LinkedHashSet in Java: Order and Uniqueness Combined

Day 60 of Sharing What I’ve Learned 🚀 Comparable in Java — Defining Natural Sorting After learning how Comparator gives us custom sorting flexibility, I explored the foundation of sorting in Java — Comparable. 👉 Before customizing sorting… we should understand the default behavior 🔹 What is Comparable? Comparable is an interface in Java used to define natural (default) sorting of objects. 👉 It is implemented inside the class itself 🔹 How does Comparable work? 👉 We override compareTo() method 👉 Returns: ✔ Negative → current object comes before another ✔ Zero → both are equal ✔ Positive → current object comes after another 🔹 Why use Comparable? ✔ Defines default sorting behavior ✔ Simple and clean for single sorting logic ✔ Automatically used by sorting methods 🔹 Real-World Use Cases 👉 Sorting students by ID 👉 Sorting employees by name 👉 Sorting products by default price 🔹 Key Features ✔ Internal sorting logic (inside class) ✔ Only one sorting logic per class ✔ Works with Collections.sort() & Arrays.sort() 🔹 Comparable vs Comparator 👉 Comparable = internal / natural sorting 👉 Comparator = external / custom sorting 🔹 When should we use Comparable? 👉 Use it when: ✔ You need a single default sorting ✔ Sorting logic is fixed ✔ Natural ordering makes sense 🔹 When NOT to use? ❌ When multiple sorting logics are needed ❌ When sorting logic may change dynamically 🔹 Key Insight 💡 Before customizing everything… 👉 Always define a strong default behavior 🔹 Day 60 Realization 🎯 Great developers don’t just customize sorting… 👉 They design a meaningful default order first #Java #Comparable #DataStructures #CollectionsFramework #Programming #DeveloperJourney #100DaysOfCode #Day60 Grateful for guidance from, TAP Academy Sharath R kshitij kenganavar

Day 57 of Sharing What I’ve Learned🚀 PriorityQueue in Java — Processing Based on Priority After learning how TreeSet keeps elements sorted, I explored something even more practical — PriorityQueue. 👉 It doesn’t just store elements… it processes them based on priority 🔹 What is PriorityQueue? PriorityQueue is a part of the Java Collections Framework that stores elements in a way where the highest (or lowest) priority element is always processed first. 👉 It is internally based on a Heap (Min-Heap by default) 🔹 How does PriorityQueue work? 👉 Elements are not stored in full sorted order 👉 Only the head element is guaranteed to be the smallest (default) 👉 Insertion and removal maintain heap structure ✔ peek() → gives highest priority element ✔ poll() → removes highest priority element 🔹 Why use PriorityQueue? ✔ Priority-Based Processing Elements are handled based on importance, not insertion order ✔ Efficient Operations Insertion & deletion are faster than full sorting ✔ Real-World Use Cases 👉 Task scheduling 👉 CPU job scheduling 👉 Dijkstra’s Algorithm 👉 Event-driven systems 🔹 Key Features ✔ Allows duplicate elements ✔ Does NOT allow null values ✔ Not thread-safe ✔ Default is Min-Heap (smallest first) 🔹 Important Methods ✔ add() / offer() ✔ poll() ✔ peek() ✔ remove() 🔹 When should we use PriorityQueue? 👉 Use it when: ✔ You need to process elements by priority ✔ You don’t need full sorting ✔ You want efficient retrieval of min/max 🔹 When NOT to use? ❌ When you need full sorted traversal → use TreeSet ❌ When insertion order matters → use LinkedList/Queue ❌ When random access is required 🔹 Key Insight 💡 PriorityQueue doesn’t sort everything… 👉 It only guarantees the most important element comes first 🔹 Day 57 Realization 🎯 Not all problems need full sorting… 👉 Sometimes, knowing the “next most important” element is enough #Java #PriorityQueue #DataStructures #CollectionsFramework #Programming #DeveloperJourney #100DaysOfCode #Day57 Grateful for guidance from, Sharath R TAP Academy

🚀 Day-49 @ Tap Academy | Mastering ArrayDeque & TreeSet in Java Today’s learning was all about understanding two powerful components of the Java Collection Framework: ArrayDeque and TreeSet — both designed to solve different real-world problems efficiently. 🔹 ArrayDeque (Double-Ended Queue) ArrayDeque is a resizable array implementation of the Deque interface, which allows insertion and deletion from both ends. 👉 Key Features: Faster than Stack and LinkedList for queue operations No capacity restrictions (dynamic resizing) Does not allow null elements Can be used as both Stack (LIFO) and Queue (FIFO) 👉 Common Methods: addFirst(), addLast() removeFirst(), removeLast() peekFirst(), peekLast() 👉 Use Case: Efficient for scenarios like task scheduling, undo operations, or sliding window problems. 🔹 TreeSet (Sorted Set Implementation) TreeSet is a part of the SortedSet interface and is backed by a Red-Black Tree. 👉 Key Features: Stores unique elements only Maintains natural sorting order (ascending by default) Does not allow null elements Provides log(n) time complexity for basic operations 👉 Common Methods: add(), remove() first(), last() higher(), lower() 👉 Use Case: Ideal when you need sorted data without duplicates, like ranking systems or leaderboards. 💡 Key Difference: ArrayDeque → Focuses on fast insertion/removal from both ends TreeSet → Focuses on sorted, unique data storage ✨ Learning these concepts strengthens my understanding of how to choose the right data structure for optimized performance. 📌 What’s your go-to collection in Java for performance-critical applications? #Day49 #JavaLearning #TapAcademy #DataStructures #JavaCollections #CodingJourney #SoftwareDevelopment #LearningInPublic #Developers #Programming #TechCareers

Day 52 of Sharing What I’ve Learned 🚀 LinkedList in Java — Advantages & Disadvantages After exploring how LinkedList powers structures like Queue, I took a step back to understand something important — 👉 When should we actually use LinkedList, and when should we avoid it? 🔹 Advantages of LinkedList ✔ Dynamic Size No need to define size in advance — it grows and shrinks as needed. ✔ Efficient Insertions & Deletions Adding/removing elements is fast, especially at the beginning or middle. (No shifting like arrays!) ✔ Memory Utilization (Flexible Allocation) Memory is allocated as needed, not wasted upfront. ✔ Implements Multiple Structures Can be used as: ✔ List ✔ Queue ✔ Deque 🔹 Disadvantages of LinkedList ❌ More Memory Usage Each node stores extra references (pointers), increasing memory overhead. ❌ Slow Access (No Indexing) Unlike ArrayList, you can’t directly access elements — traversal is required. ❌ Poor Cache Performance Elements are not stored contiguously → slower compared to arrays. ❌ Not Ideal for Searching Searching is O(n), making it inefficient for large datasets. 🔹 LinkedList vs ArrayList (Quick Insight) 👉 Use LinkedList when: ✔ Frequent insertions/deletions ✔ Working with Queue/Deque 👉 Use ArrayList when: ✔ Fast access is needed ✔ More read operations than write 🔹 Key Insight 💡 Every data structure has trade-offs — 👉 The real skill is knowing when to use which one. 🔹 Day 52 Realization 🎯 Understanding limitations is just as important as learning features — That’s what makes you a better problem solver. #Java #LinkedList #DataStructures #CollectionsFramework #Programming #DeveloperJourney #100DaysOfCode #Day52 Grateful for guidance from, Sharath R TAP Academy

🚀 Day 47 of My Learning Journey – Java Wrapper Classes Today, I explored Wrapper Classes in Java, an important concept that bridges primitive data types and objects. 🔍 What I Learned: ✔️ Wrapper classes convert primitive data types into objects ✔️ Each primitive type has a corresponding wrapper class (e.g., int → Integer, char → Character, double → Double) ✔️ Enables use of primitives in collections like ArrayList 💡 Key Concepts: 🔹 Autoboxing – Automatic conversion of primitive to object 🔹 Unboxing – Converting object back to primitive 🔹 Useful methods like parseInt(), toString(), and valueOf() 📊 Why It Matters: Wrapper classes make Java more flexible by allowing primitives to be treated as objects, especially when working with frameworks and collections. 📌 Example Use Case: Storing integers in an ArrayList using Integer instead of int. 🎯 Takeaway: Understanding wrapper classes is essential for writing efficient and modern Java programs. #Java #LearningJourney #Programming #Day47 #TechSkills #Developers #Coding

🚀 Day 49 of My Learning Journey Today, I explored an important concept in Java — Creating Custom Immutable Classes 🔐 💡 An immutable object is one whose state cannot be changed after it is created. This concept is widely used in Java (like in String) and plays a key role in writing secure and thread-safe applications. 🔍 What I Learned: ✔ How to design my own immutable class ✔ Why immutability improves security and performance ✔ The importance of controlling object modification 🛠 Key Rules to Create Immutable Class: 🔹 Declare the class as final 🔹 Make all variables private and final 🔹 Initialize values through constructor 🔹 Do not provide setter methods 🔹 Return copies of mutable objects (defensive copying) 💻 Simple Example: final class Student { private final int id; private final String name; public Student(int id, String name) { this.id = id; this.name = name; } public int getId() { return id; } public String getName() { return name; } } 📌 Key Takeaway: Immutability helps in building safe, reliable, and predictable applications — especially in multi-threaded environments. 📈 Learning something new every day and getting one step closer to becoming a better developer! #Java #LearningJourney #Immutability #OOP #Programming #DeveloperGrowth

🚀 Core Java Learning Journey Explored Constructors in Java and the rules for writing them ☕ 🔹 What is a Constructor? A constructor is a special method used to initialize objects. It is automatically called when an object is created. 📌 Key Features of Constructors: ✅ Same name as the class ✅ No return type (not even "void") ✅ Automatically invoked during object creation ✅ Used to initialize instance variables 🔹 Types of Constructors: ✔️ Default Constructor ✔️ Parameterized Constructor 📌 Rules for Writing Constructors: 🔸 Constructor name must be the same as the class name 🔸 It should not have any return type 🔸 Can be overloaded (multiple constructors in one class) 🔸 Cannot be static, final, or abstract 🔸 If no constructor is written, Java provides a default constructor 💡 Example: class Student { int id; String name; Student(int i, String n) { // Parameterized constructor id = i; name = n; } } 🎯 Key Takeaway: Constructors make object initialization easy and are a fundamental part of Object-Oriented Programming in Java. Learning and growing at Dhee Coding Lab 💻 #Java #CoreJava #Constructors #OOP #Programming #LearningJourney #FullStackDevelopment

For the first time, Java didn’t feel like a “subject” I had to study — it felt like something I could actually understand. The way concepts were broken down, the depth, the clarity… it made me pause and think, why wasn’t this taught to us like this before? I ended up not just learning, but feeling connected to the topic. And that’s rare. So much so that I immediately tried explaining the same concepts in my own way to my audience — because when something finally clicks, you just want others to experience that too. Grateful to come across such teaching that doesn’t just focus on syntax, but on building intuition and confidence. Sometimes, all it takes is the right explanation to turn confusion into curiosity. 💭✨ heartfelt thanks to Aditya Tandon and Rohit Negi

While continuing my Java learning, I recently explored one of the most important concepts in programming — Methods. This helped me understand how to write cleaner, reusable, and more structured code. Here are some key learnings from this topic: ✨ Key Learnings – Java Methods • ⚙️ Methods – Blocks of code that perform a specific task and can be reused multiple times • 📥 Method Parameters – Inputs passed to a method, allowing dynamic and flexible execution • 📤 Return Values – Methods can return results using the "return" keyword, making them useful for computations • 🔁 Code Reusability – Methods help avoid repetition and make programs more organized • 🧩 Better Structure – Breaking programs into smaller methods improves readability and maintainability • 🔄 Recursion – A method calling itself to solve a problem step by step • 🎯 Base Condition in Recursion – Ensures the method stops at the right time and avoids infinite loop. #Java #Programming #LearningJourney #SoftwareDevelopment #StudentDeveloper #W3Schools

Day 41 of Learning JAVA! Today I learned about Java Optional (Null Handling + Streams Integration) 🔹 Why Optional? ✔ Problem: • Null → messy checks • High chance of NullPointerException ✔ Solution: • Optional = safe wrapper for value → Either: • value present • value absent (empty) 🔹 What is Optional? ✔ Acts like a container • One value → present • No value → empty ✔ Forces safer handling (no blind null usage) 🔹 Creating Optional • of() → value must exist • ofNullable() → handles null safely • empty() → no value 🔹 Safe Retrieval • isPresent() → check value • ifPresent() → run only if exists • get() → risky (can throw exception) 🔹 Default Handling • orElse() → fallback value • orElseGet() → fallback via function • orElseThrow() → throw custom exception 🔹 Transformations (Most Important) ✔ Functional style inside Optional • map() → transform value • flatMap() → avoid nested optionals • filter() → apply condition 🔹 Optional + Streams ✔ Works smoothly with streams • Handle missing values safely • Avoid null checks inside pipelines special thanks to Aditya Tandon Rohit Negi sir