No Java Interview will be completed without asking questions on Java Collection and questions on multithreading, these are most important topic in Java and you have to master these to clear Java interviews. collection interview questions are core part of any java interview. Collection interview consists question on various collection classes like hashset, hashmap, linkedhashmap, arraylist, vector, linkedlist, hashtable , treeMap, treeSet and ConncurrentHashMap. Now days questions are mainly difference between Concurrent Collection classes and synchronized collection classes which is tough to answer.
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