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Browse Algorithms Java How-Tos Spring Framework
569 Algorithm problems
21 DS&A categories
52 Java articles
15 Spring articles
640+ Total articles

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Algorithms
Algorithms & DS

Patterns, walkthroughs and Java solutions.

569 problems
Java
Java How-Tos

Collections, IO, Modern Java 17–21, and advanced topics.

52 articles
Spring
Spring Framework

Core, Boot, Data JPA, AOP and more.

15 articles
Kafka
Kafka

Producers, consumers, topics and partitions.

4 articles
Build Tools
Build Tools

Maven setup, project configuration and more.

Guides

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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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Algorithms

Popular Problem Categories

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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
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Trees
34
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Binary Search
26
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Backtracking
20
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Heap / PQ
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Strings
47
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90
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