Online 1Z0-809 Practice Test

Question 1

Consider the code of Test.java file:

1. package com.udayan.ocp;

2.

3. class Player {

4. String name;

5. int age;

6.

7. Player() {

8. this.name = "Yuvraj";

9. this.age = 36;

10. }

11.

12. public String toString() {

13. return name + ", " + age;

14. }

15.

16. public Class getClass() {

17. return super.getClass();

18. }

19. }

20.

21. public class Test {

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

23. System.out.println(new Player());

24. }

25. }

What will be the result of compiling and executing Test class?

Options :

A : Compilation error

B : Yuvraj, 36

C : null, 0

D : Text containing @ symbol

Answer: A

Question 2

Given:

class UserException extends Exception { }

class AgeOutOfLimitException extends UserException { }

and the code fragment:

class App {

public void doRegister(String name, int age)

throws UserException, AgeOutOfLimitException {

if (name.length () < 6) {

throw new UserException ();

} else if (age >= 60) {

throw new AgeOutOfLimitException ();

} else {

System.out.println(“User is registered.”);

}

public static void main(String[ ] args) throws UserException {

App t = new App ();

t.doRegister(“Mathew”, 60);

}

What is the result?

Options :

A :

User is registered.

B :

An AgeOutOfLimitException is thrown.

C : A UserException is thrown.

D : A compilation error occurs in the main method.

Answer: B

Question 3

You want to create a singleton class by using the Singleton design pattern. Which two statements enforce the singleton nature of the design? (Choose two.)

Options :

A : Make the class static.

B : Make the constructor private.

C : Override equals() and hashCode() methods of the java.lang.Object class

D : Use a public reference to point to the single instance

E : Implement the Serializable interface

F : Make the single instance created static and final.

Answer: A,B

Question 4

Given:

and the code fragment:

Which two code fragments, when inserted at line n1 independently, enable the code to print

TruckCarBike?

Options :

A : .sorted ((v1, v2) -> v1.getVId() < v2.getVId())

B : .sorted (Comparable.comparing (Vehicle: :getVName)).reversed ()

C :

.map (v -> v.getVid())

.sorted ()

D : .sorted((v1, v2) -> Integer.compare(v1.getVId(), v2.getVid()))

E : .sorted(Comparator.comparing ((Vehicle v) -> v.getVId()))

Answer: A,D

Question 5

Given the code fragment:

public class FileThread implements Runnable {

String fName;

public FileThread(String fName) { this.fName = fName; }

public void run () System.out.println(fName);}

public static void main (String[] args) throws IOException,

InterruptedException {

ExecutorService executor = Executors.newCachedThreadPool();

Stream<Path> listOfFiles = Files.walk(Paths.get(“Java Projects”));

listOfFiles.forEach(line -> {

executor.execute(new FileThread(line.getFileName().toString()));

//

line n1

});

executor.shutdown();

executor.awaitTermination(5, TimeUnit.DAYS); //

line n2

}

The Java Projects directory exists and contains a list of files.

What is the result?

Options :

A : The program throws a runtime exception at line n2.

B : The program prints files names concurrently

C : The program prints files names sequentially.

D : A compilation error occurs at line n1

Answer: B

EXPERTY DESIGNED 1Z0-809 PRACTICE TEST