spring-boot and mybatis working together, without the stinking help of mybatis-spring.

gistfile1.java

 @Bean SqlSessionFactory sqlSessionFactory() {
    TransactionFactory transactionFactory = new JdbcTransactionFactory();
    Environment environment = new Environment("dev", transactionFactory, dataSource());

    Configuration configuration = new Configuration(environment);

    // NOTE: you must register aliases before adding mappers.  
    configuration.getTypeAliasRegistry().registerAlias(MyClazz.class);

    // NOTE: you can add a package where your mappers reside or add one at a time.  
    configuration.addMapper(IMyClazzMapper.class);

    configuration.setMapUnderscoreToCamelCase(true);

    return new SqlSessionFactoryBuilder().build(configuration);
  }

  public interface IClazzMapper {
    MyClazz selectBySourceId( Integer sourceId );
  }

  <?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="com.mypackage.IMyClazzMapper">
   <select id="selectById" resultType="MyClazz">
    select id from my_table where id = #{id}
   </select>
 </mapper>

 public class MyClazzDAO {

  @Autowired SqlSessionFactory sessionFactory; 

  public MyClazz getById( final Integer Id ) {
    MyClazz myClazz = null;

    try (SqlSession session = sessionFactory.openSession()) {
      IMyClazzMapper myClazzMapper = session.getMapper(IMyClazzMapper.class);
      myClazz = myClazzMapper.selectById(id);
    }

    return myClazz;
  }
}