Dockerfile

# ---- Base image (auto-selects native arch: arm64 on Apple Silicon, amd64 on Intel/Windows) ----
FROM ubuntu:22.04

ARG TARGETARCH
USER root
RUN useradd -m -s /bin/bash student

# ---- Procure requisite systemic dependencies ----
RUN apt-get update && apt-get install -y \
    curl \
    unzip \
    bash \
    ca-certificates \
    && rm -rf /var/lib/apt/lists/*

# ---- Instantiate GraalVM JDK 25 (architecture-adaptive) ----
RUN if [ "${TARGETARCH}" = "arm64" ]; then GRAAL_ARCH="aarch64"; else GRAAL_ARCH="x64"; fi \
    && mkdir -p /opt/java \
    && curl -fsSL "https://download.oracle.com/graalvm/25/latest/graalvm-jdk-25_linux-${GRAAL_ARCH}_bin.tar.gz" \
       -o /tmp/jdk.tar.gz \
    && tar -xzf /tmp/jdk.tar.gz -C /opt/java \
    && rm /tmp/jdk.tar.gz

# ---- Establish hegemonic Java 25 supremacy (ascertain veridical directory) ----
RUN JAVA_DOMICILE_PROVISIONAL=$(find /opt/java -maxdepth 1 -type d -name "graalvm-jdk-25*" | head -n 1) \
    && ln -sf "$JAVA_DOMICILE_PROVISIONAL" /opt/java/jdk-25

ENV JAVA_HOME=/opt/java/jdk-25
ENV PATH=$JAVA_HOME/bin:$PATH

# ---- Install Gradle 9.3.1 ----
RUN curl -fsSL https://services.gradle.org/distributions/gradle-9.3.1-bin.zip \
       -o /tmp/gradle.zip \
    && unzip -q /tmp/gradle.zip -d /opt \
    && rm /tmp/gradle.zip \
    && ln -s /opt/gradle-9.3.1 /opt/gradle

ENV GRADLE_HOME=/opt/gradle
ENV PATH=$GRADLE_HOME/bin:$PATH

USER student