Java Operators

Java Control Statements

Object Oriented Programming

Java Built-in Classes

Java File Handling

Java Error & Exceptions

Java Multithreading

Java Synchronization

Java Networking

Java Collections

Java Interfaces

Java Data Structures

Java Collections Algorithms

Advanced Java

Java Miscellaneous

Java APIs & Frameworks

Java Class References

Java Useful Resources

Java 8 Online Quiz

Following quiz provides Multiple Choice Questions (MCQs) related to Java 8. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the quiz.

Q 1 - Which of the following is correct about Java8?

A - Lambda expression - Adds functional processing capability to Java.

B - Method references - Referencing functions by their names instead of invoking them directly. Using functions as parameter.

C - Default method - Interface to have default method implementation.

D - All of the above.

Answer : D

Explanation

All of the above options are correct.

Q 2 - Which of the following functional interface represents a function that accepts a double-valued argument and produces an int-valued result?

A - DoubleFunction<R>

B - DoublePredicate

C - DoubleSupplier

D - DoubleToIntFunction

Answer : D

Explanation

DoubleToIntFunction functional interface represents a function that accepts a double-valued argument and produces an int-valued result.

Q 3 - Which of the following functional interface represents a function that accepts one argument and produces a result?

A - DoubleToLongFunction

B - DoubleUnaryOperator

C - Function<T,R>

D - IntBinaryOperator

Answer : C

Explanation

Function<T,R> functional interface represents a function that accepts one argument and produces a result.

Q 4 - Which of the following functional interface represents an operation on a single int-valued operand that produces an int-valued result?

A - IntToDoubleFunction

B - IntToLongFunction

C - IntUnaryOperator

D - LongBinaryOperator

Answer : C

Explanation

IntUnaryOperator functional interface represents an operation on a single int-valued operand that produces an int-valued result.

Q 5 - Which of the following functional interface represents a function that accepts two arguments and produces an int-valued result?

A - ToDoubleBiFunction<T,U>

B - ToDoubleFunction<T>

C - ToIntBiFunction<T,U>

D - ToIntFunction<T>

Answer : C

Explanation

ToIntBiFunction<T,U> functional interface represents a function that accepts two arguments and produces an int-valued result.

Q 6 - Which of the following is correct about streams in java8?

A - Intermediate operation's function is to take input, process them, and return output to the target.

B - collect() method is a terminal operation which is normally present at the end of the pipelining operation to mark the end of the stream.

C - Both of the above.

D - None of the above.

Answer : C

Explanation

Both of the above options are correct.

Q 7 - Which of the following class implements a decoder for decoding byte data using the Base64 encoding scheme in Java8?

Answer : A

Explanation

static class Base64.Decoder - This class implements a decoder for decoding byte data using the Base64 encoding scheme as specified in RFC 4648 and RFC 2045.

Q 8 - Using lambda expression, you can refer to final variable or effectively final variable (which is assigned only once).

A - false

B - true

Answer : B

Explanation

Using lambda expression, you can refer to final variable or effectively final variable (which is assigned only once).

Q 9 - Stream supports aggregate operations like filter, map, limit, reduce, find and match.

A - false

B - true

Answer : B

Explanation

Stream supports aggregate operations like filter, map, limit, reduce, find, match, and so on.

Q 10 - Optional.of method throws NullPointerException if passed parameter is null.

A - true

B - false

Answer : A

Explanation

Optional.of method throws NullPointerException if passed parameter is null.

java8_questions_answers.htm