build: upgrade Java source/target compatibility from 8 to 11 (#610)

* build: upgrade Java source/target compatibility from 8 to 11

Java 11 migration has been planned since 2020 (datahub-project/datahub#1699)
but was blocked by LinkedIn internally still being on Java 8. That blocker
no longer applies — downstream consumers like metadata-graph-assets and
metadata-models have moved to Java 17, and metadata-crawlers is on Java 11.

This also unblocks a future Elasticsearch upgrade from 7.17.24 to 8.x,
which is needed to resolve long-standing ELR validation failures due to
CVEs in the ES 7.17.24 dependency (failing since June 2025).

Changes:
- Set sourceCompatibility/targetCompatibility to 11 in root build.gradle
- Update developer docs and roadmap to reflect Java 11 requirement

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* ci: update CI workflows to use JDK 11

Update build-and-test workflow and release action to use JDK 11
instead of JDK 8, matching the new source/target compatibility.
Also upgrade actions/setup-java from v1 to v3.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* ci: revert unnecessary setup-java addition in release action

The release action uses the runner's default JDK which is already
11+, so explicit setup is not needed.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: mridul111998

.github/workflows/build-and-test.yml

@@ -20,10 +20,11 @@ jobs:
     runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v2
-      - name: Set up JDK 1.8
-        uses: actions/setup-java@v1
+      - name: Set up JDK 11
+        uses: actions/setup-java@v3
         with:
-          java-version: 1.8
+          java-version: '11'
+          distribution: 'temurin'
       - name: Install lib
         run: sudo apt-get install libncurses5
 

CLAUDE.md

@@ -9,7 +9,7 @@ platform. It provides type-safe, schema-driven metadata management with event-dr
 storage backends (SQL via Ebean, Elasticsearch for search). Built on LinkedIn's Pegasus data framework and Rest.li for
 REST APIs.
 
-**Java version**: 1.8 (Java 8) — required, newer versions will cause build failures.
+**Java version**: 11 (Java 11) — minimum required version.
 
 ## Build Commands
 

build.gradle

@@ -139,8 +139,8 @@ subprojects { sp ->
 
   afterEvaluate {
     if (project.plugins.hasPlugin('java')) {
-      sourceCompatibility = 1.8
-      targetCompatibility = 1.8
+      sourceCompatibility = 11
+      targetCompatibility = 11
     }
   }
 

docs/developers.md

@@ -56,20 +56,13 @@ For consistency please import and auto format the code using
 
 ### Getting `Unsupported class file major version 57`
 
-You're probably using a Java version that's too new for gradle. Run the following command to check your Java version
+You're probably using a Java version that's too new for Gradle. Gradle 6.9.4 supports up to JDK 16. Run the following
+command to check your Java version
 
 ```
 java --version
 ```
 
-While it may be possible to build and run DataHub using newer versions of Java, we currently only support
-[Java 1.8](https://www.oracle.com/java/technologies/javase/javase-jdk8-downloads.html) (aka Java 8). Plan for Java 11
-migration is being discussed in [this issue](https://github.com/linkedin/datahub/issues/1699).
-
-### Getting `cannot find symbol` error for `javax.annotation.Generated`
-
-Similar to the previous issue, please use Java 1.8 to build the project.
-
-You can install multiple version of Java on a single machine and switch between them using the `JAVA_HOME` environment
-variable. See [this document](https://docs.oracle.com/cd/E21454_01/html/821-2531/inst_jdk_javahome_t.html) for more
-details.
+This project requires [Java 11](https://adoptium.net/) or later to build. If you have multiple JDK versions installed,
+you can switch between them using the `JAVA_HOME` environment variable. See
+[this document](https://docs.oracle.com/cd/E21454_01/html/821-2531/inst_jdk_javahome_t.html) for more details.

docs/roadmap.md

@@ -39,7 +39,7 @@ Status: **Draft**
 - [ ] Enable `werror` for all Java code.
 - [ ] Remove use of tuples library (not idiomatic Java - replace with helper classes / POJOs).
 - [x] Elasticsearch 7 support.
-- [ ] Java 11 support.
+- [x] Java 11 support.
 
 ---