Core Java - Interview Questions and Answers for 'Nullpointerexception' | Search Java Interview Question

Core Java - Interview Questions and Answers for 'Nullpointerexception' - 5 question(s) found - Order By Newest

Q1. Is it ok to use optional everywhere just to get over nullpointerexception ?

^{2017-05-23 08:16:28}

Ans. Optional is to be used for arguments / atrributes which are indeed optional i.e the request should continue even if they aren't provided. It should not be used for mandatory attributes or arguments as we would like application to shout out ( with error message / exception trace ) to signify a problem.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve optional nullpointerexception java8 java 8 Asked in 1 Companies}

Q2. When does an application throw NullPointerException ?

Core Java

^{admin
info@buggybread.com}

Ans. When it tries to access an object element or method using reference which is actually null.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve exceptions npe nullpointerexception Asked in 1 Companies basic frequent}

Q3. How can we protect an application from throwing a NullPointerException ?

^{admin
info@buggybread.com}

Ans. By having Null Checks.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve exceptions npe nullpointerexception null checks basic frequent}

Q4. Doesn't it make sense to necessarily initialize references to some object to avoid NullPointerExceptions ? Can this be done ?

Core Java

^{2017-03-16 09:54:16}

Ans. We can declare the reference as final to avoid reassignment but again we can always initialize the final reference to null. Even if there was any such facility available , it would have meant poor use of resources by assigning a new object in memory to each reference that's created. Many a times references are just meant to refer to other objects which already have a reference i.e sharing object by multiple references.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve null NullPointerException}

Q5. Is it a bad practice to initialize object reference to Null ?

Core Java

^{2017-07-23 19:56:17}

^{This question is still unanswered. Can you please provide an answer.}

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve null nullpointerexception}

Q6. Which of the following is a valid way to avoid NullPointerException ?

Core Java

a. Avoid assigning null to the reference

b. Null Checks before accessing elements of an object

c. Both of the above

d. None of the above

Ans.b. Null Checks before accessing elements of an object

Search Interview Questions

Help us and Others Improve. Please let us know the questions asked in any of your previous interview.