11. class Cup { }  12. class PoisonCup extends Cup { }  21. public void takeCup(Cup c) {  22. if(c instanceof PoisonCup) {  23. System.out.println(”Inconceivable!”);  24. } else if(c instanceof Cup) {  25. System.out.println(”Dizzying intellect!”);  26. } else {  27. System.exit(0);  28. }  29. }  And the execution of the statements:  Cup cup = new PoisonCup(); takeCup(cup);  What is the output?() A、 Inconceivable!B、 Dizzying intellect!C、 The code runs with no output.D、 An exception is thrown at runtime.E、 Compilation fails because of an error in line 22.

11. class Cup { }  12. class PoisonCup extends Cup { }  21. public void takeCup(Cup c) {  22. if(c instanceof PoisonCup) {  23. System.out.println(”Inconceivable!”);  24. } else if(c instanceof Cup) {  25. System.out.println(”Dizzying intellect!”);  26. } else {  27. System.exit(0);  28. }  29. }  And the execution of the statements:  Cup cup = new PoisonCup(); takeCup(cup);  What is the output?() 

  • A、 Inconceivable!
  • B、 Dizzying intellect!
  • C、 The code runs with no output.
  • D、 An exception is thrown at runtime.
  • E、 Compilation fails because of an error in line 22.

相关考题:

阅读下列代码段,选出该代码段的正确文件名( )。 class A { void methodl() { System.out.println("methodl in class A"); } } public class B { void method2() { System.out.println("method2 in class B"); } public static void main(String args[]) { System.out.println("main in class B"); } }A.A.javaB.A.classC.B.classD.B.java

11.classCup{}12.classPoisonCupextendsCup{}21.publicvoidtakeCup(Cupc){22.if(cinstanceofPoisonCup){23.System.out.println(”Inconceivable!”);24.}elseif(cinstanceofCup){25.System.out.println(”Dizzyingintellect!”);26.}else{27.System.exit(0);28.}29.}Andtheexecutionofthestatements:Cupcup=newPoisonCup();takeCup(cup);Whatistheoutput?()A.Inconceivable!B.Dizzyingintellect!C.Thecoderunswithnooutput.D.Anexceptionisthrownatruntime.E.Compilationfailsbecauseofanerrorinline22.

interface A{int x = 0;}class B{int x =1;}class C extends B implements A {public void pX(){System.out.println(x);}public static void main(String[] args) {new C().pX();}}

考虑如下代码:class Tree{}class Pine extends Tree{}class Oak extends Tree{}public class Forest {public static void main( String[] args ) {Tree tree = new Pine();if( tree instanceof Pine )System.out.println( "Pine" );if( tree instanceof Tree )System.out.println( "Tree" );if( tree instanceof Oak )System.out.println( "Oak" );elseSystem.out.println( "Oops" );}}则输出结果中有哪些?A.Pine B.Tree C.Forest D.Oops E.无输出

设有程序如下: public class jzh0319 { public static void main(String args[]) { subClass sc=new subClass(); } } class superClass { superClass() { System.out.println("父类");} } class subClass extends superClass { subClass() {System.out.println("子类"); } } 其输出结果只有一行。()此题为判断题(对,错)。

class MyThread extends Thread {  public void run() { System.out.println(“AAA”); }  public void run(Runnable r) { System.out.println(“BBB”); }  public static void main(String[] args) {  new Thread(new MyThread()).start();  }  }   What is the result?()  A、 AAAB、 BBBC、 Compilation fails.D、 The code runs with no output.

10. interface A { void x(); }  11. class B implements A { public void x() { } public voidy() { } }  12. class C extends B { public void x() {} }  And:  20. java.util.List list = new java.util.ArrayList();  21. list.add(new B());  22. list.add(new C());  23. for (A a:list) {  24. a.x();  25. a.y();;  26. }  What is the result?()  A、 The code runs with no output.B、 An exception is thrown at runtime.C、 Compilation fails because of an error in line 20.D、 Compilation fails because of an error in line 21.E、 Compilation fails because of an error in line 23.F、 Compilation fails because of an error in line 25.

1. public class GoTest {  2. public static void main(String[] args) {  3. Sente a = new Sente(); a.go();  4. Goban b = new Goban(); b.go();  5. Stone c = new Stone(); c.go();  6. }  7. } 8.  9. class Sente implements Go {  10. public void go() { System.out.println(”go in Sente.”); }  11. }  12.  13. class Goban extends Sente {  14. public void go() { System.out.println(”go in Goban”); }  15. }  16.  17. class Stone extends Goban implements Go { }  18.  19. interface Go { public void go(); }  What is the result?() A、 go in Goban  go in Sente go in SenteB、 go in Sente  go in Sente go in GobanC、 go in Sente  go in Goban go in GobanD、 go in Goban go in Goban go in SenteE、 Compilation fails because of an error in line 17.

class A {  public A() {  System.out.println(“hello from a”);  }  }  class B extends A {  public B () {  System.out.println(“hello from b”);  super();  }  }  public class Test {  public static void main(String args[]) {  A a = new B();  }  }   What is the result when main is executed?()  A、 Compilation fails.B、 hello from aC、 hello from bD、 hello from b hello from aE、 hello from a hello from b

class TestA {  public void start() { System.out.println(”TestA”); }  }  public class TestB extends TestA {  public void start() { System.out.println(”TestB”); } public static void main(String[] args) {  ((TestA)new TestB()).start();  }  }  What is the result?() A、 TestAB、 TestBC、 Compilation fails.D、 An exception is thrown at runtime.

1. public class Test { 2. public static String output =””; 3.  4. public static void foo(int i) { 5. try { 6. if(i==1) { 7. throw new Exception(); 8. } 9. output += “1”; 10. } 11. catch(Exception e) { 12. output += “2”; 13. return; 14. } 15. finally { 16. output += “3”;17. } 18. output += “4”; 19. } 20.  21. public static void main(String args[]) { 22. foo(0); 23. foo(1); 24.  25. }26. } What is the value of the variable output at line 23?()

1. class Alpha { void m1() {} }   2. class Beta extends Alpha { void m2() { } }   3. class Gamma extends Beta { }   4.   5. class GreekTest {   6. public static void main(String [] args) {   7. a Alpha [] a = {new Alpha(), new Beta(), new Gamma() };   8. for(Alpha a2 : a) {   9. a2.m1();   10. if (a2 instanceof Beta || a2 instanceof Gamma)   11. //insert code here   12. }   13. }   14. }   哪一行代码插入到第11行,将编译但是会在运行时产生异常?()  A、 a2.m2();B、 ((Beta)a2).m2();C、 ((Alpha)a2).m2();D、 ((Gamma)a2).m2();

10. public class SuperCaic {  11. protected static int multiply(int a, int b) { return a * b; }  12. }  and:  20. public class SubCalc extends SuperCalc {  21. public static int multiply(int a, int b) {  22. int c = super.multiply(a, b);  23. return c;  24. }  25. }  and:  30. SubCalc sc = new SubCalc();  31. System.out.println(sc.multiply(3,4));  32. System.out.println(SubCalc.multiply(2,2));  What is the result?()A、 12 4B、 The code runs with no output.C、 An exception is thrown at runtime.D、 Compilation fails because of an error in line 21.E、 Compilation fails because of an error in line 22.F、 Compilation fails because of an error in line 31.

11. class Payload {  12. private int weight;  13. public Payload(int wt) { weight = wt; }  13. public void setWeight(mt w) { weight = w; }  15. public String toString { return Integer.toString(weight); }  16. }  17.  18. public class TestPayload {  19. static void changePayload(Payload p) { 20. /* insert code here */ 21. }  22.  23. public static void main(String[] args) {  24. Payload p = new Payload();  25. p.setWeight(1024);  26. changePayload(p);  27. System.out.println(”The value of p is “+ p);  28. }  29. }  Which statement, placed at line 20, causes the code to print “The value of p is 420.”?() A、 p.setWeight(420);B、 p.changePayload(420);C、 p = new Payload(420);D、 Payload.setWeight(420);E、 p = Payload.setWeight(420);F、 p = new Payload(); p.setWeight(420);

11. abstract class Vehicle { public int speed() { return 0; } }  12. class Car extends Vehicle { public int speed() { return 60; } }  13. class RaceCar extends Car { public int speed() { return 150; }}  ......  21. RaceCar racer = new RaceCar();  22. Car car = new RaceCar();  23. Vehicle vehicle = new RaceCar();  24. System.out.println(racer.speed() + “, „ + car.speed()  25. + “, “+ vehicle.speed());  What is the result?() A、 0, 0,0B、 150, 60, 0C、 Compilation fails.D、 150, 150, 150E、 An exception is thrown at runtime.

现有:      class TestA  {  public void start()  {  System.out.println("TestA");  }     }  public class TestB extends TestA  {  public void start()  {  System.out.println("TestB");  }     public static void main (string[]  args)  (     ((TestA)new TestB()).start();     )     }  运行结果是哪项?()     A、  TeStAB、  TeStBC、编译失败D、运行时抛出异常

11. class Person {  12. String name = “No name‟;  13. public Person(String nm) { name = nm; }  14. }  15.  16. class Employee extends Person {  17. String emplD = “0000”;  18. public Employee(String id) { empID = id; }  19. }  20.  21. public class EmployeeTest {  22. public static void main(String[] args) {  23. Employee e = new Employee(”4321”);  24. System.out.println(e.empID);  25. }  26. }  What is the result?() A、 4321B、 0000C、 An exception is thrown at runtime.D、 Compilation fails because of an error in line 18.

Given the following code, write a line of code that, when inserted at the indicated location, will make the overriding method in Extension invoke the overridden method in class Base on the current object.   class Base {   public void print( ) {   System.out.println("base");   }   }   class Extention extends Base {   public void print( ) {   System.out.println("extension");   // insert line of implementation here   }   }   public class Q294d {   public static void main(String args[]) {   Extention ext = new Extention( );   ext.print( );   }   }   Fill in a single line of implementation.()

10. class Inner {  11. private int x;  12. public void setX( int x) { this.x = x; }  13. public int getX() { return x; }  14. }  15.  16. class Outer {  17. private Inner y;  18. public void setY( Inner y) { this.y = y; }  19. public Inner getY() { return y; }  20. }  21.  22. public class Gamma {  23. public static void main( String[] args) { 24. Outer o = new Outer(); 25. Inner i = new Inner();  26.int n=10;  27. i.setX(n);  28. o.setY(i);  29. // insert code here  30. System.out.println( o.getY().getX());  31. }  32. }  Which three code fragments, added individually at line 29, produce the output 100?()A、 n = 100;B、 i.setX( 100);C、 o.getY().setX( 100);D、 i = new Inner(); i.setX( 100);E、 o.setY( i); i = new Inner(); i.setX( 100);F、 i = new Inner(); i.setX( 100); o.setY( i);

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.

10. interface Foo {  11. int bar();  12. }  13.  14. public class Beta {  15.  16. class A implements Foo {  17. public int bar() { return 1; }  18. }  19.  20. public int fubar( Foo foo) { return foo.bar(); }  21.  22. public void testFoo() {  23.  24. class A implements Foo {  25. public int bar() { return 2; }  26. }  27.  28. System.out.println( fubar( new A())); 29. }  30.  31. public static void main( String[] argv) {  32. new Beta().testFoo();  33. }  34. }  Which three statements are true?()A、 Compilation fails.B、 The code compiles and the output is 2.C、 If lines 16, 17 and 18 were removed, compilation would fail.D、 If lines 24, 25 and 26 were removed, compilation would fail.E、 If lines 16, 17 and 18 were removed, the code would compile and the output would be 2.F、 If lines 24, 25 and 26 were removed, the code would compile and the output would be 1.

多选题10. class Inner {  11. private int x;  12. public void setX( int x) { this.x = x; }  13. public int getX() { return x; }  14. }  15.  16. class Outer {  17. private Inner y;  18. public void setY( Inner y) { this.y = y; }  19. public Inner getY() { return y; }  20. }  21.  22. public class Gamma {  23. public static void main( String[] args) { 24. Outer o = new Outer(); 25. Inner i = new Inner();  26.int n=10;  27. i.setX(n);  28. o.setY(i);  29. // insert code here  30. System.out.println( o.getY().getX());  31. }  32. }  Which three code fragments, added individually at line 29, produce the output 100?()An = 100;Bi.setX( 100);Co.getY().setX( 100);Di = new Inner(); i.setX( 100);Eo.setY( i); i = new Inner(); i.setX( 100);Fi = new Inner(); i.setX( 100); o.setY( i);

单选题10. public class SuperCaic {  11. protected static int multiply(int a, int b) { return a * b; }  12. }  and:  20. public class SubCalc extends SuperCalc {  21. public static int multiply(int a, int b) {  22. int c = super.multiply(a, b);  23. return c;  24. }  25. }  and:  30. SubCalc sc = new SubCalc();  31. System.out.println(sc.multiply(3,4));  32. System.out.println(SubCalc.multiply(2,2));  What is the result?()A 12 4B The code runs with no output.C An exception is thrown at runtime.D Compilation fails because of an error in line 21.E Compilation fails because of an error in line 22.F Compilation fails because of an error in line 31.

单选题现有:      class TestA  {  public void start()  {  System.out.println("TestA");  }     }  public class TestB extends TestA  {  public void start()  {  System.out.println("TestB");  }     public static void main (string[]  args)  (     ((TestA)new TestB()).start();     )     }  运行结果是哪项?()A  TeStAB  TeStBC编译失败D运行时抛出异常

单选题现有:   1.  class Alpha { void m1() {} }   2.  class Beta extends Alpha { void m2() { } }   3.  class Gamma extends Beta { }   4.   5.  class GreekTest {   6.    public static void main(String [] args) {   7.      Alpha [] a = {new Alpha(), new Beta(), new Gamma() };   8.      for(Alpha a2 : a) {   9.        a2.m1();    10.       if (a2 instanceof Beta || a2 instanceof Gamma)    11.         //insert code here   12.     }    13.   }   14. }    哪一行代码插入到第11行,将编译但是会在运行时产生异常?()A a2.m2();B ((Beta)a2).m2();C ((Alpha)a2).m2();D ((Gamma)a2).m2();

多选题10. interface Foo {  11. int bar();  12. }  13.  14. public class Beta {  15.  16. class A implements Foo {  17. public int bar() { return 1; }  18. }  19.  20. public int fubar( Foo foo) { return foo.bar(); }  21.  22. public void testFoo() {  23.  24. class A implements Foo {  25. public int bar() { return 2; }  26. }  27.  28. System.out.println( fubar( new A())); 29. }  30.  31. public static void main( String[] argv) {  32. new Beta().testFoo();  33. }  34. }  Which three statements are true?()ACompilation fails.BThe code compiles and the output is 2.CIf lines 16, 17 and 18 were removed, compilation would fail.DIf lines 24, 25 and 26 were removed, compilation would fail.EIf lines 16, 17 and 18 were removed, the code would compile and the output would be 2.FIf lines 24, 25 and 26 were removed, the code would compile and the output would be 1.

单选题11. class Payload {  12. private int weight;  13. public Payload(int wt) { weight = wt; }  13. public void setWeight(mt w) { weight = w; }  15. public String toString { return Integer.toString(weight); }  16. }  17.  18. public class TestPayload {  19. static void changePayload(Payload p) { 20. /* insert code here */ 21. }  22.  23. public static void main(String[] args) {  24. Payload p = new Payload();  25. p.setWeight(1024);  26. changePayload(p);  27. System.out.println(”The value of p is “+ p);  28. }  29. }  Which statement, placed at line 20, causes the code to print “The value of p is 420.”?()A p.setWeight(420);B p.changePayload(420);C p = new Payload(420);D Payload.setWeight(420);E p = Payload.setWeight(420);F p = new Payload(); p.setWeight(420);