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 functional interface represents an operation that accepts two input arguments, and returns a result?
Answer : B
Explanation
BiFunction<T,U> functional interface represents an operation that accepts two input arguments, and returns a result.
Q 2 - Which of the following functional interface represents a function that accepts a double-valued argument and produces a result?
Answer : A
Explanation
DoubleFunction<R> functional interface represents a function that accepts a double-valued argument and produces a result.
Q 3 - Which of the following functional interface represents an operation on a single double-valued operand that produces a double-valued result?
Answer : B
Explanation
DoubleUnaryOperator functional interface represents an operation on a single double-valued operand that produces a double-valued result.
Q 4 - Which of the following functional interface represents a function that accepts a long-valued argument and produces an int-valued result?
Answer : B
Explanation
LongToIntFunction functional interface represents a function that accepts a long-valued argument and produces an int-valued result.
Q 5 - Which of the following functional interface represents a function that accepts two arguments and produces a long-valued result?
Answer : A
Explanation
ToLongBiFunction<T,U> functional interface represents a function that accepts two arguments and produces a long-valued result.
Q 6 - How will you call a default method of an interface in a class?
A - Using super keyword along with interface name.
Answer : A
Explanation
Using super keyword along with interface name.
Q 7 - Which of the following API represents a simplified date-time API with no complexity of timezone handling in java8?
Answer : A
Explanation
Local − Simplified date-time API with no complexity of timezone handling.
Q 8 - Which of the following is the correct lambda expression which add two numbers and return their sum?
Answer : C
Explanation
Both of the above options are correct.
Answer : A
Explanation
Optional is a container object which is used to contain not-null objects.
Answer : B
Explanation
Optional.isPresent method checks the value is present or not.
