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?()
第1题:
10. interface Foo { int bar(); } 11. public class Sprite { 12. public int fubar( Foo foo) { return foo.bar(); } 13. public void testFoo() { 14. fubar( 15. // insert code here 16.); 17. } 18. } Which code, inserted at line 15, allows the class Sprite to compile?()
第2题:
1. package foo; 2. 3. import java.util.Vector; 4. 5. private class MyVector extends Vector { 6. int i = 1; 7. public MyVector() { 8. i = 2; 9. } 10. } 11. 12. public class MyNewVector extends MyVector { 13. public MyNewVector () { 14. i = 4; 15. } 16. public static void main (String args []) { 17. MyVector v = new MyNewVector(); 18. } 19. } The file MyNewVector.java is shown in the exhibit. What is the result?()
第3题:
( 10 )已知下列程序的输出结果是 42 ,请将画线处缺失的部分补充完整。
#include
using namespace std;
class Foo {
int value;
public:
Foo( ) : value(0) {}
void setValue(int value)
{ 【 10 】 = value; // 给 Foo 的数据成员 value 赋值 }
void print( ) { cout << value; }
};
int main( )
{
Foo f;
f.setValue(42);
f.print();
return 0;
}
第4题:
11. public class Test { 12. public void foo() { 13. assert false; 14. assert false; 15. } 16. public void bar(){ 17. while(true){ 18. assert false; 19. } 20. assert false; 21. } 22. } What causes compilation to fail?()
第5题:
class One { public One foo() { return this; } } class Two extends One { public One foo() { return this; } } class Three extends Two { // insert method here } Which two methods, inserted individually, correctly complete the Three class?()
第6题:
class Foo { private int x; publicFoo(intx) {this.x=x; } public void setX( int x) { this.x = x; } public int getX() { return x; } } public class Gamma { static Foo fooBar( Foo foo) { foo = new Foo( 100); return foo; } public static void main( String[] args) { Foo foo = new Foo( 300); System.out.print( foo.getX() + “-“); Foo fooFoo = fooBar( foo); System.out.print( foo.getX() + “-“); System.out.print( fooFoo.getX() + “-“); foo = fooBar( fooFoo); System.out.print( foo.getX() + “-“); System.out.prmt( fooFoo.getX()); } } What is the output of this program?()
第7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8题:
A.Foo { public int bar() { return 1; }
B.new Foo { public int bar() { return 1; }
C.new Foo() { public int bar() { return 1; }
D.new class Foo { public int bar() { return 1; }
第9题:
public class Delta { static boolean foo(char c) { System.out.print(c); return true; } public static void main( String[] argv ) { int i =0; for ( foo(‘A’); foo(‘B’)&&(i<2); foo(‘C’)){ i++ ; foo(‘D’); } } } What is the result?()
第10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.”?()