ADevGuide Interview Fundamentals
Core Java concepts, practical Q&A, and coding discussion topics asked in technical interviews.
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API Rate Limiting: Fixed Window, Sliding Window and Token Bucket
Series: Backend Interview Mastery
Learn API rate limiting for backend interviews: fixed and sliding windows, token bucket, Redis atomicity, 429 responses, and trade-offs.
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Idempotency in REST APIs: How to Prevent Duplicate Payments
Series: Backend Interview Mastery
Learn idempotency in REST APIs for backend interviews: idempotency keys, retries, race conditions, response replay, and duplicate-payment prevention.
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API Gateway Explained: Architecture, Responsibilities and Trade-offs
Series: Backend Interview Mastery
Learn API gateway architecture for backend interviews: routing, authentication, rate limiting, aggregation, failure handling, and trade-offs.
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Stateless vs Stateful Architecture for Backend Interviews
Series: Backend Interview Mastery , System Design Foundations
Learn stateless vs stateful architecture for backend interviews: where state lives, scaling trade-offs, sessions, Redis, and failure recovery.
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Tomcat vs JBoss WildFly: Differences and Use Cases
Series: Java Interview & Problem Solving Series
Compare Tomcat vs JBoss WildFly on Jakarta EE support, performance, clustering and use cases to choose the right Java server for your project.
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Reverse a Number in Java: Loop Logic and Code Example
Series: Java Interview & Problem Solving Series
Learn how to reverse a number in Java using while loop, modulo and division logic with step-by-step code example and iteration walkthrough tips.
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Regular Expressions in Java: Pattern, Matcher Guide
Series: Java Interview & Problem Solving Series
Learn regular expressions in Java with Pattern and Matcher, syntax, metacharacters, quantifiers and hands-on examples for validation and parsing.
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Is Java Pass by Value or Pass by Reference Explained
Series: Java Interview & Problem Solving Series
Understand Java pass by value with clear examples for primitives, objects, and collections, plus the common interview trap about pass by reference.
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Java Interfaces Explained with Code to Interface Guide
Series: Java Interview & Problem Solving Series
Learn Java interfaces with clear examples and how coding to an interface improves flexibility, testing, and clean object-oriented design in practice.
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Backend Developer Interview Guide: Concepts, Scenarios & System Design
Series: Backend Interview Mastery
Use this backend developer interview guide to prepare APIs, databases, caching, distributed systems, production scenarios, and system design.