Use adoptopenjdk base image

Author: tsegismont

README.adoc

@@ -67,7 +67,7 @@ endif::env-github[]
 The Docker build has two stages:
 
 . Building the Maven project inside a `maven:3.6.3-openjdk-11` container
-. Copying the output of the build in a `openjdk:11-slim` container and configuring the entry point
+. Copying the output of the build in a `adoptopenjdk:11-jre-hotspot` container and configuring the entry point
 
 The benefits of this approach are:
 
@@ -128,7 +128,7 @@ endif::env-github[]
 The Docker build has two stages:
 
 . Building the Gradle project inside a `gradle:6.8.3-jdk11` container
-. Copying the output of the build in a `openjdk:11-slim` container and configuring the entry point
+. Copying the output of the build in a `adoptopenjdk:11-jre-hotspot` container and configuring the entry point
 
 The benefits of this approach are:
 

docker-gradle/Dockerfile

@@ -5,7 +5,7 @@ COPY . /project/
 RUN gradle assemble --no-daemon
 
 # 2nd Docker build stage: copy builder output and configure entry point
-FROM openjdk:11-slim
+FROM adoptopenjdk:11-jre-hotspot
 ENV APP_DIR /application
 ENV APP_FILE container-uber-jar.jar
 
@@ -15,4 +15,4 @@ WORKDIR $APP_DIR
 COPY --from=builder /project/build/libs/*-fat.jar $APP_DIR/$APP_FILE
 
 ENTRYPOINT ["sh", "-c"]
-CMD ["exec", "java", "-jar", "$APP_FILE"]
+CMD ["exec java -jar $APP_FILE"]

docker-maven/Dockerfile

@@ -5,7 +5,7 @@ COPY . /project/
 RUN mvn package -DskipTests -B
 
 # 2nd Docker build stage: copy builder output and configure entry point
-FROM openjdk:11-slim
+FROM adoptopenjdk:11-jre-hotspot
 ENV APP_DIR /application
 ENV APP_FILE container-uber-jar.jar