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Suresh sureshg

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@elizarov
elizarov / DeepRecursiveFunction.kt
Last active March 25, 2024 00:40
Defines recursive function that keeps its stack on the heap (productized version)
import kotlin.coroutines.*
import kotlin.coroutines.intrinsics.*
/**
* Defines deep recursive function that keeps its stack on the heap,
* which allows very deep recursive computations that do not use the actual call stack.
* To initiate a call to this deep recursive function use its [invoke] function.
* As a rule of thumb, it should be used if recursion goes deeper than a thousand calls.
*
* The [DeepRecursiveFunction] takes one parameter of type [T] and returns a result of type [R].
@naturalwarren
naturalwarren / CoinbaseRxJava2CallAdapterFactory.kt
Last active September 17, 2025 11:40
A Kotlin-esque API for Retrofit.
/**
* Copyright 2019 Coinbase, Inc.
*
* Licensed under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
/*
* Copyright (C) 2018 Square, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
@rxwei
rxwei / ad-manifesto.md
Last active December 6, 2024 16:54
First-Class Automatic Differentiation in Swift: A Manifesto
@tomwhoiscontrary
tomwhoiscontrary / Main.java
Last active June 25, 2024 16:37
A simple Java web server with basic logging, tracing, health check, graceful shutdown and zero dependencies
import com.sun.net.httpserver.Filter;
import com.sun.net.httpserver.HttpExchange;
import com.sun.net.httpserver.HttpHandler;
import com.sun.net.httpserver.HttpServer;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.InetSocketAddress;
import java.util.Arrays;
import java.util.List;

Quick Tips for Fast Code on the JVM

I was talking to a coworker recently about general techniques that almost always form the core of any effort to write very fast, down-to-the-metal hot path code on the JVM, and they pointed out that there really isn't a particularly good place to go for this information. It occurred to me that, really, I had more or less picked up all of it by word of mouth and experience, and there just aren't any good reference sources on the topic. So… here's my word of mouth.

This is by no means a comprehensive gist. It's also important to understand that the techniques that I outline in here are not 100% absolute either. Performance on the JVM is an incredibly complicated subject, and while there are rules that almost always hold true, the "almost" remains very salient. Also, for many or even most applications, there will be other techniques that I'm not mentioning which will have a greater impact. JMH, Java Flight Recorder, and a good profiler are your very best friend! Mea

@cbeyls
cbeyls / KotlinFunctions.md
Last active February 28, 2025 09:59
Comparison of Kotlin functions: also, apply, let, run, with
Function Function type Target passed as Returns
also Extension it Target
apply Extension this Target
let Extension it Block return value
run Extension this Block return value
with Regular this Block return value
@elizarov
elizarov / Result.kt
Last active June 16, 2020 17:04
Result for Kotlin
class Result<T> private constructor(private val result: Any?) {
// discovery
val isFailure: Boolean get() = result is Failure
val isSuccess: Boolean get() = result !is Failure
// value retrieval
fun get(): T =
if (result is Failure) throw result.exception
@thomasnield
thomasnield / JdbcToDataClass.kt
Last active June 3, 2017 00:31
JDBC ResultSet to Data Class
// Bring in Google Guava as a dependency
// compile 'com.google.guava:guava:22.0'
import com.google.common.base.CaseFormat
import java.sql.ResultSet
fun ResultSet.toDataClass(): String {
import org.gradle.api.file.SourceDirectorySet
import org.gradle.api.internal.HasConvention
import org.gradle.api.tasks.SourceSet
import org.gradle.api.tasks.SourceSetContainer
import org.jetbrains.kotlin.gradle.plugin.KotlinSourceSet
import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
//β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”
// BUILD SCRIPT.
//β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”