Compilation fails.
The code compiles and the output is 2.
If lines 16, 17 and 18 were removed, compilation would fail.
If lines 24, 25 and 26 were removed, compilation would fail.
If lines 16, 17 and 18 were removed, the code would compile and the output would be 2.
If lines 24, 25 and 26 were removed, the code would compile and the output would be 1.
第1题:
11. public void addStrings(List list) { 12. list.add(”foo”); 13. list.add(”bar”); 14. } What must you change in this method to compile without warnings?()
第2题:
11. public interface Status { 12. /* insert code here */ int MY_VALUE = 10; 13. } Which three are valid on line 12?()
第3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4题:
10. class Line { 11. public class Point { public int x,y; } 12. public Point getPoint() { return new Point(); } 13. } 14. class Triangle { 15. public Triangle() { 16. // insert code here 17. } 18. } Which code, inserted at line 16, correctly retrieves a local instance of a Point object?()
第5题:
10. interface Foo {} 11. class Alpha implements Foo {} 12. class Beta extends Alpha {} 13. class Delta extends Beta { 14. public static void main( String[] args) { 15. Beta x = new Beta(); 16. // insert code here 17. } 18. } Which code, inserted at line 16, will cause a java.lang.ClassCastException?()
第6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7题:
10. public class Hello { 11. String title; 12. int value; 13. public Hello() { 14. title += “ World”; 15. } 16. public Hello(int value) { 17. this.value = value; 18. title = “Hello”; 19. Hello(); 20. } 21. } and: 30. Hello c = new Hello(5); 31. System.out.println(c.title); What is the result?()
第8题:
10. public class ClassA { 11. public void count(int i) { 12. count(++i); 13. } 14. } And: 20. ClassA a = new ClassA(); 21. a.count(3); Which exception or error should be thrown by the virtual machine?()
第9题:
public class Foo { public int a; public Foo() { a = 3; } public void addFive() { a += 5; } } and: public class Bar extends Foo { public int a; public Bar() { a = 8; } public void addFive() { this.a +=5; } } invoked with: Foo foo = new Bar(); foo.addFive(); System.out.println(”Value: “+ foo.a); What is the result?()
第10题:
Given: 10. class One { 11. void foo() { } 12. } 13. class Two extends One { 14. //insert method here 15. } Which three methods, inserted individually at line 14, will correctly complete class Two?()