Java Operators

Java Control Statements

Object Oriented Programming

Java Built-in Classes

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 System.out::println expression?

A - System.out::println method is a static method reference to println method of out object of System class.

B - System.out::println method is a instance method reference to println method of out object of System class.

C - Both of the above.

D - None of the above.

Answer : A

Explanation

System.out::println method is a static method reference to println method of out object of System class.

Q 2 - Which of the following functional interface represents a predicate (Boolean-valued function) of two arguments?

A - BiConsumer<T,U>

B - BiFunction<T,U,R>

C - BinaryOperator<T>

D - BiPredicate<T,U>

Answer : D

Explanation

BiPredicate<T,U> functional interface represents a predicate (Boolean-valued function) of two arguments.

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

A - DoubleToLongFunction

B - DoubleUnaryOperator

C - Function<T,R>

D - IntBinaryOperator

Answer : A

Explanation

DoubleToLongFunction functional interface represents a function that accepts a double-valued argument and produces a long-valued result.

Q 4 - Which of the following functional interface represents an operation that accepts a single long-valued argument and returns no result?

Answer : A

Explanation

LongConsumer functional interface represents an operation that accepts a single long-valued argument and returns no 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 - Which of the following is correct about streams in java8?

A - Stream represents a sequence of objects from a source, which supports aggregate operations.

B - Most of the stream operations return stream itself so that their result can be pipelined.

C - Both of the above.

D - None of the above.

Answer : C

Explanation

Both of the above options are correct.

Q 7 - Can you execute javascript code from java 8 code base?

A - true

B - false

Answer : A

Explanation

Yes! Using ScriptEngineManager, JavaScript code can be called and interpreted in Java.

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 - Most of the stream operations return stream itself so that their result can be pipelined.

A - false

B - true

Answer : B

Explanation

Most of the stream operations return stream itself so that their result can be pipelined.

Q 10 - Optional.isPresent method checks the value is present or not.

A - false

B - true

Answer : B

Explanation

Optional.isPresent method checks the value is present or not.

java8_questions_answers.htm