classSuper{publicintgetLenght(){return4;}}publicclassSubextendsSuper{publiclonggetLenght(){return5;}publicstaticvoidmain(String[]args){Supersooper=newSuper();Subsub=newSub();System.out.println(sooper.getLenght()+“,”+sub.getLenght());}}Whatistheoutput?()
A.4,4
B.4,5
C.5,4
D.5,5
E.Compilationfails.
第1题:
A.PublicfloatgetNum(){return4.0f;}
B.PublicvoidgetNum(){}
C.PublicvoidgetNum(doubled){}
D.PublicdoublegetNum(floatd){retrun4.0f;}
第2题:
classSuper{publicIntegergetLenght(){returnnewInteger(4);}}publicclassSubextendsSuper{publicLongGetLenght(){returnnewLong(5);}publicstaticvoidmain(String[]args){Supersooper=newSuper();Subsub=newSub();System.out.println(sooper.getLenght().toString()+,”+sub.getLenght().toString());}}Whatistheoutput?()
A.4,4
B.4,5
C.5,4
D.5,5
E.Compilationfails.
第3题:
A.PublicfloatgetNum(){return4.0f;}
B.PublicvoidgetNum(){}
C.PublicvoidgetNum(doubled){}
D.PublicdoublegetNum(floatd){retrun4.0f;}
第4题:
classSuper{publicinti=0;publicSuper(Stringtext){i=1;}}publicclassSubextendsSuper{publicSub(Stringtext){i=2;}publicstaticvoidmain(Stringargs[]){Subsub=newSub(Hello”);System.out.println(sub.i);}}Whatistheresult?()
A.0
B.1
C.2
D.Compilationfails.
第5题:
A.publicvoidgetNum(){}
B.publicvoidgetNum(doubled){}
C.publicfloatgetNum(){return4.0f;}
D.publicdoublegetNum(floatd){return4.0d;}