[JENKINS-49217] Export ChannelTermination#cause when it is an ExportedBean

Description

Contributor guide

Tech stack

java

Domain

apibackend

Issue type

feature

DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.

2

Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.

1-3 hours

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.

clear

Prerequisites

Java knowledgeJenkins plugin development basicsUnderstanding of @ExportedBean annotations

Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.

70

Research direction

This issue is a follow up to JENKINS 24452, which previously attempted to export the cause field but hit a NotExportableException for non ExportedBean objects. The solution involves checking if the cause object (class ChannelTermination.Cause) has @ExportedBean annotations; if not, wrap it in an ExportedBean container. Review the file 'hudson/slaves/OfflineCause.java' and understand the existing remoting export mechanism. There are 9 comments in the GitHub issue (link: #22545) that may provide additional context.