Compilation fails due to an error in line 23.
Compilation fails due to an error in line 29.
A ClassCastException occurs in line 29.
A ClassCastException occurs in line 31.
The value of all four objects prints in natural order.
第1题:
package foo; import java.util.Vector; private class MyVector extends Vector { int i = 1; public MyVector() { i = 2; } } public class MyNewVector extends MyVector { public MyNewVector() { i = 4; } public static void main(String args[]) { MyVector v = new MyNewVector(); } } What is the result?()
第2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3题:
test
null
An exception is thrown at runtime.
Compilation fails because of an error in line 1.
Compilation fails because of an error in line 4.
Compilation fails because of an error in line 5.
第4题:
Canada
null Canada
Canada null
Canada Canada
Compilation fails due to an error on line 26.
Compilation fails due to an error on line 29.
第5题:
1 2 3
Compilation fails because of an error in line 12.
Compilation fails because of an error in line 13.
Compilation fails because of an error in line 14.
A ClassCastException is thrown at runtime.
第6题:
Compilation of class A fails.
Line 28 prints the value 3 to System.out.
Line 28 prints the value 1 to System.out.
Compilation fails because of an error on line 28.
A runtime error occurs when line 25 executes.
第7题:
Compilation succeeds.
Compilation fails because of an error at line 5.
Compilation fails because of an error at line 6.
Compilation fails because of an error at line 14.
Compilation fails because of an error at line 17.
第8题:
Canada
null Canada
Canada null
Canada Canada
Compilation fails due to an error on line 26.
第9题:
X, followed by an Exception.
No output, and an Exception is thrown.
Compilation fails due to an error on line 14.
Compilation fails due to an error on line 16.
Compilation fails due to an error on line 17.
第10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11题:
Compilation fails due to an error in line 23.
Compilation fails due to an error in line 29.
A ClassCastException occurs in line 29.
A ClassCastException occurs in line 31.
The value of all four objects prints in natural order.
第12题:
The code runs with no output.
An exception is thrown at runtime.
Compilation fails because of an error in line 20.
Compilation fails because of an error in line 21.
Compilation fails because of an error in line 23.
Compilation fails because of an error in line 25.
第13题:
11.public static void main(String[]args){ 12.Object obj=new int[]{1,2,3}; 13.int[] someArray=(int[])obj; 14.for(inti:someArray)System.out.print(i+"") 15.} What is the result?()
第14题:
Compilation succeeds.
Compilation fails due to multiple errors.
Compilation fails due to an error only on line 20.
Compilation fails due to an error only on line 21.
Compilation fails due to an error only on line 22.
第15题:
Compilation fails due to an error in line 23.
Compilation fails due to an error in line 29.
A ClassCastException occurs in line 29.
A ClassCastException occurs in line 31.
The value of all four objects prints in natural order.
第16题:
B
B, followed by an Exception.
Compilation fails due to an error on line 9.
Compilation fails due to an error on line 14.
An Exception is thrown with no other output.
第17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18题:
Line 26 prints "a" to System.out.
Line 26 prints "b" to System.out.
An exception is thrown at line 26 at runtime.
Compilation of class A will fail due to an error in line 6.
第19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20题:
Compilation fails because of an error in line 13.
A ClassCastException is thrown at runtime.
1 2 3
Compilation fails because of an error in line 14.
Compilation fails because of an error in line 12.
第21题:
An Exception is thrown with no other output
followed by an Exception
Compilation fails due to an error on line 9
Compilation fails due to an error on line 14
第22题:
Compilation succeeds.
Compilation fails due to multiple errors.
Compilation fails due to an error only on line 20.
Compilation fails due to an error only on line 21.
Compilation fails due to an error only on line 22.
Compilation fails due to an error only on line 12.
第23题:
True
Not true
An exception is thrown at runtime.
Compilation fails because of an error at line 12.
Compilation fails because of an error at line 19.
第24题:
B
The code runs with no output.
Compilation fails because of an error in line 12.
Compilation fails because of an error in line 15.
Compilation fails because of an error in line 18.