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

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 …

Jul 1, 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: …

Apr 7, 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.

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 …

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? …

Sep 26, 2008 · if you are talking in terms of Java, both are collections which allow objects addition, deletion and updation and use Hasing algorithms internally. The significant difference however, if we …

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...

Aug 6, 2014 · HashMap in Java is a widely used data structure, which allows key-value pairs to be stored and retrieved in constant time. In this article, we will look into how the get () and put () …

Jul 7, 2009 · I need to convert a HashMap<String, Object> to an array; could anyone show me how it's done?