QUESTION NO: 61
Exhibit
1. public class SyncTest{
2. public static void main(String[] args) {
3. final StringBuffer s1= new StringBuffer();
4. final StringBuffer s2= new StringBuffer();
5. new Thread () {
6. public void run() {
7. synchronized(s1) {
8. s2.append(“A”);
9. synchronized(s2) {
10. s2.append(“B”);
11. System.out.print(s1);
12. System.out.print(s2);
13. }
14. }
15. }
16. }.start();
17. new Thread() {
18. public void run() {
19. synchronized(s2) {
20. s2.append(“C”);
21. synchronized(s1) {
22. s1.append(“D”);
23. System.out.print(s2);
24. System.out.print(s1);
25. }
26. }
27. }
28. }.start();
29. }
30. }
Which two statements are true? (Choose Two)
A. The program prints “ABBCAD”
B. The program prints “CDDACB”
C. The program prints “ADCBADBC”
D. The output is a non-deterministic point because of a possible deadlock condition.
E. The output is dependent on the threading model of the system the program is running on.
Answer: D, B
QUESTION NO: 62
Which method in the Thread class is used to create and launch a new thread of execution?
A. Run();
B. Start();
B. Execute();
C. Run(Runnable r);
D. Start(Runnable r);
E. Execute(Thread t);
Answer: B
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QUESTION NO: 63
Given:
5. String foo = “base”;
6. foo.substring(0,3);
7. foo.concat(“ket”)
8.
Type the value of foo at line 8.
Answer: BASE
QUESTION NO: 64
Which code determines the int value foo closest to, but not greater than, a double value bar?
A. Int foo = (int) Math.max(bar);
B. Int foo = (int) Math.min(bar);
C. Int foo = (int) Math.abs(bar);
D. Int foo = (int) Math.ceil(bar);
E. Int foo = (int) Math.floor(bar);
F. Int foo = (int) Math.round(bar);
Answer: E
QUESTION NO: 65
Which statement is true?
A. A flow layout can be used to position a component that should resize horizontally when the
container is resized.
B. A grid layout can be used to position a component tat should maintain a constant size even when
the container is resized.
C. A border layout can be used to position component that should maintain a constant size even when
the container is resized.
D. The grid bag layout can be used to give a grid-like layout which differs from the normal grid in
that individual rows and columns can have unique sizes.
E. If two components are placed in the same column of a grid bag layout, and one component resizes
horizontally, then the other component must resize horizontally.
Answer: D
QUESTION NO: 66
Given an ActionEvent, which method allows you to identify the affected Component?
A. Public class getClass()
B. Public Object getSource()
C. Public Component getSource()
D. Public Component getTarget()
E. Public Component getComponent()
F. Public Component getTargetComponent()
Answer: B
QUESTION NO: 67
Exhibit:
1. import java.awt.*;
2.
3. public class Test extends Frame {
4. public Test() {
5. add(new Label(“Hello”) );
6. add(new TextField(“Hello”) );
7. add(new Button(“Hello”) );
8. pack();
9. show();
10. }
11.
12. public static void main(String args[]) {
13. new Test ();
14. }
15. )
What is the result?
A. The code will not compile.
B. A Window will appear containing only a Button.
C. An IllegalArgumentException is thrown at line 6.
D. A Window button will appear but will not contain the Label, TextField, or Button.
E. A Window will appear containing a Label at the top, a TextField below the Label, and a Button
below the TextField.
F. A Window will appear containing a Label on the left, a TextField to the right of the Label, and a
button to the right of the TextField.
Answer: B
QUESTION NO: 68
Exhibit:
1. class A {
2. public int getNumber(int a) {
3. return a + 1;
4. }
5. }
6.
7. class B extends A {
8. public int getNumber (int a) {
9. return a + 2
10. }
11.
12. public static void main (String args[]) {
13. A a = new B();
14. System.out.printIn(a.getNumber(0));
15. }
16. }
What is the result?
A. Compilation succeeds and 1 is printed.
B. Compilation succeeds and 2 is printed.
C. An error at line 8 causes compilation to fail.
D. An error at line 13 causes compilation to fail.
E. An error at line 14 causes compilation to fail.
Answer: B
QUESTION NO: 69
Given:
1. class BaseClass{
2. private float x= 1.0f;
3. protected void setVar (float f) {x = f;}
4. }
5. class SubClass exyends BaseClass {
6. private float x = 2.0f;
7. //insert code here
8. }
Which two are valid examples of method overriding? (Choose Two)
A. Void setVar(float f) {x = f;}
B. Public void setVar(int f) {x = f;}
C. Public void setVar(float f) {x = f;}
D. Public double setVar(float f) {x = f;}
E. Public final void setVar(float f) {x = f;}
F. Protected float setVar() {x=3.0f; return 3.0f; }
Answer: C, E
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