twitter/finagle

Don't mess with class loaders... or do it gently

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#357 opened on Apr 1, 2015

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 (2 comments) (0 reactions) (0 assignees)Scala (8,864 stars) (1,435 forks)batch import
good first issue

Description

Issue is described in following thread: https://groups.google.com/forum/#!topic/finaglers/snRvOYwljbI Basically Play's auto-reloading breaks Finagle's reflection based API. Also @jproper gives good explanation of what's going on and how to fix it here: https://github.com/playframework/playframework/issues/4159

Contributor guide

Tech stack
scala
Domain
backendapi
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
4
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
3-5 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
mostly clear
Prerequisites
JVM class loadingScala programmingFinagle internalsPlay auto reloading
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
20
Research direction
Start by reading the referenced Google Groups thread and Play issue #4159 for context on the problem and proposed fix. Then examine Finagle's codebase for reflection based API calls, particularly in the core module, to understand how class loaders are used. The fix likely involves adjusting class loader usage to avoid conflicts with Play's auto reloading. No active PRs exist, so this requires original implementation based on the discussion.