Overriding toString() in Java: Importance and Best Practices

Revision | Day 6 – Multithreading Today I explored the basics of Multithreading in Java and why it is important for building high-performance applications. What is Multithreading? Multithreading allows a program to execute multiple threads (smaller units of a process) simultaneously. It helps improve application performance and better CPU utilization. Thread vs Runnable There are two main ways to create threads in Java: 1. Extending Thread class class MyThread extends Thread { public void run() { System.out.println("Thread is running"); } } 2. Implementing Runnable interface (recommended) class MyRunnable implements Runnable { public void run() { System.out.println("Thread is running"); } } Runnable is preferred because Java supports single inheritance but multiple interfaces. Synchronization When multiple threads access shared resources, it may cause inconsistent results. Synchronization ensures that only one thread accesses the critical section at a time. Example: synchronized void increment() { count++; } Deadlock Deadlock occurs when two or more threads wait for each other to release resources, causing the program to freeze. Example scenario: Thread 1 → lock1 → waiting for lock2   Thread 2 → lock2 → waiting for lock1 Both threads get stuck forever. Key takeaway: Understanding multithreading is essential for building scalable backend systems and handling concurrent requests efficiently. #Java #Multithreading #BackendDevelopment #JavaDeveloper #LearningInPublic

Today I Learned – Object Orientation Rules & Main Method in Java While learning Java, I explored how object relationships work and how a program starts execution. --> HAS-A Relationship Represents composition or aggregation, where one class contains another class object as a member. Example: Car HAS-A Engine --> DOES-A Relationship Represents behavior implementation, where a class performs behavior defined by another type using interfaces or abstract classes. Example: Bird DOES-A Flyable --> Main Method in Java The entry point of a Java application where the Java Virtual Machine starts program execution. Syntax: public static void main(String[] args) Breakdown: • public → Accessible everywhere • static → Can be executed without creating an object • void → Does not return a value • main → Method recognized by JVM to start execution • String[] args → Used to receive command-line arguments #JavaDeveloper #ObjectOrientedProgramming #OOP #JavaLearning #BackendDevelopment #CodingJourney #100DaysOfCode #LearningInPublic #DeveloperCommunity #FutureDeveloper #TechCareer

🚀 Understanding Multi-Dimensional Jagged Arrays in Java In today’s Core Java session, I explored the concept of Multi-Dimensional Jagged Arrays and their internal memory representation in JVM. This visualization helped me understand how jagged arrays differ from regular multi-dimensional arrays, where each row can have a different number of elements. I also learned how memory is dynamically allocated and how references point to different array objects inside the JVM. 🔍 Key Learnings: • Structure of multi-dimensional jagged arrays • JVM internal memory allocation and reference handling • Difference between regular arrays and jagged arrays • Dynamic memory allocation using the new keyword • Visualization of array hierarchy and dimensionality 💡 This session strengthened my understanding of Java memory management, JVM architecture, and advanced array concepts, which are essential for building efficient and scalable applications. Thanks to Sharath R for the valuable guidance and practical explanation of jagged arrays in Java. 📌 Continuously improving my Core Java and problem-solving skills. #Java #CoreJava #JVM #JaggedArray #Programming #JavaDeveloper #LearningJourney #SoftwareDevelopment #TapAcademy

📘 Abstract Class vs Interface in Java — Key Differences Today I explored one of the most important OOP concepts in Java: the difference between Abstract Classes and Interfaces. Both are used to achieve abstraction, but they serve different design purposes in Java applications. 🔹 Abstract Class • Supports partial abstraction • Can contain both abstract and concrete methods • Allows instance variables and constructors • Supports single inheritance using extends 🔹 Interface • Used for full abstraction (mostly) • Methods are public and abstract by default • Variables are public static final • Supports multiple inheritance using implements 💡 Key takeaway: Abstract classes are used when classes share common behavior, while interfaces define a contract that multiple unrelated classes can implement. Understanding when to use each helps in writing clean, scalable, and maintainable Java code. A special thanks to my mentor kshitij kenganavar sir for clearly explaining the concepts of Abstract Classes and Interfaces in Java. #Java #OOP #JavaProgramming #AbstractClass #Interface #SoftwareDevelopm

🚀 Today I Learned – Java Static in Inheritance & Object Class Today I strengthened my understanding of some important Java concepts: 🔹 Static Variable Inheritance Static variables are inherited, but only one shared copy exists across the entire class hierarchy. 🔹 Static Methods & Method Hiding Static methods are inherited, but they cannot be overridden — they are hidden based on the reference type. 🔹 Execution Order in Inheritance Understanding the flow is important: Static Block → Instance Block → Parent Constructor → Child Constructor 🔹 Object Class as Root Every class in Java automatically inherits from the Object class. 🔹 Default vs Custom toString() By default, toString() returns: ClassName@Hashcode But we can override it to return meaningful and readable output. ✨ Small concepts, but very important for writing clean and predictable Java programs. TAP Academy #Java #OOP #Programming #LearningJourney #ComputerScience #JavaDeveloper #TapAcademy

instanceof on primitives sounds almost illegal in classic Java. Developers were taught for 20+ years that primitives and instanceof don’t mix. Java is now carefully breaking that rule. What actually changes with this feature, and why does it matter? Manoj Nalledathu Palat, one of our Open Community Experience speakers on the Main Track, will explain why that mental model made sense historically, and why Java is now expanding how instanceof is interpreted as pattern matching becomes more central to the language. This isn’t about new syntax to rush into production. It’s about understanding how Java’s type system is evolving, from the perspective of someone implementing it in the compiler. 🎟️ Attend this talk live at OCX to learn more: https://hubs.la/Q0449rsf0 #java #javacompiler #opensource

Threads state & Priority in java 🧵 After understanding what thread is and how to create one, the next question is: ➡️What state my thread is and how does the JVM schedule it? 🧠Threads States in Java A thread can be in one of these states during its lifecycle: 🔸NEW Thread is created but not yet started (start() method is not called) 🔸RUNNABLE Thread is ready to run or concurrently running 🔸BLOCKED Waiting to acquire a monitor lock (synchronized block) 🔸 WAITING Waiting indefinitely for another thread to act 🔸TIMED_WAITING Waiting for a specified time( sleep(), wait(timeout), join(timeout) ) 🔸TERMINATED Execution completed 👉A thread doesn't move linearly - it can jump between states multiple times. ---------------------------------------------------------------------- ⚡Thread Priority in Java Each thread has a priority that hints the scheduler: ✓MIN_PRIORITY — 1 ✓NORM_PRIORITY — 5(default) ✓MAX_PRIORITY — 10 ☘️Example: Thread t = new Thread(task); t.setPriority(Thread.MAX_PRIORITY); IMPORTANT ⚠️ 1.Priority is a hint, not a guarantee. 2.Behaviour is OS and JVM dependent. 3.High priority doesn't mean it will always run first. #Java #Threads #Concurrency #Multithreading #SoftwareEngineering #Backend #Programming

Understanding the main() Method in Java Every Java program begins execution from a single entry point — the main() method. Understanding its structure is fundamental for anyone starting with Java. public static void main(String[] args) Let’s break it down clearly: public → Access specifier. The JVM must access this method from anywhere. static → Allows the method to be called without creating an object of the class. void → Specifies that the method does not return any value. main → The method name recognized by the JVM as the starting point. String[] args → Command-line arguments passed during program execution. Function Body { } → The block where execution actually begins. If the signature is modified incorrectly, the JVM will not recognize it as the entry point. Understanding this is not just about syntax — it’s about understanding how the JVM interacts with your program. Grateful to my mentor Anand Kumar Buddarapu for emphasizing the importance of fundamentals and ensuring I build a strong base before moving to advanced concepts. Your guidance truly makes a difference. #Java #Programming #CoreJava #LearningJourney #SoftwareDevelopment

Monday Deep Dive – Java Strings Complete Revision Today I revisited one of the most important topics in Core Java: 🔹 String & String Constant Pool 🔹 Immutability & Memory Management 🔹 String Comparison Techniques 🔹 Concatenation Methods & Performance Tests 🔹 substring(), split(), indexOf() 🔹 String vs StringBuffer vs StringBuilder 🔹 Immutable Class Design 🔹 toString() Method 🔹 StringTokenizer (Legacy vs Modern Approach) Understanding how Strings work internally is crucial for writing efficient, optimized, and interview-ready Java code. Strong fundamentals. Clean code. Better performance. 🚀 #Java #CoreJava #JavaDeveloper #DSA #StringConcepts #Coding #LearningJourney #CodesInTransit #InterviewPreparation #MondayMotivation #RevisitingTheTopics