fix(spark): remove the JRE before installing the JDK (#1410)

* fix(spark): remove the JRE before installing the JDK

* english

Author: razvan

CHANGELOG.md

@@ -53,6 +53,7 @@ All notable changes to this project will be documented in this file.
 - zookeeper: Remove `3.9.3` ([#1401]).
 - trino: Remove `451` and `476` ([#1403]).
 - hbase: Remove `2.6.2` ([#1408]).
+- spark: remove the JRE before installing the JDK to prevent version conflicts ([#1410]).
 
 ### Fixed
 
@@ -87,6 +88,7 @@ All notable changes to this project will be documented in this file.
 [#1406]: https://github.com/stackabletech/docker-images/pull/1406
 [#1408]: https://github.com/stackabletech/docker-images/pull/1408
 [#1409]: https://github.com/stackabletech/docker-images/pull/1409
+[#1410]: https://github.com/stackabletech/docker-images/pull/1410
 
 ## [25.11.0] - 2025-11-07
 

spark-k8s/Dockerfile.3

@@ -176,8 +176,6 @@ chmod -R g=u /stackable/spark-${PRODUCT_VERSION}-stackable${RELEASE_VERSION}/ass
 chmod -R g=u /stackable/jmx
 EOF
 
-# TODO: java-base installs the Adoptium dnf repo and the Termurin jre which is not needed here.
-# To reduce the size of this image, the Adoptium repo could be moved to stackable-base instead.
 FROM local-image/java-base AS final
 
 ARG PRODUCT_VERSION
@@ -218,6 +216,11 @@ COPY --chown=${STACKABLE_USER_UID}:0 spark-k8s/licenses /licenses
 RUN <<EOF
 microdnf update
 
+# Remove the JRE that was installed by local-image/java-base.
+# The JRE is not enough for Spark because some functionality requires the JDK.
+# Also having both JRE and JDK installed causes conflicts with Java 21 because they have slightly different versions in the Adoptium repository.
+microdnf remove "temurin-${JAVA_VERSION}-jre"
+
 # procps:
 #    Required for spark startup scripts.
 # temurin-{version}-jdk:

spark-k8s/Dockerfile.4

@@ -150,8 +150,6 @@ chmod -R g=u /stackable/spark-${PRODUCT_VERSION}-stackable${RELEASE_VERSION}/ass
 chmod -R g=u /stackable/jmx
 EOF
 
-# TODO: java-base installs the Adoptium dnf repo and the Termurin jre which is not needed here.
-# To reduce the size of this image, the Adoptium repo could be moved to stackable-base instead.
 FROM local-image/java-base AS final
 
 ARG PRODUCT_VERSION
@@ -190,6 +188,11 @@ COPY --chown=${STACKABLE_USER_UID}:0 spark-k8s/licenses /licenses
 RUN <<EOF
 microdnf update
 
+# Remove the JRE that was installed by local-image/java-base.
+# The JRE is not enough for Spark because some functionality requires the JDK.
+# Also having both JRE and JDK installed causes conflicts with Java 21 because they have slightly different versions in the Adoptium repository.
+microdnf remove "temurin-${JAVA_VERSION}-jre"
+
 # procps:
 #    Required for spark startup scripts.
 # temurin-{version}-jdk: