add docker support 🐳

Dockerfile

@@ -0,0 +1,9 @@
+FROM maven:3-jdk-8-alpine as builder
+WORKDIR /app
+COPY . .
+RUN mvn package
+
+FROM java:8-jdk-alpine as runner
+WORKDIR /app
+COPY --from=builder /app/target/dddsample*.jar /app/
+CMD java -jar dddsample*.jar 

docker-compose.yml

@@ -0,0 +1,6 @@
+version: '3'
+services:
+    app:
+      build: .
+      ports:
+      - 8080