在做基于SSM框架时，因用的是全注解模式开发，在做些查询+分页工作时Mybatis注解并不能很好的进行sql编写，因而用到了这个java类，对实现了sql语句的拼接。(In the fr a mework based on SSM, because of using the full annotation model development, doing some work for the preparation of SQL paging query + Mybatis annotation is not very good, so use the Java class to achieve splicing of the SQL statement.)