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Browse Algorithms Java How-Tos Spring Framework
569 Algorithm problems
21 DS&A categories
100 Java articles
29 Spring articles
708+ 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.

100 articles
Spring
Spring Framework

Core, Boot, Data JPA, AOP and more.

29 articles
Kafka
Kafka

Producers, consumers, topics and partitions.

10 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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Records
Java 16+
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Virtual Threads
Java 21+
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Sealed Classes
Java 17+
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Pattern switch
Java 21+
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CompletableFuture
Advanced
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45 more topics
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Algorithms

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Two Pointers
22
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Sliding Window
30
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Dynamic Prog.
41
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Graphs
39
🌳
Trees
34
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Binary Search
26
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Backtracking
20
⛰️
Heap / PQ
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Strings
47
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Arrays
90
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System Design
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