Update 1Z0-851 Exam Study Guides With New Update Exam Questions

Q1. Given:

5. import java.util.*;

6. public class SortOf {

7. public static void main(String[] args) {

8. ArrayList<Integer> a = new ArrayList<Integer>();

9. a.add(1); a.add(5); a.add(3);

11. Collections.sort(a);

12. a.add(2);

13. Collections.reverse(a);

14. System.out.println(a);

15. }

16. }

What is the result?

A. [1, 2, 3, 5]

B. [2, 1, 3, 5]

C. [2, 5, 3, 1]

D. [5, 3, 2, 1]

E. [1, 3, 5, 2]

F. Compilation fails.

G. An exception is thrown at runtime.

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Q2. 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?

A. java.lang.StackOverflowError

B. java.lang.IllegalStateException

C. java.lang.ExceptionInInitializerError

D. java.lang.ArrayIndexOutOfBoundsException

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Q3. A company that makes Computer Assisted Design (CAD) software has, within its application, some utility classes that are used to perform 3D rendering tasks. The company's chief scientist has just improved the performance of one of the utility classes' key rendering algorithms, and has assigned a programmer to replace the old algorithm with the new algorithm. When the programmer begins researching the utility classes, she is happy to discover that the algorithm to be replaced exists in only one class. The programmer reviews that class's API, and replaces the old algorithm with the new algorithm, being careful that her changes adhere strictly to the class's API. Once testing has begun, the programmer discovers that other classes that use the class she changed are no longer working properly. What design flaw is most likely the cause of these new bugs?

A. Inheritance

B. Tight coupling

C. Low cohesion

D. High cohesion

E. Loose coupling

F. Object immutability

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Q4. Given:

1. public class Threads5 {

2. public static void main (String[] args) {

3. new Thread(new Runnable() {

4. public void run() {

5. System.out.print("bar");

6. }}).start();

7. }

8. }

What is the result?

A. Compilation fails.

B. An exception is thrown at runtime.

C. The code executes normally and prints "bar".

D. The code executes normally, but nothing prints.

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Q5. Given:

21. class Money {

22. private String country = "Canada";

23. public String getC() { return country; }

24. }

25. class Yen extends Money {

26. public String getC() { return super.country; }

27. }

28. public class Euro extends Money {

29. public String getC(int x) { return super.getC(); }

30. public static void main(String[] args) {

31. System.out.print(new Yen().getC() + " " + new Euro().getC());

32. }

33. }

What is the result?

A. Canada

B. null Canada

C. Canada null

D. Canada Canada

E. Compilation fails due to an error on line 26.

F. Compilation fails due to an error on line 29.

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Q6. 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? (Choose three.)

A. int foo() { /* more code here */ }

B. void foo() { /* more code here */ }

C. public void foo() { /* more code here */ }

D. private void foo() { /* more code here */ }

E. protected void foo() { /* more code here */ }

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Q7. Given:

22. public void go() {

23. String o = "";

24. z:

25. for(int x = 0; x < 3; x++) {

26. for(int y = 0; y < 2; y++) {

27. if(x==1) break;

28. if(x==2 && y==1) break z;

29. o = o + x + y;

30. }

31. }

32. System.out.println(o);

33. }

What is the result when the go() method is invoked?

A. 00

B. 0001

C. 000120

D. 00012021

E. Compilation fails.

F. An exception is thrown at runtime.

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Q8. Which three statements are true? (Choose three.)

A. A final method in class X can be abstract if and only if X is abstract.

B. A protected method in class X can be overridden by any subclass of X.

C. A private static method can be called only within other static methods in class X.

D. A non-static public final method in class X can be overridden in any subclass of X.

E. A public static method in class X can be called by a subclass of X without explicitly referencing the class

X.

F. A method with the same signature as a private final method in class X can be implemented in a

subclass of X.

G. A protected method in class X can be overridden by a subclass of X only if the subclass is in the same

package as X.

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Q9. 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?

A. public int compareTo(Object o){/*more code here*/}

B. public int compareTo(Score other){/*more code here*/}

C. public int compare(Score s1,Score s2){/*more code here*/}

D. public int compare(Object o1,Object o2){/*more code here*/}

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Q10. Click the Exhibit button. Given the fully-qualified class names: com.foo.bar.Dog com.foo.bar.blatz.Bookcom.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?

A. Jar A

B. Jar B

C. Jar C

D. Jar D

E. Jar E

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