Oracle Oracle Certifications 1Z0-819 Questions & Answers

• Question 21:

  Given:

  

  and checkQuality(QUALITY.A); and Which code fragment can be inserted into the switch statement to print Best?

  

  A. QUALITY.A.ValueOf()

  B. A

  C. A.toString()

  D. QUALITY.A

  Correct Answer: B

• Question 22:

  Given the code fragment:

  

  Which can replace line 11?

  A. UnaryOperator uo = (var x ) -> (x * 3);

  B. UnaryOperatoruo = var x -> { return x 3 ; };

  C. UnaryOperatoruo = x -> { return x * 3; };

  D. UnaryOperatoruo = (int x) -> x * 3;

  Correct Answer: A

• Question 23:

  Given:

  

  Which statement on line 1 enables this code fragment to compile?

  A. Function function = String::toUpperCase;

  B. UnaryOperator function = s > s.toUpperCase();

  C. UnaryOperator function = String::toUpperCase;

  D. Function function = m > m.toUpperCase();

  Correct Answer: C

  

• Question 24:

  Given:

  

  What is the output?

  A. null

  B. A NoSuchElementException is thrown at run time.

  C. Duke

  D. A NullPointerException is thrown at run time.

  Correct Answer: C

  

• Question 25:

  Given:

  

  Which would cause s to be AQCD?

  A. s.replace(s.indexOf("A"), s.indexOf("C"), "Q");

  B. s.replace(s.indexOf("B"), s.indexOf("C"), "Q");

  C. s.replace(s.indexOf("B"), s.indexOf("B"), "Q");

  D. s.replace(s.indexOf("A"), s.indexOf("B"), "Q");

  Correct Answer: B

• Question 26:

  Given:

  

  What is the output?

  A. :APPLE:ORANGE:BANANA appleorangebanana

  B. :APPLE:ORANGE:BANANA

  C. APPLE:apple ORANGE:orange BANANA:banana

  D. appleorangebanana :APPLE:ORANGE:BANANA

  E. apple:APPLE orange:ORANGE banana:BANANA

  Correct Answer: E

• Question 27:

  Given:

  

  Assuming that this code compiles correctly, which three statements are true? (Choose three.)

  A. A cannot be abstract.

  B. A cannot be final.

  C. B cannot be abstract.

  D. B cannot be final.

  E. B is a subtype of A.

  F. A is A is a subtype of B.a subtype of B.

  Correct Answer: BCE

  The correct answers are B. A cannot be final, C. B cannot be abstract, and E. B is a subtype of A.

  Since the code compiles correctly, the method build in the BuilderImpl class must be a valid implementation of the method declared in the Question70 interface. This means that the return type of the build method in the BuilderImpl class, which is B, must be a subtype of the return type of the build method in the Builder interface, which is A. Therefore, option E is correct.

• Question 28:

  Given:

  

  What is the result?

  A. Joe Joe

  B. null Mary

  C. Joe Marry

  D. null null

  Correct Answer: A

  

• Question 29:

  Given: /code/a/Test.java containing:

  

  and

  /code/b/Best.java

  containing:

  package b;

  public class Best { }

  Which is the valid way to generate bytecode for all classes?

  A. java /code/a/Test.java

  B. javac -d /code /code/a/Test

  C. java /code/a/Test.java /code/b/Best.java

  D. java -cp /code a.Test

  E. javac -d /code /code/a/Test.java /code/b/Best.java

  F. javac -d /code /code/a/Test.java

  Correct Answer: E

• Question 30:

  

  Given:

  String originalPath = "data\\projects\\a-project\\..\\..\\another-project";

  Path path = Paths.get(originalPath);

  System.out.print(path.normalize());

  What is the result?

  A. data\another-project

  B. data\projects\a-project\another-project

  C. data\\projects\\a-project\\..\\..\\another-project

  D. data\projects\a-project\..\..\another-project

  Correct Answer: D