1Z0-816 Real Exam Questions and Verified Answers

Question 1 Single choice

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<String> function = String::toUpperCase;
D
Function<String> function = m -> m.toUpperCase();

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Correct answer: C

Explanation

Question 2 Single choice

Given:

List<String> longlist = List.of("Hello","World","Beat");
List<String> shortlist = new ArrayList<>();

Which code fragment correctly forms a short list of words containing the letter "e"?

A
Option A
B
Option B
C
Option C
D
Option D

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Correct answer: C

Question 3 Multiple choice

Given:

Which two are correct? (Choose two.)

A
Option A
B
Option B
C
Option C
D
Option D
E
Option E

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Correct answers: C, D

Question 4 Single choice

Given:

Which is true?

A
System.out is the standard output stream. The stream is open only when System.out is called.
B
System.in cannot reassign the other stream.
C
System.out is an instance of java.io.OutputStream by default.
D
System.in is the standard input stream. The stream is already open.

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Correct answer: D

Explanation

References:
https://www.geeksforgeeks.org/java-lang-system-class-java/

Question 5 Single choice

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<String> result = fruits.stream().filter(f -> f.contains("n")).findFirst ();
D
Optional<String> result = fruits.stream().anyMatch(f -> f.contains("n"));

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Correct answer: B

Explanation

Question 6 Multiple choice

Given:

Which two interfaces can be used in lambda expressions? (Choose two.)

A
MyInterface1
B
MyInterface3
C
MyInterface5
D
MyInterface2
E
MyInterface4

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Correct answers: C, D

Explanation

References:
https://dzone.com/articles/functional-interface-and-lambda-expression

Question 7 Single choice

Given:

Which statement on line 1 enables this code to compile?

A
Function<Integer, Integer> f = n -> n * 2;
B
Function<Integer> f = n -> n * 2;
C
Function<int> f = n -> n * 2;
D
Function<int, int> f = n -> n * 2;
E
Function f = n -> n * 2;

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Correct answer: A

Explanation

Question 8 Single choice

Given:

Which is true about line 1?

A
If the value is not present, a NoSuchElementException is thrown at run time.
B
It always executes the System.out::print statement.
C
If the value is not present, a NullPointerException is thrown at run time.
D
If the value is not present, nothing is done.

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Correct answer: D

Explanation

Question 9 Multiple choice

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));

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Correct answers: B, D

Explanation

Question 10 Single choice

Which is a proper JDBC URL?

A
jdbe.mysql.com://localhost:3306/database
B
http://localhost.mysql.com:3306/database
C
http://localhostmysql.jdbc:3306/database
D
jdbc:mysql://localhost:3306/database

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Correct answer: D

Explanation

References:
https://vladmihalcea.com/jdbc-driver-connection-url-strings/