第6章类和对象的扩展

6classHuman{Stringname;intage;Human(Stringname,intage){}voidwalk()}}classChildextendsHuman{StringschoolName;Child(Stringname,intage,Stringschool){}void}classHuman{Stringname;intage;Human(Stringname,intage){}voidwalk()}}classChildextendsHuman{StringschoolName;Child(Stringname,intage,Stringschool){}void}void}}publicclasspublicstaticvoidmain(String[]args){Humanh=newHuman(" Childc=newChild(" }}6.2案例分析：VIP////Cust.javaclassCust{Stringname;intID;StringPWD;intmoney;Cust(Stringname,intID,intmoney,StringPWD){}voidgetMoney()intm=Integer.parseInt(KB.scan());if(m>=money){}}booleangetMoney(intm){if(m>=money){return}returntrue;}}voidintm=Integer.parseInt(KB.scan());}voidsaveMoney(intm){}voidchangePWD(){ Stringp=KB.scan();}voidsearch(){}booleancheckPWD(){ for(inti=0;i<3;i++){Stringif(p.equals(this.PWD)){returntrue;} }}return}voidif }booleanflag=true;while(flag){intcmd=Integer.parseInt(KB.scan());switch(cmd){case1:getMoney();break;case2:saveMoney();break;case3:search();break;case4:changePWD();break;case5:flag=false;break;}}}}//classVIPCustextendsVIPCust(Stringname,intID,intmoney,StringPWD){}voidgetMoney()intm=Integer.parseInt(KB.scan());if(m-3000>=money){}}booleangetMoney(intm){if(m-3000>=money){return}returntrue;}}}//KB.javaimportjava.io.*;classKB{publicstaticStringscan(){Stringstr="";tryBufferedReaderbuf=newBufferedReader(newInputStreamReader(System.in));}catchcatch(Exceptione)}return}}//Demo.javaclassDemopublicstaticvoidmain(String[]args){Custc=newCust("Tom",111,1000,"111");VIPCustv=newVIPCust("Jerry",1111,1000,"1111");while(true){intid=Integer.parseInt(KB.scan());if(id==c.ID){}elseif(id==v.ID){}Stringstr=KB.scan();if(str.equals("Y")||str.equals("y")){}}}}classvoidspeak(){}l}classdogextendsm voidspeak(){}}classcatextendsm voidspeak(){}classvoidspeak(){}l}classdogextendsm voidspeak(){}}classcatextendsm voidspeak(){}}}publicclassdemopublicstaticvoidmain(String[]args){ lm;m=newm m=newdog();m=newcat();}}classclassvoidaMethod(){System.out.println("Amethod");}}classBextendsA{voidbMethod1(){System.out.println("B}voidbMethod2(){System.out.println("Bmethod2");}}publicclasspublicstaticvoidmain(String[]args)Aa1newB向Bb1=(B)a1;调用父类调用父类A方调用B调用BAa2=newBb2=(B)a2;//向 }}} privateintid;//IDprivateStringusername; privateStringpassword; voidprocScore();//publicintgetId(){returnid;}publicvoidsetId(intid){this.id=id;}publicStringgetUsername(){returnusername;}publicvoid privateintid;//IDprivateStringusername; privateStringpassword; voidprocScore();//publicintgetId(){returnid;}publicvoidsetId(intid){this.id=id;}publicStringgetUsername(){returnusername;}publicvoidsetUsername(Stringusername){this.username=username;}publicStringgetPassword(){returnpassword;}publicvoidsetPassword(Stringpassword){this.password=password;}}classManagerextends voidprocScore(){}}classStudentextends voidprocScore(){}}classTeacherextends voidprocScore(){}}}publicclasspublicstaticvoidmain(String[]args){Teachert=newTeacher();Students=newStudent();Managerm=newManager();}}classOuter{//外部类OuterprivateStringoutStr;Outer(Strings)outStr=}publicvoidoutMethod(){//外部类中 classOuter{//外部类OuterprivateStringoutStr;Outer(Strings)outStr=}publicvoidoutMethod(){//外部类中 Innerin=newInner();//创建内部类实例 }classInnerpublicStringinStr="内部类的变量";publicvoidinMethod(){ }}}publicclasspublicstaticvoidmain(Stringargs){Outero=newOuter("外部类的变量");Outer.Inneri=o.newInner(); }}packagea;publicclassA{}packagea.b;publicclassB{}importa.*;publicclassTest{publicstaticvoidmain(Stringargs){Bb=newB();//语法错误，B类未引入}} //Cust.javapackage//Cust.javapackageCust;importpublicclassCust{Stringname;intID;StringPWD;intmoney;publicCust(Stringname,intID,intmoney,StringPWD){}publicintgetID(){returnID;}voidgetMoney()intm=Integer.parseInt(KB.scan());if(m>=money){}}booleangetMoney(intm){if(m>=money){return}returntrue;}}voidintm=Integer.parseInt(KB.scan());}voidsaveMoney(intm){}voidchangePWD(){ Stringp=KB.scan();}voidsearch(){}booleancheckPWD(){ for(inti=0;i<3;i++){Stringif(p.equals(this.PWD)){returntrue;} }}return}publicvoidrun(Custst[]){if }booleanflag=true;while(flag){intcmd=Integer.parseInt(KB.scan());switch(cmd){case1:getMoney();break;case2:saveMoney();break;case3:search();break;case4:changePWD();break;case5:flag=false;break;}}}}//VIPCust.javapackageCust;importKB.KB;publicclassVIPCustextendspublicVIPCust(Stringname,intID,intmoney,StringPWD){}voidintm=Integer.parseInt(KB.scan());if(m-3000>=money){}}publicbooleangetMoney(intm){if(m-3000>=money){return}returntrue;}}voidzhuanzhang(Custst[]){intm=Integer.parseInt(KB.scan());for(inti=0;i<st.length;i++){if(m==st[i].ID){intn=Integer.parseInt(KB.scan());if(n>=0){if(this.getMoney(n)){}}if(st[i].checkPWD()==true){}} }}}}}publicvoidrun(Custst[]){if }booleanflag=true;while(flag){intcmd=Integer.parseInt(KB.scan());switch(cmd){case1:getMoney();break;case2:saveMoney();break;case3:search();break;case4:changePWD();break;case5:zhuanzhang(st);break;case6:flag=false;break;}}}}//KB.javapackageKB;importjava.io.*;publicclasspublicstaticStringscan(){Stringstr="";BufferedReaderbuf=newBufferedReader(new}catch(Exceptione)}return}}//Demo.javaimportCust.Cust;importCust.VIPCust;importKB.KB;classpublicstaticvoidmain(String[]args){Custst[]=newCust[8];st[0]=newst[0]=newst[1]=newst[2]=newst[3]=newCust("Linda",444,4000,"444");st[4]=newVIPCust("Tom",1111,1000,"1111");st[5]=newVIPCust("Jerry",2222,2000,"2222");st[6]=newVIPCust("Mary",3333,3000,"3333");st[7]=newVIPCust("Linda",4444,4000,"4444");whileintid=Integer.parseInt(KB.scan());for(inti=0;i<st.length;i++){if}}Stringstr=KB.scan();if(str.equals("N")||str.equals("n")){}}}}interface}interface}voidspeak();voideat();voidclassDogimplementsIM publicvoidspeak(){}publicvoideat(){}publicvoidsleep(){}}classCatimplementsIM classCatimplementsIM publicvoidspeak(){}publicvoideat(){}publicvoidsleep(){}}publicclassDemopublicstaticvoidmain(Stringargs){Dogd=newDog();Catc=newCat();}}interfaceIMotocar{voidinterfaceIMotocar{void}interfaceICarextendsIMotocar{voidmethod2();}interfaceITruckextendsIMotocar{voidmethod3();}interfaceIStation_waggonextendsICar,ITruck继承多个接口voidmethod4();}classMycarimplementsIStation_waggon{publicvoidmethod1(){}publicvoidmethod2(){}publicvoidmethod3(){}publicvoidmethod4(){}}publicclasspublicstaticvoidmain(String[]args){Mycarm=newMycar();}}publicpublicclassExceptionDemopublicstaticvoidmain(String[]args){Strings=null;intlen=}}publicpublicclasspublicstaticvoidmain(String[]args){intintfor(i=0;i<=10;i++){sum=sum+a[i];}} ceptione){}}}}}public