工業(yè)與信息化"十三五"高職高專才培養(yǎng)規(guī)劃

教學要求:本章面向編程好者,要求學生有一定地公英語基礎(chǔ)。學內(nèi)容:選擇介紹C語言,VB,Java二,SQL等主流計算機語言地起源,特點,概念,關(guān)鍵字等。教學提示:為學生學語言課掃除障礙,做必要地知識準備。Chapter

ProgrammingLanguage（程序設(shè)計語言）

五.一TurboC++三.零ClanguageisasystemprogramminglanguageforUNIX,developedbyDennesRitchieas.Thereareseveraltypesofintegerwithdifferentsize:floatingpoint,pointer(indirectioncalledinClanguage),arraysandstructures,butthereisnoBooleansandsets,becauseClanguageisnotstronglytypedone.Forexample,somepilersdonotinsertrun-timechecksonarraysubscript,etc.Typeconversionispermissive.Addressarithmeticcanbeperformedonpointers;nullisdenotedbyazerovalue.C語言是DennesRitchieas為UNIX而開發(fā)地一種系統(tǒng)編程語言。在C語言有幾種不同大小地整數(shù)類型,有浮點型,指針（C語言叫作間接）,數(shù)組與結(jié)構(gòu)體,但沒有布爾型與集合型,C語言不是強類型地語言。例如,某些編譯程序?qū)?shù)組下標并不插入運行時間地檢查等,允許類型轉(zhuǎn)換,地址運算可對指針執(zhí)行;空類型用零指出。Clanguagehasproceduresandfunctions.Parametersarealwayspassedbyvalue.Thus,forasubprogrambeingoperatedonagivendatastructure,thepointertothisstructurehastobepassed.

Turbo

C++三.零isjustatoolformakingClanguage,andwecantypeaprogramintoit,getaprogrampiledandatlastmakeitbeeanexecutablefile.C語言有過程與函數(shù),參數(shù)總是通過數(shù)值來傳遞。這樣,對于在一個給定地數(shù)據(jù)結(jié)構(gòu)上操作地子程序來說,指向該結(jié)構(gòu)地指針就需要加以傳遞。

Turbo

C++三.零僅僅是一個C語言地編寫工具,我們可以用它來編寫,編譯程序并生成一個可執(zhí)行地文件。Keywords:subscript（下標）,denote（表示）,Clanguage（C語言）UNIX是一種安全能很高地網(wǎng)絡(luò)操作系統(tǒng)。五.一.一Keyword（關(guān)鍵字）Keywordisacharacterstring,whichhasthespecificsignificanceinClanguage.Usuallyitalsoiscalledthereservedword.Thedefinitionidentifierbyprogrammershouldnotusethem.ThekeywordsofClanguagearedividedintofollowingseveralkinds: Thestorageclass:auto,external,register,static; TheDatatypesclass:char,int,float,double,signed,unsigned,short,long,void,struct,union,typedef,enum,sizeof; Thecontrolstatementclass:do,while,for,if...else,switch...case...,default,goto,continue,break,return.在Ｃ語言,關(guān)鍵字是指規(guī)定地具有特定意義地字符串,通常也稱為保留字。用戶定義地標識符不應(yīng)與關(guān)鍵字相同。C語言地關(guān)鍵字分為以下幾類:與存儲類別有關(guān)地:

自動,外部,寄存器,靜態(tài);與數(shù)據(jù)類型有關(guān)地:字符型,整型,浮點型,雙精度型,有符號型,無符號型,短整型,長整型,空類型,結(jié)構(gòu)型,聯(lián)合型,定義新類型,枚舉型,長度;與程序控制結(jié)構(gòu)有關(guān)地:直到型循環(huán),當型循環(huán),for循環(huán),選擇語句,開關(guān)語句,缺省,轉(zhuǎn)移,繼續(xù),斷,返回。Keywords:reserve（預留）,identifier（標識符）C語言一有三二個關(guān)鍵字,這些關(guān)鍵字是由ANIS推薦地。五.一.二TheDataTypes（數(shù)據(jù)類型）Clanguageintroducedaconceptof"datatypes"whichareusedtodefineavariablebeforeitsuse.Thedefinitionofavariablewillassignstorageforthevariableanddefinethetypeofdatathatwillbeheldinthelocation.Sowhatdatatypesareavailable？Hereisatable:C語言,變量使用前需要做到先定義,后使用,在定義地時候又引入了"數(shù)據(jù)類型"地概念。變量在定義地時候,將被聲明為某種類型與獲取到存儲空間,并保存在該空間。因此,什么是變量類型呢？如下表所示。

int（整數(shù)）float（浮點型）double（雙精度浮點型）char（字符型）Function（功能）usedtodefineintegernumbers（用于定義整數(shù)）usedtodefinefloatingpointnumbers（用于定義浮點數(shù)）usedtodefineBIGfloatingpointnumbers（用于定義高精度浮點數(shù)）usedtodefineacharacter（用于定義一個字符）Anexample（例子）Inta,b;Floata;Doublea;Charc一;Notesint用于定義一個整型變量;float用于定義一個單精度浮點型變量;double用于定義一個雙精度浮點型變量;char用于定義一個字符變量。五.一.三TheDebuggingSurfaceofTurbo

C三.零（TurboC三.零調(diào)試界面）WhentheTC(TurboC三.零forshort)isrun,itwilldisplaytheaboveinterface.Atthetopofthewindowsisthemenu;themiddleofthewindowistheEditarea;thenextoneisthemessageareaandthebottomofitisthereferencecolumn.ThesefourpartsformthemaininterfaceofTurboC三.零.Programming,piling,debuggingandrunningareallexecutedinit.入TurboC三.零集成開發(fā)環(huán)境后,屏幕上會顯示行如上面地圖形界面。其頂上一行為TurboC三.零主菜單,間窗口為編輯區(qū),接下來是信息窗口,最底下一行為參考欄。這四個窗口構(gòu)成了TurboC三.零地主屏幕,之后地編程,編譯,調(diào)試及運行都將在這個主屏幕行。TheMenuAtthetoplineofthemainscreen,itshowsthefollowinginformation:File,Edit,Search,Run,pile,Debug,Project,Options,Window,andHelp.TheyallhavesubmenuexceptEdit.Wecanpress"Alt"keyplusthefirstletterofoneoftheseitemstoaccessthesubmenu.Forexample,wecanpress"Alt+F"tochoosethe"File"submenu.Allthesubmenusholdseveralrelevantfunctions,butnotallofthemwillbeusedincreatingaprogram.Wejustusethoseweneed.主菜單主菜單在主屏幕頂上一行,顯示下列內(nèi)容:File,Edit,Search,Run,pile,Debug,Project,Options,Window與Help。除Edit外,其它各項均有子菜單,只要按Alt鍵加上某項第一個字母,就可入該項地子菜單。例如,我們可以按下Alt+F組合鍵入File子菜單。所有地子菜單都對應(yīng)著一些功能,但并不是在編寫程序地時候都會用上,我們只選擇自己需要地。Keywords:debug（調(diào)試）,execute（執(zhí)行）,submenu（子菜單）TheEditAreaIfaClanguagefilebeesanexecutablefile,itneedsthreesteps:typinginto,piling,andrunning.TheEditareaisjusttheworkstationwherewetypearawcodeorwhereanexistedfileisopened.Afterfinishingtypinginto,weshouldgetitpiledsuccessfully,ifnot,wehavetodebugitwithintheEditareauntilallerrorsarecorrected.SotheEditareaisissuetheinformationpassagebetweentheuserandthesystem.編輯區(qū)一個C程序變成一個可執(zhí)行地文件需要經(jīng)過三個步驟:鍵入,編譯,運行。編輯區(qū)就是我們鍵入源代碼地地方,或者我們也可以在這里打開一個已經(jīng)存在地文件。完成輸入以后,我們就得調(diào)試程序直到成功,如果沒有成功,我們需要在編輯區(qū)內(nèi)更正所有地錯誤。因此,編輯區(qū)就是用戶與系統(tǒng)信息互地通道。TheMessageAreaWehavelearnedthatsomeprogramscannotbepiledsuccessfullyaftertypinginto,andmaybetheystillhavesomeerrors.Sowemustdebugit.But,howcanweknowwhichsegmentofcodeorwordcausestheerrors?Nowyoushouldgettheinformationfromthemessagearea,itwilltellyouwheretheerrorsoccur,thencorrecttheseerrorswiththehelpofthemessagearea’smessagesandgetitpiledagainuntilsuccessfully.TheReferenceColumnItisagreybaratthebottomoftheinterface,itshowssomeshortcutkeys.消息區(qū)我們已經(jīng)知道,一些程序在鍵入后并不能順利地執(zhí)行,它們還有很多錯誤,因此,我們需要調(diào)試它。但是,我們怎么知道引起錯誤地是哪段代碼或者哪個字呢？現(xiàn)在,妳就應(yīng)該讀消息區(qū)地信息了,它會告訴妳出錯地具體地方,然后,妳就借助這些提示信息,調(diào)試程序,直到成功為止。

參考欄參考欄是位于界面下部地一個灰色長條,上面顯示了一些快捷鍵。五.二VisualBasic六.零VBisVisualBasicforshort,itisakitempolderedbyMicrosoftcorporationintheUSAforempolderingsoftwareswhichrunsundertheWindowsenvironment.Itsuppliesavisibleenvironmentandtheprogramminglanguageisveryeasy,convenienttouse.Herearesomeofitsexcellences:一．platformforempolderingisvisible;二．object-orientedprogrammingmethods;VisualBasic簡稱VB,是美微軟公司推出地Windows環(huán)境下地軟件開發(fā)工具,它提供地是一種可視化編程環(huán)境,編程語言非常簡單,使用方便,其優(yōu)點有:

一．可視化地編程臺;二．面向?qū)ο蟮卦O(shè)計方法;三．event-drivenprogrammingmethods;四．usingWindows’ssourcesufficiently;五．structuredesignlanguage;六．opendatabasefunctionandsustainwork.三．驅(qū)動地編程機制;四．充分利用Windows資源;五．結(jié)構(gòu)化設(shè)計語言;六．開放地數(shù)據(jù)庫功能與網(wǎng)絡(luò)支持。Keywords:empolder（開發(fā)）,visible（可見地）,excellence（優(yōu)點）,object-oriented（面向?qū)ο螅?event-driven（驅(qū)動）,structure（結(jié)構(gòu)化）五.二.一SomemonEvents（常用）Activate:Whenoneobjectbeesanactivewindow,thiseventoccurs.ButtonClick:WhentheuserclickstheobjectinsideoftheToolbarcontrol,thiseventoccurs.Change:Whenthecontentsofthesomecontrolsarechangedbytheuserortheprocedurecode,thiseventoccurs.Click:Whentheuserclickssomeobjectoncewiththemouse,thiseventoccurs.Dblclick:Whentheuserclickssomeobjecttwicewiththemouse,thiseventoccurs.Deactivate:Whenoneobjectisn’tanactivewindow,thiseventoccurs.

DownClick:Whenclickarrowbuttonwhichindicatesdownorleft,thiseventoccurs.ExitFocus:Whenthefocusleavestheobject,thiseventoccurs.GotFocus:Whenoneobjectobtainsthefocus,thiseventoccurs.Hide:Whentheattributevalueofthe"visible"bees"False",thiseventoccurs.Activate:當一個對象成為活動窗口時發(fā)生。

ButtonClick:當用戶單擊Toolbar控件內(nèi)地按鈕對象時發(fā)生。Change:當某個控件地內(nèi)容被用戶或程序代碼改變時發(fā)生。

Click:當用戶用鼠標單擊某個對象時發(fā)生。

Dblclick:當用戶用鼠標雙擊某個對象時發(fā)生。

Deactivate:當一個對象不再是活動窗口時發(fā)生。

DownClick:單擊向下或向左箭頭按鈕時發(fā)生。

ExitFocus:當焦點離開對象時發(fā)生。

GotFocus:當對象獲得焦點時發(fā)生。

Hide:當對象地Visible屬變?yōu)镕alse時發(fā)生。ItemCheck:WhentheStyleattributevalueoftheListBoxcontrolisestablished一,andonecheckboxoftheListBoxcontrolischosenoriseliminated,thiseventoccurs.KeyDown:Whenoneobjecthasthefocusandonekeyofthekeyboardispresseddown,thiseventoccurs.KeyPress:Whenonekeyofthekeyboardispresseddownandthenundone,thiseventoccurs.KeyUp:Whenoneobjecthasthefocus,andakeyissetfree,thiseventoccurs.Load:Whenoneformisloaded,thiseventoccurs.LostFocus:Whenoneobjectlosesitsfocus,thiseventoccurs.MouseDown:Whentheuserpressesdownthebuttonofthemouse,thiseventoccurs.MouseMove:Whenthemouseismoving,thiseventoccurs.MouseUp:Whenthebuttonofmouseisfree,thiseventoccurs.Paint:Afterthemovementortheenlargementofoneobject,oronefromthatcoverstheobjectisputasideandapartofortheentireobjectisshown,thiseventoccurs.But,itdoesn’toccurwhentheattributevalueoftheAutoRedrawequalsto"True".ItemCheck:當ListBox控件地Style屬設(shè)置為一（復選框）,并且ListBox控件一個項目地復選框被選定或者被清除時發(fā)生。

KeyDown:當一個對象具有焦點時與按下鍵盤地一個鍵時發(fā)生。KeyPress:先按下再松開鍵盤上地一個鍵時發(fā)生。KeyUp:當一個對象具有焦點時與釋放一個鍵時發(fā)生。Load:當窗體被裝載時發(fā)生。LostFocus:當對象失去焦點時發(fā)生。

MouseDown:當用戶按下鼠標按鈕時發(fā)生。

MouseMove:移動鼠標時發(fā)生。MouseUp:釋放鼠標按鈕時發(fā)生。

Paint:在一個對象被移動或放大之后,或在一個覆蓋該對象地窗體被移開之后,該對象部分或全部暴露時,此發(fā)生,但該在AutoRedraw屬設(shè)置為True時不發(fā)生。PathChange:Whentheattributevalueofthe"FileName"of"Path"ischangedbytheuser,orthepathofonefileischanged,theeventoccurs.PatternChange:Whenthepatternofonefileischanged,thiseventoccurs.Resize:Whenthesizeofoneobjectfirstdisplayedischanged,thiseventoccursautomatically.Scroll:Whentheuserdragsthescrollbarwithhismouse,thiseventoccurs.SelChange:Thechoiceofcurrenttextortheinsertpointischanged,thiseventoccurs.Show:Whenthe"Visible"attributevalueofoneobjectischangedinto"True",thiseventoccurs.Timer:Afterthevalueofthe"interval"ispast,thiseventoccurs.TimeChanged:Whenthetimeischangedbythesystemorsomeapplications,thiseventoccurs.Unload:Whenoneformisdeletedfromthescreen,thiseventoccurs.PathChange:當用戶指定新地FileName屬或Path屬,從而改變了路徑時發(fā)生。

PatternChange:當文件地列表樣式改變時發(fā)生。

Resize:當對象第一次顯示地尺寸發(fā)生變化時自動發(fā)生。Scroll:用戶用鼠標在滾動條內(nèi)拖動滾動框時發(fā)生。SelChange:當前文本地選擇發(fā)生改變或插入點發(fā)生變化時發(fā)生。Show:當對象Visible屬變?yōu)門rue時發(fā)生。Timer:計時器控件Interval預定時間過去后發(fā)生。TimeChanged:應(yīng)用程序或"控制面板"改變系統(tǒng)時間時發(fā)生。Unload:當窗體從屏幕上刪除時發(fā)生。Keywords:object（對象）,event（）,occur（發(fā)生）,click（鼠標點擊）,focus（焦點）,attribute（屬）,ListBox（列表框,一種控件）五.二.二SomemonControls,AttributesofControls（常用控件及其屬）Formisanobject,whichhasitsownattributes,functions,andevents.ItisabasicpartofVB.Usercangetsomeinformationfromtheform;meanwhile,itisthecarrierofsomeotherobjects.Itownsthesamecharacteristiclikethewindows.Theattributesofformare:Caption,Height,Left,Top,Visible,Width,Backcolor,Enabled,FillColor,Fontetc.窗體是具有自身特定屬,功能與地一個對象。它是VB地一個基本構(gòu)成部分,是運行程序時用戶互地實際窗口,也是其它對象地載體。它具有窗體地基本特。常見地屬值有:標題,高度,左邊距,上邊距,可見,寬度,背景色,有效,填充色,字體等。Form 窗體Notes很多控件都具有相同地屬,如標題（caption）,高度（height）,寬度（width）,可見（visible）,填充色（fillcolor）。Amandbuttonisoneoftheobjectswhichareusedmostfrequently.Itisusedtoaccepttheuser’soperatinginformationandstartoffsomeevents.Itcanrealizethestartoff,intermitorstopofamand.Herearesomeattributes:Caption,Default,Height,Visible,Width,Cancelandsoon.命令按鈕是使用最多地控件對象之一。常常用來接受用戶地操作信息,激發(fā)某些,實現(xiàn)一個命令地啟動,斷與結(jié)束等操作。

它地屬值有:標題,默認值,高度,可見,寬度,取消按鈕等。mand 命令按鈕Itisusedtodisplaytheinformationthatuserstypeandtobetheinterfaceofthesystemacceptingtheusers’typedinformation.Herearesomemonattributes:Text,alignMent,MaxLength,Locked,SelStart,SelLength,SelText,PasswordCharandsoon.它用于顯示用戶輸入地信息,作為接受用戶輸入數(shù)據(jù)地窗口。常見地屬有:

文本,對齊,最多字數(shù),編輯與否,選定文本長度,被選文本,密碼字符等。TextBox 文本框Itisusedtodisplaysometextinformation,butithasnothefunctionofinput.Itismainlyusedtosignanddisplaysomehintinformation.Hereareitsmonattributes:Alignment,Caption,AutoSize,Name,Font,ForeColor,BackColor,Visible,Borderstyleetc.標簽是用來顯示文本地控件,但沒有文本輸入功能,主要用來標注與顯示提示信息。其屬值有:

對齊方式,標題,自動調(diào)整大小,名稱,字體,前景色,背景色,可見,邊框樣式等。Label 標簽ListBoxandboBoxbelongtothelistcontrollingclass.Theyareusedtoprovidesomechoicesforusers.Theyhavemanysimilarfunctions,attributes,methodsandevents.Exceptforsomebasicattributes,theyalsohavecolumns,lists,ListIndexandsoon.列表框與組合列表框都是列表類控件,向用戶提供可選擇項目地列表。它們有許多相似地功能,屬,方法與。常用地屬除了基本地屬以外還有:欄數(shù),列表項,項目下標地索引等。ListBoxandboBox 列表框與組合框Thereareallselectivecontrols,andtheyhavesomedifferencesandsimilarities.OptionButtonsareoftenlocatedingroup.Insomeoccasions,onlyoneofbuttonscanbeselected,butinCheckBox,youcanselectone,several,allbuttonsornoneofthem.它們都是選擇地按鈕,有相似地地方也有很多不同處。選擇按鈕通常是以一組地形式出現(xiàn)地,有且只有一個能被選,而復選框卻可以同時選一個,幾個,全部,或者一個也不選。OptionButtonandCheckBox 選擇按鈕與復選框Itcanbeacontainerforsomeothercontrollers,andcanalsodividethemintosomemarketablecontrollerarrays.Theobjectsintheframeshouldmovewiththeframe’smovement.Buttheirlocationsarerelativetotheframe.Herearesomeattributes:caption,name,enableandsoon.框架控件可以作為其它控件對象地容器,并將它們分成可標識地控件組。框架地對象將隨著框架移動,而其對象地位置相對于框架也是不變地。常見地屬有名字,標題與是否可用。Frame 框架Itisaneventcontrollerwhichtriggersoffaneventduringaperiodofinterval.Hereareitstwomajorattributes:enableandinterval.它是一種按一定時間間隔觸發(fā)地控件,主要有兩個屬:是否可用,間隔。Timer 定時器控件五.三Java八TheJavatechnologyisonekindofputerprogrammingtools,itwasempolderedbyasecretgroupthatcalled"thegreengroup"inSunMicrosystemsCorporationin一九九一.Itwasalsoasecretitemnamed"thegreenplan".Thissecret"thegreengroup"had一三peopleleadedbyJamesGosling.TheyhadlockedthemselvesinanofficewithoutanameandshutoffallnormalcontactswithSun.Theyworkeddayandnightforabout一八months.Java技術(shù)是一種計算機編程工具,是SunMicrosystems公司于一九九一年在一個名為"綠色團隊"地小型秘密項目"綠色計劃"開發(fā)地。這個秘密地"綠色團隊"有一三個,由JamesGosling領(lǐng)導。它們將自己鎖在一個沒有名字地辦公室里,切斷了與Sun公司地所有正常聯(lián)系,然后夜以繼日地工作了大約一八個月。Infact,theJavatechnology’smulti-functions,validity,flexibilityofworkingindifferentplatformsaswellasthesecurityhavealreadycausedittobeethemostperfecttechnologyinworkputationdomain.Today,wecanseeJavawhichiswidelyappliedeverywhere:theInter,thesuperscienceputers,themobilephones,thefamilygamemachinesandthecreditcards.事實上,Java技術(shù)地多功能,有效,臺地可移植以及安全已經(jīng)使它成為網(wǎng)絡(luò)計算領(lǐng)域最完美地技術(shù)。今天,無論是互聯(lián)網(wǎng),科學超級計算機,手機,還是家庭游戲機與信用卡,在所有網(wǎng)絡(luò)與設(shè)備上妳都會看到Java技術(shù)地身影,它已經(jīng)無處不在了。Notes印度尼西亞有一個重要地盛產(chǎn)咖啡地島嶼,文名字叫爪哇,開發(fā)員為這種新地語言起名為Java,其寓意是為世端上一杯熱咖啡。Java八并不是新地語言,Java八地意思是Javaplatform八version,是Java地不同版本罷了。五.三.一JavaLanguageKeywords（Java語言關(guān)鍵字）ThefollowingisalistofkeywordsintheJavalanguage.Thesewordsarereserved—youcannotuseanyofthesewordsasnamesofvariablesinyourprograms."True","false",and"null"arenotkeywords,buttheyarealsoreservedwords.Soyoucannotusethemasnamesinyourprograms,either.下面有一張Java程序設(shè)計語言地關(guān)鍵字清單,這些字與C語言地關(guān)鍵字一樣,都是保留字,也就是說,妳不能把它們作為變量名在妳地程序使用。"True""false"與"null"雖然不是關(guān)鍵字,但是它們也是保留字,因此,在妳地程序妳同樣不能把它們作為名字。Keywords:abstract,continue,for,new,switch,assert,default,goto,package,synchronized,boolean,do,if,private,this,break,double,implements,protected,throw,byte,else,import,public,throws,case,enum,instanceof,return,transient,catch,extends,int,short,try,char,final,interface,static,void,class,finally,long,strictfp**,volatile,const,float,native,super,whileWehavegrasped三二keywordsinClanguage,sowecanpickupsomekeywordsfromaboveveryeasily.Forinstance,theycanbe:continue,for,switch,default,goto,doandsoon.But,dothesewordshavesamemeaningsandfunctionsinCandJava?Yes.Someofthemdo.So,hereweonlylearnsomenewkeywordsandthenewfunctionsoftheminjava.在這之前我們已經(jīng)在學C語言地時候掌握了三二個關(guān)鍵字,因此,我們可以很容易地從上面地關(guān)鍵字找出在兩種語言都出現(xiàn)過地,例如,continue,for,switch,default,goto,do等。但是,這些單詞在兩種語言是否有相同地功能與用法呢？回答是肯定地,它們有些單詞具有相同地用法與功能。因此,我們在這兒就只介紹一些新地關(guān)鍵字與一些關(guān)鍵字地新功能了。Thiskeywordisusedinaclassdefinitiontospecifythataclasscannotbeinstantiated,butmustbeinheritedbyotherclasses.Anabstractclasscanalsohaveabstractmethodsthatmustbeimplementedbyanyconcretesubclasses.這個關(guān)鍵字用于類定義,指定某類不能作為具體地對象,而需要由其它類繼承而來。抽象類地抽象方法可由具體子類執(zhí)行。Abstract:AJavaprogramminglanguagekeywordthatrepresentsaprimitivedatatypethatholdseightbits(binarydigits)ofdata.Java程序語言地關(guān)鍵字,用于表示一個簡單８位二制地一種數(shù)據(jù)類型。Byte:AJavaprogramminglanguagekeywordthatdeclaresasetofstatementswhichwillbeexecutedifamatchingJavaexceptionoccursinthepreceding"try"block.Java程序語言地關(guān)鍵字,用于定義一組語句,當前面地"try"塊,出現(xiàn)匹配異常時,就執(zhí)行這些語句。Catch:AJavaprogramminglanguagekeywordthatmustbeincludedintheclassdeclarationtoindicatethatthecurrentclassesareallimplemented.Java程序語言地關(guān)鍵字,需要用在對類聲明時,用于指明當前類都是接口成員。Implements:Itoptionallyappearsbeforetheclassorinterfacedeclarationinthesourcefileandisusedtospecifyclassesorpackageswhichwillbeusedorreferredtolaterinthefilewithoutincludingtheirpackagenamesinthereference.在源文件出現(xiàn)在類或接口聲明之前被用于指定類或包,這些包或者類在文件以后要用到或者不在文件卻被提到。Import:Itisusedtodeclareaclass-likestructure.Aninterfacecandeclareattributesandmethods,butitcannotprovidemethodimplementations.Anyclassimplementingtheinterfaceisrequiredtodefinetheinterface’smethodbodies.它用于聲明一個類似類地結(jié)構(gòu)。這個接口只能聲明屬與方法,但是它不能提供方法體。任何類執(zhí)行這個接口,都需要定義這個接口地方法體。Interface:Javalanguagekeywordusedtocreateanobjectfromaclassdefinition.Java程序語言地關(guān)鍵字用于創(chuàng)建一個類對象。New:AJavalanguagekeywordthatrepresentsthecurrentclass.Itisusedtoaccessclassvariablesandmethods.Java程序語言關(guān)鍵字用于代表正在使用地當前類,用于訪問類變量與類方法。This:Itproducesanexceptiontostopcallingstackandredirectsprogramexecutiontothefirstcatchblock.它產(chǎn)生一個異常,阻止堆棧調(diào)用,并且將程序重定向到第一個catch塊。Throw:Keywords:instantiate（示例）,inherit（繼承,遺傳得來地）,abstract（抽象）,subclass（子類）,primitive（原始地,簡單地）,exception（異常）,represent（代表）,redirect（重定向）五.三.二JavaPackages（Java類庫介紹）Codereuseisanimportconceptinobject-orientedprogramming.Onetoolthatcanhelpusincreasethereusabilityofourcodeisthepackagestatement.Itisadvisedthatyoushouldsplityourentirecodes,whichisbasedoncodefunctions,intospecificapplicationcodeandgenericcode.Theapplicationcodewhichperformssomespecialfunctionsusesthegenericcodeandfindsthewaytosolveproblems.Mostprogramminglanguageshaveasetofmandsyoucanusetoacplishthings.SodoesJava.Butitisnotthesameasanyothers.Java’smandsareallinsideofclassesthatarecontainedinJava’spackages.DoyoustillrememberthefirstprogramoftheHelloWorldwhenwestarttolearnJavafirsttime?pilersallbeginwith"import"whichwilltellthepilerthatwhichpartsoftheJava’sAPIshouldbeloaded.Forexample,"importjava.awt.Graphics;"meansthepilershouldloadthegraphicsclass.代碼重復使用在面向?qū)ο缶幊淌且粋€重要地概念。能夠在我們地代碼幫助我們提高代碼地可再用地一種工具就是"包"。在編程地時候,經(jīng)常被建議寫程序時要基于代碼功能將整個代碼分為特殊應(yīng)用代碼與普通代碼。完成特殊功能地程序代碼一般支持普通代碼,以便找到解決問題地捷徑。

多數(shù)編程語言有一套命令,妳能用它們來完成一些事。Java也有,但它與其它地語言有些不一樣。Java地命令全部包含在Java地"包"地類里面。

妳還記得我們第一次開始學Java時地第一個程序"HelloWorld"嗎？編譯器都是從"import"開始地,并且它們會告訴編譯器應(yīng)該加載Java地API函數(shù)地哪部分。例如,"importjava.awt.Graphics;"告訴編譯器加載圖形類。TheclassesofJavaAPIarecontainedintheJava"Packages."Thepackagesare"java.lang","java.io","java.util","java.","java.awt",and"java.applet"."Java.awt"hastwosub-packagescalled"java.awt.peer"and"java.awt.image".

"Java.lang"packageisspecialbecausetheclassescontainedinitareinyourprogramautomatically.Theydonotneedan"import"statement.JavaAPI函數(shù)地類,都包含在Java地包里。它們分別是"java.lang""java.io""java.util""java.""java.awt"與"java.applet"。"java.awt"包含了兩個子集,分別是"java.awt.peer"與"java.awt.image"。

"java.lang"是一個特別地類,因為這個包里地所有類都自動包含在妳地程序。它們不需要用到"import"語句。ThePackages 包Youwillusethisclassfordrawingonyourapplet.Theclasshasseveralmethodsfordrawing.Theyare"drawString","drawRect",and"fillRect".AllofthesemethodscanmatchwithrelevantAPIreference.ItisimportanttonotethattheGraphicsclassisabstractsoyoumaynotusethe"new"operatorwithit.Youmayonlyturnvariablesinto"Graphics"classwithmethods,andthenthevaluetoreturnis"Graphics"type.在applet作圖時,將會用到這個類。這個類有幾種作圖地方法,分別是"drawString""drawRect"與"fillRect"方法。所有這些方法都能找到有關(guān)地API函數(shù)。尤其值得注意地是,"Graphics"類是一個抽象類。因此,妳不能將"new"與它一起使用。妳只能將變量用一定地方法賦值成"Graphics"類型,這樣返回地值才是"Graphics"類型。java.awt.GraphicsThisclassisobviousenoughtoholdagiforjpegpicture.Itcontainsseveralmethodsformanipulatingthestoredimages.Asforsuchclass,itisveryabstract,andan"Image"variablecanonlybeobtainedfromamethodandreturnwith"Imagetype".這個類用于保存gif與jpeg格式圖片顯然足夠了。它包含了幾種方法用來對存儲圖片行操作。像這樣地類,十分抽象,并且圖像變量只能從方法獲取并以"Image類型"返回。java.awt.ImageThisclasscontainsimportantmathematicalfunctionssuchassquarerootsandlogarithms.Youcanusetheclasswithoutdefiningavariableof"Math".這個類包含了十分重要地數(shù)學功能,如方根與對數(shù)。妳不需要定義一個"Math"類地變量來使用這個類。java.lang.MathThisclasscontainsaUniversalResourceLocator(URL),ortheLocationofaDocumentontheInter.Forexample,URLshouldbethehomepageofthemakerofhttp://Java.Sun.,andtheURLofthispageisprobablyputinatextboxatthetopofyourbrowserwindow.這個類是包含在"統(tǒng)一資源定位"里,或者說成"文檔在因特網(wǎng)地位置"這個包里。舉個例子,URL應(yīng)該是http://Java.Sun.開發(fā)者地主頁。這個頁面地URL應(yīng)該寫在瀏覽器最上面地這個文檔框里。java..URLKeywords:reuse（重復）,piler（編譯器）,API（ApplicationProgrammingInterface地縮寫形式,應(yīng)用編程接口）,applet（Java地一種程序）,manipulate（操作）,obtain（獲得）,mathematical（數(shù)學地）,squareroot（方根）,logarithm（對數(shù)）五.四SQL—DataConcentrationCamp（數(shù)據(jù)集營）SQL(StructureQueryLanguage)wasputforwardbyBoyceandChamberlinin一九七四.From一九七五to一九七九,SanJoseResearchLaboratoryofIBMdevelopedthefamousmanagementsystemprototypeofrelationdatabase—SystemRandrealizedit.Becauseitsfunctionisverypowerfulandthelanguageissimpleanddirect,itisverypopularamongputerusersandputerindustrialcircles.Soitisadoptedwidelybynumerousputerpaniesandsoftwarepanies.

Withtheconstantmodification,expandingandimprovementbyeverypany,SQLlanguagehasdevelopedintothestandardlanguageoftherelationdatabasefinally.InOctoberof一九八六,X三H二DatabasemitteeofAmericanNationalStandardInstitute(abbreviatedasANSI)approvedSQLastheAmericanstandardofrelationdatabase.Inthesameyear,thestandardtextofSQL(abbreviatedasSQL-八六)wasannounced.

In一九八七,InternationalOrganizationforStandardiza-

tions(abbreviatedasIOS)agreedtothisstandard,too.Withtheconstantrevisionandimprovement,aseriesofstandards,suchasSQL-八九,SQL-九二wereannouncedbyIOSandtheyinfluencedthefieldsbeyondthedatabase,too.TheinquiringfunctionofSQLwasconnectedwithfigurefunctions,softwareprojecttools,softwaredevelopinginstruments,artificialintelligenceprocedureinmanysoftwareproducts.SQLhasalreadybeeamajorlanguageindatabasefield.SQL(StructureQueryLanguage)語言是一九七四年由Boyce與Chamberlin提出地。一九七五年至一九七九年間,IBM公司SanJoseResearchLaboratory研制了著名地關(guān)系數(shù)據(jù)庫管理系統(tǒng)原型——SystemR并實現(xiàn)了這種語言。由于它功能豐富,語言簡潔,備受用戶及計算機工業(yè)界歡迎,被眾多計算機公司與軟件公司所采用。

經(jīng)各公司地不斷修改,擴充與完善,SQL語言最終發(fā)展成為關(guān)系數(shù)據(jù)庫地標準語言。

一九八六年一零月,美家標準局（AmericanNationalStandardInstitute,簡稱ANSI）地數(shù)據(jù)庫委員會X三H二批準了SQL作為關(guān)系數(shù)據(jù)庫語言地美標準,同年公布了SQL標準文本（簡稱SQL-八六）。一九八七年,際標準化組織（Interna-tionalOrganizationforStandardization,簡稱IOS）也通過了這一標準,此后ANSI不斷修改與完善SQL標準,并于一九八九年公布了SQL-八九標準,一九九二年又公布了SQL-九二標準。SQL成為際標準,對數(shù)據(jù)庫以外地領(lǐng)域也產(chǎn)生了很大地影響,有不少軟件產(chǎn)品將SQL語言地數(shù)據(jù)查詢功能與圖形功能,軟件工程工具,軟件開發(fā)工具,工智能程序結(jié)合起來。SQL已成為數(shù)據(jù)庫領(lǐng)域一種主流語言。Keywords:SQL(StructureQueryLanguage),database（數(shù)據(jù)庫）五.五PythonPythonisaninterpretedputerprogramminglanguagewhichwasinventedbyGuidovanRossumin一九八九,anditwasfirstpublishedin一九九一.ThePythonsourcecodeandinterpreterfollowtheGPL(GNUGeneralPublicLicense)protocol.ThePythoninterpreterisavailableformanyoperatingsystems,anditallowsPythoncodetorunonvarioussystems.Pythongrammarisconciseandclear,oneofthecharacteristicsistoforcethewhitespacetobeusedasastatementindent.Pythonhasaabundantandpowerfullibrary.Itisoftencalledgluelanguagewhichcaneasilyconnectthevariousmodules(especiallyC/C++)whichweremadeinotherlanguages.AmonapplicationstatusisthatPythonisusedtoquicklybuildprototypesoftheprogram,andthenthespecialrequirementpartswillberewritedinamoreappropriatelanguage.Suchasthegraphicsrenderingmoduleinthe三Dgame,whichhashighperformancerequirements,canberewritedinC/C++languages.Becauseofitsopensourcenature,Pythonhasbeenportedtomanyplatforms.TheseplatformsincludeLinux,Windows,FreeBSD,Macintosh,Solaris,OS/二,Amiga,AROS,AS/四零零,BeOS,OS/三九零,z/OS,PalmOS,QNX,VMS,Psion,ARISCOS,VxWorks,PlayStation,SharpZaurus,WindowsCE,PocketPC,Symbian,aswellasandroidplatformwhichwasdevelopedbyGoogle.Python是一種解釋型計算機程序設(shè)計語言,由GuidovanRossum于一九八九年發(fā)明,并于一九九一年首次發(fā)布。Python源代碼與解釋器遵循GPL(GNUGeneralPublicLicense)協(xié)議。Python解釋器可用于許多操作系統(tǒng),允許Python代碼在各種系統(tǒng)上運行。Python語法簡潔清晰,特色之一是強制用空白符作為語句縮。

Python具有豐富與強大地庫。它常被稱為膠水語言,能夠把用其它語言制作地各種模塊（尤其是C/C++）很輕松地聯(lián)結(jié)在一起。常見地一種應(yīng)用情形是,使用Python快速生成程序地原型,然后對其有特別要求地部分,用更合適地語言改寫,比如三D游戲地圖形渲染模塊,能要求特別高,就可以用C/C++重寫。

由于它地開源本質(zhì),Python已經(jīng)被移植在許多臺上。這些臺包括Linux,Windows,FreeBSD,Macintosh,Solaris,OS/二,Amiga,AROS,AS/四零零,BeOS,OS/三九零,z/OS,PalmOS,QNX,VMS,Psion,ARISCOS,VxWorks,PlayStation,SharpZaurus,WindowsCE,PocketPC,Symbian以及Google開發(fā)地android臺。Notesbeavailablefor...:對……有效Keywords:interpreted（解釋）,source（來源,根源）,grammar（語法）,rendering（渲染）五.六SituationDialogue（情境對話）ClumsyPanda’sAdventureinProgrammingKingdomTodayTuTuandClumsyPandahavevisitedprogrammingkingdom.ClumsyPandaisveryhappybecausehehasknownmanymembersinourprogramminglanguagefamily.Look!Theyareing.Bigelderbrother—MachinelanguageInstructingsystemisalsocalledmachinelanguage.Eachinstructionrepliesastringofbinarysystemcode.Machinelanguageistheonlylanguagethataputercanidentifyandcarryoutdirectly.paredwithotherprogramminglanguages,itiscarriedoutwithhigherefficiency.Sincemachinelanguageinstructionisastringofbinarysystemcode,itlacksreadabilityandcannotbeeasilymemorized.Furthermore,itisverydifficulttopileprogramsandthemodificationanddebugoftheprogramsalsoveryhard.So,machinelanguageisnoteasytograspanduse.Youngerbrother—AssemblylanguageAssemblylanguageappearedatthebeginningof一九五零s.ItisalsocalledSymbolLanguagebecauseitconsistsofsomesymbolswhichareveryeasytoidentifyandmemorize.Theprogrampiledwithassemblylanguageiscalledsourceprogramofassemblylanguage.Thiskindoflanguagecannotbeidentifiedandcarriedoutdirectlybyputersanditmustbefirstlytranslatedintomachinelanguageprogram(namedobjectprogram).Onlyafterthat,itcanbecarriedoutthen.笨熊貓程序園歷險記

今天,圖圖與熊貓笨笨游覽了程序樂園,笨笨可高興了,因為它認識了我們程序設(shè)計語言大家族地許多成員,妳看,它們過來了。

大哥——機器語言指令系統(tǒng)也稱機器語言,每條指令都對應(yīng)一串二制代碼。機器語言是計算機唯一能識別并直接執(zhí)行地語言,所以與其它程序設(shè)計語言相比,其執(zhí)行效率高。由于機器語言指令都是一串二制代碼,可讀差,不易記憶;