<!--mysql-->
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <scope>runtime</scope>
    </dependency>
    <!-- mybatis依賴 -->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>3.4.6</version>
    </dependency>
    <!-- mybatis逆向工程依賴 -->
    <dependency>
      <groupId>org.mybatis.generator</groupId>
      <artifactId>mybatis-generator-core</artifactId>
      <version>1.3.7</version>
    </dependency>

<?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="DB2Tables" targetRuntime="MyBatis3">
     <!-- 去除生成的注解 -->
     <commentGenerator>
        <property name="suppressAllComments" value="true"/>
     </commentGenerator>
     <!-- 數(shù)據(jù)庫連接配置 -->
     <!-- 注意xml中不支持&，用&amp;代替 -->
     <jdbcConnection driverClass="com.mysql.cj.jdbc.Driver" 
     connectionURL="jdbc:mysql://rm-m5e130nm7h37n6v982o.mysql.rds.aliyuncs.com:3306/demo?useUnicode=true&amp;characterEncoding=utf8&amp;useSSL=false&amp;serverTimezone=GMT%2B8"
     userId="xxxxx" password="xxxxxx"></jdbcConnection>
     <!-- 處理NUMERIC和DECIMAL類型的策略 -->
     <javaTypeResolver>
         <property name="forceBigDecimals" value="false" />
     </javaTypeResolver>
     <!-- 配置pojo生成的位置 -->
     <javaModelGenerator targetPackage="com.ycz.pojo"  targetProject="src/main/java">
        <property name="enableSubPackages" value="true" />
        <property name="trimStrings" value="true" />
     </javaModelGenerator>
     <!-- 配置sql映射文件的生成位置 -->
     <sqlMapGenerator targetPackage="com.ycz.mapper" targetProject="src/main/resources">
        <property name="enableSubPackages" value="true" />
        <property name="trimStrings" value="true" />        
     </sqlMapGenerator>
     <!-- 配置dao接口的生成位置 -->
     <javaClientGenerator type="XMLMAPPER" targetPackage="com.ycz.dao" 
     targetProject="src/main/java">
        <property name="enableSubPackages" value="true" />
        <property name="trimStrings" value="true" />     
     </javaClientGenerator>
     <!-- 指定逆向依據(jù)的數(shù)據(jù)表 -->
     <table tableName="person" domainObjectName="Person"></table>
   </context>
 </generatorConfiguration>

public class GeneratorTest {
    public static void main(String[] args) throws Exception {
        List<String> warnings = new ArrayList<String>();
        boolean overwrite = true;
        File configFile = new File("src/main/resources/config/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);
        System.out.println("生成成功！");
    }
}

  <!-- 注意xml中不支持&，用&amp;代替 -->
        <jdbcConnection driverClass="com.mysql.cj.jdbc.Driver"
                        connectionURL="jdbc:mysql://localhost:3306/mybatis_demo?useUnicode=true&amp;characterEncoding=utf8&amp;useSSL=false&amp;serverTimezone=GMT%2B8"
                        userId="root" password="admin123">
            <!--在逆向生成時(shí)，除了會(huì)生成 User 類，還會(huì)生成一個(gè)繼承 User 類的UserWithBLOBs 類。
                加入此注解避免生成類的UserWithBLOBs-->
            <property name="nullCatalogMeansCurrent" value="true" />
        </jdbcConnection>

  <!-- 配置pojo生成的位置 -->
        <javaModelGenerator targetPackage="com.fckey.pojo"  targetProject="src/main/java">
            <property name="enableSubPackages" value="true" />
            <property name="trimStrings" value="true" />
        </javaModelGenerator>

  <!-- 配置sql映射文件的生成位置 -->
        <sqlMapGenerator targetPackage="com.fckey.mapper" targetProject="src/main/resources">
            <property name="enableSubPackages" value="true" />
            <property name="trimStrings" value="true" />
        </sqlMapGenerator>

 <!-- 配置dao接口的生成位置 -->
        <javaClientGenerator type="XMLMAPPER" targetPackage="com.fckey.mapper"
                             targetProject="src/main/java">
            <property name="enableSubPackages" value="true" />
            <property name="trimStrings" value="true" />
        </javaClientGenerator>

 <!-- 指定逆向依據(jù)的數(shù)據(jù)表 -->
        <table tableName="t_dept" domainObjectName="Dept"></table>
        <table tableName="t_emp" domainObjectName="Emp"></table>
        <table tableName="t_user" domainObjectName="User"></table>

public class GeneratorTest {
    public static void main(String[] args) throws Exception {
        List<String> warnings = new ArrayList<String>();
        boolean overwrite = true;
        File configFile = new File("src/main/resources/config/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);
        System.out.println("生成成功！");
    }
}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <settings>
        <setting name="mapUnderscoreToCamelCase" value="true"/>
        <setting name="lazyLoadingEnabled" value="true"/>
        <setting name="cacheEnabled" value="true"/>
    </settings>
    <typeAliases>
        <!--將當(dāng)前包下的所有類都配置別名-->
        <package name="com.fckey.mybatis.entity"/>
    </typeAliases>
    <!--設(shè)置連接數(shù)據(jù)庫的環(huán)境-->
    <environments default="development">
    <environment id="development">
        <transactionManager type="JDBC"/>
        <dataSource type="POOLED">
            <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
            <property name="url"
                      value="jdbc:mysql://localhost:3306/mybatis_demo"/>
            <!--注意：如果在建sql表單的時(shí)候選了字符集（如utf8），
            這里的value要改成：value="jdbc:mysql://localhost:3306/mybatis?characterEncoding=utf8"-->
            <property name="username" value="root"/>
            <property name="password" value="admin123"/>
        </dataSource>
    </environment>
</environments>
    <!--引入映射文件-->
    <mappers>
        <package name="com.fckey.mapper"/>
    </mappers>
</configuration>

   private static SqlSession getSqlSession() throws IOException {
    /*
       如果是想自動(dòng)的進(jìn)行提交，而不需要手動(dòng)的提交事務(wù)，可以在sqlSession()中傳入true，即可開啟自動(dòng)提交功能
     */
        // 加載核心配置文件
        InputStream is = Resources.getResourceAsStream("mybatis-config.xml");
        // 獲取sqlsessionfactorybuilder對(duì)象
        SqlSessionFactoryBuilder sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder();
        // 獲取sqlsessionFactory
        SqlSessionFactory sqlSessionFactory = sqlSessionFactoryBuilder.build(is);
        // 獲取sqlsession
        SqlSession sqlSession = sqlSessionFactory.openSession(true);
        return sqlSession;
    }
    @org.junit.Test
    public void test() throws IOException {
        SqlSession sqlSession = getSqlSession();
        EmpMapper mapper = sqlSession.getMapper(EmpMapper.class);
        List<Emp> emps = mapper.selectByExample(null);
        System.out.println(emps);
    }