网友您好, 请在下方输入框内输入要搜索的题目:

题目内容 (请给出正确答案)

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?() 

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

参考答案

更多 “ 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?() A、3a行B、3b行C、3a行或3b行D、既非3a,也非3b” 相关考题
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______。

考题 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(){}}

考题 ( 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 】 。

考题 1. Everyone in our class ________ .A. like singingB. likes play footballC. like watch TVD. likes playing games

考题 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【 】

考题 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{};}

考题 1. public class Target {  2. private int i = 0;  3. public int addOne() {  4. return ++i;  5. }  6. }  And:  1. public class Client {  2. public static void main(String[] args) {  3. System.out.println(new Target().addOne());  4. }  5. }  Which change can you make to Target without affecting Client?() A、 Line 4 of class Target can be changed to return i++;B、 Line 2 of class Target can be changed to private int i = 1;C、 Line 3 of class Target can be changed to private int addOne() {D、 Line 2 of class Target can be changed to private Integer i = 0;

考题 1. public interface A {  2. public void doSomething(String thing);  3. }  1. public class AImpl implements A {  2. public void doSomething(String msg) { }  3. }  1. public class B {  2. public A doit() {  3. // more code here  4. }  5.  6. public String execute() { 7. // more code here  8. }  9. }  1. public class C extends B {  2. public AImpl doit() {  3. // more code here  4. }  5.  6. public Object execute() {  7. // more code here  8. }  9. }  Which statement is true about the classes and interfaces in the exhibit?() A、 Compilation will succeed for all classes and interfaces.B、 Compilation of class C will fail because of an error in line 2.C、 Compilation of class C will fail because of an error in line 6.D、 Compilation of class AImpl will fail because of an error in line 2.

考题 1. public class a {  2. public void method1() {  3. try {  4. B b=new b();  5. b.method2();  6. // more code here  7. } catch (TestException te) {  8. throw new RuntimeException(te);  9. }  10. }  11. }  1. public class b {  2. public void method2() throws TestException {  3. // more code here  4. }  5. }  1. public class TestException extends Exception {  2. }  Given:  31. public void method() {  32. A a=new a();  33. a.method1();  34. }  Which is true if a TestException is thrown on line 3 of class b?()A、 Line 33 must be called within a try block.B、 The exception thrown by method1 in class a is not required to be caught.C、 The method declared on line 31 must be declared to throw a RuntimeException.D、 On line 5 of class a, the call to method2 of class b does not need to be placed in a try/catch block.

考题 现自:  1.  interface Color {  }      2. interface Weight  {  }      3.  //insert code here    和以下足六个声明:  class Boat extends Color, extends Weight  {  }     class Boat extends Color and Weight  {  }      class Boat extends Color, Weight  {  }  class Boat implements Color,  implements Weight  {  }     class Boat implements Color and Weight  {  }      class Boat implements Color, Weight  {  }    分别插入到第3行,有多少行可以编译? () A、  0B、  1C、  2D、  3

考题 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();

考题 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.

考题 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;  )

考题 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

考题 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.

考题 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; }

考题 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  2D 3E 3.3333

考题 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;  )

考题 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?()A 0B 1C 2D 3

考题 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;

考题 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

考题 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();

考题 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

考题 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:()A 1B 2C 3D 4

考题 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?()A 0B 1C 2D 3

考题 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?()A 3a行B 3b行C 3a行或3b行D 既非3a,也非3b

考题 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?A 3a行或3b行B 既非3a,也非3bC 3a行D 3b行

考题 单选题In a class of 160 seniors, the ratio of boys to girls is 3 to 5. In the junior class, the ratio of boys to girls is 3 to 2. When the two classes are combined, the ratio of boys to girls is 1 to 1. How many students are in the junior class?A 400B 360C 200D 180E 160