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JVM restart issue resolution To resolve JVM restart issues, consider the following actions:   1. Address Memory Issues: Increase Heap Size:  Insufficient JVM heap memory is a common cause of restarts, leading to  OutOfMemoryError . Increase the heap size (e.g., -Xms and -Xmx) to accommodate the application's memory requirements. Enable Heap Dump and GC Logs:  Configure the JVM to generate a heap dump on  OutOfMemoryError  and enable garbage collection logs for analysis to identify memory leaks or inefficiencies. Fix Memory Leaks:  Identify and fix memory leaks in your code where objects are not properly released, leading to increasing memory usage. Adjust Stack Size:  If stack overflow errors occur, increase the stack size using the  -Xss  parameter. Check for Native Memory Exhaustion:  If the JVM or application uses excessive native memory, it can lead to crashes. Troubleshoot JNI code for memory leaks.   2. Optimize Applicati...

 A software engineer needs a combination of technical , soft , and domain-specific skills to succeed in their role. Here's a detailed breakdown: 🧠 Technical Skills Programming Languages Core Languages : Proficiency in at least one language such as: JavaScript, Python, Java, C++, C#, Go, or Rust. Language Paradigms : Understanding OOP, functional, and procedural programming. Data Structures & Algorithms Arrays, Linked Lists, Trees, Graphs, Hash Tables Sorting/searching, recursion, dynamic programming Big-O notation and performance optimization Software Design & Architecture Design patterns (e.g., Singleton, Factory, Observer) Principles (SOLID, DRY, KISS, YAGNI) Layered architecture, microservices, event-driven architecture Version Control Git: branching, merging, pull requests, conflict resolution Platforms: GitHub, GitLab, Bitbucket Databases Relational : MySQL, PostgreSQL NoSQL : MongoDB, Redis, Cas...

 Sure! Let's dive deep into Reactive Programming in the context of Spring WebFlux , especially as it relates to Java development and interviews. ⚡ What is Reactive Programming? Reactive Programming is a programming paradigm focused on: Asynchronous data streams Non-blocking behavior Backpressure handling (flow control) Rather than processing one request at a time, it reacts to events/data as they arrive, making it ideal for handling high-concurrency , I/O-bound , or real-time applications . 🌐 What is Spring WebFlux? Spring WebFlux is a reactive web framework introduced in Spring 5 and available via Spring Boot 2.x and 3.x . 🔑 Key Characteristics: Feature Description Reactive Stack Built on Project Reactor Non-blocking I/O Uses Netty (or can run on Tomcat/Jetty/Undertow in non-blocking mode) Alternative to MVC WebFlux is to Reactive what Spring MVC is to traditional Functional or Annotated Supports both annotation-based ( @RestC...

 Here’s a detailed explanation of the different versions and releases of Spring Boot , focusing on what’s most relevant from a Java Developer / Software Developer interview perspective — followed by a visual timeline . 🚀 What is Spring Boot? Spring Boot is a tool built on top of the Spring Framework to make it easier and faster to build, test, and deploy Java applications — especially REST APIs and microservices. Key Concepts: Auto-Configuration Embedded servers (Tomcat/Jetty) Opinionated defaults Spring Boot Starters Actuator for Monitoring 📅 Major Spring Boot Versions & Features (Interview-Centric) 🔹 Spring Boot 1.x (2014–2017) Spring Boot 1.0 released in April 2014 Features: Introduction of @SpringBootApplication Embedded Tomcat , Jetty , or Undertow Auto-configuration and Starters Properties-based configuration ( application.properties ) Basic Spring Actuator Interview Notes: Understand why Spring Boot was introduced ...

 Sure! Here’s a detailed breakdown of the different Java Spring Framework versions and their major releases , from the perspective of what a Java Developer or Software Developer should know for interviews. This includes evolution, features , and what might be commonly asked. ✅ Overview of Spring Framework The Spring Framework is a powerful, lightweight framework used for developing Java applications, especially enterprise-level applications. It provides comprehensive infrastructure support for developing Java applications and is known for: Dependency Injection (DI) Aspect-Oriented Programming (AOP) Spring MVC (Web Framework) Data access with JDBC, JPA Spring Boot (for microservices) 📅 Spring Framework Major Versions and Key Features 🔹 Spring Framework 1.x (2004) Highlights: Initial release by Rod Johnson (author of Expert One-on-One J2EE Design and Development ) Introduced IoC (Inversion of Control) and AOP Replaced heavy EJB-based solutions ...

T-SQL (Transact-SQL) is Microsoft's extension of SQL (Structured Query Language) used in SQL Server. It adds procedural programming, error handling, and transaction control to standard SQL. 1. Introduction to T-SQL SQL vs. T-SQL : SQL is a standard language for managing relational databases. T-SQL extends SQL with procedural features like variables, loops, and error handling. 2. Basic Querying SELECT Statement SELECT column1, column2 FROM TableName; Retrieve specific columns from a table. WHERE Clause SELECT * FROM Employees WHERE Age > 30; Filters rows based on conditions. ORDER BY Clause SELECT * FROM Employees ORDER BY LastName ASC; Sorts results in ascending or descending order. GROUP BY and HAVING SELECT Department, COUNT(*) AS EmployeeCount FROM Employees GROUP BY Department HAVING COUNT(*) > 5; Groups data and filters grouped results. 3. Data Manipulation (DML) INSERT INSERT INTO Employees (FirstName, LastName, Age) VALUES ('Joh...