EasyDBO是由简易java框架网(www.easyjf.com)开发的一个适合中小型软件数据库开发的java数据持久层框架,系统参考hibernate、JDO等,结合中小项目软件的开发实际,实现简单的Java对象到关系数据的映射。EasyDBO由于比较简单,比较适合于中小企业及个人开发使用,EasyDBO当前还处于测试阶段、是一个简易但不太成熟的对象-关系映射开源中间件。 EasyDBO的源代码非常简单,有一点Java知识的人基本上都能读懂,因此,选择EasyDBO作本文的示例主要目的在于让读者快速进入ORM系统的世界,理解对象-关系数据库实质及实现原理。 EasyDBO考虑的是最简单的对象-关系映射,简单到可以不使用任何配置文件就实现对象-关系的映射。EasyDBO源码主要包括com.easyjf.dbo、com.easyjf.dbo.config、com.easyjf.dbo.sql三个包。其中com.easyjf.dbo是框架的核心、实现了对象-关系的转换、JDBC API的封装以及用户接口支持等,com.easyjf.dbo.config实现配置文件的管理,com.easyjf.dbo.sql实现数据库的简单Sql语句的生成及多数据库支持的扩展。
上传时间: 2013-12-30
上传用户:change0329
数字运算,判断一个数是否接近素数 A Niven number is a number such that the sum of its digits divides itself. For example, 111 is a Niven number because the sum of its digits is 3, which divides 111. We can also specify a number in another base b, and a number in base b is a Niven number if the sum of its digits divides its value. Given b (2 <= b <= 10) and a number in base b, determine whether it is a Niven number or not. Input Each line of input contains the base b, followed by a string of digits representing a positive integer in that base. There are no leading zeroes. The input is terminated by a line consisting of 0 alone. Output For each case, print "yes" on a line if the given number is a Niven number, and "no" otherwise. Sample Input 10 111 2 110 10 123 6 1000 8 2314 0 Sample Output yes yes no yes no
上传时间: 2015-05-21
上传用户:daguda
The government of a small but important country has decided that the alphabet needs to be streamlined and reordered. Uppercase letters will be eliminated. They will issue a royal decree in the form of a String of B and A characters. The first character in the decree specifies whether a must come ( B )Before b in the new alphabet or ( A )After b . The second character determines the relative placement of b and c , etc. So, for example, "BAA" means that a must come Before b , b must come After c , and c must come After d . Any letters beyond these requirements are to be excluded, so if the decree specifies k comparisons then the new alphabet will contain the first k+1 lowercase letters of the current alphabet. Create a class Alphabet that contains the method choices that takes the decree as input and returns the number of possible new alphabets that conform to the decree. If more than 1,000,000,000 are possible, return -1. Definition
标签: government streamline important alphabet
上传时间: 2015-06-09
上传用户:weixiao99
电力系统在台稳定计算式电力系统不正常运行方式的一种计算。它的任务是已知电力系统某一正常运行状态和受到某种扰动,计算电力系统所有发电机能否同步运行 1运行说明: 请输入初始功率S0,形如a+bi 请输入无限大系统母线电压V0 请输入系统等值电抗矩阵B 矩阵B有以下元素组成的行矩阵 1正常运行时的系统直轴等值电抗Xd 2故障运行时的系统直轴等值电抗X d 3故障切除后的系统直轴等值电抗 请输入惯性时间常数Tj 请输入时段数N 请输入哪个时段发生故障Ni 请输入每时段间隔的时间dt
上传时间: 2015-06-13
上传用户:it男一枚
上下文无关文法(Context-Free Grammar, CFG)是一个4元组G=(V, T, S, P),其中,V和T是不相交的有限集,S∈V,P是一组有限的产生式规则集,形如A→α,其中A∈V,且α∈(V∪T)*。V的元素称为非终结符,T的元素称为终结符,S是一个特殊的非终结符,称为文法开始符。 设G=(V, T, S, P)是一个CFG,则G产生的语言是所有可由G产生的字符串组成的集合,即L(G)={x∈T* | Sx}。一个语言L是上下文无关语言(Context-Free Language, CFL),当且仅当存在一个CFG G,使得L=L(G)。 *⇒ 例如,设文法G:S→AB A→aA|a B→bB|b 则L(G)={a^nb^m | n,m>=1} 其中非终结符都是大写字母,开始符都是S,终结符都是小写字母。
标签: Context-Free Grammar CFG
上传时间: 2013-12-10
上传用户:gaojiao1999
We have a group of N items (represented by integers from 1 to N), and we know that there is some total order defined for these items. You may assume that no two elements will be equal (for all a, b: a<b or b<a). However, it is expensive to compare two items. Your task is to make a number of comparisons, and then output the sorted order. The cost of determining if a < b is given by the bth integer of element a of costs (space delimited), which is the same as the ath integer of element b. Naturally, you will be judged on the total cost of the comparisons you make before outputting the sorted order. If your order is incorrect, you will receive a 0. Otherwise, your score will be opt/cost, where opt is the best cost anyone has achieved and cost is the total cost of the comparisons you make (so your score for a test case will be between 0 and 1). Your score for the problem will simply be the sum of your scores for the individual test cases.
标签: represented integers group items
上传时间: 2016-01-17
上传用户:jeffery
摘要:本文是笔者根据数据库编程经验,利用C++语言的模板、继承、授权、多态等面向对象特性,借鉴命令模式,实现了对象在关系数据中的存储,降低应用系统与数据库之间的耦合,提高开发效率。
上传时间: 2016-02-01
上传用户:hjshhyy
The XML Toolbox converts MATLAB data types (such as double, char, struct, complex, sparse, logical) of any level of nesting to XML format and vice versa. For example, >> project.name = MyProject >> project.id = 1234 >> project.param.a = 3.1415 >> project.param.b = 42 becomes with str=xml_format(project, off ) "<project> <name>MyProject</name> <id>1234</id> <param> <a>3.1415</a> <b>42</b> </param> </project>" On the other hand, if an XML string XStr is given, this can be converted easily to a MATLAB data type or structure V with the command V=xml_parse(XStr).
标签: converts Toolbox complex logical
上传时间: 2016-02-12
上传用户:a673761058
Hibernate的精典实例,包含了所有对象对应关系的处理,包括一对一、一对多、多对多。简单掌握Hibernate最烦人的关系处理。
标签: Hibernate
上传时间: 2013-12-23
上传用户:manking0408
欢迎使用PB小助手。作为一名PB程序员,您是否有过为了查找某一语句而不辞辛劳地打开一个又一个事件或函数, 在其脚本中苦苦寻觅的痛苦经历;而为了找到某一变量或函数的定义,您不得不在错综复杂的对象继承关系中刨根溯源、 上下求索。有了PB小助手,这些问题都将迎刃而解。它能帮您在一大堆对象或脚本中迅速找到您想要的,快人一步,胜人一筹!
标签: 程序员
上传时间: 2014-01-06
上传用户:gdgzhym