The ordinary HashMap is NOT Thread-Safe, It can have one null key and multiple null values. And we can impleemnt a HashMap like example below: HashMap is non-Synchronized in nature i.e. HashMap is not ...

In order to use it, you've got to import java.util.HashMap, and you can create an instance just with HashMap, give it a variable name, equals new HashMap, and a couple of things. Notice I put a number ...

While the Hashtable was part of the initial Java release over two decades ago, the HashMap is the correct key-value store to use today. When Java 2 was released, the architects of the language ...