学习中....

   我们操作的是对象／类的引用（reference）。    存储数据data的五个地方：Registers. This is the fastest storage because it exists in a place different from that of other storage: inside the processor. Howeve...

object别名映射 -> 实体类： resultClass <select id=" selectAll" resultClass="AppLog">    select      ID as id,      TYPE as type,      DESCR as descr    from APP_LOG    where ID = #id#</select> ...

1. public static boolean isEmpty(String str) 　　判断某字符串是否为空，为空的标准是 str==null 或 str.length()==0 　　下面是 StringUtils 判断是否为空的示例： 　　StringUtils.isEmpty(null) = true 　　StringUtils.isEmpty("") = true 　　Str...