Adding README for java calculator. #11

	name: Update Docker Image Reference on PR

	on:
	pull_request:
	paths:
	- 'templated_tests/**'
	push:
	branches:
	- main
	paths:
	- 'templated_tests/**'

	jobs:
	changed-files:
	runs-on: ubuntu-latest
	outputs:
	matrix: ${{ steps.changed-files.outputs.all_changed_files }}
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0

	- name: Get changed files
	id: changed-files
	uses: tj-actions/changed-files@v44
	with:
	matrix: true
	dir_names: true
	files: \|
	templated_tests/*/

	build-and-push-image:
	needs: changed-files
	runs-on: ubuntu-latest
	strategy:
	fail-fast: false
	matrix:
	files: ${{fromJson(needs.changed-files.outputs.matrix)}}
	permissions:
	contents: read
	packages: write

	steps:
	- name: Checkout repository
	uses: actions/checkout@v2

	- name: Log in to DockerHub
	uses: docker/login-action@v1
	with:
	username: ${{ secrets.DOCKERHUB_USERNAME }}
	password: ${{ secrets.DOCKERHUB_TOKEN }}

	- name: Get Docker image name
	id: image_name
	run: \|
	image_name=$(echo ${{ matrix.files }} \| sed 's/templated_tests\///')
	echo "::set-output name=image_name::${{ secrets.DOCKERHUB_USERNAME }}/$image_name"

	- name: Docker metadata
	id: meta
	uses: docker/metadata-action@v5
	with:
	images: ${{ steps.image_name.outputs.image_name }}
	tags: \|
	type=raw,value={{sha}},event=pr
	type=raw,value=latest,enable={{is_default_branch}}

	- name: Build and push Docker image to DockerHub
	uses: docker/build-push-action@v6
	with:
	context: ${{ matrix.files }}
	push: true
	tags: ${{ steps.meta.outputs.tags }}

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