Mybatis属于半自动ORM，在使用这个框架中，工作量最大的就是书写Mapping的映射文件，由于手动书写很容易出错，我们可以利用Mybatis-Generator来帮我们自动生成文件。
关于Mybatis-Generator的下载可以到这个地址：https://github.com/mybatis/generator/releases
由于我使用的是Mysql数据库，这里需要再准备一个连接mysql数据库的驱动jar包
以下是相关文件截图：
和Hibernate逆向生成一样，这里也需要一个配置文件：
generatorConfig.xml
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN" "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd"> <generatorConfiguration> <!--数据库驱动--> <classPathEntry location="mysql-connector-java-5.0.8-bin.jar"/> <context id="DB2Tables" targetRuntime="MyBatis3"> <commentGenerator> <property name="suppressDate" value="true"/> <property name="suppressAllComments" value="true"/> </commentGenerator> <!--数据库链接地址账号密码--> <jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://localhost/mymessages" userId="root" password="root"> </jdbcConnection> <javaTypeResolver> <property name="forceBigDecimals" value="false"/> </javaTypeResolver> <!--生成Model类存放位置--> <javaModelGenerator targetPackage="lcw.model" targetProject="src"> <property name="enableSubPackages" value="true"/> <property name="trimStrings" value="true"/> </javaModelGenerator> <!--生成映射文件存放位置--> <sqlMapGenerator targetPackage="lcw.mapping" targetProject="src"> <property name="enableSubPackages" value="true"/> </sqlMapGenerator> <!--生成Dao类存放位置--> <javaClientGenerator type="XMLMAPPER" targetPackage="lcw.dao" targetProject="src"> <property name="enableSubPackages" value="true"/> </javaClientGenerator> <!--生成对应表及类名--> <table tableName="message" domainObjectName="Messgae" enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false"></table> </context> </generatorConfiguration>
需要修改文件配置的地方我都已经把注释标注出来了，这里的相关路径（如数据库驱动包，生成对应的相关文件位置可以自定义）不能带有中文。
上面配置文件中的：
<table tableName="message" domainObjectName="Messgae" enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false"></table>
tableName和domainObjectName为必选项，分别代表数据库表名和生成的实体类名，其余的可以自定义去选择（一般情况下均为false）。
生成语句文件：
java -jar mybatis-generator-core-1.3.2.jar -configfile generatorConfig.xml -overwrite
2、使用方法
在该目录按住Shift键，右键鼠标选择"在此处打开命令窗口"，复制粘贴生成语句的文件代码即可。
看下效果图：
首先这个是我的数据库表
生成相关代码：
Message.java
package lcw.model; public class Messgae { private Integer id; private String title; private String describe; private String content; public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getTitle() { return title; } public void setTitle(String title) { this.title = title == null ? null : title.trim(); } public String getDescribe() { return describe; } public void setDescribe(String describe) { this.describe = describe == null ? null : describe.trim(); } public String getContent() { return content; } public void setContent(String content) { this.content = content == null ? null : content.trim(); } }
MessgaeMapper.xml
<?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" > <mapper namespace="lcw.dao.MessgaeMapper" > <resultMap id="BaseResultMap" type="lcw.model.Messgae" > <id column="id" property="id" jdbcType="INTEGER" /> <result column="title" property="title" jdbcType="VARCHAR" /> <result column="describe" property="describe" jdbcType="VARCHAR" /> <result column="content" property="content" jdbcType="VARCHAR" /> </resultMap> <sql id="Base_Column_List" > id, title, describe, content </sql> <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" > select <include refid="Base_Column_List" /> from message where id = #{id,jdbcType=INTEGER} </select> <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" > delete from message where id = #{id,jdbcType=INTEGER} </delete> <insert id="insert" parameterType="lcw.model.Messgae" > insert into message (id, title, describe, content) values (#{id,jdbcType=INTEGER}, #{title,jdbcType=VARCHAR}, #{describe,jdbcType=VARCHAR}, #{content,jdbcType=VARCHAR}) </insert> <insert id="insertSelective" parameterType="lcw.model.Messgae" > insert into message <trim prefix="(" suffix=")" suffixOverrides="," > <if test="id != null" > id, </if> <if test="title != null" > title, </if> <if test="describe != null" > describe, </if> <if test="content != null" > content, </if> </trim> <trim prefix="values (" suffix=")" suffixOverrides="," > <if test="id != null" > #{id,jdbcType=INTEGER}, </if> <if test="title != null" > #{title,jdbcType=VARCHAR}, </if> <if test="describe != null" > #{describe,jdbcType=VARCHAR}, </if> <if test="content != null" > #{content,jdbcType=VARCHAR}, </if> </trim> </insert> <update id="updateByPrimaryKeySelective" parameterType="lcw.model.Messgae" > update message <set > <if test="title != null" > title = #{title,jdbcType=VARCHAR}, </if> <if test="describe != null" > describe = #{describe,jdbcType=VARCHAR}, </if> <if test="content != null" > content = #{content,jdbcType=VARCHAR}, </if> </set> where id = #{id,jdbcType=INTEGER} </update> <update id="updateByPrimaryKey" parameterType="lcw.model.Messgae" > update message set title = #{title,jdbcType=VARCHAR}, describe = #{describe,jdbcType=VARCHAR}, content = #{content,jdbcType=VARCHAR} where id = #{id,jdbcType=INTEGER} </update> </mapper>
MessgaeMapper.java
<?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" > <mapper namespace="lcw.dao.MessgaeMapper" > <resultMap id="BaseResultMap" type="lcw.model.Messgae" > <id column="id" property="id" jdbcType="INTEGER" /> <result column="title" property="title" jdbcType="VARCHAR" /> <result column="describe" property="describe" jdbcType="VARCHAR" /> <result column="content" property="content" jdbcType="VARCHAR" /> </resultMap> <sql id="Base_Column_List" > id, title, describe, content </sql> <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" > select <include refid="Base_Column_List" /> from message where id = #{id,jdbcType=INTEGER} </select> <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" > delete from message where id = #{id,jdbcType=INTEGER} </delete> <insert id="insert" parameterType="lcw.model.Messgae" > insert into message (id, title, describe, content) values (#{id,jdbcType=INTEGER}, #{title,jdbcType=VARCHAR}, #{describe,jdbcType=VARCHAR}, #{content,jdbcType=VARCHAR}) </insert> <insert id="insertSelective" parameterType="lcw.model.Messgae" > insert into message <trim prefix="(" suffix=")" suffixOverrides="," > <if test="id != null" > id, </if> <if test="title != null" > title, </if> <if test="describe != null" > describe, </if> <if test="content != null" > content, </if> </trim> <trim prefix="values (" suffix=")" suffixOverrides="," > <if test="id != null" > #{id,jdbcType=INTEGER}, </if> <if test="title != null" > #{title,jdbcType=VARCHAR}, </if> <if test="describe != null" > #{describe,jdbcType=VARCHAR}, </if> <if test="content != null" > #{content,jdbcType=VARCHAR}, </if> </trim> </insert> <update id="updateByPrimaryKeySelective" parameterType="lcw.model.Messgae" > update message <set > <if test="title != null" > title = #{title,jdbcType=VARCHAR}, </if> <if test="describe != null" > describe = #{describe,jdbcType=VARCHAR}, </if> <if test="content != null" > content = #{content,jdbcType=VARCHAR}, </if> </set> where id = #{id,jdbcType=INTEGER} </update> <update id="updateByPrimaryKey" parameterType="lcw.model.Messgae" > update message set title = #{title,jdbcType=VARCHAR}, describe = #{describe,jdbcType=VARCHAR}, content = #{content,jdbcType=VARCHAR} where id = #{id,jdbcType=INTEGER} </update> </mapper>
转载于：https://www.cnblogs.com/lichenwei/p/4145696.html
使用Mybatis-Generator自动生成Dao、Model、Mapping相关文件
原文：https://www.cnblogs.com/liuxiaochong/p/13627434.html