Prepare Interview

Mock Exams

Make Homepage

Bookmark this page

Subscribe Email Address

Java 8 Interview Questions and Answers

Test your skills through the online practice test: Java 8 Quiz Online Practice Test

Related differences

Java 7 vs Java 8Java 8 vs Java 9

Ques 21. Provide some examples of Terminal operations.

Example of Terminal operations are:
  • forEach
  • toArray
  • reduce
  • collect
  • min
  • max
  • count
  • anyMatch
  • allMatch
  • noneMatch
  • findFirst
  • findAny

Is it helpful? Add Comment View Comments
 

Ques 22. Given the list of numbers, remove the duplicate elements from the list.

See the following code:

Integer[] arr=new Integer[]{1,2,3,4,3,2,4,2};
List<Integer> listWithDuplicates = Arrays.asList(arr);
Set<Integer> setWithoutDups = listWithDuplicates.stream().collect(Collectors.toSet());
setWithoutDups.forEach((i)->System.out.print(" "+i));

Is it helpful? Add Comment View Comments
 

Ques 23. Difference between Stream findFirst() and findAny().

  • findFirst will always return the first element from the stream whereas findAny is allowed to choose any element from the stream.
  • findFirst has deterministic behavior whereas findAny is nondeterministic behavior.

Is it helpful? Add Comment View Comments
 

Ques 24. What is consumer function interface?

It is a functional interface defined in java.util.function package. It contains an abstract accept() and a default andThen() method. It can be used as the assignment target for a lambda expression or method reference.
Consumer is single argument functional interface which does not return any value.

public static void main(String[] args) {  
   Consumer<String> consumerString = s->System.out.println(s);
   consumerString.accept("John");
}
 
We have created consumer object which takes String object as input and print it. It is simple use of Consumer interface to print String.
Output:
John

Is it helpful? Add Comment View Comments
 

Ques 25. What is predicate function interface?

Predicate is single argument function which returns true or false. It has test method which returns boolean. Usually, it used to apply in a filter for a collection of objects.

public static void main(String[] args) {
Predicate<Integer> predicate = i -> i > 100;
boolean greaterCheck = predicate.test(200);
System.out.println("is 200 greater than 100: "+greaterCheck);
}

Output:
is 200 greater than 100: true

Is it helpful? Add Comment View Comments
 

Most helpful rated by users:

©2024 WithoutBook