Oracle Oracle Certifications 1Z0-819 Questions & Answers

• Question 41:

  Which set of commands is necessary to create and run a custom runtime image from Java source files?

  A. java, jdeps

  B. javac, jlink

  C. jar, jlink

  D. javac, jar

  Correct Answer: B

  Reference: https://blogs.oracle.com/jtc/automating-the-creation-of-jdk9-reduced-runtime-images-in-netbeans

• Question 42:

  Which two are successful examples of autoboxing? (Choose two.)

  A. String a = "A";

  B. Integer e = 5;

  C. Float g = Float.valueOf(null);

  D. Double d = 4;

  E. Long c = 23L;

  F. Float f = 6.0;

  Correct Answer: AB

• Question 43:

  Given the content:

  

  What is the result?

  

  A. Option A

  B. Option B

  C. Option C

  D. Option D

  E. Option E

  Correct Answer: DE

• Question 44:

  Given:

  

  What is the result?

  A. 2,34,34,5

  B. 2,34,54,5

  C. 2,54,54,5

  D. 2,34,54,3

  Correct Answer: C

  

• Question 45:

  Which code is correct?

  A. Runnable r = "Message" > System.out.println();

  B. Runnable r = () > System.out::print;

  C. Runnable r = () -> {System.out.println("Message");};

  D. Runnable r = > System.out.println("Message");

  E. Runnable r = {System.out.println("Message")};

  Correct Answer: C

  Reference: https://www.oracle.com/technical-resources/articles/java/architect-lambdas-part1.html

• Question 46:

  Which code fragment compiles?

  

  A. Option A

  B. Option B

  C. Option C

  D. Option D

  Correct Answer: D

  

• Question 47:

  Given these declarations:

  

  and these two code fragments: Fragment 1:

  

  Fragment 2:

  

  Which code fragment is preferred and why?

  A. Fragment 1 because it is shorter.

  B. Fragment 2 because it prevents SQL injection.

  C. Fragment 2 because it explicitly specifies the SQL types of the column values.

  D. Fragment 1 because it is more performant.

  Correct Answer: B

• Question 48:

  Given:

  var fruits = List.of("apple", "orange", "banana", "lemon");

  You want to examine the first element that contains the character n. Which statement will accomplish this?

  A. String result = fruits.stream().filter(f > f.contains("n")).findAny();

  B. fruits.stream().filter(f > f.contains("n")).forEachOrdered(System.out::print);

  C. Optional result = fruits.stream().filter(f > f.contains ("n")).findFirst ();

  D. Optional result = fruits.stream().anyMatch(f > f.contains("n"));

  Correct Answer: B

  

• Question 49:

  Assuming the Widget class has a getPrice method, this code does not compile:

  

  Which two statements, independently, would allow this code to compile? (Choose two.)

  A. Replace line 5 with widgetStream.filter(a > ((Widget)a).getPrice() > 20.00).

  B. Replace line 1 with List widgetStream = widgets.stream();.

  C. Replace line 5 with widgetStream.filter((Widget a) > a.getPrice() > 20.00).

  D. Replace line 4 with Stream widgetStream = widgets.stream();.

  Correct Answer: AD

• Question 50:

  Given:

  LocalDate d1 = LocalDate.of(1997,2,7);

  DateTimeFormatter dtf =

  DateTimeFormatter.ofPattern( /*insert code here*/ );

  System.out.println(dtf.format (d1));

  Which pattern formats the date as Friday 7th of February 1997?

  A. "eeee dd+"th of"+ MMM yyyy"

  B. "eeee dd'th of' MMM yyyy"

  C. "eeee d+"th of"+ MMMM yyyy"

  D. "eeee d'th of' MMMM yyyy"

  Correct Answer: D