Search Interview Questions | More than 3000 questions in repository. There are more than 900 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 'ProKarma' - 6 question(s) found - Order By Rating | ||||
| ||||
Ans. A dirty read occurs when a transaction is allowed to read data from a row that has been modified by another running transaction but not yet committed. | ||||
Help us improve. Please let us know the company, where you were asked this question : | ||||
Like Discuss Correct / Improve  database transaction Asked in 8 Companies | ||||
Advanced level question. Frequently asked in High end product companies. Frequently asked in Google , 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. Example - 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  immutability   advanced Asked in 39 Companies expert   frequent | ||||
Try 4 Question(s) Test | ||||
| ||||
Ans. No, results in exception. | ||||
Help us improve. Please let us know the company, where you were asked this question : | ||||
Like Discuss Correct / Improve  java   collections   treemap Asked in 6 Companies Basic   frequent | ||||
| ||||
Ans. ConcurrentHashMap is a hashMap that allows concurrent modifications from multiple threads as there can be multiple locks on the same hashmap. | ||||
Help us improve. Please let us know the company, where you were asked this question : | ||||
Like Discuss Correct / Improve  java   collections   hashmap   map   concurrenthashmap   concurrenthashmap  concurrency   general electric   ge Asked in 32 Companies   rare | ||||
| ||||
Ans. Lazy fetching is the technique of not loading the child objects when parent objects are loaded. By default Hibernate does not load child objects. One can specify whether to load them or not while doing the association. | ||||
Help us improve. Please let us know the company, where you were asked this question : | ||||
Like Discuss Correct / Improve  hibernate   lazy fetching   architecture Asked in 11 Companies   frequent | ||||
Try 2 Question(s) Test | ||||
| ||||
Ans. This is the exception that is thrown when we try to modify the non concurrent collection class while iterating through it. | ||||
Help us improve. Please let us know the company, where you were asked this question : | ||||
Like Discuss Correct / Improve  java   collections   concurrentmodificationexception   exception  concurrency Asked in 14 Companies intermediate | ||||