Oracle Oracle Certifications 1Z0-809 Questions & Answers

• Question 161:

  Given:

  public final class IceCream {

  public void prepare() {}

  }

  public class Cake {

  public final void bake(int min, int temp) {}

  public void mix() {}

  }

  public class Shop {

  private Cake c = new Cake ();

  private final double discount = 0.25;

  public void makeReady () { c.bake(10, 120); }

  }

  public class Bread extends Cake {

  public void bake(int minutes, int temperature) {}

  public void addToppings() {}

  }

  Which statement is true?

  A. A compilation error occurs in IceCream.

  B. A compilation error occurs in Cake.

  C. A compilation error occurs in Shop.

  D. A compilation error occurs in Bread

  E. All classes compile successfully.

  Correct Answer: D

• Question 162:

  Which two statements are true about localizing an application? (Choose two.)

  A. Support for new regional languages does not require recompilation of the code.

  B. Textual elements (messages and GUI labels) are hard-coded in the code.

  C. Language and region-specific programs are created using localized data.

  D. Resource bundle files include data and currency information.

  E. Language codes use lowercase letters and region codes use uppercase letters.

  Correct Answer: AE

  Reference: http://docs.oracle.com/javase/7/docs/technotes/guides/intl/

• Question 163:

  Which statement is true about java.util.stream.Stream?

  A. A stream cannot be consumed more than once.

  B. The execution mode of streams can be changed during processing.

  C. Streams are intended to modify the source data.

  D. A parallel stream is always faster than an equivalent sequential stream.

  Correct Answer: B

• Question 164:

  Which statement is true about the single abstract method of the java.util.function.Function interface?

  A. It accepts one argument and returns void.

  B. It accepts one argument and returns boolean.

  C. It accepts one argument and always produces a result of the same type as the argument.

  D. It accepts an argument and produces a result of any data type.

  Correct Answer: D

• Question 165:

  Given the code fragments:

  class Caller implements Callable {

  String str;

  public Caller (String s) {this.str=s;}

  public String call()throws Exception { return str.concat ("Caller");}

  }

  class Runner implements Runnable {

  String str;

  public Runner (String s) {this.str=s;}

  public void run () { System.out.println (str.concat ("Runner"));}

  }

  and

  public static void main (String[] args) InterruptedException, ExecutionException {

  ExecutorService es = Executors.newFixedThreadPool(2);

  Future f1 = es.submit (new Caller ("Call"));

  Future f2 = es.submit (new Runner ("Run"));

  String str1 = (String) f1.get();

  String str2 = (String) f2.get(); //line n1

  System.out.println(str1+ ":" + str2);

  }

  What is the result?

  A. The program prints: Run Runner Call Caller : null And the program does not terminate.

  B. The program terminates after printing: Run Runner Call Caller : Run

  C. A compilation error occurs at line n1.

  D. An Execution is thrown at run time.

  Correct Answer: A

• Question 166:

  Given:

  public class Canvas implements Drawable {

  public void draw () { }

  }

  public abstract class Board extends Canvas { }

  public class Paper extends Canvas {

  protected void draw (int color) { }

  }

  public class Frame extends Canvas implements Drawable {

  public void resize () { }

  }

  public interface Drawable {

  public abstract void draw ();

  }

  Which statement is true?

  A. Board does not compile.

  B. Paper does not compile.

  C. Frame does not compile.

  D. Drawable does not compile.

  E. All classes compile successfully.

  Correct Answer: E

• Question 167:

  Given the code fragment:

  List str = Arrays.asList ("my", "pen", "is", "your', "pen");

  Predicate test = s -> {

  int i = 0;

  boolean result = s.contains ("pen");

  System.out.print(i++) + ":");

  return result;

  };

  str.stream()

  .filter(test)

  .findFirst()

  .ifPresent(System.out ::print);

  What is the result?

  A. 0 : 0 : pen

  B. 0 : 1 : pen

  C. 0 : 0 : 0 : 0 : 0 : pen

  D. 0 : 1 : 2 : 3 : 4 :

  E. A compilation error occurs.

  Correct Answer: A

• Question 168:

  Given the code fragment:

  List empDetails = Arrays.asList("100, Robin, HR",

  "200, Mary, AdminServices",

  "101, Peter, HR");

  empDetails.stream()

  .filter(s-> s.contains("1"))

  .sorted()

  .forEach(System.out::println); //line n1

  What is the result?

  A. 100, Robin, HR 101, Peter, HR

  B. A compilation error occurs at line n1.

  C. 100, Robin, HR 101, Peter, HR 200, Mary, AdminServices

  D. 100, Robin, HR 200, Mary, AdminServices 101, Peter, HR

  Correct Answer: A

• Question 169:

  Given:

  interface Rideable {Car getCar (String name); }

  class Car {

  private String name;

  public Car (String name) {

  this.name = name;

  }

  }

  Which code fragment creates an instance of Car?

  A. Car auto = Car ("MyCar"): : new;

  B. Car auto = Car : : new; Car vehicle = auto : : getCar("MyCar");

  C. Rideable rider = Car : : new; Car vehicle = rider.getCar("MyCar");

  D. Car vehicle = Rideable : : new : : getCar("MyCar");

  Correct Answer: C

• Question 170:

  Given the code fragments:

  public class Book implements Comparator {

  String name;

  double price;

  public Book () {}

  public Book(String name, double price) {

  this.name = name;

  this.price = price;

  }

  public int compare(Book b1, Book b2) {

  return b1.name.compareTo(b2.name);

  }

  public String toString() {

  return name + ":" + price;

  }

  }

  and

  Listbooks = Arrays.asList (new Book ("Beginning with Java", 2), new book ("A

  Guide to Java Tour", 3));

  Collections.sort(books, new Book());

  System.out.print(books);

  What is the result?

  A. [A Guide to Java Tour:3.0, Beginning with Java:2.0]

  B. [Beginning with Java:2, A Guide to Java Tour:3]

  C. A compilation error occurs because the Book class does not override the abstract method compareTo ().

  D. An Exception is thrown at run time.

  Correct Answer: A