--- title: "#kotlin-beginner articles | Hashnode" description: "Explore 416 articles tagged #kotlin-beginner on Hashnode. Tutorials, guides, and how-tos from the community." url: "https://hashnode.com/tag/kotlin-beginner" --- Tag # #kotlin-beginner 416 posts · 417 followers [Mayank Kumar](https://hashnode.com/@imayankkumar) · [Nov 3](https://hashnode.com/posts/kotlin-null-safety/6aea380f79648d8b5de7b4c0) ### [Kotlin Null Safety Explained Simply: ?, ?., ?:, !! and Platform Types](https://imayankkumar.hashnode.dev/kotlin-null-safety?utm_source=hashnode&utm_medium=feed) How Kotlin stops NullPointerException before your app runs: nullable types, safe calls, the Elvis operator, why !! is risky, and where Java can still crash you. 7 min read · [imayankkumar.hashnode.dev](https://imayankkumar.hashnode.dev/kotlin-null-safety?utm_source=hashnode&utm_medium=feed) [Shalen Mathew](https://hashnode.com/@shalenmathew) · [Jul 5](https://hashnode.com/posts/android-ci-cd-for-beginners/6a4a7b100ba01b189ff09108) ### [Android CI/CD for Beginners - Part 1: Introduction](https://shalenmathew.hashnode.dev/android-ci-cd-for-beginners?utm_source=hashnode&utm_medium=feed) Stop building everything manually. Learn how modern Android teams automate their development workflow 6 min read · [shalenmathew.hashnode.dev](https://shalenmathew.hashnode.dev/android-ci-cd-for-beginners?utm_source=hashnode&utm_medium=feed) [Ganesh Rama Hegde](https://hashnode.com/@hegde10122) · [Feb 21](https://hashnode.com/posts/chapter-30-usecase27-flow-cancellation-cooperative-cancellation/6999ddbd1ea55229dbb50438) ### [Chapter 30 : UseCase27 - Flow Cancellation & Cooperative Cancellation](https://kotlinflow.hashnode.dev/chapter-30-usecase27-flow-cancellation-cooperative-cancellation?utm_source=hashnode&utm_medium=feed) Flow cancellation is not an optional feature. It is a core part of how coroutines are designed to behave. When a collector stops collecting, the entire upstream flow is cancelled automatically. This i 6 min read · [kotlinflow.hashnode.dev](https://kotlinflow.hashnode.dev/chapter-30-usecase27-flow-cancellation-cooperative-cancellation?utm_source=hashnode&utm_medium=feed) [Ganesh Rama Hegde](https://hashnode.com/@hegde10122) · [Feb 21](https://hashnode.com/posts/chapter-29-usecase26-channels-and-flow-bridge/6999a568649f185d24e98f46) ### [Chapter 29 : UseCase26 - Channels and Flow Bridge](https://kotlinflow.hashnode.dev/chapter-29-usecase26-channels-and-flow-bridge?utm_source=hashnode&utm_medium=feed) Now we do one level below Flow. Flow is built on coroutines.Coroutines are built on channels. Here we convert channel to Flow and build Flow using channelFlow. We also understand producer-consumer in 4 min read · [kotlinflow.hashnode.dev](https://kotlinflow.hashnode.dev/chapter-29-usecase26-channels-and-flow-bridge?utm_source=hashnode&utm_medium=feed) [Ganesh Rama Hegde](https://hashnode.com/@hegde10122) · [Feb 20](https://hashnode.com/posts/chapter-27-usecase24-stateflow-state-holder-semantics/699893302de7857aa67d3417) ### [Chapter 27 : UseCase24 - StateFlow (State Holder Semantics)](https://kotlinflow.hashnode.dev/chapter-27-usecase24-stateflow-state-holder-semantics?utm_source=hashnode&utm_medium=feed) What is StateFlow? StateFlow is a special type of SharedFlow that: Always holds a current value Requires an initial value Replays the latest value to new collectors Conflates updates automatically 3 min read · [kotlinflow.hashnode.dev](https://kotlinflow.hashnode.dev/chapter-27-usecase24-stateflow-state-holder-semantics?utm_source=hashnode&utm_medium=feed) [Ganesh Rama Hegde](https://hashnode.com/@hegde10122) · [Feb 18](https://hashnode.com/posts/chapter-24-usecase21-conflation-deep-dive/6996056cb989a0d19d2be09d) ### [Chapter 24 : UseCase21 - Conflation Deep Dive](https://kotlinflow.hashnode.dev/chapter-24-usecase21-conflation-deep-dive?utm_source=hashnode&utm_medium=feed) buffer() in Chapter 23 was all about “queue everything” when the consumer is slow. Now we look into conflate() which is all about “dropping intermediate values” and caring only about the latest value. The Core Idea When the consumer is slow: buffer(... 3 min read · [kotlinflow.hashnode.dev](https://kotlinflow.hashnode.dev/chapter-24-usecase21-conflation-deep-dive?utm_source=hashnode&utm_medium=feed) [Ganesh Rama Hegde](https://hashnode.com/@hegde10122) · [Feb 16](https://hashnode.com/posts/chapter-21-usecase18-exception-handling-in-flow/699362c3276878bb42427b94) ### [Chapter 21 : UseCase18 - Exception Handling in Flow](https://kotlinflow.hashnode.dev/chapter-21-usecase18-exception-handling-in-flow?utm_source=hashnode&utm_medium=feed) Flow gives us structured exception handling. Business Scenario We will: Process stocks Throw an artificial exception for demonstration Handle it safely using catch Continue flow gracefully Code Implementation package org.kotlinflowlearner.stock... 3 min read · [kotlinflow.hashnode.dev](https://kotlinflow.hashnode.dev/chapter-21-usecase18-exception-handling-in-flow?utm_source=hashnode&utm_medium=feed) [Ganesh Rama Hegde](https://hashnode.com/@hegde10122) · [Feb 15](https://hashnode.com/posts/chapter-20-usecase17-zip/6992120259d0758c8426abaa) ### [Chapter 20 : UseCase17 - zip](https://kotlinflow.hashnode.dev/chapter-20-usecase17-zip?utm_source=hashnode&utm_medium=feed) In this chapter we will use zip() for synchronised business streams. Business Scenario We want to: Take top N stocks by market cap Take top N stocks by price Pair them position-wise Produce a comp 4 min read · [kotlinflow.hashnode.dev](https://kotlinflow.hashnode.dev/chapter-20-usecase17-zip?utm_source=hashnode&utm_medium=feed) [Ajimsimbom Bong M](https://hashnode.com/@ajimbong) · [Jan 31](https://hashnode.com/posts/kotlin-fundamentals/697df53995f52c1e90f1f509) ### [Kotlin Fundamentals](https://blog.ajim.dev/kotlin-fundamentals?utm_source=hashnode&utm_medium=feed) A guide that covers the fundamental aspects of the Kotlin programming language: variables, control flow, functions, and lambdas 5 min read · [blog.ajim.dev](https://blog.ajim.dev/kotlin-fundamentals?utm_source=hashnode&utm_medium=feed) [Ganesh Rama Hegde](https://hashnode.com/@hegde10122) · [Jan 29](https://hashnode.com/posts/chapter-15-usecase12-combine/6990c8d89f1fb8b8a053712d) ### [Chapter 15 : UseCase12 - combine()](https://kotlinflow.hashnode.dev/chapter-15-usecase12-combine?utm_source=hashnode&utm_medium=feed) combine() merges two flows. But unlike zip(), it does not wait for matching pairs. Instead, whenever either flow emits, combine uses the latest value from both flows. This makes it reactive and contin 4 min read · [kotlinflow.hashnode.dev](https://kotlinflow.hashnode.dev/chapter-15-usecase12-combine?utm_source=hashnode&utm_medium=feed)