8.逆向工程

1. Mybatis的逆向工程(generator). 由表帮我们来生成dao,bean,xml映射文件。

http://www.mybatis.org/generator/index.html。

1.  引入mybatis-generator的jar包

 2. 创建generator的配置文件。

        3. 运行generator

        2. 创建generator的配置文件。

<?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">
<!-- generator的配置文件 -->
<generatorConfiguration>
 <!-- mysql驱动jar所在的位置 -->
  <classPathEntry location="C:\javaHouse\mybatis04\lib\mysql-connector-java-5.1.47.jar" />
  
  <!-- 数据源信息 -->
  <context id="DB2Tables" targetRuntime="MyBatis3">
      <!-- 默认不加注释 -->
      <commentGenerator>
          <property name="suppressAllComments" value="true" />
    </commentGenerator>
  
    <jdbcConnection driverClass="com.mysql.jdbc.Driver"
        connectionURL="jdbc:mysql://localhost:3306/mybatis"
        userId="root"
        password="root">
    </jdbcConnection>

    <javaTypeResolver >
      <property name="forceBigDecimals" value="false" />
    </javaTypeResolver>
    
    <!-- 生产的实体类所在的位置 -->
    <javaModelGenerator targetPackage="com.zhiyou100.wc.bean" targetProject="./src">
      <property name="enableSubPackages" value="true" />
      <property name="trimStrings" value="true" />
    </javaModelGenerator>
    <!-- 生成的映射文件所在的位置 -->
    <sqlMapGenerator targetPackage="com.zhiyou100.wc.mapper"  targetProject="./resources">
      <property name="enableSubPackages" value="true" />
    </sqlMapGenerator>
    <!-- 生成的dao 文件所在的位置 -->
    <javaClientGenerator type="XMLMAPPER" targetPackage="com.zhiyou100.wc.dao"  targetProject="./src">
      <property name="enableSubPackages" value="true" />
    </javaClientGenerator>

    <!-- 某张表与实体类的对应关系
          schema：该表所在的数据库
          tableName:表名
          domainObjectName：实体类名
     -->
    <table schema="mybatis" tableName="users" domainObjectName="Users" 
    enableCountByExample="false" enableSelectByExample="false" enableDeleteByExample="false" enableUpdateByExample="false">
      <property name="useActualColumnNames" value="true"/>
      <generatedKey column="ID" sqlStatement="DB2" identity="true" />
      <columnOverride column="DATE_FIELD" property="startDate" />
      <ignoreColumn column="FRED" />
      <columnOverride column="LONG_VARCHAR_FIELD" jdbcType="VARCHAR" />
    </table>

  </context>
</generatorConfiguration>

  3. 运行generator

package com.zhiyou100.wc.test;

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;
//Ctrl+Shift+o 导包的快捷键
public class TestGRT {
    public static void main(String[] args) throws Exception{
       List<String> warnings = new ArrayList<String>();
       boolean overwrite = true;
       File configFile = new File("generator.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);
    }

}