Mybatis入门（个人学习过程）

最新推荐文章于 2024-02-24 08:00:00 发布

HENG_YUAN

最新推荐文章于 2024-02-24 08:00:00 发布

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分类专栏：学习笔记文章标签： mybatis java

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Mybatis入门

一、我的第一个mybatis程序

1、搭建环境

在这里插入图片描述

使用Idea配置maven工程

编写pom.xml文件
引入mysql驱动包，junit包，还有mybatis包

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>study</groupId>
    <artifactId>mybatis</artifactId>
    <packaging>pom</packaging>
    <version>1.0-SNAPSHOT</version>
    <modules>
        <module>mybatis-day01</module>
        <module>mybatis-day02</module>
        <module>mybtis-day03</module>
    </modules>
    <dependencies>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.47</version>
    </dependency>
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.5.2</version>
    </dependency>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.11</version>
    </dependency>

</dependencies>
!--maven导出资源依赖-->
    <build>
        <resources>
        <resource>
            <directory>src/main/resources</directory>
            <includes>
                <include>**/*.properties</include>
                <include>**/*.xml</include>
            </includes>
            <filtering>true</filtering>
        </resource>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>true</filtering>
            </resource>
        </resources>

    </build>
</project>

2、编写数据库

2.1、编写数据库

CREATE DATABASE `mybatis`;

USE mybatis;


CREATE TABLE `user`(
`id` INT(20) NOT NULL PRIMARY KEY,
`name` VARCHAR(30) DEFAULT NULL,
`pwd` VARCHAR(30) DEFAULT NULL
)ENGINE =INNODB DEFAULT CHARSET=utf8;

INSERT INTO `user`(`id`,`name`,`pwd`) VALUES
(1,'呐喊','123456'),
(2,'咆哮','123456'),
(3,'狂喊','123456')

2.2、IDEA连接数据库

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2.3、在resource下新建一个xml文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <typeAliases>
        <package name="com.heng.pojo"/>
    </typeAliases>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF-8"/>
                <property name="username" value="root"/>
                <property name="password" value="123"/>
            </dataSource>
        </environment>
        <environment id="test">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
            <property name="driver" value="com.mysql.jdbc.Driver"/>
            <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF-8"/>
            <property name="username" value="root"/>
            <property name="password" value="123"/>
            </dataSource>
        </environment>
    </environments>
<!--mapper注册-->
    <mappers>
        <mapper resource="com/heng/dao/UserMapper.xml"></mapper>
    </mappers>
</configuration>

3、编写代码

包分类如下

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User类

package com.heng.pojo;


public class User {
    private int id;
    private String name;
    private String pwd;

    public User() {
    }

    public User(int id, String name, String pwd) {
        this.id = id;
        this.name = name;
        this.pwd = pwd;
    }

    public int getId() {
        return this.id;
    }

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

    public String getName() {
        return this.name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPwd() {
        return this.pwd;
    }

    public void setPwd(String pwd) {
        this.pwd = pwd;
    }

    public String toString() {
        return "User{id=" + this.id + ", name='" + this.name + '\'' + ", pwd='" + this.pwd + '\'' + '}';
    }

}

UserDao接口

package com.heng.dao;

import com.heng.pojo.User;

import java.util.List;

public interface UserDao {
//    查询所有数
    List<User> getUserList();
//    根据id查找
    User getUserId(int id);
//    增加用户
    int addUser(User user);
//    更新信息
    int upDate(User user);
//    删除
    int delete(int id);
}

UserDaoImpl

package com.heng.dao;

import com.heng.pojo.User;

import java.util.List;

public class UserDaoImpl implements UserDao {
    public List<User> getUserList() {
        return null;
    }

    @Override
    public User getUserId(int id) {
        return null;
    }

    @Override
    public int addUser(User user) {
        return 0;
    }

    @Override
    public int upDate(User user) {
        return 0;
    }

    @Override
    public int delete(int id ) {
        return 0;
    }
}

Mybatis

package com.heng.util;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import java.io.IOException;
import java.io.InputStream;

public class Mybatis {
 public static SqlSessionFactory sqlSessionFactory;

    static {
        try {
            String resource = "Mybatis-config.xml";
            InputStream inputStream = Resources.getResourceAsStream(resource);
            sqlSessionFactory = (new SqlSessionFactoryBuilder()).build(inputStream);
        } catch (IOException var3) {
            var3.printStackTrace();
        }

    }
    public static SqlSession getSqlSession(){
        return sqlSessionFactory.openSession();
    }
}

在dao包下面新建一个xml文件夹用来编写sql语句

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<!-- 命名空间-->
<mapper namespace="com.heng.dao.UserDao">
<!-- 查找用户-->
    <select id="getUserList" resultType="user">
          select * from mybatis.user
  </select>
    <!-- 根据id查询-->
    <select id="getUserId" resultType="user" parameterType="int">
        select * from mybatis.user where id =#{id}
         </select>
    <insert id="addUser" parameterType="com.heng.pojo.User">
        insert into mybatis.user(id, name, pwd) value (#{id},#{name},#{pwd})

    </insert>
    <update id="upDate" parameterType="com.heng.pojo.User">
        update mybatis.user set name=#{name},pwd=#{pwd} where id =#{id} ;
    </update>
    <delete id="delete" parameterType="com.heng.pojo.User">
        delete from mybatis.user where id=#{id}

    </delete>
</mapper>

4、编写测试类

//
// Source code recreated from a .class file by IntelliJ IDEA
// (powered by Fernflower decompiler)
//

package com.heng.dao;

import com.heng.pojo.User;
import com.heng.util.Mybatis;
import java.util.Iterator;
import java.util.List;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;

public class UserDaoTest {
    public UserDaoTest() {
    }

    @Test
    public void test() {
        SqlSession sqlSession = Mybatis.getSqlSession();
        UserDao userDao = (UserDao)sqlSession.getMapper(UserDao.class);
        List<User> userList = userDao.getUserList();
        Iterator var4 = userList.iterator();

        while(var4.hasNext()) {
            User user = (User)var4.next();
            System.out.println(user);
        }

        sqlSession.close();
    }

    @Test
    public void getUserId() {
        SqlSession sqlSession = Mybatis.getSqlSession();
        UserDao mapper = (UserDao)sqlSession.getMapper(UserDao.class);
        User user = mapper.getUserId(2);
        System.out.println(user);
        sqlSession.close();
    }

    @Test
    public void addUser() {
        SqlSession sqlSession = Mybatis.getSqlSession();
        UserDao mapper = (UserDao)sqlSession.getMapper(UserDao.class);
        int num = mapper.addUser(new User(4, "纸巾", "123465"));
        if (num > 0) {
            System.out.println("插入成功");
        }

        sqlSession.commit();
        sqlSession.close();
    }

    @Test
    public void upDate() {
        SqlSession sqlSession = Mybatis.getSqlSession();
        UserDao mapper = (UserDao)sqlSession.getMapper(UserDao.class);
        mapper.upDate(new User(2, "冰淇淋", "123456"));
        sqlSession.commit();
        sqlSession.close();
    }

    @Test
    public void delete() {
        SqlSession sqlSession = Mybatis.getSqlSession();
        UserDao mapper = (UserDao)sqlSession.getMapper(UserDao.class);
        mapper.delete(3);
        sqlSession.commit();
        sqlSession.close();
    }
}

二、resultMap

1、字段名与属性名不一致时，通过结果集来返回结果

<resultMap id="UserMap" type="User">
    <!--column是列名 peoperty是属性名-->
    <result column="id" property="id"/>
    <result column="name" property="name"/>
    <result column="pwd" property="password"/>

</resultMap>
<select id="getUserId" resultMap="UserMap">
    select * from mybatis.user where id =#{id}
     </select>

package com.heng.pojo;


public class User {
    private int id;
    private String name;
    private String password;

    public User() {
    }

    public User(int id, String name, String password) {
        this.id = id;
        this.name = name;
        this.password = password;
    }

    public int getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", password='" + password + '\'' +
                '}';
    }
}

1.1编写测试类，进行测试

@Test
public void getUserId(){
    SqlSession sqlSession = Mybatis.getSqlSession();
    UserDao mapper = sqlSession.getMapper(UserDao.class);
    User user = mapper.getUserId(2);
    System.out.println(user);
    sqlSession.close();
}

三、多对一的处理

1、新建student表和teacher表插入数据

CREATE TABLE `teacher`(
 `id` INT(20) NOT NULL,
 `name` VARCHAR(30) DEFAULT NULL,
 PRIMARY KEY(`id`)
 )ENGINE =INNODB DEFAULT CHARSET=utf8;

 

 CREATE TABLE `student`(
 `id` INT(20) NOT NULL,
 `name` VARCHAR(30) DEFAULT NULL,
 `tid` INT(20) DEFAULT NULL,
 PRIMARY KEY(`id`),
 KEY `fktid` (`tid`),
 CONSTRAINT `fktid` FOREIGN KEY (`tid`) REFERENCES `teacher` (`id`)
 )ENGINE =INNODB DEFAULT CHARSET=utf8;


 INSERT INTO `teacher`(`id`,`name`) VALUES('1','秦老师');

 INSERT INTO `student`(`id`,`name`,`tid`) VALUES('1','小明','1');
 INSERT INTO `student`(`id`,`name`,`tid`) VALUES('2','小红','1');
 INSERT INTO `student`(`id`,`name`,`tid`) VALUES('3','小李','1');
 INSERT INTO `student`(`id`,`name`,`tid`) VALUES('4','小王','1');
 INSERT INTO `student`(`id`,`name`,`tid`) VALUES('5','小秦','1');

2、编写代码

Student

package com.heng.pojo;

public class Student {
    private int id;
    private String name;
    private Teacher teacher;

    public Student() {
    }

    public Student(int id, String name, Teacher teacher) {
        this.id = id;
        this.name = name;
        this.teacher = teacher;
    }

    public int getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Teacher getTeacher() {
        return teacher;
    }

    public void setTeacher(Teacher teacher) {
        this.teacher = teacher;
    }

    @Override
    public String toString() {
        return "Student{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", teacher=" + teacher +
                '}';
    }
}

Teacher

package com.heng.pojo;

public class Teacher {
    private int id;
    private String name;

    public Teacher() {
    }

    public Teacher(int id, String name) {
        this.id = id;
        this.name = name;
    }

    public int getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return "TeacherMapper{" +
                "id=" + id +
                ", name='" + name + '\'' +
                '}';
    }
}


package com.heng.dao;

import java.util.List;

import com.heng.pojo.*;
public interface StudentMapper {
    public List<Student> getStudent();
}

UserMapper

package com.heng.dao;

import java.util.List;

import com.heng.pojo.*;
public interface StudentMapper {
    public List<Student> getStudent();
}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <properties resource="dp.properties"></properties>
    <settings>
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>
    <typeAliases>
        <package name="com.heng.pojo"/>
    </typeAliases>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="${driver}"/>
                <property name="url" value="${url}"/>
                <property name="username" value="${username}"/>
                <property name="password" value="${password}"/>
            </dataSource>
        </environment>
        <environment id="test">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="${driver}"/>
                <property name="url" value="${url}"/>
                <property name="username" value="${username}"/>
                <property name="password" value="${password}"/>
            </dataSource>
        </environment>
    </environments>
<mappers>
<!--    <mapper class="com/heng/dao/StudentMapper.xml"/>-->
    <mapper class="com.heng.dao.StudentMapper"/>
    <mapper class="com.heng.dao.TeacherMapper"/>
</mappers>
</configuratio

mybatis-mapper.xml

主要就是对前面的StudentMapper.xml和TeacherMapper.xml进行应用

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <properties resource="dp.properties"></properties>
    <settings>
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>
    <typeAliases>
        <package name="com.heng.pojo"/>
    </typeAliases>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="${driver}"/>
                <property name="url" value="${url}"/>
                <property name="username" value="${username}"/>
                <property name="password" value="${password}"/>
            </dataSource>
        </environment>
        <environment id="test">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="${driver}"/>
                <property name="url" value="${url}"/>
                <property name="username" value="${username}"/>
                <property name="password" value="${password}"/>
            </dataSource>
        </environment>
    </environments>
<mappers>
<!--    <mapper class="com/heng/dao/StudentMapper.xml"/>-->
    <mapper class="com.heng.dao.StudentMapper"/>
    <mapper class="com.heng.dao.TeacherMapper"/>
</mappers>
</configuratio

编写StudentMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.heng.dao.StudentMapper">
<!--    <select id="getStudent" resultType="Student">-->
<!--        select * from student-->
<!--    </select>-->
    <select id="getStudent" resultMap="StudentTeacher">
       select s.id sid,s.name sname,t.name tname
        from student s ,teacher t
        where s.tid=t.id;
    </select>
    <resultMap id="StudentTeacher" type="Student">
        <result property="id" column="sid"/>
        <result property="name" column="sname"/>
        <association property="teacher" javaType="Teacher">
            <result property="name" column="tname"/>
        </association>

    </resultMap>
</mapper>

编写测试类

    @Test
    public void getStudent() {
        SqlSession sqlSession = Mybatis.getSqlSession();
        StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
        List<Student> studentList= mapper.getStudent();
        for (Student student : studentList) {
            System.out.println(student);
        }
        sqlSession.close();

    }
}

四、一对多的处理

TeacherMapper.xml编写

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.heng.dao.TeacherMapper">
   <select id="getTeacher" resultMap="StudentTeacher">
     select s.id sid,s.name sname,t.name tname,t.id,tid
     from student s,teacher t
     where s.tid =t.id and t.id=#{tid}
   </select>
  <resultMap id="StudentTeacher" type="Teacher">
      <result property="id" column="tid" />
      <result property="name" column="tname" />
<!--      复杂的属性，我们需要单独处理 集合:collection  对象：associstion
   javaType="" 指定属性的类型
   OfTyp=""集合中的范型
-->
      <collection property="student" ofType="student">
          <result property="id" column="tid"/>
          <result property="name" column="tname" />
          <result property="tid" column="tid" />
      </collection>
  </resultMap>
</mapper>

测试类

@Test
public void getTeacher(){
    SqlSession sqlSession = Mybatis.getSqlSession();
    TeacherMapper mapper = sqlSession.getMapper(TeacherMapper.class);
    Teacher teacher = mapper.getTeacher(1);
    System.out.println(teacher);
    sqlSession.close();

}

package com.heng.dao;

import com.heng.pojo.Teacher;
import org.apache.ibatis.annotations.Param;

import java.util.List;

public interface TeacherMapper {
    //获取老师
    //List<Teacher> getTeacher();
    //获取学生指定的老师
    Teacher getTeacher(@Param("tid") int id);
}

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五、动态SQL环境搭建

1、什么是动态SQL？动态SQL就是根据不同的条件生成不同的SQL语句

2、搭建环境

2.1、新建表

create table `blog`(
`id` varchar(50) not null comment '博客id',
    `title` varchar(100) not null comment '博客标题',
    `author` varchar(30) not null comment `创建时间`,
    `create_time` datetime not null comment `创建时间`
    `views` int(30) not null comment('浏览量')
)engine=InnoDB default charset=utf-8;

2.2、编写xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.heng.dao.BlogMapper">
    <insert id="addUser" parameterType="blog">
        insert into mybatis.blog(id, title, author, create_time, views) values (#{id},#{title},#{author},#{createtime},#{views})
    </insert>
</mapper>

2.3、插入数据

import com.heng.dao.BlogMapper;
import com.heng.pojo.Blog;
import com.heng.util.IDutils;
import com.heng.util.Mybatis;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;

import java.util.Date;


public class MyTest {
    @Test
    public void getUser(){
        SqlSession sqlSession = Mybatis.getSqlSession();
        BlogMapper mapper = sqlSession.getMapper(BlogMapper.class);
        Blog blog = new Blog();
        blog.setId(IDutils.getID());
        blog.setTitle("java如此简单");
        blog.setAuthor("呐喊");
        blog.setCreatetime(new Date());
        blog.setViews(9999);
        mapper.addUser(blog);

        blog.setId(IDutils.getID());
        blog.setTitle("SpringBoot");
        blog.setAuthor("呐喊");
        mapper.addUser(blog);


        blog.setId(IDutils.getID());
        blog.setTitle("SpringMvc");
        blog.setAuthor("呐喊");
        mapper.addUser(blog);

        blog.setId(IDutils.getID());
        blog.setTitle("Spring");
        blog.setAuthor("呐喊");
        mapper.addUser(blog);

        sqlSession.commit();
        sqlSession.close();

    }
}

2.4、关于id的问题，在工具类新建一个类

这样就可自动生成id

package com.heng.util;

import org.junit.Test;

import java.util.UUID;

public class IDutils {
    public static String getID(){
        return UUID.randomUUID().toString();
    }

}

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3、动态sql之IF标签

xml文件编写sql语句

<!--    和java里面的if判断差不多-->
<!--    where 1=1 是将所有的数据都查出来-->
    <select id="queryBlog" parameterType="map" resultType="blog">
        select  * from mybatis.blog where 1= 1
        <if test="title != null">
            and title=#{title}
        </if>
        <if test="author != null">
            and author=#{author}
        </if>
    </select>

测试类

@Test
public void getBlog(){
    SqlSession sqlSession = Mybatis.getSqlSession();
    BlogMapper mapper = sqlSession.getMapper(BlogMapper.class);
    HashMap map = new HashMap();
    map.put("title","java如此简单");
    map.put("author","呐喊");
    List<Blog> blogs = mapper.queryBlog(map);

    for (Blog blog : blogs) {
        System.out.println(blog);
    }


}

4、where

where标签的好处就是，当你查询一个的时候，and会自动取消。

<select id="arrayBlog" parameterType="map" resultType="blog">
    select * from blog
    <where>
        <if test="title != null">
            title =#{title}
        </if>
        <if test="author != null">
            and author =#{author}
        </if>
    </where>

</select>

测试类

@Test
public  void getABlog() {
    SqlSession sqlSession = Mybatis.getSqlSession();
    BlogMapper mapper = sqlSession.getMapper(BlogMapper.class);
    HashMap map = new HashMap();
    map.put("title", "java如此简单");
    map.put("author", "呐喊");
    List<Blog> blo = mapper.arrayBlog(map);

    for (Blog blog : blo) {
        System.out.println(blog);
    }

}

5、choose when otherwise

在这个标签里面就是和java里面的swicht case循环一样，当首先匹配到一个就会优先筛选。

xml

<select id="listBlog" parameterType="map" resultType="blog">
    select * from mybatis.blog
    <where>
    <choose>
        <when test="title != null">
            and title=#{title}
        </when>
        <when test="author != null">
             and author = #{author}
        </when>
         <otherwise>
            and views = #{views}
         </otherwise>
    </choose>
    </where>
</select>

测试类

@Test
public  void getlisBlog(){
    SqlSession sqlSession = Mybatis.getSqlSession();
    BlogMapper mapper = sqlSession.getMapper(BlogMapper.class);
    HashMap map = new HashMap();
    //map.put("title","java如此简单");
    map.put("author","呐喊");
    map.put("views",9999);
    List<Blog> blogs = mapper.listBlog(map);
    for (Blog blog : blogs) {
        System.out.println(blog);

    }
    sqlSession.close();
}

6、trim、where、set

<update id="updateBlog" parameterType="map">
    update mybatis.blog
    <set>
        <if test="title != null">
            title=#{title},
        </if>
        <if test="author!=null">
            author=#{author}
        </if>
    </set>
    where id = #{id}
</updat

@Test
public void updateBlog(){
    SqlSession sqlSession = Mybatis.getSqlSession();
    BlogMapper mapper = sqlSession.getMapper(BlogMapper.class);
    HashMap map = new HashMap();
    map.put("title","Java");
    map.put("author","呐喊");
    map.put("id","ce860ea9-6d54-4778-acc3-4bd2dcacdf50");
    System.out.println( mapper.updateBlog(map));
    sqlSession.commit();
    sqlSession.close();
}