Oracle Java SE 1Z0-819 Questions & Answers

• Question 41:

  Given:

  

  What is the result?

  A. The compilation fails.

  B. 1.99,2.99,0

  C. 1.99,2.99,0.0

  D. 1.99,2.99

  Correct Answer: A

  

• Question 42:

  Given:

  

  You want to obtain the Stream object on reading the file. Which code inserted on line 1 will accomplish this?

  A. var lines = Files.lines(Paths.get(INPUT_FILE_NAME));

  B. Stream lines = Files.readAllLines(Paths.get(INPUT_FILE_NAME));

  C. var lines = Files.readAllLines(Paths.get(INPUT_FILE_NAME));

  D. Stream lines = Files.lines(INPUT_FILE_NAME);

  Correct Answer: C

• Question 43:

  Which code fragment added to line 1 enables the code to compile and print Hello Joe?

  

  A. Option A

  B. Option B

  C. Option C

  D. Option D

  Correct Answer: C

• Question 44:

  var numbers = List.of(0,1,2,3,4,5,6,7,8,9);

  You want to calculate the average of numbers.

  Which two codes will accomplish this? (Choose two.)

  A. double avg = numbers.stream().parallel().averagingDouble(a > a);

  B. double avg = numbers.parallelStream().mapToInt (m > m).average().getAsDouble ();

  C. double avg = numbers.stream().mapToInt (i > i).average().parallel();

  D. double avg = numbers.stream().average().getAsDouble();

  E. double avg = numbers.stream().collect(Collectors.averagingDouble(n > n));

  Correct Answer: BD

  

• Question 45:

  Given:

  

  Which two lines cause compilation errors? (Choose two.)

  A. line 12

  B. line 6

  C. line 9

  D. line 8

  E. line 7

  Correct Answer: BE

• Question 46:

  Given: And the code fragment:

  

  

  Which situation will occur on code fragment execution?

  A. Livelock

  B. Deadlock

  C. Race Condition

  D. Starvation

  Correct Answer: D

• Question 47:

  Given the Customer table structure:

  ID Number Primary Key NAME Text Nullable Given code fragment:

  

  Which statement inserted on line 14 sets NAME column to a NULL value?

  A. Stmt.setNull(2, java,sql. Types, VARCHAR);

  B. Stmt.setNull(2 string, class);

  C. Stmt.setNull(2, null);

  D. Stmt.setNull(2, java.lang, string);

  Correct Answer: A

• Question 48:

  Which describes a characteristic of setting up the Java development environment?

  A. Setting up the Java development environment requires that you also install the JRE.

  B. The Java development environment is set up for all operating systems by default.

  C. You set up the Java development environment for a specific operating system when you install the JDK.

  D. Setting up the Java development environment occurs when you install an IDE before the JDK.

  Correct Answer: D

  Reference: https://docs.oracle.com/javame/8.1/sdk-dev-guide/install.htm

• Question 49:

  A bookstore's sales are represented by a list of Sale objects populated with the name of the customer and the books they purchased.

  public class Sale {

  private String customer;

  private List items;

  // constructor, setters and getters not shown

  }

  public class Book {

  private String name;

  private double price;

  // constructor, setters and getters not shown

  }

  Given a list of Sale objects, tList, which code fragment creates a list of total sales for each customer in ascending order?

  

  A. Option A

  B. Option B

  C. Option C

  D. Option D

  Correct Answer: C

• Question 50:

  Given:

  

  You want the code to produce this output: John Joe Jane Which code fragment should be inserted on line 1 and line 2 to produce the output?

  A. Insert Comparator on line 1. Insert public int compare(Person p1, Person p2) { return p1.name.compare(p2.name); } on line 2.

  B. Insert Comparator on line 1.

  Insert

  public int compareTo(Person person) {

  return person.name.compareTo(this.name);

  }

  on line 2.

  C. Insert Comparable on line 1. Insert public int compare(Person p1, Person p2) { return p1.name.compare(p2.name); } on line 2.

  D. Insert Comparator on line 1. Insert public int compare(Person person) { return person.name.compare(this.name); } on line 2.

  Correct Answer: B

  Reference: https://www.coursehero.com/file/p320ss6/Override-public-int-compareTo- Person-other-Compare-this-objects-name-to-others/