单选题1. class A { 2. public byte file Number ( ) { 3. return l; 4. } 5. } 6. 7. Class B extends A { 8. public short getNumber( ) { 9. return 2; 10. } 11. 12. public short getNumber( ) { 13. B b = new B( ); 14. System.out.printIn(b.getNumber( )); 15. } 16. } What is the result()?A
Compilation succeeds and l is printed.B
Compilation succeeds and 2 printed.C
An error at line 8 cause compilation to fail.D
An error at line 14 cause complication to fail.E
Complication succeeds but an exception is thrown at line 14.
第1题:
1. public class A { 2. public void doit() { 3. } 4. public String doit() { 5. return “a”; 6. } 7. public double doit(int x) { 8. return 1.0; 9. } 10.} What is the result?()
第2题:
1. class SuperClass { 2. public a geta() { 3. return new a(); 4. } 5. } 6. class SubClass extends SuperClass { 7. public b geta() { 8. return new b(); 9. } 10. } Which is true?()
第3题:
class A { public byte getNumber () { return 1; } } class B extends A { public short getNumber() { return 2; } public static void main (String args) { B b = new B (); System.out.printIn(b.getNumber()) } } What is the result?()
第4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?()
第5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( )?
第6题:
1. public class A { 2. 3. private int counter = 0; 4. 5. public static int getInstanceCount() { 6. return counter; 7. } 8. 9. public A() { 10. counter++; 11. } 12. 13. } Given this code from Class B: 25.A a1 =new A(); 26. A a2 =new A(); 27. A a3 =new A(); 28. System.out.printIn(A.getInstanceCount() ); What is the result?()
第7题:
Compilation will succeed for all classes and interfaces.
Compilation of class C will fail because of an error in line 2.
Compilation of class C will fail because of an error in line 6.
Compilation of class AImpl will fail because of an error in line 2.
第8题:
Compilation succeeds and 4 is printed.
Compilation succeeds and 43 is printed.
An error on line 9 causes compilation to fail.
An error on line 14 causes compilation to fail.
Compilation succeeds but an exception is thrown at line 9.
第9题:
Value is: 8
Compilation fails.
Value is: 12
Value is: -12
The code runs with no output.
An exception is thrown at runtime.
第10题:
Compilation succeeds and 1 is printed.
Compilation succeeds and 2 is printed.
An error at line 8 causes compilation to fail.
An error at line 14 causes compilation to fail.
Compilation succeeds but an exception is thrown at line 14.
第11题:
Compilation of class A fails.
Line 28 prints the value 3 to System.out.
Line 28 prints the value 1 to System.out.
A runtime error occurs when line 25 executes.
Compilation fails because of an error on line 28.
第12题:
Compilation succeeds and 1 is printed.
Compilation succeeds and 2 is printed.
An error at line 8 causes compilation to fail.
An error at line 13 causes compilation to fail.
An error at line 14 causes compilation to fail.
第13题:
1. class A { 2. public byte getNumber () { 3. return 1; 4. } 5. } 6. 7. class B extends A { 8. public short getNumber() { 9. return 2; 10. } 11. 12. public static void main (String args[]) { 13. B b = new B (); 14. System.out.printIn(b.getNumber()) 15. } 16. } What is the result?()
第14题:
1. class Pizza { 2. java.util.ArrayList toppings; 3. public final void addTopping(String topping) { 4. toppings.add(topping); 5. } 6. } 7. public class PepperoniPizza extends Pizza { 8. public void addTopping(String topping) { 9. System.out.println(”Cannot add Toppings”); 10. } 11. public static void main(String[] args) { 12. Pizza pizza = new PepperoniPizza(); 13. pizza.addTopping(”Mushrooms”); 14. } 15. } What is the result?()
第15题:
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?()
第16题:
class A { public byte getNumber() { return 1; } } class B extends A { public short getNumber() { return 2; } public static void main(String args[]) { B b = new B(); System.out.println(b.getNumber()); } } What is the result?()
第17题:
1. class A { 2. public byte file Number ( ) { 3. return l; 4. } 5. } 6. 7. Class B extends A { 8. public short getNumber( ) { 9. return 2; 10. } 11. 12. public short getNumber( ) { 13. B b = new B( ); 14. System.out.printIn(b.getNumber( )); 15. } 16. } What is the result()?
第18题:
1
2
An exception is thrown at runtime.
Compilation fails because of an error in line 8.
Compilation fails because of an error in line 14.
第19题:
Compilation will succeed if a extends b.
Compilation will succeed if b extends a.
Compilation will always fail because of an error in line 7.
Compilation will always fail because of an error in line 8.
第20题:
Compilation fails.
Cannot add Toppings
The code runs with no output.
A NullPointerException is thrown in Line 4.
第21题:
Compilation succeeds and 1 is printed.
Compilation succeeds and 2 is printed.
An error at line 8 causes compilation to fail.
An error at line 14 causes compilation to fail.
Compilation succeeds but an exception is thrown at line 14.
第22题:
Compilation succeeds and l is printed.
Compilation succeeds and 2 printed.
An error at line 8 cause compilation to fail.
An error at line 14 cause complication to fail.
Complication succeeds but an exception is thrown at line 14.
第23题:
Compilation succeeds and 4 is printed.
Compilation …………… is printed.
An error on line 9 cause compilation to fail.
An error on line 14 cause compilation to fail.
Compilation succeeds but an exception is thrown at line 9.
第24题:
An exception is thrown at runtime.
Compilation fails because of an error in line 7.
Compilation fails because of an error in line 4.
Compilation succeeds and no runtime errors with class A occur.