<?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">
<!-- 配置生成器 -->
<generatorConfiguration> 
   <!-- 引用外部配置文件 -->
   <properties resource="db.properties" />
  <!-- 
    在MBG工作的时候，需要额外加载的依赖包location属性指明加载jar/zip包的全路径 -->
  <!--
    <classPathEntry location="F:\.m2\repository\mysql\mysql-connector-java\5.1.38\mysql-connector-java-5.1.38.jar"/>
   -->
    <context id="MySqlContext" targetRuntime="MyBatis3" defaultModelType="flat">
      <!-- beginningDelimiter/endingDelimiter: 指明数据库的用于标记数据库对象名的符号，比如ORACLE是双引号，MYSQL默认是`反引号  -->
        <property name="beginningDelimiter" value="`"/>
        <property name="endingDelimiter" value="`"/>
        <!-- 生成的Java文件的编码 -->
        <property name="javaFileEncoding" value="UTF-8"/>
        <commentGenerator>
          <!-- suppressDate是去掉生成日期那行注释，suppressAllComments是去掉所有的注解 -->
            <property name="suppressDate" value="true"/>
            <!-- 在生成的实体类中附带表字段的注释  MBG1.3.3中新增的功能 -->
            <property name="addRemarkComments" value="true"/>
        </commentGenerator>
    <!-- 必须存在，使用这个配置链接数据库-->
        <jdbcConnection driverClass="${jdbc.driver}"
                        connectionURL="${jdbc.url}"
                        userId="${jdbc.username}"
                        password="${jdbc.password}">
              <!-- 这里面可以设置property属性，每一个property属性都设置到配置的Driver上 -->
        </jdbcConnection>
        <javaModelGenerator targetPackage="example.model" targetProject="src\main\java">
      <!-- 设置是否在getter方法中，对String类型字段调用trim()方法 -->
      <property name="trimStrings" value="true" />
        </javaModelGenerator>
        <sqlMapGenerator targetPackage="example.xml"  targetProject="src\main\resources">
        </sqlMapGenerator>
        <javaClientGenerator type="XMLMAPPER" targetPackage="example.dao"  targetProject="src\main\java">
        </javaClientGenerator>
        <table tableName="country">
            <generatedKey column="id" sqlStatement="MySql"/>
        </table>
     </context>
</generatorConfiguration>

package com.mybatis.generator;
import java.io.InputStream;
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;
/**
 * 
 * 
 * @ClassName: GeneratorCountry
 * 
 * @Description: 读取 MBG 配置生成代码
 * 
 * @author: Mr.Yang
 * 
 * @date: 2018年4月27日 下午23:31:42
 */
public class GeneratorCountry {
  public static void main(String[] args) throws Exception {
    // MBG 执行过程中的警告信息
    List<String> warnings = new ArrayList<String>();
    // 当生成的代码重复时，覆盖原代码
    boolean overwrite = true;
    // 读取MBG配置文件
    InputStream is = GeneratorCountry.class.getResourceAsStream("/generator/generatorConfig-country.xml");
    ConfigurationParser cp = new ConfigurationParser(warnings);
    Configuration config = cp.parseConfiguration(is);
    is.close();
    DefaultShellCallback callback = new DefaultShellCallback(overwrite);
    // 创建 MBG
    MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, callback, warnings);
    // 执行生成代码
    myBatisGenerator.generate(null);
    // 输出警告信息
    for (String warning : warnings) {
      System.out.println(warning);
    }
    System.out.println("Finshed");
  }
}

@Test
  public void updateByExampleSelectiveTest() {
    // 获取 sqlSession
    SqlSession sqlSession = getSqlSession();
    try {
      // 获取 CountryMapper 接口
      CountryMapper countryMapper = sqlSession.getMapper(CountryMapper.class);
      // 创建 Example 对象
      CountryExample example = new CountryExample();
      // 创建条件，只能有一个 createCriteria
      CountryExample.Criteria criteria = example.createCriteria();
      // 更新所有 id > 2 的国家
      criteria.andIdGreaterThan(2);
      // 创建一个要设置的对象
      Country country = new Country();
      // 将国家名字设置为 China
      country.setCountryname("China");
      // 执行查询
      countryMapper.updateByExampleSelective(country, example);
      // 在把符合条件的结果输出查看
      printCountryList(countryMapper.selectByExample(example));
    } finally {
      // 为了不影响数据，这里选择回滚
      sqlSession.rollback();
      // 不要忘记关闭 sqlSession
      sqlSession.close();
    }
  }

@Test
  public void deleteByExampleTest() {
    // 获取 sqlSession
    SqlSession sqlSession = getSqlSession();
    try {
      // 获取 CountryMapper 接口
      CountryMapper countryMapper = sqlSession.getMapper(CountryMapper.class);
      // 创建 Example 对象
      CountryExample example = new CountryExample();
      // 创建条件，只能有一个 createCriteria
      CountryExample.Criteria criteria = example.createCriteria();
      // 删除所有 id > 2 的国家
      criteria.andIdGreaterThan(2);
      // 执行查询
      countryMapper.deleteByExample(example);
      // 使用 countByExample 查询符合条件的数量，因为删除了，所以这里应该是 0
      Assert.assertEquals(0, countryMapper.countByExample(example));
    } finally {
      // 为了不影响数据，这里选择回滚
      sqlSession.rollback();
      // 不要忘记关闭 sqlSession
      sqlSession.close();
    }
  }

2018-04-28 15:49:43,236  INFO [main] (BaseMapperTest.java:26) - sessionFactory bulit successfully
2018-04-28 15:49:43,266  INFO [main] (BaseMapperTest.java:29) - reader close successfully
2018-04-28 15:49:43,503 DEBUG [main] (BaseJdbcLogger.java:145) - ==>  Preparing: delete from country WHERE ( id > ? ) 
2018-04-28 15:49:43,633 DEBUG [main] (BaseJdbcLogger.java:145) - ==> Parameters: 2(Integer)
2018-04-28 15:49:43,643 DEBUG [main] (BaseJdbcLogger.java:145) - <==    Updates: 3
2018-04-28 15:49:43,653 DEBUG [main] (BaseJdbcLogger.java:145) - ==>  Preparing: select count(*) from country WHERE ( id > ? ) 
2018-04-28 15:49:43,653 DEBUG [main] (BaseJdbcLogger.java:145) - ==> Parameters: 2(Integer)
2018-04-28 15:49:43,693 TRACE [main] (BaseJdbcLogger.java:151) - <==    Columns: count(*)
2018-04-28 15:49:43,693 TRACE [main] (BaseJdbcLogger.java:151) - <==        Row: 0
2018-04-28 15:49:43,693 DEBUG [main] (BaseJdbcLogger.java:145) - <==      Total: 1