Click the Exhibit button.
Given the fully-qualified class names:
com.foo.bar.Dog
com.foo.bar.blatz.Book
com.bar.Car
com.bar.blatz.Sun
Which graph represents the correct directory structure for a JAR file from which those classes can be used by the compiler and JVM?
Answer : C
A programmer has an algorithm that requires a java.util.List that provides an efficient implementation of add(0, object), but does NOT need to support quick random access.
What supports these requirements?
Answer : C
Given:
11. public static Iterator reverse(List list) {
12. Collections.reverse(list);
13. return list.iterator();
14. }
15. public static void main(String[] args) {
16. List list = new ArrayList();
17. list.add("1"); list.add("2"); list.add("3");
18. for (Object obj: reverse(list))
19. System.out.print(obj + ", ");
20. }
What is the result?
Answer : C
A programmer needs to create a logging method that can accept an arbitrary number of arguments. For example, it may be called in these ways: logIt("log message1"); logIt("log message2","log message3"); logIt("log message4","log message5","log message6");
Which declaration satisfies this requirement?
Answer : A
Given:
11. abstract class Vehicle { public int speed() { return 0; }}
12. class Car extends Vehicle { public int speed() { return 60; }}
13. class RaceCar extends Car { public int speed() { return 150; }}
...
21. RaceCar racer = new RaceCar();
22. Car car = new RaceCar();
23. Vehicle vehicle = new RaceCar();
24. System.out.println(racer.speed() + ", " + car.speed()
25. + ", " + vehicle.speed());
What is the result?
Answer : A
Given:
10. abstract class A {
11. abstract void a1();
12. void a2() { }
13. }
14. class B extends A {
15. void a1() { }
16. void a2() { }
17. }
18. class C extends B { void c1() { } }
and:
A x = new B(); C y = new C(); A z = new C();
What are four valid examples of polymorphic method calls? (Choose four.)
Answer : A,B,C,D
Given:
1. public class Score implements Comparable<Score> {
2. private int wins, losses;
3. public Score(int w, int l) { wins = w; losses = l; }
4. public int getWins() { return wins; }
5. public int getLosses() { return losses; }
6. public String toString() {
7. return "<" + wins + "," + losses + ">";
8. }
9. // insert code here
10. }
Which method will complete this class?
Answer : C
A class games.cards.Poker is correctly defined in the jar file Poker.jar. A user wants to execute the main method of Poker on a UNIX system using the command: java games.cards.Poker
What allows the user to do this?
Answer : C
Given:
10. public class Foo {
11. static int[] a;
12. static { a[0]=2; }
13. public static void main( String[] args ) {}
14. }
Which exception or error will be thrown when a programmer attempts to run this code?
Answer : D
Given:
10. package com.sun.scjp;
11. public class Geodetics {
12. public static final double DIAMETER = 12756.32; // kilometers
13. }
Which two correctly access the DIAMETER member of the Geodetics class? (Choose two.)
Answer : A,D
Given:
12. public class Test {
13. public enum Dogs {collie, harrier};
14. public static void main(String [] args) {
15. Dogs myDog = Dogs.collie;
16. switch (myDog) {
17. case collie:
18. System.out.print("collie ");
19. case harrier:
20. System.out.print("harrier ");
21. }
22. }
23. }
What is the result?
Answer : C
Click the Exhibit button.
Which statement is true about the classes and interfaces in the exhibit?
Answer : D
Given:
11. public class Ball{
12. public enum Color { RED, GREEN, BLUE };
13. public void foo(){
14. // insert code here
15. { System.out.println(c); }
16. }
17. }
Which code inserted at line 14 causes the foo method to print RED, GREEN, and BLUE?
Answer : A
Which three statements are true? (Choose three.)
Answer : A,B,G