実行コマンド
docker build -t myjava:openjdk .
docker run -it --rm -v ${PWD}:/mnt myjava:openjdk javac Main.java
docker run -it --rm -v ${PWD}:/mnt myjava:openjdk java Mainもしくは
docker compose up -d
docker compose exec myjava javac Main.java
docker compose exec myjava java Main
docker compose down