A String is a sequence of characters like “Hello” or “123”. In Java, String is a class, not a primitive type, and it’s used to store text. 1. What is the String Pool in Java? The String Pool is a special area in memory where Java stores unique string literals. If you create two strings … Read more
A Hashtable in Java is a data structure that stores data in key-value pairs. It’s like a dictionary you use a key to find a value. Example: hashtable.put(“name”, “John”); Now you can get the value “John” by using the key “name”. Now, Why No Null Keys or Values? Java’s Hashtable does not allow null as … Read more
Before you can cook a meal, you need a kitchen with the right tools like a stove, a pot, and ingredients. Similarly, before you can write and run Java programs, you need to set up your Java development environment a few tools that help you write, check, and run your Java code. What Do You … Read more
Imagine you wrote a letter and made copies of it. Now you want people to read it but they all speak different languages. You’d need a translator for each one, right? Java works in a similar way! You write your code once, and Java takes care of the translation for each type of computer or … Read more
Java is a high-level, object-oriented, and general-purpose programming language used to build a wide range of applications from mobile apps and websites to games and enterprise software. It was created in 1995 by Sun Microsystems (now owned by Oracle). Java is known for being simple, secure, and fast — and most importantly, for working on … Read more
Let’s Start with a Simple Question: Have you ever given instructions to someone? Like: “Turn off the lights.” “Please bring me a glass of water.” “Open the door.” When you do that, you’re communicating with another person to make something happen. In the same way, a programming language is a special language we use to … Read more
A HashMap is a part of the Java Collections Framework and is used to store data in key-value pairs. It allows one null key and multiple null values, and it is not synchronized, making it faster but not thread-safe. A Hashtable is a legacy class in Java that also stores data in key-value pairs. It … Read more
An ArrayList in Java is a resizable array that can store a collection of elements. It allows you to add, remove, and access elements, and automatically adjusts its size as needed when elements are added or removed. Unlike regular arrays, you don’t need to specify the size in advance. It is a class in Java … Read more