Phase 2 - Core Java APIs

Goal: Use the standard library confidently. Understand generics, collections, streams, concurrency, and JVM internals.

Module	Topic	Status
12	Generics - type params, wildcards, PECS, type erasure	✅
13	Collections Framework - List, Set, Map, Queue, algorithms	✅
14	Streams API - filter/map/collect, Collectors, primitives	✅
15	Functional Programming - Optional, method references	✅
16	I/O, NIO.2 & Serialization	✅
17	Multithreading & Thread Management	✅
18	Java Memory Model & Advanced Concurrency	✅
19	Networking & Sockets - TCP, UDP, HttpClient, NIO Selector	✅
20	Annotations - custom, built-in, meta-annotations, runtime reflection	✅
21	Reflection API - Class inspection, field/method access, dynamic proxies	✅
22	Modern Java (9–21) - records, pattern matching, sealed classes, text blocks, var	✅
23	Algorithms & Data Structures - sorting, search, DS implementations, patterns	✅
24	JVM Internals - GC, JIT, ClassLoaders, reference types, performance	✅

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Table of contents

• 12 - Generics
• 13 - Collections Framework
• 14 - Streams API
• 15 - Functional Programming
• 16 - I/O, NIO.2 & Serialization
• 17 - Multithreading
• 18 - JMM & Advanced Concurrency
• 19 - Networking & Sockets
• 20 - Annotations
• 21 - Reflection API
• 22 - Modern Java (9–21)
• 23 - Algorithms & Data Structures
• 24 - JVM Internals