Java Operators

Java Control Statements

Object Oriented Programming

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Java File Handling

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Java Multithreading

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Advanced Java

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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 an operation that accepts a single input argument and returns no result?

A - BooleanSupplier

B - Consumer<T>

C - DoubleBinaryOperator

D - DoubleConsumer

Answer : B

Explanation

Consumer<T> functional interface represents an operation that accepts a single input argument and returns no 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 long-valued operand that produces a long-valued result?

A - LongToDoubleFunction

B - LongToIntFunction

C - LongUnaryOperator

D - ObjDoubleConsumer<T>

Answer : C

Explanation

LongUnaryOperator functional interface represents an operation on a single long-valued operand that produces a long-valued result.

Q 5 - Which of the following functional interface represents a predicate (Boolean-valued function) of one argument?

A - ObjIntConsumer<T>

B - ObjLongConsumer<T>

C - Predicate<T>

D - Supplier<T>

Answer : C

Explanation

Predicate<T> functional interface represents a predicate (Boolean-valued function) of one argument.

Q 6 - What is the purpose of forEach method of stream in java 8?

A - Iterate each element of the stream.

B - Map each element to its corresponding result.

C - Eliminate elements based on a criteria

D - Reduce the size of the stream

Answer : A

Explanation

Stream has provided a new method 'forEach' to iterate each element of the stream.

Q 7 - Which of the following is correct about Optional in java8?

A - Optional is a container object which is used to contain not-null objects.

B - Optional object is used to represent null with absent value.

C - Both of the above.

D - None of the above.

Answer : C

Explanation

Both of the above options are correct.

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 operations do the iterations internally over the source elements provided.

A - false

B - true

Answer : B

Explanation

Stream operations do the iterations internally over the source elements provided, in contrast to Collections where explicit iteration is required.

Q 10 - In which of the following type of Base64 encoding, Output is mapped to MIME friendly format?

A - Simple

B - URL

C - MIME

D - None of the above.

Answer : C

Explanation

MIME − Output is mapped to MIME friendly format. Output is represented in lines of no more than 76 characters each, and uses a carriage return '' followed by a linefeed ' ' as the line separator. No line separator is present to the end of the encoded output.

java8_questions_answers.htm