Java Priority Queue Implementation and Usage

🚀 Core Java Learning Journey Explored Instance, Static, and Local Variables in Java ☕ 🔹 Local Variables - Declared inside methods, constructors, or blocks - Accessible only within that specific scope - Must be initialized before use - Stored in stack memory 🔹 Instance Variables - Declared inside a class but outside methods - Belong to each object of the class - Each object has its own copy - Stored in heap memory 🔹 Static Variables - Declared using the "static" keyword - Shared among all objects of the class - Only one copy exists - Stored in method area 💡 Example: class Demo { int instanceVar = 10; // Instance variable static int staticVar = 20; // Static variable void display() { int localVar = 5; // Local variable System.out.println(localVar); } } 🎯 Key Takeaway: Understanding variable types helps in writing efficient and optimized Java programs by managing memory and scope effectively. Learning and growing at Dhee Coding Lab 💻 #Java #CoreJava #Variables #OOP #Programming #LearningJourney #FullStackDevelopment

🚀 Core Java Learning Journey Explored Variables in Java ☕ 🔹 What is a Variable? A variable is a container used to store data values in a program. Each variable has a name, type, and value. 📌 Types of Variables in Java: ✅ Local Variables - Declared inside methods, constructors, or blocks - Accessible only within that scope - Must be initialized before use ✅ Instance Variables - Declared inside a class but outside methods - Belong to objects - Each object has its own copy ✅ Static Variables - Declared using "static" keyword - Shared among all objects of the class - Memory allocated only once 💡 Example: "int age = 21;" "String name = "Java";" 🎯 Key Takeaway: Variables are the basic building blocks of any Java program used to store and manage data efficiently. Learning and growing at Dhee Coding Lab 💻 #Java #CoreJava #Variables #Programming #LearningJourney #FullStackDevelopment

🚀 Core Java Learning Journey Explored How to Write Package Statement in Java ☕ 🔹 What is a Package Statement? A package statement is used to define the package (namespace) in which a class belongs. It helps organize classes into a structured hierarchy. 📌 Syntax of Package Statement: package package_name; 👉 It must be the first statement in a Java file (before any import or class declaration). --- 📌 Example: package com.myapp; public class Demo { public static void main(String[] args) { System.out.println("Hello Package"); } } --- 📌 Key Rules: ✅ Package statement should be written at the top of the file ✅ Only one package statement is allowed per file ✅ Package name should follow naming conventions (lowercase, reverse domain like "com.company") --- 📌 Compile & Run: javac -d . Demo.java java com.myapp.Demo --- 🎯 Key Takeaway: The package statement defines the location of a class and helps in organizing Java programs into a clean and maintainable structure. Learning and growing at Dhee Coding Lab 💻 #Java #CoreJava #Packages #Programming #LearningJourney #FullStackDevelopment

🚀 Core Java Learning Journey Explored the "this" keyword in Java ☕ 🔹 What is "this" keyword? "this" is a reference variable that refers to the current object of a class. It is used to access instance variables and methods of the current object. 📌 Uses of "this" keyword: ✅ 1. To refer instance variables - Used when local variables or parameters have the same name (avoids shadowing) class Student { int id; Student(int id) { this.id = id; } } --- ✅ 2. To call current class methods void display() { this.show(); } --- ✅ 3. To invoke current class constructor Student() { this(100, "Java"); } --- ✅ 4. To pass current object as argument method(this); --- 🎯 Key Takeaway: "this" keyword helps in clearly referring to the current object and avoids confusion between instance and local variables. Learning and growing at Dhee Coding Lab 💻 #Java #CoreJava #ThisKeyword #OOP #Programming #LearningJourney #FullStackDevelopment

🚀 Understanding TreeSet in Java – Clean, Sorted & Powerful! While working with Java Collections, I explored TreeSet, a powerful implementation of the Set interface that ensures data is always sorted and unique. Here are some key insights I learned: 🔹 Sorted Order TreeSet automatically stores elements in ascending sorted order, making it ideal when ordering is important. 🔹 Traversal Mechanism It internally follows Inorder Traversal (LVR), which is why elements remain sorted. 🔹 Data Type TreeSet stores only homogeneous data, as elements must be mutually comparable. 🔹 No Duplicates Allowed Being a Set, it does not allow duplicate values. 🔹 No Null Values TreeSet does not allow null, as it relies on comparison logic. 🔹 Insertion Order Not Preserved Unlike some collections, it does not maintain insertion order. 🔹 Initial Capacity TreeSet does not define an initial capacity (internally managed). 🔹 Constructors TreeSet provides 5 different constructors for flexibility. 🔹 Internal Data Structure It is based on a Binary Search Tree (BST) (specifically a self-balancing tree like Red-Black Tree). 💡 Accessing Elements in TreeSet Since TreeSet does not support indexing, we use: ✔️ For-each loop ✔️ Iterator ✔️ Descending Iterator ❌ Not supported: Traditional for loop (index-based) ListIterator 🎯 When to Use TreeSet? Use TreeSet when you need: ✔️ Sorted data ✔️ Unique elements ✔️ Efficient searching and retrieval 📌 Mastering collections like TreeSet helps in writing cleaner and more efficient Java programs. #Java #CollectionsFramework #TreeSet #Programming #JavaDeveloper #LearningJourney TAP Academy

Polymorphism in Java Polymorphism is one of the core concepts of Object-Oriented Programming (OOP). It allows a single method name to perform different tasks based on the input. Types of Polymorphism in Java: 1. Compile-Time Polymorphism (Static Binding)→ Achieved using Method Overloading. 2. Run-Time Polymorphism (Dynamic Binding)→ Achieved using Method Overriding. Today I Learned: 1. Compile-Time Polymorphism in Java Today I explored the concept of Compile-Time Polymorphism, also known as Method Overloading in Java. It allows a class to have multiple methods with the same name but different parameters (type, number, or order). The method call is resolved at compile time, which makes the execution faster and more efficient. Example: Calculator using Method Overloading. This concept improves code readability and helps in writing flexible and reusable code. #Java #OOP #Polymorphism #MethodOverloading #LearningJourney

🚀 Core Java Learning Journey Explored Ways to Initialize an Object in Java ☕ 🔹 Object initialization means assigning values to the instance variables of an object. 📌 Ways to Initialize an Object: ✅ 1. Using Reference Variable - Values are assigned after object creation class Student { int id; String name; } Student s = new Student(); s.id = 101; s.name = "Java"; --- ✅ 2. Using Method - Values are initialized using a method class Student { int id; String name; void setData(int i, String n) { id = i; name = n; } } --- ✅ 3. Using Constructor - Values are assigned at the time of object creation class Student { int id; String name; Student(int i, String n) { id = i; name = n; } } --- 🎯 Key Takeaway: Objects can be initialized in multiple ways, but using constructors is the most efficient and commonly used approach. Learning and growing at Dhee Coding Lab 💻 #Java #CoreJava #OOP #Constructors #Programming #LearningJourney #FullStackDevelopment

🚀 Java Collections Framework & ArrayList – Simple Notes While learning Java, I explored the Collections Framework and understood how it helps in storing and managing data efficiently. 🔹 What is Collections Framework? It is a group of classes and interfaces used to store, manipulate, and process data easily. 🔹 Why it was introduced? Earlier, we used arrays which had many limitations (fixed size, difficult operations). To overcome this, Java introduced Collections. 📌 Common Interfaces & Classes - List → ArrayList, LinkedList - Set → HashSet, TreeSet - Queue → Deque - Map → HashMap 💡 What is ArrayList? - A resizable (dynamic) array - Stores objects (not primitive data types) - Allows duplicate values - Maintains insertion order - Allows null values ⚙️ Constructors of ArrayList - "ArrayList()" → default - "ArrayList(int capacity)" → with initial size - "ArrayList(Collection c)" → from another collection 📈 Capacity Concept - Default capacity = 10 - When full, it increases using: 👉 "(current size × 3/2) + 1" 🔁 Ways to Access Elements 1. For loop 2. For-each loop 3. Iterator (forward only) 4. ListIterator (forward & backward) 🛠️ Important Methods - "add()" → add element - "add(index, value)" → add at position - "get()" → access element - "set()" → update value - "remove()" → delete element - "size()" → number of elements - "isEmpty()" → check empty or not - "contains()" → check element - "indexOf()" / "lastIndexOf()" → find position - "clear()" → remove all - "subList()" → get part of list - "trimToSize()" → reduce memory 📌 When to Use ArrayList? ✔ When you need dynamic size ✔ When duplicates are allowed ✔ When order matters ✔ When frequent read operations are needed ✨ In short: ArrayList makes data handling easy, flexible, and efficient compared to traditional arrays. #Java #Collections #ArrayList #Programming #Learning #CodingJourney

Day 58/200 - Java Learning Journey 🌱 ✨ Sharing what I learned today in Java. 📚 Today I learned about Encapsulation in Java Today's Topic: Encapsulation ✴️ Encapsulation: 👉 It means wrapping(hiding) the data (variables,methods) and providing the controlled access. 🔯 Advantages/Features: 🔺 Security 🔺 Hiding the data 🔺 Controlled access 🔺 Validation 🔺 Flexibility 🔆 How to hide the data ❓ ▪️ By making those variables,methods to be private. 1️⃣ Setters: 👉 These are used to set the data. 2️⃣ Getters: 👉 Get or return the data. 🔸 Syntax: For setters: access_modifier returntype(void) settersName(){ -------------//data } For getters: access_modifier returntype gettersName(){ return value; } 💠 Without setters we cant use getters. 💠 Without getters we can set the value by using setters. 👎 Drawback: 👉 In Encapsulation for each and every variables we need to use setters to set the value to those variables. #Java#Encapsulation#OOPS#DailyLearning#Consistency#Meghana M#10000 Coders#

🚀 Learning Core Java – Understanding Access Modifiers Today I explored an important concept in Java — Access Modifiers. Access modifiers define the visibility and accessibility of classes, variables, methods, and constructors. They help in achieving encapsulation and data security. In Java, there are four types of access modifiers: ⸻ 🔹 1️⃣ Public ✔ Accessible from anywhere (within the same package and from other packages) ✔ No restrictions on access ⸻ 🔹 2️⃣ Protected ✔ Accessible within the same package ✔ Also accessible in subclasses (child classes) from other packages ⸻ 🔹 3️⃣ Default (Package-Level) ✔ No keyword is used (also called package-private) ✔ Accessible only within the same package ⸻ 🔹 4️⃣ Private ✔ Accessible only within the same class ✔ Cannot be accessed outside the class 💡 Key Insight Access modifiers help in: ✔ Controlling access ✔ Improving security ✔ Maintaining clean architecture Choosing the right access level is crucial for writing secure and maintainable Java applications. Excited to keep strengthening my Java fundamentals! 🚀 #CoreJava #AccessModifiers #JavaProgramming #Encapsulation #ObjectOrientedProgramming #JavaDeveloper #ProgrammingFundamentals #LearningJourney