AEM Cloud Service in 2026: The Java API Deadline Has Passed and Java 25 Is Next. Here's the Dev Checklist

Two Java items in the AEM as a Cloud Service release notes affect almost every team with custom code: a deprecated API deadline that has already passed, and a Java 25 runtime migration with fixed target dates. Here’s what Adobe’s current notes say, with exact dates.

1. Deprecated Java APIs: deadline was September 28, 2026

Adobe’s notes list packages slated for removal, including org.apache.sling.commons.auth, org.apache.felix.webconsole, org.eclipse.jetty, com.mongodb, org.apache.log4j, ch.qos.logback, org.slf4j.spi, org.slf4j.event, com.google.common, com.drew, org.apache.abdera, org.apache.cocoon.xml, org.apache.felix.http.whiteboard and org.apache.jackrabbit.oak.plugins.memory.

• Since April 14, 2026: per the notes, Cloud Manager pipelines with code using these APIs fail at the Code Quality step, and deployment is blocked until the usage is removed. This is not a 2026.9 change.
• After September 28, 2026: environments still using them stop receiving critical Adobe release updates and fall outside Adobe’s standard performance and availability commitments. Adobe warns this can mean no new features or bug fixes, and higher stability and security risk.
• One discrepancy: the 2026.7.0 notes gave September 14, while later notes use September 28. I used the later date. Check the current page.
• Practical step: Adobe recommends the AEM CS SDK Build Analyzer Maven Plugin to find deprecated usage. com.google.common (Guava) and the logging packages are the likeliest to be hiding in transitive dependencies. Run a dependency tree before assuming your own code is clean.

2. Java 25 runtime: the target timeline

Adobe presents Java 25 as the next LTS after Java 21. These are target dates, and Adobe says changes will be posted in release notes:

• Mid-October 2026: SDK supports the Java 25 runtime, and the JDK is available from the Adobe Software Distribution portal.
• November 2026: optional. Enable Java 25 in your cloud environments to validate behavior.
• February to May 2027: Adobe migrates lower environments (RDE, Dev) gradually. Staging and production are encouraged but optional, and a temporary rollback to Java 21 is available.
• June 2027: all environments, including staging and production, move to Java 25. Java 21 runtime is decommissioned and the SDK stops supporting Java 21.

Customer code can still be compiled with Java 11, 17 or 21. Adobe recommends building with Java 25 once available.

Caveat: a Knowledge Base article from late September said Eclipse Temurin JDK 25 wasn’t yet supported for local development, SDK use or Cloud Manager builds, and recommended Oracle JDK 21. That predates the mid-October SDK milestone, so confirm what’s supported today before changing your toolchain.

3. New in the 2026.9.0 notes: tooling that can help (no status label on the page)

• AEM Query Optimization in the Code Assessment Agent Skill: checks whether a JCR/Oak query is actually served by an index and flags index definitions that look right but are subtly misconfigured. The notes say it’s available from October 1. The page gives no GA/Beta label.
• Cloud Migration Agent Skill updates: generates a read-only migration runbook for the whole project before changing code. New patterns include Classic UI/ExtJS/Coral 2 dialogs to Coral 3, static templates to editable templates, Guava cache to Caffeine, and Dispatcher config conversion from AMS or on-prem setups. These are AI-assisted aids, so review every change.

4. A sensible order of work

1. Find and remove deprecated API usage (Build Analyzer, dependency tree).
2. Confirm the pipeline passes the Code Quality step.
3. Once the SDK supports it, run your build and tests on Java 25 locally.
4. Opt in a dev environment in November, then staging, and keep the Java 21 rollback in mind.
5. Plan production well before the June 2027 forced migration.

Bottom line

The deprecated-API deadline is now a stability and support problem, not just a build warning. The Java 25 migration has a long runway, but only if you start validating before Adobe’s lower-environment migration begins in February 2027.

Has anyone already run a Java 25 build against the SDK? Libraries that broke, or any surprises in the Build Analyzer output, would be useful to hear.