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Browse Algorithms Java How-Tos Spring Framework
569 Algorithm problems
21 DS&A categories
121 Java articles
39 Spring articles
751+ Total articles

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Algorithms
Algorithms & DS

Patterns, walkthroughs and Java solutions.

569 problems
Java
Java How-Tos

Basics, Collections, IO, Modern Java 17–24, and advanced topics.

121 articles
Spring
Spring Framework

Core, Boot, Data JPA, AOP and more.

39 articles
Kafka
Kafka

Producers, consumers, topics and partitions.

14 articles
Apache Camel
Apache Camel

Integration framework — routes, EIPs, and connectors.

8 articles

Hand-picked reads

Featured Articles

Algorithms
LRU Cache — Design & Implementation

Build an O(1) LRU cache using a doubly-linked list combined with a HashMap.

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Spring Boot
Building REST APIs with @RestController

GET, POST, PUT, DELETE endpoints with path variables, request bodies and ResponseEntity.

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Java 21
Java Virtual Threads — Project Loom

Millions of lightweight threads with zero blocking — how virtual threads change concurrent Java forever.

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Algorithms
Dynamic Programming — Introduction

Memoization vs tabulation, recognising overlapping subproblems, general templates.

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Spring
Aspect Oriented Programming (AOP)

Logging, performance timing and cross-cutting concerns with @Aspect and @Around.

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Kafka
Kafka — Architecture Introduction

Producers, consumers, brokers, topics and partitions explained with diagrams.

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Java

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Inheritance & Polymorphism
Basics
⚙️
HashMap Internals
Advanced
⛏️
PriorityQueue
Collections
📦
Module System
Java 9+
🔐
final Keyword
Basics
🛡️
try-with-resources
Basics
🧵
Virtual Threads
Java 21+
🔒
Sealed Classes
Java 17+
⚡
CompletableFuture
Advanced
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Records
Java 16+
🔀
Pattern switch
Java 21+
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Algorithms

Popular Problem Categories

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Two Pointers
22
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30
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Dynamic Prog.
41
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Graphs
39
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Trees
34
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Binary Search
26
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Backtracking
20
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21
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Strings
47
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90
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