单选题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?()A Compilation of class A fails.B Line 28 prints the value 3 to System.out.C Line 28 prints the value 1 to System.out.D A runtime error occurs when line 25 executes.E Compilation fails because of an error on line 28.

单选题
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?()
A

 Compilation of class A fails.

B

 Line 28 prints the value 3 to System.out.

C

 Line 28 prints the value 1 to System.out.

D

 A runtime error occurs when line 25 executes.

E

 Compilation fails because of an error on line 28.


参考解析

解析: 暂无解析

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