Search Interview Questions
| 2720 questions in repository.|
There are more than 200 unanswered questions.
Click here and help us by providing the answer.
Have a video suggestion.
Click Correct / Improve and please let us know.
|Interview Questions and Answers for 'Optimus Information' - 1 question(s) found - Order By Newest|
|Advanced level question. Frequently asked in High end product companies. Frequently asked in Cognizant and Deloitte ( Based on 2 feedback )|
|Ans. 1. String Pool - When a string is created and if it exists in the pool, the reference of the existing string will be returned instead of creating a new object. If string is not immutable, changing the string with one reference will lead to the wrong value for the other references.|
String str1 = "String1";
String str2 = "String1"; // It doesn't create a new String and rather reuses the string literal from pool
// Now both str1 and str2 pointing to same string object in pool, changing str1 will change it for str2 too
2. To Cache its Hashcode - If string is not immutable, One can change its hashcode and hence it's not fit to be cached.
3. Security - String is widely used as parameter for many java classes, e.g. network connection, opening files, etc. Making it mutable might possess threats due to interception by the other code segment.
|Help us improve. Please let us know the company, where you were asked this question :|
|Like Discuss Correct / Improve java oops string string class immutable advanced Barclays Jungo Cloudera Allston Man Group Prokarma Optimus Gamesys ABS TransPerfect Fidelity Deloitte Zalando Cognizant (CTS) Zeta Interactive SuccessFactors EchoStar InterGlobe Technologies HCL Technologies Intuit JP Morgan Optimus Information Faichi Solutions Blip Adobe Subex Limited Remo Software Allstate IBM Bizmatics Bytecode Cyber Security Calsoft Systems IDS Infotech Nakisa expert   frequent|
Try 4 Question(s) Test
|How does making string as immutable helps with securing information ? How does String Pool pose a security threat ?|
|Why Char array is preferred over String for storing password?|
|How is string object immutable if we can concat a string to it ?|
|What is an Immutable Object ?|
|What is an immutable class ?|
|How to implement an immutable class ?|
|Does Declaring an object "final" makes it immutable ?|
|What are stateless objects ? How are they different from immutable objects ? Which of these two is thread safe ?|
|What are advantages of stateless and / or immutable objects ?|