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.

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.


参考解析

解析: 暂无解析

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