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