第八次實(shí)驗(yàn)報(bào)告

第八次實(shí)驗(yàn)實(shí)驗(yàn)1：中國(guó)人、北京人和美國(guó)人實(shí)驗(yàn)要求：編寫程序模擬中國(guó)人、美國(guó)人是人，北京人是中國(guó)人。除主類外，程序中還有4個(gè)類：People、ChinaPeople、AmericanPeople和BeijingPeople類。要求如下：People類有權(quán)限是protected的double型成員變量height和weight，以及publicvoidspeakHello()、publicvoid averageHeight()和publicvoidaverageWeight()方法。ChinaPeople類是People的子類，新增了publicvoidaverageHeight()和publicvoidaverageWeight()方法。AmericanPeople類是People的子類，新增方法publicvoidAmericanBoxing() 。要求AmericanPeople重寫父類的publicvoidspeakHello()、publicvoidaverageHeight()和publicvoidaverageWeight()方法。BeijingPeople類是ChinaPeople的子類，新增publicvoidbeijingOpera()方法。實(shí)驗(yàn)代碼：//People.javapublicclassPeople{protecteddoubleweight,height;publicvoidspeakHello(){System.out.println("yayayaya");}publicvoidaverageHeight(){height=173;System.out.println("averageheight:"+height);}publicvoidaverageWeight(){weight=70;System.out.println("averageweight:"+weight);}}//ChinaPeople.javapublicclassChinaPeopleextendsPeople{publicvoidspeakHello(){System.out.println("您好")；}publicvoidaverageHeight(){height=168.78；System.out.println("中國(guó)人的平均身髙:"+height+"厘米");}publicvoidaverageWeight(){weight=65;System.out.printin(”中國(guó)人的平均體重："+weight+"千克")；}publicvoidchinaGongfu(){System.out.println("坐如鐘，站如松，睡如弓")；}}//AmericanPeople.javapublicclassAmericanPeopleextendsPeople{publicvoidspeakHello(){System.out.println("Howdoyoudo")；}publicvoidaverageHeight(){height=176；System.out.println("American'saverageheight："+height+"厘米")；}publicvoidaverageWeight(){weight=75；System.out.println("American'saverageweight："+weight+"kg")；}publicvoidamericanBoxing(){System.out.println("直拳，勾拳，組合拳")；}}//BeijingPeople.javapublicclassBeijingPeopleextendsChinaPeople{publicvoidaverageHeight(){height=172.5；System.out.println(”北京人的平均身髙："+height+"厘米")；}publicvoidaverageWeight(){weight=70；System.out.printin(”北京人得平均體重："+weight+"千克")；}pubiicvoidbeijingOpera(){System.out.printin(”花臉、青衣、花旦和老生")；}}//Exampie.javapubiicciassExampie{pubiicstaticvoidmain(Stringarg[]){ChinaPeoplechinaPeople=newChinaPeople();AmericanPeopleamericanPeople=newAmericanPeople();BeijingPeoplebeijingPeople=newBeijingPeople();chinaPeople.speakHello();americanPeople.speakHello();beijingPeople.speakHello();chinaPeople.averageHeight();americanPeople.averageHeight();beijingPeople.averageHeight();chinaPeople.averageWeight();americanPeople.averageWeight();beijingPeople.averageWeight();chinaPeople.chinaGongfu();americanPeople.americanBoxing();beijingPeople.beijingOpera();beijingPeople.chinaGongfu();}}4.實(shí)驗(yàn)分析：方法重寫時(shí)要保證方法的名字、類型、參數(shù)的個(gè)數(shù)和類型同父類的某個(gè)方法完全想同。這樣，子類繼承的方法才能被隱藏。子類在重寫方法時(shí)，如果重寫的方法是static方法，static關(guān)鍵字必須保留；如果重寫的方法是實(shí)例方法，重寫時(shí)不可以用static修飾。如果子類可以繼承父類的方法，子類就有權(quán)利重寫這個(gè)方法，子類通過重寫父類的方法可以改變父類的具遺體行為。5.實(shí)驗(yàn)后的練習(xí)：People類中的publicvoidspeakHello()publicvoidaverageHeight()publicvoidaverageWeight()三個(gè)方法的方法體中的語句是否可以省略答：可以省略，因?yàn)槭÷院蠼Y(jié)果沒有變化實(shí)驗(yàn)2：銀行計(jì)算利息實(shí)驗(yàn)要求：假設(shè)銀行bank已經(jīng)有了按整年year計(jì)算利息的一般方法，其中year只能取正整數(shù)。比如,按整年計(jì)算的方法：DoublecomputerInternet(){Interest=year*0.35*saveMoney;Returninterest;}建設(shè)銀行constructionBank是bankde子類，準(zhǔn)備隱藏繼承的成員變量year，并重寫計(jì)算利息的方法，即自己聲明一個(gè)double型的year變量。要求construetionbank和bankofDalian類是bank類的子類，constructionbank和bankofdalian都使用super調(diào)用隱藏的按整年計(jì)算利息的方法。實(shí)驗(yàn)代碼：//Bank.javapublicclassBank{intsavedMoney;intyear;doubleinterest;doubleinterestRate=0.29;publicdoublecomputerInterest(){interest=year*interestRate*savedMoney;returninterest;}publicvoidsetInterestRate(doublerate){interestRate=rate;}}//ConstructionBank.javapublicclassConstructionBankextendsBank{doubleyear;publicdoublecomputerInterest(){super.year=(int)year;doubler=year-(int)year;intday=(int)(r*1000);doubleyearInterest=puterInterest();doubledayInterest=day*0.0001*savedMoney;interest=yearInterest+dayInterest;System.out.printf("%d元存在建設(shè)銀行％d年零％d天的利息：％f元\n",savedMoney,super.year,day,interest);returninterest;}}//BankOfDalian.javapublicclassBankOfDalianextendsBank{doubleyear;publicdoublecomputerInterest(){super.year=(int)year;doubler=year-(int)year;intday=(int)(r*1000);doubleyearInterest=puterInterest();doubledayInterest=day*0.00012*savedMoney;interest=yearInterest+dayInterest;System.out.printf("%d元存在大連銀行％d年零％d天的利息：％f元\n",savedMoney,super.year,day,interest);returninterest;}//SaveMoney.javapublicclassSaveMoney{publicstaticvoidmain(Stringargs[]){intamount=8000;ConstructionBankbank1=newConstructionBank();bank1.savedMoney=amount;bank1.year=8.236;bank1.setInterestRate(0.035);doubleinterest1=puterInterest();BankOfDalianbank2=newBankOfDalian();bank2.savedMoney=amount;bank2.year=8.236;bank2.setInterestRate(0.035);doubleinterest2=puterInterest();System.out.printf("兩個(gè)銀行利息相差％f元\n",interest2-interestl)；}}實(shí)驗(yàn)結(jié)果：山C:\PROGRA"1\IINOKS"1\JCKEAT"1\GE2001.exepQBB工存在建設(shè)銀抵E年勢(shì)盹天拘禾息：242取陰00胸元P000丸存在夭逹銀行8^^236天的未I、息：24t6.56&BQ0無P個(gè)4艮廳剎息相差3?.760086元Pressanj;kei?tocontinue■?■.實(shí)驗(yàn)分析：（1） 子類不繼承父類的構(gòu)造方法，因此子類在其構(gòu)造方法中需使用super來調(diào)用父類的構(gòu)造方法，并且super必須是子類構(gòu)造方法中的頭一條語句。（2） 當(dāng)super調(diào)用被隱藏的方法時(shí)，該方法中出現(xiàn)的成員變量是被子類隱藏的成員變量或繼承的成員變量。實(shí)驗(yàn)后的練習(xí)：參照建設(shè)銀行或大連銀行，在編寫一個(gè)商業(yè)銀行，讓程序輸出8000元存在商業(yè)銀行8年零236天的利息。//Bank.javapublicclassBank{intsavedMoney;intyear;doubleinterest;doubleinterestRate=0.29;publicdoublecomputerInterest(){interest=year*interestRate*savedMoney;returninterest;}publicvoidsetInterestRate(doublerate){interestRate=rate;}}//CommercialBankpublicclassCommercialBankextendsBank{doubleyear;publicdoublecomputerInterest(){super.year=(int)year;doubler=year-(int)year;intday=(int)(r*1000);doubleyearInterest=puterInterest();doubledayInterest=day*0.00012*savedMoney;interest=yearInterest+dayInterest;System.out.printf("%d元存在商業(yè)銀行％d年零％d天的利息：％f元\n",savedMoney,super.year,day,interest);returninterest;}}//SaveMoney.javapublicclassSaveMoney{publicstaticvoidmain(Stringargs[]){intamount=8000;CommercialBankbank=newCommercialBank();bank.savedMoney=amount;bank.year=8.236;bank.setInterestRate(0.035);doubleinterest=puterInterest();}

22C:\PROGEL4"1\IINOKS"1\JCREAT"1\GE2001.ejluBB$000兀存在商業(yè)銀行8年零2并天：2466.5600007EPi*essanjkeytocnmlzinuE 』實(shí)驗(yàn)3：公司支出的總薪水實(shí)驗(yàn)要求：要求有一個(gè)abstract類，類名為Employee。Employee的子類有YearWorker、MonthWorker、WeekWorker。YearWorker對(duì)象按年領(lǐng)取薪水，MonthWorker按月領(lǐng)取薪水、WeekWorker按周領(lǐng)取的薪水。Employee類有一個(gè)abstract方法：publicabstractearnings();子類必須重寫父類的earings()方法，給出各自領(lǐng)取報(bào)酬的具體方式。有一個(gè)Company類，該類用Employee對(duì)象數(shù)組作為成員，Employee對(duì)象數(shù)組的單元可以是YearWorker對(duì)象的上轉(zhuǎn)型對(duì)象、MonthWorker獨(dú)享的上轉(zhuǎn)型獨(dú)享或weekworker對(duì)象的上轉(zhuǎn)型獨(dú)享。程序能輸出Company對(duì)象一年需要支付的薪水總額。實(shí)驗(yàn)代碼：abstractclassEmployee{publicabstractdoubleearnings();}classYearWorkerextendsEmployee{publicdoubleearnings(){return12000;}}classMonthWorkerextendsEmployee{publicdoubleearnings(){return12*2300;}classWeekWorkerextendsEmployee{publicdoubleearnings(){return52*780;}}classCompany{Employee[]employee;doublesalaries=0;Company(Employee[]employee){this.employee=employee;}publicdoublesalariesPay(){salaries=0;for(inti=0;i<employee.length;i++){salaries=salaries+employee[i].earnings();}returnsalaries;}}publicclassCompanySalary{publicstaticvoidmain(Stringargs[]){Employee[]employee=newEmployee[29];for(int