Want to get started with System design interview preparation, start with these 👇

1. Learn to understand requirements
2. Learn the difference between horizontal and vertical scaling.
3. Study latency and throughput trade-offs and optimization techniques.
4. Understand the CAP Theorem (Consistency, Availability, Partition Tolerance).
5. Learn HTTP/HTTPS protocols, request-response lifecycle, and headers.
6. Understand DNS and how domain resolution works.
7. Study load balancers, their types (Layer 4 and Layer 7), and algorithms.
8. Learn about CDNs, their use cases, and caching strategies.
9. Understand SQL databases (ACID properties, normalization) and NoSQL types (key–value, document, graph).
10. Study caching tools (Redis, Memcached) and strategies (write-through, write-back, eviction policies).
11. Learn about blob storage systems like S3 or Google Cloud Storage.
12. Study sharding and horizontal partitioning of databases.
13. Understand replication (leader–follower, multi-leader) and consistency models.
14. Learn failover mechanisms like active-passive and active-active setups.
15. Study message queues like RabbitMQ, Kafka, and SQS.
16. Understand consensus algorithms such as Paxos and Raft.
17. Learn event-driven architectures, Pub/Sub models, and event sourcing.
18. Study distributed transactions (two-phase commit, sagas).
19. Learn rate-limiting techniques (token bucket, leaky bucket algorithms).
20. Study API design principles for REST, GraphQL, and gRPC.
21. Understand microservices architecture, communication, and trade-offs with monoliths.
22. Learn authentication and authorization methods (OAuth, JWT, SSO).
23. Study metrics collection tools like Prometheus or Datadog.
24. Understand logging systems (e.g., ELK stack) and tracing tools (OpenTelemetry, Jaeger).
25.Learn about encryption (data at rest and in transit) and rate-limiting for security.
26. And then practise the most commonly asked questions like URL shorteners, chat systems, ride-sharing apps, search engines, video streaming, and e-commerce websites

Coding Interview Resources: https://whatsapp.com/channel/0029VammZijATRSlLxywEC3X

☕ Java Roadmap

1️⃣ Basics: 🔤📜 Syntax, Variables, Data Types
2️⃣ OOP Concepts: 🏛️🔄 Classes, Objects, Inheritance, Polymorphism
3️⃣ Exception Handling: ⚠️🛠️ Try-Catch, Custom Exceptions
4️⃣ Collections Framework: 📚🗂️ Lists, Sets, Maps
5️⃣ Multithreading: ⏳🔄 Threads, Synchronization
6️⃣ File Handling: 📄📂 Read/Write Files, Serialization
7️⃣ Java 8+ Features: 🎯📜 Streams, Lambda Expressions, Functional Interfaces
8️⃣ Databases & JDBC: 🗄️🔗 SQL, MySQL, PostgreSQL
9️⃣ Spring Framework: 🌱🚀 Spring Boot, REST APIs
🔟 Projects & Practice: 📂📌 Build apps, contribute to open source

React ❤️ for more

𝟳 𝗕𝗲𝘀𝘁 𝗙𝗿𝗲𝗲 𝗥𝗲𝘀𝗼𝘂𝗿𝗰𝗲𝘀 𝘁𝗼 𝗟𝗲𝗮𝗿𝗻 & 𝗣𝗿𝗮𝗰𝘁𝗶𝗰𝗲 𝗣𝘆𝘁𝗵𝗼𝗻 𝗳𝗼𝗿 𝗗𝗮𝘁𝗮 𝗔𝗻𝗮𝗹𝘆𝘁𝗶𝗰𝘀😍

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𝐋𝐢𝐧𝐤👇:-

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Enjoy Learning ✅️

Java Roadmap
|
|-- Fundamentals
| |-- Basics of Programming
| | |-- Introduction to Java
| | |-- Java Development Kit (JDK) and Java Runtime Environment (JRE)
| | |-- Setting Up Development Environment (IDE: IntelliJ IDEA, Eclipse, etc.)
| |
| |-- Syntax and Structure
| | |-- Basic Syntax
| | |-- Variables and Data Types
| | |-- Operators and Expressions
|
|-- Control Structures
| |-- Conditional Statements
| | |-- If-Else Statements
| | |-- Switch Case
| |
| |-- Loops
| | |-- For Loop
| | |-- While Loop
| | |-- Do-While Loop
| |
| |-- Exception Handling
| | |-- Try-Catch Block
| | |-- Finally Block
| | |-- Throw and Throws Keywords
|
|-- Object-Oriented Programming (OOP)
| |-- Basics of OOP
| | |-- Classes and Objects
| | |-- Methods and Constructors
| |
| |-- Inheritance
| | |-- Single and Multiple Inheritance
| | |-- Method Overriding
| | |-- Super Keyword
| |
| |-- Polymorphism
| | |-- Method Overloading
| | |-- Runtime Polymorphism
| | |-- Dynamic Method Dispatch
| |
| |-- Encapsulation
| | |-- Access Modifiers (Public, Private, Protected)
| | |-- Getters and Setters
| | |-- Data Hiding
| |
| |-- Abstraction
| | |-- Abstract Classes
| | |-- Interfaces
|
|-- Advanced Java
| |-- Collections Framework
| | |-- List (ArrayList, LinkedList)
| | |-- Set (HashSet, TreeSet)
| | |-- Map (HashMap, TreeMap)
| | |-- Queue (PriorityQueue, LinkedList)
| |
| |-- Concurrency
| | |-- Multithreading (Creating Threads, Thread Lifecycle)
| | |-- Synchronization
| | |-- Concurrency Utilities (Executors Framework, Callable and Future, Locks and Semaphores)
|
|-- Java Standard Libraries
| |-- I/O Streams
| | |-- File Handling (File Class, Reading and Writing Files)
| | |-- Streams (Byte Streams, Character Streams, Buffered Streams)
| |
| |-- Networking
| | |-- Sockets (TCP and UDP, Socket and ServerSocket Classes)
| | |-- URL and HTTP (URL Class, HttpURLConnection)
| |
| |-- JDBC
| | |-- Database Connectivity (JDBC Drivers, Connection, Statement, and ResultSet)
| | |-- PreparedStatement and CallableStatement
|
|-- Java Frameworks
| |-- Spring Framework
| | |-- Spring Core (Dependency Injection, Inversion of Control)
| | |-- Spring MVC (Model-View-Controller Architecture)
| | |-- Spring Boot (Creating Spring Boot Applications, Starters and Auto-Configuration, Actuator)
| |
| |-- Hibernate
| | |-- ORM Basics (Introduction to ORM, Configuration and Mapping)
| | |-- Advanced Hibernate (Caching, Transactions and Concurrency, Criteria API)
|
|-- Web Development with Java
| |-- Java EE (Jakarta EE)
| | |-- Servlets (Lifecycle, Handling HTTP Requests and Responses, Session Management)
| | |-- JavaServer Pages (JSP) (Syntax, Directives, JSTL and Custom Tags, Expression Language)
| |
| |-- RESTful Web Services
| | |-- JAX-RS (Creating RESTful Services, Annotations and HTTP Methods, Consuming RESTful Services)
|
|-- Build Tools and Dependency Management
| |-- Maven
| | |-- Project Object Model (POM), Dependencies, Repositories, Build Lifecycle and Plugins
| |
| |-- Gradle
| | |-- Build Scripts, Dependency Management, Task Automation
|
|-- Testing in Java
| |-- Unit Testing
| | |-- JUnit (Annotations, Assertions, Test Suites and Runners)
| |
| |-- Mockito (Creating Mocks and Spies and Verification)
| |
| |-- Integration Testing
| | |-- Spring Test (Testing Spring Components and WebTestClient)
|
|-- Deployment and DevOps
| |-- Containers and Microservices
| | |-- Docker (Dockerfile, Image Creation, Container Management)
| | |-- Kubernetes (Pods, Services, Deployments, Managing Java Applications on Kubernetes)

Free books and courses to learn Java👇👇

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https://bit.ly/3BSHP5S

https://t.iss.one/Java_Programming_Notes

Join @free4unow_backup for more free courses

ENJOY LEARNING👍👍

𝗙𝗥𝗘𝗘 𝗠𝗶𝗰𝗿𝗼𝘀𝗼𝗳𝘁 𝗗𝗮𝘁𝗮 𝗔𝗻𝗮𝗹𝘆𝘁𝗶𝗰𝘀 𝗖𝗲𝗿𝘁𝗶𝗳𝗶𝗰𝗮𝘁𝗶𝗼𝗻 𝗖𝗼𝘂𝗿𝘀𝗲😍

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 The Career Essentials in Data Analysis program by Microsoft and LinkedIn is a 100% FREE learning path designed to equip you with real-world skills and industry-recognized certification.

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Enroll For FREE & Get Certified ✅️

9 beginner-friendly coding project ideas to build confidence:

📅 Digital Clock — show real-time hours, minutes, seconds
🎲 Dice Roller — generate random numbers with UI
📋 Quiz App — multiple choice questions with score tracking
🔢 Number Guessing Game — apply loops and conditionals
💬 Message Encoder/Decoder — basic string manipulation
🖼️ Image Slider — work with DOM and transitions
🔐 Password Generator — use randomization and user input
📈 Temperature Converter — switch between Celsius and Fahrenheit
✏️ Notes App — add, delete, and save notes with local storage

#coding #projects

𝟱 𝗙𝗿𝗲𝗲 𝗚𝗼𝗼𝗴𝗹𝗲 𝗔𝗜 𝗖𝗼𝘂𝗿𝘀𝗲𝘀 𝘁𝗼 𝗞𝗶𝗰𝗸𝘀𝘁𝗮𝗿𝘁 𝗬𝗼𝘂𝗿 𝗔𝗿𝘁𝗶𝗳𝗶𝗰𝗶𝗮𝗹 𝗜𝗻𝘁𝗲𝗹𝗹𝗶𝗴𝗲𝗻𝗰𝗲 𝗖𝗮𝗿𝗲𝗲𝗿😍

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List of Top 12 Coding Channels on WhatsApp:

1. Python Programming:
https://whatsapp.com/channel/0029VaiM08SDuMRaGKd9Wv0L


2. Coding Resources:
https://whatsapp.com/channel/0029VahiFZQ4o7qN54LTzB17


3. Coding Projects:
https://whatsapp.com/channel/0029VazkxJ62UPB7OQhBE502


4. Coding Interviews:
https://whatsapp.com/channel/0029VammZijATRSlLxywEC3X


5. Java Programming:
https://whatsapp.com/channel/0029VamdH5mHAdNMHMSBwg1s


6. Javascript:
https://whatsapp.com/channel/0029VavR9OxLtOjJTXrZNi32


7. Web Development:
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8. Artificial Intelligence:
https://whatsapp.com/channel/0029VaoePz73bbV94yTh6V2E


9. Data Science:
https://whatsapp.com/channel/0029Va4QUHa6rsQjhITHK82y


10. Machine Learning:
https://whatsapp.com/channel/0029Va8v3eo1NCrQfGMseL2D


11. SQL:
https://whatsapp.com/channel/0029VanC5rODzgT6TiTGoa1v


12. GitHub:
https://whatsapp.com/channel/0029Vawixh9IXnlk7VfY6w43

ENJOY LEARNING 👍👍

𝗧𝗼𝗽 𝟱 𝗙𝗿𝗲𝗲 𝗞𝗮𝗴𝗴𝗹𝗲 𝗖𝗼𝘂𝗿𝘀𝗲𝘀 𝘄𝗶𝘁𝗵 𝗖𝗲𝗿𝘁𝗶𝗳𝗶𝗰𝗮𝘁𝗶𝗼𝗻𝘀 𝘁𝗼 𝗝𝘂𝗺𝗽𝘀𝘁𝗮𝗿𝘁 𝗬𝗼𝘂𝗿 𝗗𝗮𝘁𝗮 𝗦𝗰𝗶𝗲𝗻𝗰𝗲 𝗖𝗮𝗿𝗲𝗲𝗿😍

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𝟱 𝗙𝗿𝗲𝗲 𝗠𝗶𝗰𝗿𝗼𝘀𝗼𝗳𝘁 + 𝗟𝗶𝗻𝗸𝗲𝗱𝗜𝗻 𝗖𝗮𝗿𝗲𝗲𝗿 𝗘𝘀𝘀𝗲𝗻𝘁𝗶𝗮𝗹 𝗖𝗲𝗿𝘁𝗶𝗳𝗶𝗰𝗮𝘁𝗶𝗼𝗻𝘀 𝘁𝗼 𝗕𝗼𝗼𝘀𝘁 𝗬𝗼𝘂𝗿 𝗥𝗲𝘀𝘂𝗺𝗲😍

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Java programming project ideas based on beginner, Intermediate & advanced level

Beginner Level:
1. To-Do List Application: Create a console-based to-do list manager where users can add, delete, and view tasks.
2. Simple Calculator: Build a basic calculator that can perform arithmetic operations like addition, subtraction, multiplication, and division.
3. Temperature Converter: Design a program that converts between Celsius and Fahrenheit.

Intermediate Level:
4. Bank Account Manager: Simulate a simple bank account management system with features like account creation, deposit, withdrawal, and balance inquiries.
5. Student Record System: Develop an application to manage student records, including information like name, roll number, and grades.
6. Inventory Management System: Create a program to manage inventory with features for adding, updating, and viewing product details.

Advanced Level:
7. Library Management System: Design a system to manage library resources, including books, patrons, and borrowing/returning books.
8. Online Quiz System: Build an interactive quiz application with multiple-choice questions and scoring.
9. Chat Application: Create a simple chat application where multiple users can exchange messages in real-time.

GUI Applications:
10. Expense Tracker: Develop a desktop application that allows users to input and track their daily expenses.
11. Image Viewer: Build an image viewer application that can display and manipulate images.
12. Music Player: Design a basic music player with features for playing audio files and creating playlists.

These projects cover a range of Java programming concepts and will help you become more proficient in Java. You can also expand and enhance these projects as you learn more. The key is to choose projects that interest you, so you stay motivated to complete them and continue learning.

Day 1/100

𝟱 𝗙𝗥𝗘𝗘 𝗛𝗮𝗿𝘃𝗮𝗿𝗱 𝗗𝗮𝘁𝗮 𝗖𝗼𝘂𝗿𝘀𝗲𝘀 𝘁𝗼 𝗞𝗶𝗰𝗸𝘀𝘁𝗮𝗿𝘁 𝗬𝗼𝘂𝗿 𝗗𝗮𝘁𝗮 𝗔𝗻𝗮𝗹𝘆𝘁𝗶𝗰𝘀 & 𝗗𝗮𝘁𝗮 𝗦𝗰𝗶𝗲𝗻𝗰𝗲 𝗝𝗼𝘂𝗿𝗻𝗲𝘆😍

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Polymorphism in Java

📍 Polymorphism allows a single interface to be used for different types of actions.
📍 It is of two types:

Method Overloading (Compile-time Polymorphism)

Method Overriding (Runtime Polymorphism)


Method Overloading (Same method name, different parameters)

class MathOperations {
int add(int a, int b) {
return a + b;
}

double add(double a, double b) {
return a + b;
}
}

Method Overriding (Same method in parent and child class)

class Animal {
void makeSound() {
System.out.println("Animal makes a sound");
}
}

class Dog extends Animal {
void makeSound() {
System.out.println("Dog barks");
}
}

🔗 More Java Resources: https://whatsapp.com/channel/0029VamdH5mHAdNMHMSBwg1s

𝟱 𝗙𝗥𝗘𝗘 𝗣𝘆𝘁𝗵𝗼𝗻 𝗖𝗼𝘂𝗿𝘀𝗲𝘀 𝗳𝗼𝗿 𝗕𝗲𝗴𝗶𝗻𝗻𝗲𝗿𝘀 𝗯𝘆 𝗛𝗮𝗿𝘃𝗮𝗿𝗱, 𝗜𝗕𝗠, 𝗨𝗱𝗮𝗰𝗶𝘁𝘆 & 𝗠𝗼𝗿𝗲😍

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Kickstart your career✅️

𝟰 𝗙𝗥𝗘𝗘 𝗠𝗶𝗰𝗿𝗼𝘀𝗼𝗳𝘁 & 𝗦𝘁𝗮𝗻𝗳𝗼𝗿𝗱 𝗖𝗼𝘂𝗿𝘀𝗲𝘀 𝗧𝗵𝗮𝘁 𝗪𝗶𝗹𝗹 𝗔𝗰𝘁𝘂𝗮𝗹𝗹𝘆 𝗨𝗽𝗴𝗿𝗮𝗱𝗲 𝗬𝗼𝘂𝗿 𝗥𝗲𝘀𝘂𝗺𝗲😍

I failed my first data interview — and here’s why:⬇️

❌ No structured learning
❌ No real projects
❌ Just random YouTube tutorials and half-read blogs

If this sounds like you, don’t repeat my mistake✨️
Recruiters want proof of skills, not just buzzwords📊

𝐋𝐢𝐧𝐤👇:-

https://pdlink.in/4ka1ZOl

All The Best 🎊

List of Top 12 Coding Channels on WhatsApp:

1. Python Programming:
https://whatsapp.com/channel/0029VaiM08SDuMRaGKd9Wv0L


2. Coding Resources:
https://whatsapp.com/channel/0029VahiFZQ4o7qN54LTzB17


3. Coding Projects:
https://whatsapp.com/channel/0029VazkxJ62UPB7OQhBE502


4. Coding Interviews:
https://whatsapp.com/channel/0029VammZijATRSlLxywEC3X


5. Java Programming:
https://whatsapp.com/channel/0029VamdH5mHAdNMHMSBwg1s


6. Javascript:
https://whatsapp.com/channel/0029VavR9OxLtOjJTXrZNi32


7. Web Development:
https://whatsapp.com/channel/0029VaiSdWu4NVis9yNEE72z


8. Artificial Intelligence:
https://whatsapp.com/channel/0029VaoePz73bbV94yTh6V2E


9. Data Science:
https://whatsapp.com/channel/0029Va4QUHa6rsQjhITHK82y


10. Machine Learning:
https://whatsapp.com/channel/0029Va8v3eo1NCrQfGMseL2D


11. SQL:
https://whatsapp.com/channel/0029VanC5rODzgT6TiTGoa1v


12. GitHub:
https://whatsapp.com/channel/0029Vawixh9IXnlk7VfY6w43

ENJOY LEARNING 👍👍

𝗟𝗲𝗮𝗿𝗻𝗶𝗻𝗴 𝗦𝗤𝗟 𝗖𝗮𝗻 𝗕𝗲 𝗙𝘂𝗻! 𝟰 𝗜𝗻𝘁𝗲𝗿𝗮𝗰𝘁𝗶𝘃𝗲 𝗣𝗹𝗮𝘁𝗳𝗼𝗿𝗺𝘀 𝗧𝗵𝗮𝘁 𝗙𝗲𝗲𝗹 𝗟𝗶𝗸𝗲 𝗮 𝗚𝗮𝗺𝗲😍

Think SQL is all about dry syntax and boring tutorials? Think again.🤔

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These platforms make SQL interactive, practical, and fun✅️