7 Apr 2010 · Hashmap is used for storing data in key value pairs. We can use a hashmap for storing objects in a application and use it further in the same application for storing, updating, deleting values.

What are the differences between a HashMap and a Hashtable in Java? Which is more efficient for non-threaded applications?

64 Map is an interface that HashMap implements. The difference is that in the second implementation your reference to the HashMap will only allow the use of functions defined in the Map interface, while …

1 Jul 2009 · Since all maps in Java implement the Map interface, the following techniques will work for any map implementation (HashMap, TreeMap, LinkedHashMap, Hashtable, etc.) Method #1: …

Apart from the fact that HashSet does not allow duplicate values, what is the difference between HashMap and HashSet in their implementation? It's a little bit vague because both use hash tables to...

Map<String, String> myMap = new HashMap<String, String>() {{ put("a", "b"); put("c", "d"); }}; However, the anonymous subclass might introduce unwanted behavior in some cases. This includes for …

I want to implement a HashMap in Python. I want to ask a user for an input. depending on his input I am retrieving some information from the HashMap. If the user enters a key of the HashMap, I wo...

What is the difference between HashMap, LinkedHashMap and TreeMap in Java? I don't see any difference in the output as all the three has keySet and values. Also, what are Hashtables? …

805 Suppose we have a HashMap<String, Integer> in Java. How do I update (increment) the integer-value of the string-key for each existence of the string I find? One could remove and reenter the pair, …

6 Sep 2009 · If I have the value "foo", and a HashMap<String> ftw for which ftw.containsValue("foo") returns true, how can I get the corresponding key? Do I have to loop through the hashmap? What is …