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)
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
peep
B
bark
C
meow
D
Compilation fails.
E
An exception is thrown at runtime.
参考答案
参考解析
解析:
暂无解析
更多 “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.” 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
阅读下面代码 abstract class Person { public Person(String n) { name=n; } public______String getDescription(); public String getName() { return name; } private String name; } 在下画线处应填入的修饰符是A.staticB.abstractC.protectedD.final
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( );}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
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
Assume that country is set for each class. Given: 10. public class Money { 11. private String country, name; 12. public getCountry() { return country; } 13.} and: 24. class Yen extends Money { 25. public String getCountry() { return super.country; } 26. } 27. 28. class Euro extends Money { 29. public String getCountry(String timeZone) { 30. return super.getCountry(); 31. } 32. } Which two are correct?()A、 Yen returns correct values.B、 Euro returns correct values.C、 An exception is thrown at runtime.D、 Yen and Euro both return correct values.E、 Compilation fails because of an error at line 25.F、 Compilation fails because of an error at line 30.
考题
public class Employee{ private String name; public Employee(String name){ this.name = name; } public String getName(){ return name; } } public class Manager extends Employee{ public Manager(String name){ System.out.println(getName()); } } 执行语句new Manager(“smith”)后程序的输出是哪项?() A、 smithB、 nullC、 编译错误D、 name
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
public class X { public X aMethod() { return this;} } public class Y extends X { } Which two methods can be added to the definition of class Y?()A、 public void aMethod() {}B、 private void aMethod() {}C、 public void aMethod(String s) {}D、 private Y aMethod() { return null; }E、 public X aMethod() { return new Y(); }
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
现有: 1. abstract class Color { 2.protected abstract String getRGB(); 3. } 4. 5. public class Blue extends Color { 6. //insert code here 7. } 和四个声明: public String getRGB() { return "blue"; } String getRGB() { return "blue"; ) private String getRGB() { return "blue"; } protected String getRGB() { return "blue"; ) 分别插入到第6行,有几个可以通过编译?() A、 0B、 1C、 2D、 3
考题
public class Plant { private String name; public Plant(String name) { this.name = name; } public String getName() { return name; } } public class Tree extends Plant { public void growFruit() { } public void dropLeaves() { } } Which is true?() A、 The code will compile without changes.B、 The code will compile if public Tree() { Plant(); } is added to the Tree class.C、 The code will compile if public Plant() { Tree(); } is added to the Plant class.D、 The code will compile if public Plant() { this(”fern”); } is added to the Plant class.E、 The code will compile if public Plant() { Plant(”fern”); } is added to the Plant class.
考题
单选题1. class A { 2. public String toString () { 3. return “4”; 4. } 5. } 6. class B extends A { 7. public String toString () { 8. return super.toString() + “3”; 9. } 10. } 11. public class Test { 12. public static void main(String[]args) { 13. System.out.printIn(new B()); 14. } 15. } What is the result?()A
Compilation succeeds and 4 is printed.B
Compilation succeeds and 43 is printed.C
An error on line 9 causes compilation to fail.D
An error on line 14 causes compilation to fail.E
Compilation succeeds but an exception is thrown at line 9.
考题
单选题public class Employee{ private String name; public Employee(String name){ this.name = name; } public String getName(){ return name; } } public class Manager extends Employee{ private String department; public Manager(String name,String department){ this.department = department; super(name); System.out.println(getName()); } } 执行语句new Manager(“smith”,”SALES”)后程序的输出是哪项?()A
smithB
nullC
SALESD
编译错误
考题
单选题现有: 1. abstract class Color { 2.protected abstract String getRGB(); 3. } 4. 5. public class Blue extends Color { 6. //insert code here 7. } 和四个声明: public String getRGB() { return "blue"; } String getRGB() { return "blue"; ) private String getRGB() { return "blue"; } protected String getRGB() { return "blue"; ) 分别插入到第6行,有几个可以通过编译?()A
0B
1C
2D
3
考题
单选题10. interface Foo { int bar(); } 11. public class Sprite { 12. public int fubar( Foo foo) { return foo.bar(); } 13. public void testFoo() { 14. fubar( 15. // insert code here 16.); 17. } 18. } Which code, inserted at line 15, allows the class Sprite to compile?()A
Foo { public int bar() { return 1; } }B
new Foo { public int bar() { return 1; } }C
newFoo() { public int bar(){return 1; } }D
new class Foo { public int bar() { return 1; } }
考题
单选题1. class A { 3. public String to String() { 4. return “4”; 5. } 6. } 7. class B extends A { 8. public String toString() { 9. return super.toString() + “3”; 10. } 11. } 12. public class Test { 13. public static void main (String[] args) { 14. System.out.printIn(new B()); 15. } 16. } What is the result( )?A
Compilation succeeds and 4 is printed.B
Compilation …………… is printed.C
An error on line 9 cause compilation to fail.D
An error on line 14 cause compilation to fail.E
Compilation succeeds but an exception is thrown at line 9.
考题
单选题public class Employee{ private String name; public Employee(String name){ this.name = name; } public String getName(){ return name; } } public class Manager extends Employee{ public Manager(String name){ System.out.println(getName()); } } 执行语句new Manager(“smith”)后程序的输出是哪项?()A
smithB
nullC
编译错误D
name
考题
多选题public class X { public X aMethod() { return this;} } public class Y extends X { } Which two methods can be added to the definition of class Y?()Apublic void aMethod() {}Bprivate void aMethod() {}Cpublic void aMethod(String s) {}Dprivate Y aMethod() { return null; }Epublic X aMethod() { return new Y(); }
考题
单选题public class Plant { private String name; public Plant(String name) { this.name = name; } public String getName() { return name; } } public class Tree extends Plant { public void growFruit() { } public void dropLeaves() { } } Which is true?()A
The code will compile without changes.B
The code will compile if public Tree() { Plant(); } is added to the Tree class.C
The code will compile if public Plant() { Tree(); } is added to the Plant class.D
The code will compile if public Plant() { this(”fern”); } is added to the Plant class.E
The code will compile if public Plant() { Plant(”fern”); } is added to the Plant class.
考题
单选题10. public class ClassA { 11. public void methodA() { 12. ClassB classB = new ClassB(); 13. classB.getValue(); 14. } 15. } And: 20. class ClassB { 21. public ClassC classC; 22. 23. public String getValue() { 24. return classC.getValue(); 25. } 26. } And: 30. class ClassC { 31. public String value; 32. 33. public String getValue() { 34. value = “ClassB”; 35. return value; 36. } 37. } Given: ClassA a = new ClassA(); a.methodA(); What is the result?()A
Compilation fails.B
ClassC is displayed.C
The code runs with no output.D
An exception is thrown at runtime.
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
多选题public class Car { private int wheelCount; private String vin; public Car(String vin) { this.vin = vin; this.wheelCount = 4; } public String drive() { return “zoom-zoom”; } public String getInfo() { return “VIN: “+ vin + “wheels: “+ wheelCount; } } And: public class MeGo extends Car { public MeGo(String vin) { this.wheelCount = 3; } } What two must the programmer do to correct the compilation errors?()Ainsert a call to this() in the Car constructorBinsert a call to this() in the MeGo constructorCinsert a call to super() in the MeGo constructorDinsert a call to super(vin) in the MeGo constructorEchange the wheelCount variable in Car to protectedFchange line 3 in the MeGo class to super.wheelCount = 3;
热门标签
最新试卷