The Map interface abstracts what it means to be a map. Classes such as HashMap and java.util.TreeMap implement Map, describing different kinds of map implementations.

Do you need to know how to sort Java objects in a collection, array, or map? Here's how to use the Comparable and Comparator interfaces and avoid ClassCastExceptions.

HashMap vs. Hashtable similarities Both the Hashtable and HashMap implement the Map interface and both share the same set of methods used to add, remove and manipulate elements of a key-value, ...