在IntelliJ IDEA中使用Mybatis-generator插件快速生成代码

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在IntelliJ IDEA中使用Mybatis-generator插件快速生成代码

在pom.xml文件中输入如下内容:

<?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>dblab</groupId>
    <artifactId>MybatisGenerator</artifactId>
    <version>1.0-SNAPSHOT</version>
    <build>
        <plugins>
            <plugin>
                <groupId>org.mybatis.generator</groupId>
                <artifactId>mybatis-generator-maven-plugin</artifactId>
                <version>1.3.5</version>
                <dependencies>
                    <dependency>
                        <groupId>log4j</groupId>
                        <artifactId>log4j</artifactId>
                        <version>1.2.17</version>
                    </dependency>
                    <dependency>
                        <groupId>org.mybatis</groupId>
                        <artifactId>mybatis</artifactId>
                        <version>3.2.6</version>
                    </dependency>
                    <dependency>
                        <groupId>mysql</groupId>
                        <artifactId>mysql-connector-java</artifactId>
                        <version>5.1.40</version>
                    </dependency>
                </dependencies>
            </plugin>
        </plugins>
    </build>
</project>

创建generatorConfig.xml,在里面输入如下内容:

<?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>
    <context id="testTables" targetRuntime="MyBatis3">
        <commentGenerator>
            <!-- 是否去除自动生成的注释 true:是 : false:否 -->
            <property name="suppressAllComments" value="true" />
        </commentGenerator>
        <!--数据库连接的信息:驱动类、连接地址、用户名、密码 -->
        <jdbcConnection driverClass="com.mysql.jdbc.Driver"
                        connectionURL="jdbc:mysql://localhost:3306/test" userId="root"
                        password="123456">
        </jdbcConnection>
        <!-- <jdbcConnection driverClass="oracle.jdbc.OracleDriver"
            connectionURL="jdbc:oracle:thin:@127.0.0.1:1521:yycg"
            userId="yycg"
            password="yycg">
        </jdbcConnection> -->

        <!-- 默认false,把JDBC DECIMAL 和 NUMERIC 类型解析为 Integer,为 true时把JDBC DECIMAL 和
            NUMERIC 类型解析为java.math.BigDecimal -->
        <javaTypeResolver>
            <property name="forceBigDecimals" value="false" />
        </javaTypeResolver>

        <!-- targetProject:生成PO类的位置 -->
        <javaModelGenerator targetPackage="po"
                            targetProject="src/main/java">
            <!-- enableSubPackages:是否让schema作为包的后缀 -->
            <property name="enableSubPackages" value="false" />
            <!-- 从数据库返回的值被清理前后的空格 -->
            <property name="trimStrings" value="true" />
        </javaModelGenerator>
        <!-- targetProject:mapper映射文件生成的位置 -->
        <sqlMapGenerator targetPackage="mapper"
                         targetProject="src/main/java">
            <!-- enableSubPackages:是否让schema作为包的后缀 -->
            <property name="enableSubPackages" value="false" />
        </sqlMapGenerator>
        <!-- targetPackage:mapper接口生成的位置 -->
        <javaClientGenerator type="XMLMAPPER"
                             targetPackage="mapper"
                             targetProject="src/main/java">
            <!-- enableSubPackages:是否让schema作为包的后缀 -->
            <property name="enableSubPackages" value="false" />
        </javaClientGenerator>
        <!-- 指定数据库表 -->
        <table tableName="student"></table>

        <!-- <table schema="" tableName="sys_user"></table>
        <table schema="" tableName="sys_role"></table>
        <table schema="" tableName="sys_permission"></table>
        <table schema="" tableName="sys_user_role"></table>
        <table schema="" tableName="sys_role_permission"></table> -->

        <!-- 有些表的字段需要指定java类型
         <table schema="" tableName="">
            <columnOverride column="" javaType="" />
        </table> -->
    </context>
</generatorConfiguration>

创建一个Generator.java文件,输入如下代码:

import java.io.File;
import java.util.ArrayList;
import java.util.List;

import org.mybatis.generator.api.MyBatisGenerator;
import org.mybatis.generator.config.Configuration;
import org.mybatis.generator.config.xml.ConfigurationParser;
import org.mybatis.generator.internal.DefaultShellCallback;

public class GeneratorSqlmap {

    public void generator() throws Exception{

        List<String> warnings = new ArrayList<String>();
        boolean overwrite = true;
        //指定 逆向工程配置文件
        File configFile = new File("src/main/resources/generatorConfig.xml");
        ConfigurationParser cp = new ConfigurationParser(warnings);
        Configuration config = cp.parseConfiguration(configFile);
        DefaultShellCallback callback = new DefaultShellCallback(overwrite);
        MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config,
                callback, warnings);
        myBatisGenerator.generate(null);

    }
    public static void main(String[] args) throws Exception {
        try {
            GeneratorSqlmap generatorSqlmap = new GeneratorSqlmap();
            generatorSqlmap.generator();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

编译以后,Mybatis-generator自动生成的代码包括:

一个Student.java代码文件,内容如下:

package po;
public class Student {
    private String sno;
    private String sname;
    public String getSno() {
        return sno;
    }

    public void setSno(String sno) {
        this.sno = sno == null ? null : sno.trim();
    }

    public String getSname() {
        return sname;
    }

    public void setSname(String sname) {
        this.sname = sname == null ? null : sname.trim();
    }
}

一个StudentMapper.java文件,里面的内容如下:

package mapper;

import java.util.List;
import org.apache.ibatis.annotations.Param;
import po.Student;
import po.StudentExample;

public interface StudentMapper {
    long countByExample(StudentExample example);

    int deleteByExample(StudentExample example);

    int insert(Student record);

    int insertSelective(Student record);

    List<Student> selectByExample(StudentExample example);

    int updateByExampleSelective(@Param("record") Student record, @Param("example") StudentExample example);

    int updateByExample(@Param("record") Student record, @Param("example") StudentExample example);
}

一个StudentMapper.xml文件,里面的内容如下:

<?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="mapper.StudentMapper">
  <resultMap id="BaseResultMap" type="po.Student">
    <result column="sno" jdbcType="CHAR" property="sno" />
    <result column="sname" jdbcType="CHAR" property="sname" />
  </resultMap>
  <sql id="Example_Where_Clause">
    <where>
      <foreach collection="oredCriteria" item="criteria" separator="or">
        <if test="criteria.valid">
          <trim prefix="(" prefixOverrides="and" suffix=")">
            <foreach collection="criteria.criteria" item="criterion">
              <choose>
                <when test="criterion.noValue">
                  and ${criterion.condition}
                </when>
                <when test="criterion.singleValue">
                  and ${criterion.condition} #{criterion.value}
                </when>
                <when test="criterion.betweenValue">
                  and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
                </when>
                <when test="criterion.listValue">
                  and ${criterion.condition}
                  <foreach close=")" collection="criterion.value" item="listItem" open="(" separator=",">
                    #{listItem}
                  </foreach>
                </when>
              </choose>
            </foreach>
          </trim>
        </if>
      </foreach>
    </where>
  </sql>
  <sql id="Update_By_Example_Where_Clause">
    <where>
      <foreach collection="example.oredCriteria" item="criteria" separator="or">
        <if test="criteria.valid">
          <trim prefix="(" prefixOverrides="and" suffix=")">
            <foreach collection="criteria.criteria" item="criterion">
              <choose>
                <when test="criterion.noValue">
                  and ${criterion.condition}
                </when>
                <when test="criterion.singleValue">
                  and ${criterion.condition} #{criterion.value}
                </when>
                <when test="criterion.betweenValue">
                  and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
                </when>
                <when test="criterion.listValue">
                  and ${criterion.condition}
                  <foreach close=")" collection="criterion.value" item="listItem" open="(" separator=",">
                    #{listItem}
                  </foreach>
                </when>
              </choose>
            </foreach>
          </trim>
        </if>
      </foreach>
    </where>
  </sql>
  <sql id="Base_Column_List">
    sno, sname
  </sql>
  <select id="selectByExample" parameterType="po.StudentExample" resultMap="BaseResultMap">
    select
    <if test="distinct">
      distinct
    </if>
    <include refid="Base_Column_List" />
    from student
    <if test="_parameter != null">
      <include refid="Example_Where_Clause" />
    </if>
    <if test="orderByClause != null">
      order by ${orderByClause}
    </if>
  </select>
  <delete id="deleteByExample" parameterType="po.StudentExample">
    delete from student
    <if test="_parameter != null">
      <include refid="Example_Where_Clause" />
    </if>
  </delete>
  <insert id="insert" parameterType="po.Student">
    insert into student (sno, sname)
    values (#{sno,jdbcType=CHAR}, #{sname,jdbcType=CHAR})
  </insert>
  <insert id="insertSelective" parameterType="po.Student">
    insert into student
    <trim prefix="(" suffix=")" suffixOverrides=",">
      <if test="sno != null">
        sno,
      </if>
      <if test="sname != null">
        sname,
      </if>
    </trim>
    <trim prefix="values (" suffix=")" suffixOverrides=",">
      <if test="sno != null">
        #{sno,jdbcType=CHAR},
      </if>
      <if test="sname != null">
        #{sname,jdbcType=CHAR},
      </if>
    </trim>
  </insert>
  <select id="countByExample" parameterType="po.StudentExample" resultType="java.lang.Long">
    select count(*) from student
    <if test="_parameter != null">
      <include refid="Example_Where_Clause" />
    </if>
  </select>
  <update id="updateByExampleSelective" parameterType="map">
    update student
    <set>
      <if test="record.sno != null">
        sno = #{record.sno,jdbcType=CHAR},
      </if>
      <if test="record.sname != null">
        sname = #{record.sname,jdbcType=CHAR},
      </if>
    </set>
    <if test="_parameter != null">
      <include refid="Update_By_Example_Where_Clause" />
    </if>
  </update>
  <update id="updateByExample" parameterType="map">
    update student
    set sno = #{record.sno,jdbcType=CHAR},
      sname = #{record.sname,jdbcType=CHAR}
    <if test="_parameter != null">
      <include refid="Update_By_Example_Where_Clause" />
    </if>
  </update>
</mapper>