Add documentation for onDiscard callback in Java, Android, and Spring Boot

[alexander-alderman-webb]

… Boot

DESCRIBE YOUR PR

Tell us what you're changing and why. If your PR resolves an issue, please link it so it closes automatically.

Documents getsentry/sentry-java#4612

SLA

• Teamwork makes the dream work, so please add a reviewer to your PRs.
• Please give the docs team up to 1 week to review your PR unless you've added an urgent due date to it.
  Thanks in advance for your help!

PRE-MERGE CHECKLIST

Make sure you've checked the following before merging your changes:

• Checked Vercel preview for correctness, including links
• PR was reviewed and approved by any necessary SMEs (subject matter experts)
• PR was reviewed and approved by a member of the Sentry docs team

LEGAL BOILERPLATE

Look, I get it. The entity doing business as "Sentry" was incorporated in the State of Delaware in 2015 as Functional Software, Inc. and is gonna need some rights from me in order to utilize my contributions in this here PR. So here's the deal: I retain all rights, title and interest in and to my contributions, and by keeping this boilerplate intact I confirm that Sentry can use, modify, copy, and redistribute my contributions, under Sentry's choice of terms.

EXTRA RESOURCES

• Sentry Docs contributor guide

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Project	Deployment	Preview	Comments	Updated (UTC)
sentry-docs	✅ Ready	Preview	Comment	Aug 12, 2025 2:00pm

1 Skipped Deployment

Project	Deployment	Preview	Comments	Updated (UTC)
develop-docs	⬜️ Ignored			Aug 12, 2025 2:00pm

[codecov]

Bundle Report

Changes will increase total bundle size by 13.12kB (0.06%) ⬆️. This is within the configured threshold ✅

Detailed changes

Bundle name	Size	Change
sentry-docs-client-array-push	9.85MB	-6 bytes (-0.0%) ⬇️
sentry-docs-server-cjs	12.39MB	13.13kB (0.11%) ⬆️

Affected Assets, Files, and Routes:

view changes for bundle: sentry-docs-server-cjs

Assets Changed:

Asset Name	Size Change	Total Size	Change (%)
1729.js	-3 bytes	1.77MB	-0.0%
../instrumentation.js	-3 bytes	1.1MB	-0.0%
9523.js	-3 bytes	1.08MB	-0.0%
../app/[[...path]]/page.js.nft.json	4.38kB	748.58kB	0.59%
../app/platform-redirect/page.js.nft.json	4.38kB	748.49kB	0.59%
../app/sitemap.xml/route.js.nft.json	4.38kB	745.96kB	0.59%

view changes for bundle: sentry-docs-client-array-push

Assets Changed:

Asset Name	Size Change	Total Size	Change (%)
static/chunks/pages/_app-*.js	-3 bytes	882.71kB	-0.0%
static/chunks/8321-*.js	-3 bytes	425.87kB	-0.0%
server/middleware-*.js	-5.55kB	1.0kB	-84.74%
server/middleware-*.js	5.55kB	6.55kB	555.3% ⚠️
static/vlBwxZhV9diU9MXyYgoml/_buildManifest.js (New)	684 bytes	684 bytes	100.0% 🚀
static/vlBwxZhV9diU9MXyYgoml/_ssgManifest.js (New)	77 bytes	77 bytes	100.0% 🚀
static/J11oGDy1aB2DDuIWnLIzP/_buildManifest.js (Deleted)	-684 bytes	0 bytes	-100.0% 🗑️
static/J11oGDy1aB2DDuIWnLIzP/_ssgManifest.js (Deleted)	-77 bytes	0 bytes	-100.0% 🗑️

[adinauer]

LGTM. Thanks!