        inputStream.close();
    }

​

单个参数传递绑定

在UserDao接口中：

User getUserById(Integer id);

在UserDao.xml中：

<!--    传递单个参数-->
    <select id="getUserById" parameterType="java.lang.Integer" resultType="com.by.pojo.User">
        select * from user where id=#{id};
    </select>

测试类：

@Test
    //传递单个参数有
    public void testgetUserById() throws IOException {
        //返回接口的代理类
        UserDao userDao = sqlSession.getMapper(UserDao.class);
        User user = userDao.getUserById(43);
        System.out.println(user);
    }

序号参数传递绑定

在UserDao接口中：

//序号多个参数
    User getUser(Integer id, String username);

在UserDao.xml中：

<!--    序号传递多个参数-->
    <select id="getUser" resultType="com.by.pojo.User">
    select * from user where id=#{arg0} and username=#{arg1};
    select * from user where id=#{param1} and username=#{param2};
    </select>

测试类：

@Test
    //序号传递多个参数
    public void testgetUser() throws IOException {
        //返回接口的代理类
        UserDao userDao = sqlSession.getMapper(UserDao.class);
        User user = userDao.getUser(43, "俞莲舟");
        System.out.println(user);
    }

注解参数传递绑定

在UserDao接口中：

//注解多个参数
    User getUser2(@Param("id") Integer id, @Param("username") String username);

在UserDao.xml中：

<!--    注解传递多个参数-->
    <select id="getUser2"  resultType="com.by.pojo.User">
        select * from user where id=#{id} and username=#{username};
    </select>

测试类：

@Test
    //注解传递多个参数
    public void testgetUser2() throws IOException {

        //返回接口的代理类
        UserDao userDao = sqlSession.getMapper(UserDao.class);
        User user = userDao.getUser2(43, "俞莲舟");
        System.out.println(user);
    }

pojo（对象）参数传递绑定

在UserDao接口中：

//pojo参数
    User getUser3(User user);

在UserDao.xml中：

<!--    pojo传递多个参数-->
    <select id="getUser3" parameterType="com.by.pojo.User" resultType="com.by.pojo.User">
        select * from user where id=#{id} and username=#{username};
    </select>

测试类：

@Test
    //pojo(对象)传递多个参数
    public void testgetUser3() throws IOException {
        //返回接口的代理类
        UserDao userDao = sqlSession.getMapper(UserDao.class);
        User userParam = new User();
        userParam.setId(43);
        userParam.setUsername("俞莲舟");
        User user = userDao.getUser3(userParam);
        System.out.println(user);
    }

map参数传递绑定

在UserDao接口中：

//map参数
    User getUser4(Map<String, Object> map);

在UserDao.xml中：

</select>
    <!--    map传递多个参数-->
    <select id="getUser4" parameterType="java.util.Map" resultType="com.by.pojo.User">
        select * from user where id=#{id} and username=#{username};
    </select>

测试类：

@Test
    //map传递多个参数
    public void testgetUser4() throws IOException {
        //返回接口的代理类
        UserDao userDao = sqlSession.getMapper(UserDao.class);
        HashMap<String, Object> map = new HashMap<>();
        map.put("id", 43);
        map.put("username", "俞莲舟");
        User user = userDao.getUser4(map);
        System.out.println(user);
    }