class Animal{ Animal getOne(){return new Animal();}}   class Dog extends Animal{   //insert code here   }   class AnimalTest{   public static void main(String[] args){   Animal[] animal={ new Animal(), new Dog()};   for(Animal a:animal){   Animal x= a.getOne();   }   }   }   和代码:   3a.Dog getOne() { return new Dog();}   3b.Animal getOne() { return new Dog();}   第3行中插入的哪项编译且运行无异常?  A、3a行或3b行B、既非3a,也非3bC、3a行D、3b行

class Animal{ Animal getOne(){return new Animal();}}   class Dog extends Animal{   //insert code here   }   class AnimalTest{   public static void main(String[] args){   Animal[] animal={ new Animal(), new Dog()};   for(Animal a:animal){   Animal x= a.getOne();   }   }   }   和代码:   3a.Dog getOne() { return new Dog();}   3b.Animal getOne() { return new Dog();}   第3行中插入的哪项编译且运行无异常?  

  • A、3a行或3b行
  • B、既非3a,也非3b
  • C、3a行
  • D、3b行

相关考题:

有如下程序: include using namespaee std;class Animal{ public: virtual char*g 有如下程序:include<iostream>using namespaee std;c lass Animal{public:virtual char*getType( )const{return"Animal";}virtual char*getVoice( )const{return"Voice";}};class Dog:public Animal{public:char*getType( )const{return"Dog";}char*getVoice( )eonst{return"Woof";}};void type(AnimalA) {cout<<a.getType( );}void speak(Animal A) {eout<<a.getVoice( );}int main( ){Dog d;type(D) ;cout<<"speak";speak(D) ;cout return 0;}程序的输出结果是______。

下列程序片段中,能通过编译的是A.public abstract class Animal{ public void speak();}B.public abstract class Animal{ public void speak(){}}C.public class Animal{ public abstract void speak();}D.public abstract class Animal{ public abstract void speak(){}}

( 12 )有如下程序:#include iostreamusing namespace stdclass Animal{public:virtual char* getType () const { return "Animal" ; }virtual char* getVoice () const { return "Voice" ; }};Class Dog : public Animal {public:char* getType ( ) const {return "Dog" ; }char* getVoice ( ) const {return "Woof"}};void type ( Animal a ) {couta.getType ( ) ; }void speak ( Animal a ) {couta.getVoice ( ) ; }int main ( ) {Dog d; type ( d ) ; cout" speak" ; speak ( d ) ; coutendi;return 0;}运行时的输出结果是【 12 】 。

It can be inferred from the passage that all of the following are ways of producing new strains of influenza viruses EXCEPT______.A. two influenza viruses in the same animal recombiningB. animal viruses recombining with human virusesC. two animal viruses recombining in one animalD. two animal viruses recombining in a human

使用VC6打开考生文件夹下的工程test19_1,此工程包含一个源程序文件test19_1.cpp,但该程序运行有问题,请改正程序中的错误,使程序的输出结果如下:1:weight:5age:02:weight:7age:9源程序文件test19_1.cpp 清单如下:include <iostream.h>class animal{public:/**************** found *******************/friend void setvalue(animal,int);/**************** found *******************/void print()protected:int itsweight;int itsage;};void animal::print(){cout<<"weight:"<<itsweight<<end1;cout<<"age:"<<itsage<<end1;}void setvalue(animal ta,int tw){ta.itsweight=tw;ta.ihsage=0;}void setvalue(animal ta,int tw, int tn){ta.itsweight=tw;ta.itsage=tn;}void main(){/**************** found *******************/animal peppysetvalue(peppy,5);cout<<"1:"<<end1;peppy.print();setvalue(peppy,7,9);cout<<"2:"<<end1;peppy.print();}

有如下程序:ncludeiostreamusing namespace std;class Animal{public:virtual char*getType()const{return“Animal”;}virtual char*getVoice()const{return“Voice”;}};class Dog:public Animal{public:char*getType()const{rgturn“Dog”;}char*getVoice()const{retum“Woof”;}};void type(AnimalA){couta.getType();}void speak(AnimalA){couta.getVoice();}int main(){Dog d.type(D);tout“speak”;speak(D);coutendl;return 0;}运行时的输出结果是【 】

下面程序输出的结果为#include"iostream.h"class A{public:A( ){cout<<"CLASS A"<<endl;}~A( ){}};class B:public A{public:B( ){cout<<"CLASS B"<<endl;}~B( ){}};void main( ){A*p;p=new B;B *q;q=new B;}A.CLASS A CLASS BB.CLASS A CLASS B CLASS BC.CLASS A CLASS B CLASS A CLASS BD.CLASS A CLASS B CLASS B CLASS B

下列程序片段中,能通过编译的是( )。 A.public abstract class Animal{ public void speak;}S 下列程序片段中,能通过编译的是( )。A.public abstract class Animal{ public void speak;}B.public abstract class Animal{ public void speak{);}C.public class Animal{ pubilc abstract void speak;}D.public abstract class Animal{ pubile abstract void speak{};}

classCatextendsAnimal{}对于下述代码说法正确的是()A、Cat是Animal的子类B、Animal是Cat的子类C、Cat是Animal的超类D、Animal一定是抽象类

interface Animal {  void soundOff();  }  class Elephant implements Animal {  public void soundOff() {  System.out.println(“Trumpet”);  }  }  class Lion implements Animal {  public void soundOff() { System.out.println(“Roar”);  }  }  class Alpha1 {  static Animal get( String choice ) {  if ( choice.equalsIgnoreCase( “meat eater” )) {  return new Lion();  } else {  return new Elephant();  }  }  }  Which compiles?()  A、 new Animal().soundOff();B、 Elephant e = new Alpha1();C、 Lion 1 = Alpha.get(“meat eater”);D、 new Alpha1().get(“veggie”).soundOff();

Clone animal:克隆动物

11. class Animal { public String noise() { return “peep”; } }  12. class Dog extends Animal {  13. public String noise() { return “bark”; }  14. }  15. class Cat extends Animal {  16. public String noise() { return “meow”; }  17. }  .....  30. Animal animal = new Dog();  31. Cat cat = (Cat)animal;  32. System.out.printIn(cat.noise());  What is the result?() A、 peepB、 barkC、 meowD、 Compilation fails.E、 An exception is thrown at runtime.

Which two demonstrate an “is a” relationship?()   A、 public interface Person { }  public class Employee extends Person { }B、 public interface Shape { }  public class Employee extends Shape { }C、 public interface Color { }  public class Employee extends Color { }D、 public class Species { }  public class Animal (private Species species;)E、 interface Component { }  Class Container implements Component ( Private Component[ ]children;  )

多选题Given: 10. interface Jumper { public void jump(); } ...   20. class Animal {} ...   30. class Dog extends Animal {   31. Tail tail;   32. }   ...   40. class Beagle extends Dog implements Jumper{   41. public void jump() {}  42. }   ...   50. class Cat implements Jumper{   51. public void jump() {}   52. }. Which three are true?()ACat is-a JumperBCat is-a AnimalCDog is-a JumperDDog is-a AnimalEBeagle has-a JumperFCat has-a AnimalGBeagle has-a Tail

单选题11. class Animal { public String noise() { return “peep”; } }  12. class Dog extends Animal {  13. public String noise() { return “bark”; }  14. }  15. class Cat extends Animal {  16. public String noise() { return “meow”; }  17. }  .....  30. Animal animal = new Dog();  31. Cat cat = (Cat)animal;  32. System.out.printIn(cat.noise());  What is the result?()A peepB barkC meowD Compilation fails.E An exception is thrown at runtime.

多选题Which three demonstrate an “is a” relationship?()Apublic class X { }  public class Y extends X { }Bpublic interface Shape { }  public interface Rectangle extends Shape{ }Cpublic interface Color { }  public class Shape { private Color color; }Dpublic interface Species { }  public class Animal { private Species species; }Epublic class Person { } public class Employee {  public Employee(Person person) { }Finterface Component { }  class Container implements Component { private Component[] children; }

单选题在Java中,类Animal中的方法printA()定义如下:  public void printA() {    Int a=10;    Int result =10%3;    System.out.println(result); }  在类Dog中方法printA()定义如下:  public void printA() {   Int a=10;    System.out.println(a/3); }  Dog类的定义如下:  Class Dog extends Animal{…}.  Animal animal=new Dog();  animal.printA();  以上语句输出结果为()。A 0B 1C 2D3E3.3333

多选题Which two demonstrate an “is a” relationship?()Apublic interface Person { }  public class Employee extends Person { }Bpublic interface Shape { }  public class Employee extends Shape { }Cpublic interface Color { }  public class Employee extends Color { }Dpublic class Species { }  public class Animal (private Species species;)Einterface Component { }  Class Container implements Component ( Private Component[ ]children;  )

单选题现有:  1. interface Animal {  2. void eat();  3. }  4.  5. // insert code here  6.  7. public class HouseCat extends Feline {  8. public void eat() { }  9. }   和五个声明:  abstract class Feline implements Animal { }  abstract class Feline implements Animal { void eat(); }  abstract class Feline implements Animal { public void eat(); }  abstract class Feline implements Animal { public void eat() { } }  abstract class Feline implements Animal { abstract public void eat(); }  分别插入到第5行,有几个可以通过编译?()A0B1C2D3

多选题Which the two demonstrate an “is a” relationship?()Apublic interface Person {}  Public class Employee extends Person {}Bpublic interface Shape {}  public interface Rectangle extends Shape {}Cpublic interface Color {}  public class Shape { private Color color; }Dpublic class Species {}  public class Animal { private Species species; }Einterface Component {} Class Container implements Component {private Component [] children;

多选题10. interface Jumper { public void jump(); }  ......  20. class Animal {}  ......  30. class Dog extends Animal { 31. Tail tail; 32. }  ......  40. class Beagle extends Dog implements Jumper {  41. public void jump() { }  42. }  .......  50. class Cat implements Jumper {  51. public void jump() { }  52. }  Which three are true?()ACat is-a AnimalBCat is-a JumperCDog is-a AnimalDDog is-a JumperECat has-a AnimalFBeagle has-a TailGBeagle has-a Jumper

单选题interface Animal {  void soundOff();  }  class Elephant implements Animal {  public void soundOff() {  System.out.println(“Trumpet”);  }  }  class Lion implements Animal {  public void soundOff() { System.out.println(“Roar”);  }  }  class Alpha1 {  static Animal get( String choice ) {  if ( choice.equalsIgnoreCase( “meat eater” )) {  return new Lion();  } else {  return new Elephant();  }  }  }  Which compiles?()A new Animal().soundOff();B Elephant e = new Alpha1();C Lion 1 = Alpha.get(“meat eater”);D new Alpha1().get(“veggie”).soundOff();

单选题现有:  1.  interface Animal  f      2.    void eat();      3.    }      4.  5.  // insert code here      6.  7. public class HouseCat implements Feline  {      8.    public void eat()    {  }     9.  }  和以下三个接口声明:  interface Feline extends Animal  (  )  interface Feline extends Animal  {void eat();    }  interface Feline extends Animal  {void eat()    {  }  }   分别插入到第5行,有多少行可以编译?A  0B  1C  2D  3

单选题现有:  interface Animal {       void eat () ;       }       //insert code here       public class HouseCat extends Feline {       public void eat() { }       }  和五个申明  abstract class Feline implements Animal { }  abstract  class  Feline  implements  Animal  {  void eat () ;  }  abstract class Feline implements Animal { public void eat();}  abstract class Feline implements Animal { public void eat() {}  }  abstract class Feline implements Animal { abstract public void eat();} 结果为:()A1B2C3D4

单选题1. interface Animal {   2. void eat();   3. }   4.   5. // insert code here   6.   7. public class HouseCat implements Feline {   8. public void eat() { }   9. }   和以下三个接口声明:   interface Feline extends Animal { }   interface Feline extends Animal { void eat(); }   interface Feline extends Animal { void eat() { } }   分别插入到第 5 行,有多少行可以编译?()A0B1C2D3

填空题Animal welfare was a low-rated trust factor partly because consumers were reluctant to pay extra money for “animal friendly” products.____

单选题1. class Animal { Animal getOne() { return new Animal(); } }  2. class Dog extends Animal {  3. // insert code here   4. }  5.  6. class AnimalTest {  7. public static void main(String [] args) {  8. Animal [] animal = { new Animal(), new Dog() } ;  9. for( Animal a : animal) {  10. Animal x = a.getOne();  11. }  12. }  13. }  和代码:  3a. Dog getOne() {  return new Dog();  }  3b. Animal getOne() {  return new Dog();  }  第 3 行中插入的哪项将编译且运行无异常?()A3a行B3b行C3a行或3b行D既非3a,也非3b

单选题class Animal{ Animal getOne(){return new Animal();}}   class Dog extends Animal{   //insert code here   }   class AnimalTest{   public static void main(String[] args){   Animal[] animal={ new Animal(), new Dog()};   for(Animal a:animal){   Animal x= a.getOne();   }   }   }   和代码:   3a.Dog getOne() { return new Dog();}   3b.Animal getOne() { return new Dog();}   第3行中插入的哪项编译且运行无异常?A3a行或3b行B既非3a,也非3bC3a行D3b行