classsuper{2.publicfloatgetNum(){return3.0f;}3.}4.5.publicclassSubextendsSuper{6.7.}Whichmethod,placedatline6,willcauseacompilererror?() A.PublicfloatgetNum（）{return4.0f；}B.PublicvoidgetNum（）{}C.PublicvoidgetNum（doubled）{}D.PublicdoublegetNum（floatd）{retrun4.0f；}
classsuper{2.publicfloatgetNum(){return3.0f;}3.}4.5.publicclassSubextendsSuper{6.7.}Whichmethod,placedatline6,willcauseacompilererror?()
A.PublicfloatgetNum（）{return4.0f；}
B.PublicvoidgetNum（）{}
C.PublicvoidgetNum（doubled）{}
D.PublicdoublegetNum（floatd）{retrun4.0f；}
相关考题：
classsuper{publicintgetLength（）{return4；}}publicclassSubextendsSuper{publiclonggetLength（）{return5；}publicstaticvoidmain（String[]args）{supersooper=newSuper（）；Subsub=newSub（）；System.out.printIn（sooper.getLength（）+，”+sub.getLength（）}；}Whatistheoutput？（）A.4，4B.4，5C.5，4D.5，5E.Thecodewillnotcompile.
classsuper（publicintI=0；publicsuper（stringtext）（I=1））publicclasssubextendssuper（publicsub（stringtext）（i=2）publicstaticvoidmain（straingargs[]）（subsub=newsub（Hello”）；system.out.PrintIn（sub.i）；））Whatistheresult？（）A.Compilationwillfail.B.Compilationwillsucceedandtheprogramwillprint“0”C.Compilationwillsucceedandtheprogramwillprint“1”D.Compilationwillsucceedandtheprogramwillprint“2”
classSuper{publicinti=0；publicSuper（Stringtext）{i=1；}}publicclassSubextendsSuper{publicSub（Stringtext）{i=2；}publicstaticvoidmain（Stringargs[]）{Subsub=newSub（Hello”）；System.out.println（sub.i）；}}Whatistheresult？（）A.0B.1C.2D.Compilationfails.
classSuper{publicintgetLenght（）{return4；}}publicclassSubextendsSuper{publiclonggetLenght（）{return5；}publicstaticvoidmain（String[]args）{Supersooper=newSuper（）；Subsub=newSub（）；System.out.println（sooper.getLenght（）+“，”+sub.getLenght（））；}}Whatistheoutput？（）A.4，4B.4，5C.5，4D.5，5E.Compilationfails.
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.4，4B.4，5C.5，4D.5，5E.Compilationfails.
classSuper{2.publicfloatgetNum(){return3.0f;}3.}4.5.publicclassSubextendsSuper{6.7.}Whichmethod,placedatline6,causescompilationtofail?() A.publicvoidgetNum（）{}B.publicvoidgetNum（doubled）{}C.publicfloatgetNum（）{return4.0f；}D.publicdoublegetNum（floatd）{return4.0d；}
classsuper{publicfloatgetNum(){return3.0f;}}publicclassSubextendsSuper{}Whichmethod,placedatline6,willcauseacompilererror?() A.PublicfloatgetNum（）{return4.0f；}B.PublicvoidgetNum（）{}C.PublicvoidgetNum（doubled）{}D.PublicdoublegetNum（floatd）{retrun4.0f；}
将下列哪个代码（A，B，C，D）放入程序中标注的【代码】处将导致编译错误？ class A { public float getNum（) { return 3.0f; } } public class B extends A { 【代码】 }A．public float getNum(){return 4.0f;}B．public void getNum(){ }C．public void getNum(double d){ }D．public double getNum(float d){return 4.0d;}
将以下哪种方法插入到第6行是不合法的（） 。 1．public class Test1 { 2． public float aMethod（float a，float b） throws 3． IOException { } 4． } 5．public class Test2 extends Test1{ 6． 7．}A．float aMethod（float a，float b）{ }B．public int aMethod（int a，int b）throws Exception{ }C．public float aMethod（float p，float q）{ }D．public int aMethod（int a，int b）throws IOException{ }