JAVA DSA Implementations

This repository is a collection of Java implementations for core data structures, algorithms, and recursion exercises.

Included Implementions :

1 - Algorithms

Sorting algorithm implementations with standalone demo programs.

• Bubble_Sort.java - bubble sort
• Insertion_Sort.java - insertion sort
• Quick_Sort.java - quick sort
• Selection_Sort.java - selection sort

2 - ArrayOfObjects

Practice code for working with Java objects and a linked-list implementation located under src/LinkedList/.

• Main.java - IntelliJ starter class
• src/LinkedList/LinkedList.java - linked list implementation
• src/LinkedList/Node.java - node definition
• src/LinkedList/oopLinkedList.java - object-oriented linked list example

3 - ArrayQueueProject

Fixed-size queue implemented with an array.

• ArrayQueue.java - array-backed queue implementation
• Main.java - demo entry point

4 - ArrayStackProject

Fixed-size stack implemented with an array.

• ArrayStack.java - array-backed stack implementation
• Main.java - demo entry point

5 - BinarySearchTree

Binary search tree implementation with insertion and traversal support.

• BST.java - tree operations
• TreeNode.java - node structure
• Main.java - demo entry point

6 - CustomArrayList

Generic dynamic array implementation.

• ArrayList.java - custom generic list
• Main.java - demo entry point
• test.java - supporting test file

7 - CustomCircularLinkedList

Circular singly linked list implementation.

• CircularLinkedList.java - list operations
• CircularNode.java - node structure
• Main.java - demo entry point

8 - CustomDoublyLinkedList

Doubly linked list implementation with forward and backward links.

• DoublyLinkedList.java - list operations
• DoublyNode.java - node structure
• Main.java - demo entry point

9 - CustomLinkedList

Singly linked list implementation with insertion, deletion, and display operations.

• LinkedList.java - list operations
• Node.java - node structure
• Main.java - demo entry point

10 - LinkedListQueueProject

Queue implemented with linked nodes.

• Queue.java - queue operations
• QueueNode.java - node structure
• Main.java - demo entry point

11 - LinkedListStackProject

Stack implemented with linked nodes.

• Stack.java - stack operations
• StackNode.java - node structure
• Main.java - demo entry point

12 - Recursions

Recursive function examples.

• Main.java - recursion demos such as sum, factorial, and Fibonacci

Project structure

JAVA-DSA-PROJECTS/
├── Algorithms/
├── ArrayOfObjects/
├── ArrayQueueProject/
├── ArrayStackProject/
├── BinarySearchTree/
├── CustomArrayList/
├── CustomCircularLinkedList/
├── CustomDoublyLinkedList/
├── CustomLinkedList/
├── LinkedListQueueProject/
├── LinkedListStackProject/
└── Recursions/

Each project keeps its code inside src/, and most folders include a Main.java file for quick execution from the IDE.

Contributing

Contributions are welcome. Supported contribution types:

• Bug fixes
• New algorithms and data structure implementations
• Code improvements and refactoring
• Documentation and examples
• Additional test cases

To contribute, fork the repository, make your changes on a feature branch, and submit a pull request with a clear description of the changes.

Author : Shehan Sulakshana