Explain about HashMap? What are the differences between HashMap and Hashtable? 42. Several new Collection classes are added in Java 5 and Java 6 specially concurrent alternatives of standard synchronized ArrayList, HashTable and synchronized HashMap … 44. Hashmap is traversed using an iterator, hashtable can be traversed by enumerator or iterator. 40. 43. We use put() method to insert the Key and Value pair in the HashMap. 46. Comparable and Comparator both are interfaces and can be used to sort collection elements. Difference between HashMap and Hashtable is one of the most popular java interview questions. How do I efficiently iterate over each entry in a Java Map? However, there are many differences between Comparable and Comparator interfaces that are given below. The default size of HashMap is 16 (0 to 15). Example. 21) Difference between Vector and ArrayList? . 224) Difference between arraylist and linkedlist? In the following example, we want to insert three (Key, Value) pair in the HashMap. But, the methods of ArrayList is not synchronized. 47. 223) Difference between HashMap and Hashtable? How do I read / convert an InputStream into a String in Java? What is difference between HashSet and TreeSet? What is Entry interface? Difference between Comparable and Comparator. ... durga sir ameerpet Harikrishna Sir Ameerpet JAVA IN HINDI Java Introduction Object oriented Programming In Hindi Popular Posts Identifiers Of Java In HINDI Language - NIMAJAVA. 4241. By Sonu Kumar Ray Page 1 Q:Difference between HashMap and HashTable? 45. The third significant difference between HashMap vs Hashtable is that Iterator in the HashMap is a fail-fast iterator while the enumerator for the Hashtable is not. 41. HashMap permits null values and only one null key, while Hashtable doesn't allow key or value as null. 47. How do I generate random integers within a specific range in Java? 654. 34) What is the purpose of Map interface? 3466. What are the differences between HashMap and LinkedHashMap? What is Entry interface? Explain about LinkedHashMap? 40. Insert Key, Value pair in HashMap. 35) What do you mean by entry. Lets note down the differences: All the methods of Vector is synchronized. What is difference between HashSet and TreeSet? 36) What is the difference between HashMap & LinkedHashMap? 38) What is the difference between TreeSet andTtreeMap? 42. What are differences between Comparable and Comparator? Iterator in hashmap and hashtable is fail fast but enumerator in hashtable isfail safe. Explain about LinkedHashMap? What are the differences between a HashMap and a Hashtable in Java? What are the differences between HashMap and LinkedHashMap? 41. What are differences between Comparable and Comparator? 43. (HashMap allows null values as key and value whereas Hashtable doesnt allow). What are the differences between HashMap and Hashtable? Explain about HashMap? 3647. 46. 45. 225) Difference between Comparator and Comparable in java? A: The HashMap class is roughly equivalent to Hashtable, except that it is unsynchronized and permits nulls. 39) What is the difference between HashTable and Properties file key=value pairs? 44. 37) What is the difference between comparable vs Comparator interface? We have already discussed other popular java interview questions like ArrayList vs Vector and Comparator vs Comparable.This question is generally asked in java intereview to check whether candidate understand correct usage of collection classes and has knowledge of alternative solutions. Between Comparator and comparable in Java in HashMap and Hashtable is one difference between hashmap and hashtable by durga... 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