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Nov 4, 2026

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Arbiter (Java)

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12h ago

Learning Java from Scratch with Arbiter: Threads, Race Conditions, synchronized, and Deadlocks

Four threads, one counter, and a silently wrong total — fixed with synchronized, plus a deadlock caused and cured on purpose

Learning Java from Scratch with Arbiter: Threads, Race Conditions, synchronized, and Deadlocks

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Oct 27

Learning Java from Scratch with Arbiter — Streams API: Lazy Pipelines, reduce, groupingBy, and…

Day 14 of my Arbiter Learning Journey | Why a stream does nothing until a terminal operation asks, how groupingBy can total while it…

Word tiles flowing through a pipeline of filter, map, and collect stations, transaction cards sorted into Groceries and Electronics bins with totals, and an Optional capsule with an orElseGet fallback beside it.

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Oct 22

Learning Java from Scratch with Arbiter — Lambdas: Functional Interfaces, Method References, and…

Day 13 of my Arbiter Learning Journey | Why a lambda needs exactly one abstract method to land on, why the built-in interfaces can’t throw…

A lambda symbol sliding into a single-slot keyhole on the left, and on the right a pipeline of Predicate and Function nodes joined by .and() and .andThen(), filtering employee records with one card marked INVALID_RECORD.

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Oct 12

Learning Java from Scratch with Arbiter — Generics: Bounded Type Parameters, Wildcards, and PECS

Day 12 of my Arbiter Learning Journey | Why a bound is a promise the compiler holds you to, why ? extends reads and ? super writes, and how…

A typed box that admits only comparable values on the left, and two opposing pipes on the right showing data read out of a list with ? extends and written into a list with ? super.

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Oct 9

Learning Java from Scratch with Arbiter — Exceptions: try/catch/finally, Checked vs.

Day 11 of my Arbiter Learning Journey | Why finally is the "always" block, how the parent class you extend decides checked vs. unchecked…

A dark illustration of a withdrawal ledger with one approved and one rejected transaction, next to two stacked resource blocks being released in reverse order just before a catch net.

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Oct 4

Learning Java from Scratch with Arbiter — Regex: Pattern, Matcher, find() Loops, and MULTILINE Log…

Day 10 of my Arbiter Learning Journey | Why matches() and find() are not the same question, how one compiled Pattern walks every line of a…

A developer at a night-time desk with two monitors: one checking product codes against a pattern with green ticks and red crosses, the other showing a log file with valid lines highlighted and noise lines dimmed.

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Aug 29

Learning Java from Scratch with Arbiter — Strings: Immutability, Regex Normalisation, and…

Day 9 of my Arbiter Learning Journey | Why every String method returns a new object, collapsing messy whitespace with one regex quantifier…

A person in a knit sweater types at a wooden desk in a dimly lit room at night, lit by a warm amber lamp and two glowing monitors. The left monitor shows a messy sentence with irregular spacing transformed into a clean title-cased sentence below it. The right monitor shows a row of character cells with an index ruler beneath, a green arrow inserting a character into a gap and a red arrow removing one.

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Aug 21

Learning Java from Scratch with Arbiter — Maps: getOrDefault() Counting, LinkedHashMap Order, and…

Day 8 of my Arbiter Learning Journey | Counting frequencies without a containsKey branch, making iteration order a guarantee instead of a…

A person in a knit sweater types at a wooden desk in a dimly lit room at night, lit by a warm amber lamp and two glowing monitors. The left monitor shows three labeled diagrams of Java Map types: a HashMap as scattered blue buckets in unpredictable order, a LinkedHashMap as the same buckets threaded by an orange arrow in strict order, and a TreeMap as a purple balanced binary tree with sorted nodes.

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Aug 17

Learning Java from Scratch with Arbiter — Arrays & Core Collections: Ring Traversal, Iterator.remove

Day 7 of my Arbiter Learning Journey | Extracting concentric rings from a 2D array, removing safely from a live ArrayList with…

A man in a dark hoodie types on a mechanical keyboard at a wooden desk in a dimly lit room. Two monitors glow in front of him. The left monitor shows a 5x5 grid of numbers (1–25) arranged in a square, with blue and purple circular arrows indicating a spiral path and the center cell highlighted in gold. The right monitor displays a code editor showing Java syntax comparing ArrayList and LinkedList methods, alongside a diagram of a linked list with arrows between boxes.

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Aug 13

Learning Java from Scratch with Arbiter — Abstraction & Interfaces: Default Methods and the…

Day 6 of my Arbiter Learning Journey | Mixing abstract classes with interfaces, getting default methods for free, and proving why equals()…

Cozy night coding desk with dual monitors showing Java interface and abstract class code alongside a glowing diagram of equals() and hashCode() intersecting above a HashSet icon. Desk has coffee and a notebook

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Aug 11

Learning Java from Scratch with Arbiter — Inheritance & Polymorphism: extends, super, and Dynamic…

Day 5 of my Arbiter Learning Journey | Building subclass hierarchies with extends and super, overriding behavior with @Override, and…

Cozy night coding setup with dual screens showing Java inheritance code and neon UML diagrams. Desk has coffee and notebook

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Aug 9

Learning Java from Scratch with Arbiter — OOP Core: Classes, Constructors & Encapsulation

Day 4 of my Arbiter Learning Journey | Building objects from blueprints, protecting state behind private fields, and proving how static…

A detailed, stylized illustration of a programmer’s dual-monitor desk setup at night. The left monitor displays Java code for a Product class. The right monitor shows a glowing conceptual diagram comparing Class Blueprints, shared static data, and multiple Object Instances. Below the screens, on the desk, an open notebook features hand-drawn diagrams for ‘private fields’ and ‘public getter/setter’ next to a steaming mug and mechanical keyboard.

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Aug 4

Learning Java from Scratch with Arbiter — Methods: Overloading, Varargs & the Pass-by-Value Trap

Day 3 of my Arbiter Learning Journey | Declaring, overloading, and recursing through methods — then proving exactly how Java passes array…

A dark-themed vector illustration of a modern night-time desk setup with two monitors, a keyboard, mouse, headphones, and a steaming mug. The left monitor shows Java code defining a recursive factorial function, with the method signature and call highlighted. The right monitor displays a vertical, glowing visualization of the call stack as translucent blue panels. On the desk, an open notebook contains handwritten diagrams of stack frames.

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Aug 3

Learning Java from Scratch with Arbiter — Control Flow: Decisions, Loops & Labeled Breaks

Day 2 of my Arbiter Learning Journey | Teaching Java programs to branch, repeat, and escape nested loops with precision

An illustration of a programmer’s desk at night. On the left screen, Java code is visible in a dark editor. On the right screen, a robot icon is navigating a green and orange grid, following a dashed path toward a red destination cell. On the desk are a steaming coffee mug, an open notebook with hand-drawn flowcharts, a keyboard, mouse, and headphones. A desk lamp provides warm light on the left. The background shows a city skyline at night

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Aug 2

Learning Java from Scratch with Arbiter — Variables, Data Types, Input & Output

Day 1 of my Arbiter Learning Journey | Building Java fundamentals before building production-ready microservices

An illustration of a modern, dimly lit developer’s desk. A large computer monitor in the center displays Java code in a dark IDE. On the wall behind the monitor is a complex, illuminated architectural diagram showing various microservices, an event bus, and an API gateway with orange glowing connectors. The desk holds a mechanical keyboard, mouse, headphones, a steaming coffee mug, and an open notebook with hand-drawn sketches. The overall style is clean, flat-vector, and professional.