實驗二面向?qū)ο缶幊獭緦嶒災(zāi)康摹客ㄟ^編程和上機實驗理解Java語言是如何體現(xiàn)面向?qū)ο缶幊痰幕舅枷?，熟悉類的封裝方法以及如何創(chuàng)建類和對象，熟悉成員變量和成員方法的特性，熟悉類的繼承性和類的多態(tài)性的作用，熟悉包、接口的使用方法，掌握OPP方式進行程序設(shè)計的方法?！緦嶒炓蟆烤帉懗绦?qū)崿F(xiàn)類的定義和使用。編寫不同成員和不同成員方法修飾方法的程序編寫體現(xiàn)類的繼承性（成員變量、成員方法、成員變量隱藏）的程序和多態(tài)性（成員方法重載、構(gòu)造方法重載）的程序。編寫接口的定義和使用的程序編寫包的定義和使用的程序?！緦嶒瀮?nèi)容】1、類的定義和使用importjava.io.PrintStream;publicclassDate{privateintyear,month,day;publicDate(intyear,intmonth,intday){this.set(year,month,day);}publicvoidset(inty,intm,intd){this.year=y;this.month=((m>=1)&&(m<=12))?m:1;this.day=((d>=1)&&(d<=daysOfMonth()))?d:1;}publicstaticbooleanisLeapYear(intyear){returnyear%400==0||year%100!=0&&year%4==0;}publicStringtoString(){returnthis.day+"/"+this.month+"/"+this.year;}publicvoidtomorrow(){this.day++;if(day>this.daysOfMonth()){day=1;month++;if(month>12){month=1;year++;}}}publicstaticintdaysOfMonth(intyear,intmonth){switch(month){case1:case3:case5:case7:case8:case10:case12:return31;case4:case6:case9:case11:return30;case2:returnisLeapYear(year)?29:28;default:return0;}}publicintdaysOfMonth(){returndaysOfMonth(this.year,this.month);}publicstaticvoidmain(Stringargs[]){Datedate1=newDate(2014,11,13);System.out.println("今天是"+date1.toString());date1.tomorrow();System.out.println("明天是"+date1.toString());}}(2)publicclassTable{ Stringname; doubleweight; doublewidth; doublelength; doubleheight; publicTable(){ name="方桌1號"; weight=200; width=20; length=30; height=10; } publicdoubleArea(){ doublearea; area=width*height; returnarea; } publicvoidDisplay(){ System.out.println("桌子名稱:"+name+"\r\n重量："+weight+"\r\n寬："+width+"\r\n長："+length+"\r\n高："+height); } publicvoidChangWeight(intweight){ this.weight=weight; }}classtestTable{ publicstaticvoidmain(String[]args) { doublearea; Tabletable=newTable(); area=table.Area(); System.out.println("桌子的面積是："+area); table.ChangWeight(300); table.Display(); }}2、修飾符的使用classStaticDemo{ staticintx; inty; publicstaticintgetX(){ returnx; } publicstaticvoidsetX(intnewX){ x=newX; } publicintgetY(){ returny; } publicvoidsetY(intnewY){ y=newY; }}publicclassTestDemo{ publicstaticvoidmain(String[]args){ System.out.println("靜態(tài)變量x:"+StaticDemo.getX()); //System,out.println("實例變量y:"+StaticDemo.getY());//非法 StaticDemoa=newStaticDemo(); StaticDemob=newStaticDemo(); a.setX(1); a.setY(2); b.setX(3); b.setY(4); System.out.println("靜態(tài)變量a.x"+a.getX()); System.out.println("實例變量a.y"+a.getY()); System.out.println("靜態(tài)變量b.x"+b.getX()); System.out.println("實例變量b.y"+b.getY()); }}3、繼承和多態(tài)的作用classRodent{ publicvoidShout(){ System.out.println("跑"); }}classMouseextendsRodent{ publicvoidShout(){ System.out.println("吱吱"); }}classGerbilextendsRodent{ publicvoidShout(){ System.out.println("沙沙"); }}classHamsterextendsRodent{ publicvoidShout(){ System.out.println("大大"); }}publicclassTestRodent{ publicstaticvoidmain(String[]args){ Rodent[]r=newRodent[3]; r[0]=newMouse(); r[1]=newGerbil(); r[2]=newHamster(); r[0].Shout(); r[1].Shout(); r[2].Shout(); }}4、接口的定義和使用publicclassInterfaceTest{ publicstaticvoidmain(String[]args) { doublex; circley=newcircle(2); x=y.calculate_area(); System.out.println("面積為"+x); }}interfacecal_area//聲明一個接口{ doublePI=3.14; doublecalculate_area();}classcircleimplementscal_area//實現(xiàn)接口的一個類{ doubler; circle(doubler){ this.r=r; } publicdoublecalculate_area(){//接口方法的實現(xiàn) returnPI*r*r; }}5、包的定義和使用Test_YMD.javapackageMypackage;importjava.util.*;publicclassTest_YMD{ privateintyear,month,day; publicstaticvoidmain(String[]args){ } publicTest_YMD(inty,intm,intd){ year=y; month=(((m>=1)&(m<=12))?m:1); day=(((d>=1)&(d<=31))?d:1); } publicTest_YMD(){ this(0,0,0); } publicstaticintthisYear(){ returnCalendar.getInstance().get(Calendar.YEAR); } publicintyear(){ returnyear; } publicStringtoString(){ returnyear+"-"+month+"-"+day; }}YMD_2.javaimportMypackage.Test_YMD;publicclassYMD_2{ privateStringname; privateTest_YMDbirth; publicstaticvoidmain(String[]args) { YMD_2a=newYMD_2("張弛",1990,1,11); a.output(); } publicYMD_2(Stringn1,Test_YMDd1){ name=n1; birth=d1; } publicYMD_2(Stringn1,inty,intm,in