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  (  ) 

题目
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

  0

B

  1

C

  2

D

  3


相似考题
参考答案和解析
正确答案: A
解析: 暂无解析
更多“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  (  )  ”相关问题
  • 第1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、  0
    • B、  1
    • C、  2
    • D、  3

    正确答案:C

  • 第2题:

    1. public class Exception Test {  2. class TestException extends Exception {}  3. public void runTest() throws TestException {}  4. public void test() /* Point X */ {  5. runTest();  6. }  7. }  At Point X on line 4, which code is necessary to make the code compile?()  

    • A、 No code is necessary.
    • B、 throws Exception
    • C、 catch ( Exception e )
    • D、 throws RuntimeException
    • E、 catch ( TestException e)

    正确答案:B

  • 第3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、1
    • B、2
    • C、3
    • D、4

    正确答案:C

  • 第4题:

    1. public class enclosingone (  2. public class insideone{}  3. )  4. public class inertest(  5. public static void main (string[]args)(  6. enclosingone eo= new enclosingone ();  7. //insert code here  8. )  9. )    Which statement at line 7 constructs an instance of the inner class?()  

    • A、 InsideOnew ei= eo.new InsideOn();
    • B、 Eo.InsideOne ei = eo.new InsideOne();
    • C、 InsideOne ei = EnclosingOne.new InsideOne();
    • D、 EnclosingOne.InsideOne ei = eo.new InsideOne();

    正确答案:D

  • 第5题:

    现有:   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、 0
    • B、 1
    • C、 2
    • D、 3

    正确答案:C

  • 第6题:

    单选题
    1. interface A { public void aMethod(); }  2. interface B { public void bMethod(); }  3. interface C extends A,B { public void cMethod(); }  4. class D implements B {  5. public void bMethod() { }  6. }  7. class E extends D implements C {  8. public void aMethod() { }  9. public void bMethod() { }  10. public void cMethod() { }  11. }  What is the result?()
    A

     Compilation fails because of an error in line 3.

    B

     Compilation fails because of an error in line 7.

    C

     Compilation fails because of an error in line 9.

    D

     If you define D e = new E(), then e.bMethod() invokes the version of bMethod()defined in Line 5.

    E

     If you define D e = (D)(new E()),then e.bMethod() invokes the version of bMethod() defined in Line 5.

    F

     If you define D e = (D)(new E()), then e.bMethod() invokes the version of bMethod() defined in Line 9.


    正确答案: A
    解析: 暂无解析

  • 第7题:

    单选题
    1. public class Exception Test {  2. class TestException extends Exception {}  3. public void runTest() throws TestException {}  4. public void test() /* Point X */ {  5. runTest();  6. }  7. }  At Point X on line 4, which code is necessary to make the code compile?()
    A

     No code is necessary.

    B

     throws Exception

    C

     catch ( Exception e )

    D

     throws RuntimeException

    E

     catch ( TestException e)


    正确答案: E
    解析: 暂无解析

  • 第8题:

    单选题
    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.


    正确答案: A
    解析: 暂无解析

  • 第9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

    0

    B

    1

    C

    2

    D

    3


    正确答案: D
    解析: 暂无解析

  • 第10题:

    单选题
    Given classes defined in two different files:  1. package util;  2. public class BitUtils {  3. public static void process(byte[]) { /* more code here */ }  4. }  1. package app;  2. public class SomeApp {  3. public static void main(String[] args) {  4. byte[] bytes = new byte[256];  5. // insert code here  6. }  7. }  What is required at line 5 in class SomeApp to use the process method of BitUtils?()
    A

     process(bytes);

    B

     BitUtils.process(bytes);

    C

     util.BitUtils.process(bytes);

    D

     SomeApp cannot use methods in BitUtils.

    E

     import util.BitUtils.*; process(bytes);


    正确答案: E
    解析: 暂无解析

  • 第11题:

    单选题
    1. public class enclosingone (  2. public class insideone{}  3. )  4. public class inertest(  5. public static void main (string[]args)(  6. enclosingone eo= new enclosingone ();  7. //insert code here  8. )  9. )    Which statement at line 7 constructs an instance of the inner class?()
    A

     InsideOnew ei= eo.new InsideOn();

    B

     Eo.InsideOne ei = eo.new InsideOne();

    C

     InsideOne ei = EnclosingOne.new InsideOne();

    D

     EnclosingOne.InsideOne ei = eo.new InsideOne();


    正确答案: C
    解析: 暂无解析

  • 第12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

    1

    B

    2

    C

    3

    D

    4


    正确答案: C
    解析: 暂无解析

  • 第13题:

    interface Data { public void load(); }  abstract class Info { public abstract void load(); }  Which class correctly uses the Data interface and Info class?() 

    • A、 public class Employee extends Info implements Data { public void load() { /*do something*/ } }
    • B、 public class Employee implements Info extends Data { public void load() { /*do something*/ } }
    • C、 public class Employee extends Info implements Data { public void load() { /*do something */ } public void Info.load() { /*do something*/ } }
    • D、 public class Employee implements Info extends Data { public void Data.load() { /*dsomething */ } public void load() { /*do something */ } }
    • E、 public class Employee implements Info extends Data { public void load() { /*do something */ } public void Info.load(){ /*do something*/ } }
    • F、 public class Employee extends Info implements Data{ public void Data.load() { /*do something*/ } public void Info.load() { /*do something*/ } }

    正确答案:A

  • 第14题:

    1. public class A {  2. public void method1() {  3. B b=new B();  4. b.method2();  5. // more code here  6. }  7. }  1. public class B {  2. public void method2() {  3.C c=new C();  4. c.method3();  5. // more code here  6. }  7. }  1. public class C {  2. public void method3() {  3. // more code here  4. }  5. }  Given:  25. try {  26. A a=new A();  27. a.method1();  28. } catch (Exception e) {  29. System.out.print(”an error occurred”);  30. }  Which two are true if a NullPointerException is thrown on line 3 of class C?()

    • A、 The application will crash.
    • B、 The code on line 29 will be executed.
    • C、 The code on line 5 of class A will execute.
    • D、 The code on line 5 of class B will execute.
    • E、 The exception will be propagated back to line 27.

    正确答案:B,E

  • 第15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

    正确答案:D

  • 第16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、0
    • B、1
    • C、2
    • D、3

    正确答案:D

  • 第17题:

    1. interface A { public void aMethod(); }  2. interface B { public void bMethod(); }  3. interface C extends A,B { public void cMethod(); }  4. class D implements B {  5. public void bMethod() { }  6. }  7. class E extends D implements C {  8. public void aMethod() { }  9. public void bMethod() { }  10. public void cMethod() { }  11. }  What is the result?() 

    • A、 Compilation fails because of an error in line 3.
    • B、 Compilation fails because of an error in line 7.
    • C、 Compilation fails because of an error in line 9.
    • D、 If you define D e = new E(), then e.bMethod() invokes the version of bMethod()defined in Line 5.
    • E、 If you define D e = (D)(new E()),then e.bMethod() invokes the version of bMethod() defined in Line 5.
    • F、 If you define D e = (D)(new E()), then e.bMethod() invokes the version of bMethod() defined in Line 9.

    正确答案:F

  • 第18题:

    单选题
    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.


    正确答案: A
    解析: 暂无解析

  • 第19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

    0

    B

    1

    C

    2

    D

    3


    正确答案: D
    解析: 暂无解析

  • 第20题:

    单选题
    1. public class SimpleCalc {  2. public int value;  3. public void calculate() { value += 7; }  4. } And:  1. public class MultiCalc extends SimpleCalc {  2. public void calculate() { value -= 3; }  3. public void calculate(int multiplier) {  4. calculate();  5. super.calculate();  6. value *=multiplier;  7. }  8. public static void main(String[] args) {  9. MultiCalc calculator = new MultiCalc();  10. calculator.calculate(2);  11. System.out.println(”Value is: “+ calculator.value);  12. }  13. }  What is the result?()
    A

     Value is: 8

    B

     Compilation fails.

    C

     Value is: 12

    D

     Value is: -12

    E

     The code runs with no output.

    F

     An exception is thrown at runtime.


    正确答案: A
    解析: 暂无解析

  • 第21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


    正确答案: C
    解析: 暂无解析

  • 第22题:

    单选题
    现有:   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

     0

    B

     1

    C

     2

    D

     3


    正确答案: A
    解析: 暂无解析

  • 第23题:

    单选题
    interface Data { public void load(); }  abstract class Info { public abstract void load(); }  Which class correctly uses the Data interface and Info class?()
    A

     public class Employee extends Info implements Data { public void load() { /*do something*/ } }

    B

     public class Employee implements Info extends Data { public void load() { /*do something*/ } }

    C

     public class Employee extends Info implements Data { public void load() { /*do something */ } public void Info.load() { /*do something*/ } }

    D

     public class Employee implements Info extends Data { public void Data.load() { /*dsomething */ } public void load() { /*do something */ } }

    E

     public class Employee implements Info extends Data { public void load() { /*do something */ } public void Info.load(){ /*do something*/ } }

    F

     public class Employee extends Info implements Data{ public void Data.load() { /*do something*/ } public void Info.load() { /*do something*/ } }


    正确答案: B
    解析: 暂无解析