Collections in Java

What is Collections Framework in Java? The Java Collections Framework (JCF) is a set of classes and interfaces provided by Java to store, manage, and manipulate groups of objects efficiently. Before Collections, developers mainly used arrays. Arrays have a fixed size and limited functionality. Collections provide dynamic storage and many built-in methods for handling data. Package: java.util Why is Collections Used? Collections are used to: Store multiple objects dynamically. Perform searching, sorting, insertion, and deletion easily. Reduce coding effort through built-in methods. Improve code reusability and maintainability. Handle large amounts of data efficiently. Without Collections int[] arr = new int[100]; Fixed size Difficult to resize Limited operations With Collections ArrayList<Integer> list = new ArrayList<>(); Dynamic size Easy insertion and deletion Rich utility methods Advantages Dynamic Size Ready-Made Data Structures Better