Mybatis3

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原创最新推荐文章于 2026-09-21 12:27:05 发布 444 阅读 AI 写同款· GEO 优化 ›

Mybatis详解系列(五)–Mybatis Generator和全注解风格的MyBatis3DynamicSql 简介 Mybatis Generator (MBG) 是 Mybatis 官方提供的代码生成器，通过它可以在项目中自动生成简单的 CRUD 方法，甚至“无所不能”的高级条件查询(MyBatis3DynamicSql，有了它根本不需要 Mybatis Plus)，让我们避免了进行数据库交互时需要手动创建对象和配置 Mybatis 映射等基础工作。另外，MBG 有很好地扩展性，它提供了大量... 阅读详情

MyBatis3

testcase for Mybatis:

数据库：

blog:

CREATE TABLE `blog` (
  `blogid` int(11) NOT NULL AUTO_INCREMENT,
  `blogtile` char(20) DEFAULT NULL,
  `authorid` int(11) NOT NULL,
  PRIMARY KEY (`blogid`),
  KEY `fk_authorid` (`authorid`),
  CONSTRAINT `fk_authorid` FOREIGN KEY (`authorid`) REFERENCES `author` (`authorid`)
) ENGINE=InnoDB AUTO_INCREMENT=6 DEFAULT CHARSET=utf8;

author:

CREATE TABLE `author` (
  `authorid` int(11) NOT NULL AUTO_INCREMENT,
  `name` char(20) DEFAULT NULL,
  `sex` char(1) DEFAULT NULL,
  PRIMARY KEY (`authorid`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8;

person:

CREATE TABLE `person` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `name` char(100) DEFAULT NULL,
  `age` int(3) DEFAULT NULL,
  `sex` char(1) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=19 DEFAULT CHARSET=utf8;

post:

CREATE TABLE `post` (
  `postid` int(11) NOT NULL AUTO_INCREMENT,
  `postcomment` char(20) DEFAULT NULL,
  `blogid` int(11) NOT NULL,
  PRIMARY KEY (`postid`),
  KEY `fk_blogid` (`blogid`),
  CONSTRAINT `fk_blogid` FOREIGN KEY (`blogid`) REFERENCES `blog` (`blogid`)
) ENGINE=InnoDB AUTO_INCREMENT=18 DEFAULT CHARSET=utf8;

mybatis-config.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "mybatis-3-config.dtd" >
<configuration>
	<!-- 关联属性文件，使用${}使用 -->
	<properties resource="db.properties"/>
	<!-- 定义类型别名 -->	
	<typeAliases>
		<!-- <typeAlias type="" alias=""/> -->
		<package name="main.bean"/>
	</typeAliases>
	<!-- 配置数据库环境信息 -->
	<environments default="mysql">
		<environment id="mysql">
			<!--指定事务管理类型[JDBC|MANAGED]  -->
			<transactionManager type="JDBC"></transactionManager>
			<!-- 配置JDBC连接对象的资源 POOLED:数据源连接池实现 -->
			<dataSource type="POOLED">
				<property name="driver" value="${driver}" />  
		        <property name="url" value="${url}" />  
		        <property name="username" value="${username}" />  
		        <property name="password" value="${password}" /> 			
			</dataSource>
		</environment>
	</environments>
	<mappers>
		<mapper resource="main/config/mapper/person-mapper.xml"/>
	</mappers>
</configuration>

author.java

package main.bean;

public class author {
	
	private int authorid;
	private String name;
	private String sex;
	
	public author() {
		super();
		// TODO Auto-generated constructor stub
	}

	public author(int authorid, String name, String sex) {
		super();
		this.authorid = authorid;
		this.name = name;
		this.sex = sex;
	}

	public int getAuthorid() {
		return authorid;
	}

	public void setAuthorid(int authorid) {
		this.authorid = authorid;
	}

	public String getName() {
		return name;
	}

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

	public String getSex() {
		return sex;
	}

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

	@Override
	public String toString() {
		return "author [authorid=" + authorid + ", name=" + name + ", sex=" + sex + "]";
	}
	
	
}

package main.bean;

import java.util.List;

public class blog {

		private int blogid;
		private String blogtile;
		private author aut;
		private List<post> posts;
		public blog() {
			super();
			// TODO Auto-generated constructor stub
		}
		public blog(int blogid, String blogtile, author aut, List<post> posts) {
			super();
			this.blogid = blogid;
			this.blogtile = blogtile;
			this.aut = aut;
			this.posts = posts;
		}
		public int getBlogid() {
			return blogid;
		}
		public void setBlogid(int blogid) {
			this.blogid = blogid;
		}
		public String getBlogtile() {
			return blogtile;
		}
		public void setBlogtile(String blogtile) {
			this.blogtile = blogtile;
		}
		public author getAut() {
			return aut;
		}
		public void setAut(author aut) {
			this.aut = aut;
		}
		public List<post> getPosts() {
			return posts;
		}
		public void setPosts(List<post> posts) {
			this.posts = posts;
		}
		@Override
		public String toString() {
			return "blog [blogid=" + blogid + ", blogtile=" + blogtile + ", aut=" + aut + ", posts=" + posts + "]";
		}
		
}

person.java

package main.bean;

public class person {
	
	private int id;
	private String name;
	private int age;
	private String sex;
	
	
	public person() {
		super();
		// TODO Auto-generated constructor stub
	}
	public person(int id, String name, int age, String sex) {
		super();
		this.id = id;
		this.name = name;
		this.age = age;
		this.sex = sex;
	}
	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 int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
	public String getSex() {
		return sex;
	}
	public void setSex(String sex) {
		this.sex = sex;
	}
	@Override
	public String toString() {
		return "person [id=" + id + ", name=" + name + ", age=" + age + ", sex=" + sex + "]";
	}
	
	
}

post.java

package main.bean;

public class post {
	
	private int postid;
	private String postcomment;
	private int blogid;
	public post() {
		super();
		// TODO Auto-generated constructor stub
	}
	public post(int postid, String postcomment, int blogid) {
		super();
		this.postid = postid;
		this.postcomment = postcomment;
		this.blogid = blogid;
	}
	public int getPostid() {
		return postid;
	}
	public void setPostid(int postid) {
		this.postid = postid;
	}
	public String getPostcomment() {
		return postcomment;
	}
	public void setPostcomment(String postcomment) {
		this.postcomment = postcomment;
	}
	public int getBlogid() {
		return blogid;
	}
	public void setBlogid(int blogid) {
		this.blogid = blogid;
	}
	@Override
	public String toString() {
		return "post [postid=" + postid + ", postcomment=" + postcomment + ", blogid=" + blogid + "]";
	}
	
}

person-mapper.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "mybatis-3-mapper.dtd" >
<mapper namespace="main.config.mapper.person-mapper">

<select id="selectPerson" parameterType="int" resultType="person">
	SELECT * FROM person WHERE id = ${_parameter}
</select>

<insert id="insertPerson" parameterType="person"> 
	INSERT INTO person(name, age, sex) VALUES(#{name}, #{age}, #{sex})
</insert>

<update id="updatePerson" parameterType="person">
	UPDATE person SET 
		name = #{name},
		age = #{age},
		sex = #{sex}
	WHERE id = #{id}
</update>
<delete id="deletePerson" parameterType="int">
	DELETE FROM person WHERE id = #{_parameter}
</delete>
<!-- 一对一关系 -->
<select id="selectBlog" parameterType="int" resultMap="blogResult">
	SELECT * FROM blog INNER JOIN author ON blog.authorid = author.authorid WHERE blog.blogid = #{_parameter}
</select>

<resultMap id="blogResult" type="blog">
	<id property="blogid" column="blogid"/>
	<result property="blogtile" column="blogtile"/>
	<association property="aut" column="authorid" javaType="author" resultMap="authorResult"></association>
</resultMap>
<!-- author表和author的映射关系 -->
<resultMap id="authorResult" type="author">
	<id property="authorid" column="authorid"/>
	<result property="name" column="name"/>
	<result property="sex" column="sex"/>
</resultMap>


<!-- 一对多关系 -->
<select id="selectBlogAndPosts" parameterType="int" resultMap="blogResult2">
	SELECT * FROM blog INNER JOIN post ON blog.blogid = post.blogid WHERE blog.blogid = #{_parameter}
</select>
<resultMap type="blog" id="blogResult2">
	<id property="blogid" column="blogid"/>
	<result property="blogtile" column="blogtile"/>
	<collection property="posts" ofType="post" resultMap="postResult"/>
</resultMap>

<resultMap type="post" id="postResult">
	<id property="postid" column="postid"/>
	<result property="postcomment" column="postcomment"/>
	<result property="blogid" column="blogid"/>
</resultMap>

<!-- 动态sql foreach -->
<select id="selectForeach" parameterType="list" resultMap="blogResult2">
	SELECT * FROM blog INNER JOIN post ON blog.blogid = post.blogid 
	WHERE blog.blogid IN 
	<foreach collection="list" index="index" item="item" open="(" separator="," close=")"> 
		#{item}
	</foreach>
</select>
</mapper>

Factory.java

package main.factory;

import java.io.IOException;
import java.io.Reader;

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

public class Factory {
	private static Factory factory;
	private static SqlSessionFactory sqlSessionFactory;
	private Factory(){
		try{
			String resource = "main/config/mybatis-config.xml"; 
			Reader reader = Resources.getResourceAsReader(resource); 
			sqlSessionFactory = (SqlSessionFactory) new SqlSessionFactoryBuilder().build(reader); 
		}catch(IOException e){
			System.out.println(e.getMessage());
		}catch(Exception e){
			System.out.println(e.getMessage());
		}
	}
	public static SqlSessionFactory getFactory(){
		if(factory == null){
			factory = new Factory();
			return factory.sqlSessionFactory;
		}else
			return factory.sqlSessionFactory;
	}
}

test.java

package main.test;

import java.util.ArrayList;
import java.util.List;

import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.junit.Test;

import main.bean.blog;
import main.bean.person;
import main.factory.Factory;

public class test {
	

	
	@Test
	public void testInsert(){
		SqlSessionFactory factory = Factory.getFactory();
		SqlSession session = null;
		person p1 = new person(2, "lisi", 12, "w");
		try{
			//session = factory.openSession(true);
			//默认是手动提交事务
			session = factory.openSession();
			int result = session.insert("main.config.mapper.person-mapper.insertPerson", p1);
			//需要手动提交
			session.commit();
			System.out.println(result);
		}catch(Exception e){
			System.out.println(e.toString());
		}finally{
			session.close();
		}
	}
	
	@Test
	public void testSelect(){
		SqlSessionFactory factory = Factory.getFactory();
		SqlSession session = null;
		try{
			session = factory.openSession();
			person p = session.selectOne("main.config.mapper.person-mapper.selectPerson", 2);
			System.out.println(p.toString());
		//虽然session的方法签名不需要catch异常
		}catch(Exception e){
			System.out.println(e.toString());
		}finally{
			session.close();
		}
	}
	
	@Test
	public void testUpdate(){
		SqlSessionFactory factory = Factory.getFactory();
		SqlSession session = null;
		person p1 = new person(11, "houshaoli", 25, "m");
		try{
			session = factory.openSession(true);
			int result = session.update("main.config.mapper.person-mapper.updatePerson", p1);
			System.out.println(result);
		}catch(Exception e){
			System.out.println(e.toString());
		}finally{
			session.close();
		}
	}
	
	@Test
	public void testDelete(){
		SqlSessionFactory factory = Factory.getFactory();
		SqlSession session = null;
		try{
			session = factory.openSession(true);
			int result = session.delete("main.config.mapper.person-mapper.deletePerson", 11);
			System.out.println(result);
		}catch(Exception e){
			System.out.println(e.toString());
		}finally{
			session.close();
		}
	}
	//一对一映射
	@Test
	public void testSelectOneToOne(){
		SqlSessionFactory factory = Factory.getFactory();
		SqlSession session = null;
		try{
			session = factory.openSession(true);
			blog b1 = session.selectOne("main.config.mapper.person-mapper.selectBlog", 1);
			System.out.println(b1.toString());
		}catch(Exception e){
			System.out.println(e.toString());
		}finally{
			session.close();
		}
	}
	
	//一对多集合
	@Test
	public void testSelectOneToMutil(){
		SqlSessionFactory factory = Factory.getFactory();
		SqlSession session = null;
		try{
			session = factory.openSession(true);
			blog b = session.selectOne("main.config.mapper.person-mapper.selectBlogAndPosts", 1);
			System.out.println(b.toString());
		}catch(Exception e){
			System.out.println(e.toString());
		}finally{
			session.close();
		}
	}
	
	//动态sql foreach实例
	@Test
	public void testSelectOneToMutil2(){
		SqlSessionFactory factory = Factory.getFactory();
		SqlSession session = null;
		try{
			session = factory.openSession(true);
			List<String> list = new ArrayList<String>();
			list.add("2");
			list.add("1");
			list.add("6");
			List<blog> blist = session.selectList("main.config.mapper.person-mapper.selectForeach", list);
			for(blog b: blist){
				System.out.println(b.toString());				
			}
		}catch(Exception e){
			System.out.println(e.toString());
		}finally{
			session.close();
		}
	}
}