外文文獻(xiàn)-java family account management system家庭收支管理系統(tǒng)

畢業(yè)設(shè)計(jì)外文文獻(xiàn)原文及譯文JAVAFAMILYACCOUNTMANAGEMENTSYSTEM家庭收支管理系統(tǒng)學(xué)生姓名學(xué)號(hào)系別計(jì)算機(jī)系專業(yè)計(jì)算機(jī)科學(xué)與技術(shù)指導(dǎo)教師2015年5月JAVAFAMILYACCOUNTMANAGEMENTSYSTEMIFJAVAIS,INFACT,YETANOTHERCOMPUTERPROGRAMMINGLANGUAGE,YOUMAYQUESTIONWHYITISSOIMPORTANTANDWHYITISBEINGPROMOTEDASAREVOLUTIONARYSTEPINCOMPUTERPROGRAMMINGTHEANSWERISNTIMMEDIATELYOBVIOUSIFYOURECOMINGFROMATRADITIONALPROGRAMMINGPERSPECTIVEALTHOUGHJAVAISVERYUSEFULFORSOLVINGTRADITIONALSTANDALONEPROGRAMMINGPROBLEMS,ITISALSOIMPORTANTBECAUSEITWILLSOLVEPROGRAMMINGPROBLEMSONTHEWORLDWIDEWEB1CLIENTSIDEPROGRAMMINGTHEWEBSINITIALSERVERBROWSERDESIGNPROVIDEDFORINTERACTIVECONTENT,BUTTHEINTERACTIVITYWASCOMPLETELYPROVIDEDBYTHESERVERTHESERVERPRODUCEDSTATICPAGESFORTHECLIENTBROWSER,WHICHWOULDSIMPLYINTERPRETANDDISPLAYTHEMBASICHTMLCONTAINSSIMPLEMECHANISMSFORDATAGATHERINGTEXTENTRYBOXES,CHECKBOXES,RADIOBOXES,LISTSANDDROPDOWNLISTS,ASWELLASABUTTONTHATCANONLYBEPROGRAMMEDTORESETTHEDATAONTHEFORMOR“SUBMIT”THEDATAONTHEFORMBACKTOTHESERVERTHISSUBMISSIONPASSESTHROUGHTHECOMMONGATEWAYINTERFACECGIPROVIDEDONALLWEBSERVERSTHETEXTWITHINTHESUBMISSIONTELLSCGIWHATTODOWITHITTHEMOSTCOMMONACTIONISTORUNAPROGRAMLOCATEDONTHESERVERINADIRECTORYTHATSTYPICALLYCALLED“CGIBIN”IFYOUWATCHTHEADDRESSWINDOWATTHETOPOFYOURBROWSERWHENYOUPUSHABUTTONONAWEBPAGE,YOUCANSOMETIMESSEE“CGIBIN”WITHINALLTHEGOBBLEDYGOOKTHERETHESEPROGRAMSCANBEWRITTENINMOSTLANGUAGESPERLISACOMMONCHOICEBECAUSEITISDESIGNEDFORTEXTMANIPULATIONANDISINTERPRETED,SOITCANBEINSTALLEDONANYSERVERREGARDLESSOFPROCESSOROROPERATINGSYSTEMMANYPOWERFULWEBSITESTODAYAREBUILTSTRICTLYONCGI,ANDYOUCANINFACTDONEARLYANYTHINGWITHITHOWEVER,WEBSITESBUILTONCGIPROGRAMSCANRAPIDLYBECOMEOVERLYCOMPLICATEDTOMAINTAIN,ANDTHEREISALSOTHEPROBLEMOFRESPONSETIMETHERESPONSEOFACGIPROGRAMDEPENDSONHOWMUCHDATAMUSTBESENT,ASWELLASTHELOADONBOTHTHESERVERANDTHEINTERNETONTOPOFTHIS,STARTINGACGIPROGRAMTENDSTOBESLOWTHEINITIALDESIGNERSOFTHEWEBDIDNOTFORESEEHOWRAPIDLYTHISBANDWIDTHWOULDBEEXHAUSTEDFORTHEKINDSOFAPPLICATIONSPEOPLEDEVELOPEDFOREXAMPLE,ANYSORTOFDYNAMICGRAPHINGISNEARLYIMPOSSIBLETOPERFORMWITHCONSISTENCYBECAUSEAGIFFILEMUSTBECREATEDANDMOVEDFROMTHESERVERTOTHECLIENTFOREACHVERSIONOFTHEGRAPHANDYOUVENODOUBTHADDIRECTEXPERIENCEWITHSOMETHINGASSIMPLEASVALIDATINGTHEDATAONANINPUTFORMYOUPRESSTHESUBMITBUTTONONAPAGETHEDATAISSHIPPEDBACKTOTHESERVERTHESERVERSTARTSACGIPROGRAMTHATDISCOVERSANERROR,FORMATSANHTMLPAGEINFORMINGYOUOFTHEERROR,ANDTHENSENDSTHEPAGEBACKTOYOUYOUMUSTTHENBACKUPAPAGEANDTRYAGAINNOTONLYISTHISSLOW,ITSINELEGANTTHESOLUTIONISCLIENTSIDEPROGRAMMINGMOSTMACHINESTHATRUNWEBBROWSERSAREPOWERFULENGINESCAPABLEOFDOINGVASTWORK,ANDWITHTHEORIGINALSTATICHTMLAPPROACHTHEYARESITTINGTHERE,JUSTIDLYWAITINGFORTHESERVERTODISHUPTHENEXTPAGECLIENTSIDEPROGRAMMINGMEANSTHATTHEWEBBROWSERISHARNESSEDTODOWHATEVERWORKITCAN,ANDTHERESULTFORTHEUSERISAMUCHSPEEDIERANDMOREINTERACTIVEEXPERIENCEATYOURWEBSITETHEPROBLEMWITHDISCUSSIONSOFCLIENTSIDEPROGRAMMINGISTHATTHEYARENTVERYDIFFERENTFROMDISCUSSIONSOFPROGRAMMINGINGENERALTHEPARAMETERSAREALMOSTTHESAME,BUTTHEPLATFORMISDIFFERENTAWEBBROWSERISLIKEALIMITEDOPERATINGSYSTEMINTHEEND,YOUMUSTSTILLPROGRAM,ANDTHISACCOUNTSFORTHEDIZZYINGARRAYOFPROBLEMSANDSOLUTIONSPRODUCEDBYCLIENTSIDEPROGRAMMINGTHERESTOFTHISSECTIONPROVIDESANOVERVIEWOFTHEISSUESANDAPPROACHESINCLIENTSIDEPROGRAMMING2PLUGINSONEOFTHEMOSTSIGNIFICANTSTEPSFORWARDINCLIENTSIDEPROGRAMMINGISTHEDEVELOPMENTOFTHEPLUGINTHISISAWAYFORAPROGRAMMERTOADDNEWFUNCTIONALITYTOTHEBROWSERBYDOWNLOADINGAPIECEOFCODETHATPLUGSITSELFINTOTHEAPPROPRIATESPOTINTHEBROWSERITTELLSTHEBROWSER“FROMNOWONYOUCANPERFORMTHISNEWACTIVITY”YOUNEEDTODOWNLOADTHEPLUGINONLYONCESOMEFASTANDPOWERFULBEHAVIORISADDEDTOBROWSERSVIAPLUGINS,BUTWRITINGAPLUGINISNOTATRIVIALTASK,ANDISNTSOMETHINGYOUDWANTTODOASPARTOFTHEPROCESSOFBUILDINGAPARTICULARSITETHEVALUEOFTHEPLUGINFORCLIENTSIDEPROGRAMMINGISTHATITALLOWSANEXPERTPROGRAMMERTODEVELOPANEWLANGUAGEANDADDTHATLANGUAGETOABROWSERWITHOUTTHEPERMISSIONOFTHEBROWSERMANUFACTURERTHUS,PLUGINSPROVIDEA“BACKDOOR”THATALLOWSTHECREATIONOFNEWCLIENTSIDEPROGRAMMINGLANGUAGESALTHOUGHNOTALLLANGUAGESAREIMPLEMENTEDASPLUGINS3SCRIPTINGLANGUAGESPLUGINSRESULTEDINANEXPLOSIONOFSCRIPTINGLANGUAGESWITHASCRIPTINGLANGUAGEYOUEMBEDTHESOURCECODEFORYOURCLIENTSIDEPROGRAMDIRECTLYINTOTHEHTMLPAGE,ANDTHEPLUGINTHATINTERPRETSTHATLANGUAGEISAUTOMATICALLYACTIVATEDWHILETHEHTMLPAGEISBEINGDISPLAYEDSCRIPTINGLANGUAGESTENDTOBEREASONABLYEASYTOUNDERSTANDAND,BECAUSETHEYARESIMPLYTEXTTHATISPARTOFANHTMLPAGE,THEYLOADVERYQUICKLYASPARTOFTHESINGLESERVERHITREQUIREDTOPROCURETHATPAGETHETRADEOFFISTHATYOURCODEISEXPOSEDFOREVERYONETOSEEANDSTEALGENERALLY,HOWEVER,YOUARENTDOINGAMAZINGLYSOPHISTICATEDTHINGSWITHSCRIPTINGLANGUAGESSOTHISISNOTTOOMUCHOFAHARDSHIPTHISPOINTSOUTTHATTHESCRIPTINGLANGUAGESUSEDINSIDEWEBBROWSERSAREREALLYINTENDEDTOSOLVESPECIFICTYPESOFPROBLEMS,PRIMARILYTHECREATIONOFRICHERANDMOREINTERACTIVEGRAPHICALUSERINTERFACESGUISHOWEVER,ASCRIPTINGLANGUAGEMIGHTSOLVE80PERCENTOFTHEPROBLEMSENCOUNTEREDINCLIENTSIDEPROGRAMMINGYOURPROBLEMSMIGHTVERYWELLFITCOMPLETELYWITHINTHAT80PERCENT,ANDSINCESCRIPTINGLANGUAGESCANALLOWEASIERANDFAST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AGEANDSENDSTOYOUASTHERESULTOFCOURSE,IFTHECLIENTHASMOREINTELLIGENCEVIAJAVAORASCRIPTINGLANGUAGE,THERAWDATACANBESENTANDFORMATTEDATTHECLIENTEND,WHICHWILLBEFASTERANDLESSLOADONTHESERVERORYOUMIGHTWANTTOREGISTERYOURNAMEINADATABASEWHENYOUJOINAGROUPORPLACEANORDER,WHICHWILLINVOLVECHANGESTOTHATDATABASETHESEDATABASEREQUESTSMUSTBEPROCESSEDVIASOMECODEONTHESERVERSIDE,WHICHISGENERALLYREFERREDTOASSERVERSIDEPROGRAMMINGTRADITIONALLY,SERVERSIDEPROGRAMMINGHASBEENPERFORMEDUSINGPERLANDCGISCRIPTS,BUTMORESOPHISTICATEDSYSTEMSHAVEBEENAPPEARINGTHESEINCLUDEJAVABASEDWEBSERVERSTHATALLOWYOUTOPERFORMALLYOURSERVERSIDEPROGRAMMINGINJAVABYWRITINGWHATARECALLEDSERVLETSSERVLETSANDTHEIROFFSPRING,JSPS,ARETWOOFTHEMOSTCOMPELLINGREASONSTHATCOMPANIESWHODEVELOPWEBSITESAREMOVINGTOJAVA,ESPECIALLYBECAUSETHEYELIMINATETHEPROBLEMSOFDEALINGWITHDIFFERENTLYABLEDBROWSERSJAVAFAMILYACCOUNTMANAGEMENTSYSTEMJAVAFAMILYACCOUNTMANAGEMENTSYSTEM家庭收支管理系統(tǒng)既然JAVA不過(guò)另一種類型的程序設(shè)計(jì)語(yǔ)言，大家可能會(huì)奇怪它為什么值得如此重視，為什么還有這么多的人認(rèn)為它是計(jì)算機(jī)程序設(shè)計(jì)的一個(gè)里程碑呢如果您來(lái)自一個(gè)傳統(tǒng)的程序設(shè)計(jì)背景，那么答案在剛開(kāi)始的時(shí)候并不是很明顯。JAVA除了可解決傳統(tǒng)的程序設(shè)計(jì)問(wèn)題以外，還能解決WORLDWIDEWEB萬(wàn)維網(wǎng)上的編程問(wèn)題。1客戶端編程WEB最初采用的“服務(wù)器瀏覽器”方案可提供交互式內(nèi)容，但這種交互能力完全由服務(wù)器提供，為服務(wù)器和因特網(wǎng)帶來(lái)了不小的負(fù)擔(dān)。服務(wù)器一般為客戶瀏覽器產(chǎn)生靜態(tài)網(wǎng)頁(yè)，由后者簡(jiǎn)單地解釋并顯示出來(lái)?；綡TML語(yǔ)言提供了簡(jiǎn)單的數(shù)據(jù)收集機(jī)制文字輸入框、復(fù)選框、單選鈕、列表以及下拉列表等，另外還有一個(gè)按鈕，只能由程序規(guī)定重新設(shè)置表單中的數(shù)據(jù)，以便回傳給服務(wù)器。用戶提交的信息通過(guò)所有WEB服務(wù)器均能支持的“通用網(wǎng)關(guān)接口”（CGI）回傳到服務(wù)器。包含在提交數(shù)據(jù)中的文字指示CGI該如何操作。最常見(jiàn)的行動(dòng)是運(yùn)行位于服務(wù)器的一個(gè)程序。那個(gè)程序一般保存在一個(gè)名為“CGIBIN”的目錄中（按下WEB頁(yè)內(nèi)的一個(gè)按鈕時(shí)，請(qǐng)注意一下瀏覽器頂部的地址窗，經(jīng)常都能發(fā)現(xiàn)“CGIBIN”的字樣）。大多數(shù)語(yǔ)言都可用來(lái)編制這些程序，但其中最常見(jiàn)的是PERL。這是由于PERL是專為文字的處理及解釋而設(shè)計(jì)的，所以能在任何服務(wù)器上安裝和使用，無(wú)論采用的處理器或操作系統(tǒng)是什么。2插件朝客戶端編程邁進(jìn)的時(shí)候，最重要的一個(gè)問(wèn)題就是插件的設(shè)計(jì)。利用插件，程序員可以方便地為瀏覽器添加新功能，用戶只需下載一些代碼，把它們“插入”瀏覽器的適當(dāng)位置即可。這些代碼的作用是告訴瀏覽器“從現(xiàn)在開(kāi)始，你可以進(jìn)行這些新活動(dòng)了”（僅需下載這些插入一次）。有些快速和功能強(qiáng)大的行為是通過(guò)插件添加到瀏覽器的。但插件的編寫(xiě)并不是一件簡(jiǎn)單的任務(wù)。在我們構(gòu)建一個(gè)特定的站點(diǎn)時(shí)，可能并不希望涉及這方面的工作。對(duì)客戶端程序設(shè)計(jì)來(lái)說(shuō)，插件的價(jià)值在于它允許專業(yè)程序員設(shè)計(jì)出一種新的語(yǔ)言，并將那種語(yǔ)言添加到瀏覽器，同時(shí)不必經(jīng)過(guò)瀏覽器原創(chuàng)者的許可。由此可以看出，插件實(shí)際是瀏覽器的一個(gè)“后門”，允許創(chuàng)建新的客戶端程序設(shè)計(jì)語(yǔ)言（盡管并非所有語(yǔ)言都是作為插件實(shí)現(xiàn)的）。3腳本編制語(yǔ)言插件造成了腳本編制語(yǔ)言的爆炸性增長(zhǎng)。通過(guò)這種腳本語(yǔ)言，可將用于自己客戶端程序的源碼直接插入HTML頁(yè)，而對(duì)那種語(yǔ)言進(jìn)行解釋的插件會(huì)在HTML頁(yè)顯示的時(shí)候自動(dòng)激活。腳本語(yǔ)言一般都傾向于盡量簡(jiǎn)化，易于理解。而且由于它們是從屬于HTML頁(yè)的一些簡(jiǎn)單正文，所以只需向服務(wù)器發(fā)出對(duì)那個(gè)頁(yè)的一次請(qǐng)求，即可非常快地載入。缺點(diǎn)是我們的代碼全部暴露在人們面前。另一方面，由于通常不用腳本編制語(yǔ)言做過(guò)分復(fù)雜的事情，所以這個(gè)問(wèn)題暫且可以放在一邊。腳本語(yǔ)言真正面向的是特定類型問(wèn)題的解決，其中主要涉及如何創(chuàng)建更豐富、更具有互動(dòng)能力的圖形用戶界面（GUI）。然而，腳本語(yǔ)言也許能解決客戶端編程中80的問(wèn)題。你碰到的問(wèn)題可能完全就在那80里面。而且由于腳本編制語(yǔ)言的宗旨是盡可能地簡(jiǎn)化與快速，所以在考慮其他更復(fù)雜的方案之前（如JAVA及ACTIVEX），首先應(yīng)想一下腳本語(yǔ)言是否可行。目前討論得最多的腳本編制語(yǔ)言包括JAVASCRIPT（它與JAVA沒(méi)有任何關(guān)系；之所以叫那個(gè)名字，完全是一種市場(chǎng)策略）、VBSCRIPT（同VISUALBASIC很相似）以及TCL/TK（來(lái)源于流行的跨平臺(tái)GUI構(gòu)造語(yǔ)言）。當(dāng)然還有其他許多語(yǔ)言，也有許多正在開(kāi)發(fā)中。JAVASCRIPT也許是日常用的，它得到的支持也最全面。無(wú)論NETSCAPENAVIGATOR，MICROSOFTINTERNETEXPLORER，還是OPERA，目前都提供了對(duì)JAVASCRIPT的支持。除此以外，市面上講述JAVASCRIPT的書(shū)籍也要比講述其他語(yǔ)言的書(shū)多得多。有些工具還能利用JAVASCRIPT自動(dòng)產(chǎn)生網(wǎng)頁(yè)。當(dāng)然，如果你已經(jīng)有VISUALBASIC或者TCL/TK的深厚功底，當(dāng)然用它們要簡(jiǎn)單得多，起碼可以避免學(xué)習(xí)新語(yǔ)言的煩惱（解決WEB方面的問(wèn)題就已經(jīng)夠讓人頭痛了）。4JAVA如果說(shuō)一種腳本編制語(yǔ)言能解決80的客戶端程序設(shè)計(jì)問(wèn)題，那么剩下的20又該怎么辦呢它們屬于一些高難度的問(wèn)題嗎目前最流行的方案就是JAVA。它不僅是一種功能強(qiáng)大、高度安全、可以跨平臺(tái)使用以及國(guó)際通用的程序設(shè)計(jì)語(yǔ)言，也是一種具有旺盛生命力的語(yǔ)言。對(duì)JAVA的擴(kuò)展是不斷進(jìn)行的，提供的語(yǔ)言特性和庫(kù)能夠很好地解決傳統(tǒng)語(yǔ)言不能解決的問(wèn)題，比如多線程操作、數(shù)據(jù)庫(kù)訪問(wèn)、連網(wǎng)程序設(shè)計(jì)以及分布式計(jì)算等等。JAVA通過(guò)“程序片”（APPLET）巧妙地解決了客戶端編程的問(wèn)題。程序片（或“小應(yīng)用程序”）是一種非常小的程序，只能在WEB瀏覽器中運(yùn)行。作為WEB頁(yè)的一部分，程序片代碼會(huì)自動(dòng)下載回來(lái)（這和網(wǎng)頁(yè)中的圖片差不多）。激活程序片后，它會(huì)執(zhí)行一個(gè)程序。程序片的一個(gè)優(yōu)點(diǎn)體現(xiàn)在通過(guò)程序片，一旦用戶需要客戶軟件，軟件就可從服務(wù)器自動(dòng)下載回來(lái)。它們能自動(dòng)取得客戶軟件的最新版本，不會(huì)出錯(cuò)，也沒(méi)有重新安裝的麻煩。由于JAVA的設(shè)計(jì)原理，程序員只需要?jiǎng)?chuàng)建程序的一個(gè)版本，那個(gè)程序能在幾乎所有計(jì)算機(jī)以及安裝了JAVA解釋器的瀏覽器中運(yùn)行。由于JAVA是一種全功能的編程語(yǔ)言，所以在向服