Search for java on Docker Hub and the official image is the top hit, but open the page at https://hub.docker.com/_/java and you will see it's been deprecated.
That means the java image (and the openjdk image which replaced it) are no longer being maintained. The images are old, so you should avoid them.
There are a few alternatives with active maintainers (e.g. Amazon and IBM). My preference is for eclipse-temurin which is an open-source build of OpenJDK.
You might start by copying the command from the Docker Hub page, which will download the default image:
docker pull eclipse-temurin
Run a container to check the Java version:
docker run eclipse-temurin java -version
The output will show the OpenJDK and JRE versions
Check the tags page on Docker Hub and search for alpine and you'll see there are JRE and IDK versions.
The JRE build for Alpine is the smallest - the tag contains the version number, so this pulls a small JRE image for OpenJDK 23:
docker pull eclipse-temurin:23-jre-alpine
Check the sizes:
docker image ls eclipse-temurin
Your output may be different, but mine shows the default ("latest") image is 478MB; Alpin JRE is 206MB...
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