Dockerfile to install maven

maven.Dockerfile

#
# Oracle Java 7 Dockerfile
#
# https://github.com/dockerfile/java
# https://github.com/dockerfile/java/tree/master/oracle-java7
#

# Pull base image.
FROM alpine as build

ARG MAVEN_VERSION=3.6.3
ARG USER_HOME_DIR="/root"
ARG BASE_URL=https://apache.osuosl.org/maven/maven-3/${MAVEN_VERSION}/binaries


# Install Java.
RUN apk --update --no-cache add openjdk7 curl

RUN mkdir -p /usr/share/maven /usr/share/maven/ref \
 && curl -fsSL -o /tmp/apache-maven.tar.gz ${BASE_URL}/apache-maven-${MAVEN_VERSION}-bin.tar.gz \
 && tar -xzf /tmp/apache-maven.tar.gz -C /usr/share/maven --strip-components=1 \
 && rm -f /tmp/apache-maven.tar.gz \
 && ln -s /usr/share/maven/bin/mvn /usr/bin/mvn

ENV MAVEN_HOME /usr/share/maven
ENV MAVEN_CONFIG "$USER_HOME_DIR/.m2"

# Define working directory.
WORKDIR /data

# Define commonly used JAVA_HOME variable
ENV JAVA_HOME /usr/lib/jvm/default-jvm/

# Define default command.
CMD ["mvn", "--version"]



# Spring docker sample
# FROM openjdk:8-jdk-alpine
# VOLUME /tmp
# ARG JAR_FILE
# COPY ${JAR_FILE} app.jar
# ENTRYPOINT ["java","-Djava.security.egd=file:/dev/./urandom","-jar","/app.jar"]

This is a sketch script. You can improve it using many techniques. I suggest you use env vars or a script that automates versioning as needed for your code base. And not least, be kind!
@Haarolean

@LuanComputacao sorry if I offended your sketch or you personally. Didn't seem sketchy enough for me, and considering that it's the core feature of this sketch, I find it lacking flexibility if I need to update my dockerfile every week or so.

For the ones not wishing to manually replace maven version in a dockerfile every time a new release is out (since the repo used in this dockerfile deletes the old packages once the new is out), here's my take on automatically downloading the latest stable maven version:
https://gist.github.com/Haarolean/a2a8acf07dfd60cbd68bfdfd20ca9195
Cheers