Adding a Dockerfile. #21

	name: Java build (for branches)

	on:
	push:
	branches: [ master ]

	jobs:
	# JDK8 build without Sonar, because Sonar requires JDK11 and we don't need to run Sonar on all JDKs anyway
	build8:
	name: Build on JDK 8

	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v2
	- name: Set up JDK 8
	uses: actions/setup-java@v1
	with:
	java-version: 8
	- name: Cache Maven packages
	uses: actions/cache@v1
	with:
	path: ~/.m2
	key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml') }}
	restore-keys: ${{ runner.os }}-m2
	- name: Build with Maven
	run: mvn -B clean verify -DCI=true
	working-directory: ./source

	# JDK11 build with Sonar
	build11:
	name: Build on JDK 11

	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v2
	with:
	fetch-depth: 0 # Shallow clones are disabled for a better relevancy of analysis
	- name: Set up JDK 11
	uses: actions/setup-java@v1
	with:
	java-version: 11
	- name: Cache SonarCloud packages
	uses: actions/cache@v1
	with:
	path: ~/.sonar/cache
	key: ${{ runner.os }}-sonar
	restore-keys: ${{ runner.os }}-sonar
	- name: Cache Maven packages
	uses: actions/cache@v1
	with:
	path: ~/.m2
	key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml') }}
	restore-keys: ${{ runner.os }}-m2
	- name: Build and analyze
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }} # Needed to get PR information, if any
	SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
	run: mvn -B clean verify org.sonarsource.scanner.maven:sonar-maven-plugin:sonar -Dsonar.projectKey=The4thLaw_demyo -DCI=true -Pvue,coverage,dev
	working-directory: ./source

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