Mar 7, 2025 · In Java, HashMap is part of the Java Collections Framework and is found in the java.util package. It provides the basic implementation of the Map interface in Java. HashMap stores data in (key, value) pairs. Each key is associated with a value, and you can access the value by using the corresponding key.

Create a HashMap object called capitalCities that will store String keys and String values: import java.util.HashMap; // import the HashMap class HashMap<String, String> capitalCities = new HashMap<String, String>();

Jan 16, 2025 · In this tutorial, we’ll see how to use HashMap in Java, and we’ll look at how it works internally. A class very similar to HashMap is Hashtable. Please refer to a couple of our other articles to learn more about the java.util.Hashtable class itself and the differences between HashMap and Hashtable. 2. Basic Usage

The HashMap class provides the functionality of the hash table data structure in Java. In this tutorial, we will learn about the Java HashMap class and its various operations with the help of examples.

Dec 14, 2015 · 1) Explain the different ways of creating HashMap in java? Below example shows 4 different methods for creating HashMap. 2) How do you add key-value pairs to HashMap? …

Dec 5, 2024 · The HashMap, part of the Java Collections framework, is used to store key-value pairs for quick and efficient storage and retrieval operations. In the key-value pair (also referred to as an entry) to be stored in HashMap, the key must …

Jan 18, 2024 · HashMap is a data structure that implements the Map interface and uses a hash table for storing key-value pairs. It allows the insertion of elements based on key-value pairs and provides constant-time performance for basic operations like adding or retrieving elements.

Nov 22, 2021 · In this tutorial, We'll be learning HashMap API and its usage. HashMap is one of the implementations of the Map interface. HashMap is widely used in the realtime applications …

Sep 19, 2022 · HashMap is a Map based collection class that is used for storing Key & value pairs, it is denoted as HashMap<Key, Value> or HashMap<K, V>. HashMap in java, is similar to the Hashtable class except that it is unsynchronized and permits nulls (null values and null key).

Mar 21, 2025 · By the end of this article, you'll have a solid understanding of how to use HashMap in Java, including how to create, manipulate, and optimize it for your needs. So, let's get started! What is a HashMap? A HashMap is a part of Java’s collection framework and is based on the hashing technique.