Changed docker files to multistage reducing JDK 11 image by 28% and S…

…erver JRE 8 by 18% (oracle#1467)

OracleJava/java-11/Dockerfile

@@ -1,48 +1,78 @@
 # Copyright (c) 2019 Oracle and/or its affiliates. All rights reserved.
 #
 # Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl.
+#
+# ORACLE DOCKERFILES PROJECT
+# --------------------------
+# This is the Dockerfile for Oracle JDK 11
+#
+# REQUIRED FILES TO BUILD THIS IMAGE
+# ----------------------------------
+#
+# (1) jdk-11.XX_linux-x64_bin.tar.gz
+#     Download from https://www.oracle.com/technetwork/java/javase/downloads/jdk11-downloads-5066655.html
+#
+# HOW TO BUILD THIS IMAGE
+# -----------------------
+# Put all downloaded files in the same directory as this Dockerfile
+# Run:
+#      $ docker build -t oracle/jdk:11 ..
+#
+# This command is already scripted on build.sh so you can alternatively run
+#		$ bash build.sh
 
-FROM oraclelinux:7-slim
+# The builder image will be use to uncompress the tar.gz file with the Java Runtime.
+
+FROM oraclelinux:7-slim as builder
 
 MAINTAINER Aurelio Garcia-Ribeyro <[email protected]>
 
 RUN set -eux; \
 	yum install -y \
 		gzip \
 		tar \
-# JDK assumes freetype is available		
-		freetype fontconfig \
 	; \
 	rm -rf /var/cache/yum
 
-
 # Default to UTF-8 file.encoding
 ENV LANG en_US.UTF-8
 
 
-# Download the JDK from
-#
-#  - https://www.oracle.com/technetwork/java/javase/downloads/jdk11-downloads-5066655.html
-#	
-# and place it on the same directory as the Dockerfile
-#
+# Environment variables for the builder image.  
+# Required to validate that you are using the correct file
 
-ENV JAVA_VERSION=11.0.5 \
-	JAVA_PKG=jdk-11.0.5_linux-x64_bin.tar.gz \
+ENV JAVA_PKG=jdk-11.0.5_linux-x64_bin.tar.gz \
 	JAVA_SHA256=387e60bdad6d6fc20d41cd712536f0f7adbb086fa73bc3cb225b3edad0bfa0a6 \
 	JAVA_HOME=/usr/java/jdk-11
-
-ENV	PATH $JAVA_HOME/bin:$PATH
 
 ##
 COPY $JAVA_PKG /tmp/jdk.tgz
 RUN set -eux; \
-	\
 	echo "$JAVA_SHA256 */tmp/jdk.tgz" | sha256sum -c -; \
 	mkdir -p "$JAVA_HOME"; \
 	tar --extract --file /tmp/jdk.tgz --directory "$JAVA_HOME" --strip-components 1; \
-	rm /tmp/jdk.tgz; \
-	\
+	rm /tmp/jdk.tgz; 
+
+## Get a fresh version of SLIM for the final image	
+FROM oraclelinux:7-slim
+
+# Default to UTF-8 file.encoding
+ENV LANG en_US.UTF-8
+
+ENV JAVA_VERSION=11.0.5 \
+	JAVA_HOME=/usr/java/jdk-11
+
+ENV	PATH $JAVA_HOME/bin:$PATH	
+
+# Copy the uncompressed Java Runtime from the builder image
+COPY --from=builder $JAVA_HOME $JAVA_HOME
+
+RUN set -eux; \
+	yum install -y \
+# JDK assumes freetype is available		
+		freetype fontconfig \
+	; \
+	rm -rf /var/cache/yum; \
 	ln -sfT "$JAVA_HOME" /usr/java/default; \
 	ln -sfT "$JAVA_HOME" /usr/java/latest; \
 	for bin in "$JAVA_HOME/bin/"*; do \

OracleJava/java-8/Dockerfile

@@ -1,11 +1,33 @@
 # Copyright (c) 2019 Oracle and/or its affiliates. All rights reserved.
 #
 # Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl.
+#
+# ORACLE DOCKERFILES PROJECT
+# --------------------------
+# This is the Dockerfile for Oracle Server JRE 8
+#
+# REQUIRED FILES TO BUILD THIS IMAGE
+# ----------------------------------
+#
+# (1) server-jre-8uXX-linux-x64.tar.gz
+#     Download from http://www.oracle.com/technetwork/java/javase/downloads/server-jre8-downloads-2133154.html
+#
+# HOW TO BUILD THIS IMAGE
+# -----------------------
+# Put all downloaded files in the same directory as this Dockerfile
+# Run:
+#      $ docker build -t oracle/serverjre:8 .
+#
+# This command is already scripted on build.sh so you can alternatively run
+#		$ bash build.sh
 
-FROM oraclelinux:7-slim
+# The builder image will be use to uncompress the tar.gz file with the Java Runtime.
+
+FROM oraclelinux:7-slim as builder
 
 MAINTAINER Aurelio Garcia-Ribeyro <[email protected]>
 
+# Since the files is compressed as tar.gz first yum install gzip and tar
 RUN set -eux; \
 	yum install -y \
 		gzip \
@@ -17,38 +39,46 @@ RUN set -eux; \
 # Default to UTF-8 file.encoding
 ENV LANG en_US.UTF-8
 
+# Environment variables for the builder image.  
+# Required to validate that you are using the correct file
 
-# Download the JDK from
-#
-#  https://www.oracle.com/technetwork/java/javase/downloads/server-jre8-downloads-2133154.html
-#	
-# and place it on the same directory as the Dockerfile
-#
-
-ENV JAVA_VERSION=1.8.0_231 \
-	JAVA_PKG=server-jre-8u231-linux-x64.tar.gz \
+ENV JAVA_PKG=server-jre-8u231-linux-x64.tar.gz \
 	JAVA_SHA256=1d59a0ea3ef302d5851370b838693b0b6bde4c3f32015a4de0a9e4d202a988fc \
 	JAVA_HOME=/usr/java/jdk-8
-
-ENV	PATH $JAVA_HOME/bin:$PATH
 
-##
 COPY $JAVA_PKG /tmp/jdk.tgz
 RUN set -eux; \
-	\
 	echo "$JAVA_SHA256 */tmp/jdk.tgz" | sha256sum -c -; \
 	mkdir -p "$JAVA_HOME"; \
 	tar --extract --file /tmp/jdk.tgz --directory "$JAVA_HOME" --strip-components 1; \
-	rm /tmp/jdk.tgz; \
-	\
-	ln -sfT "$JAVA_HOME" /usr/java/default; \
+	rm /tmp/jdk.tgz
+
+## Get a fresh version of SLIM for the final image
+
+FROM oraclelinux:7-slim
+
+# Default to UTF-8 file.encoding
+ENV LANG en_US.UTF-8
+
+ENV JAVA_VERSION=1.8.0_231 \
+	JAVA_HOME=/usr/java/jdk-8 
+
+ENV	PATH $JAVA_HOME/bin:$PATH
+
+# Copy the uncompressed Java Runtime from the builder image
+COPY --from=builder $JAVA_HOME $JAVA_HOME
+
+##
+RUN	ln -sfT "$JAVA_HOME" /usr/java/default; \
 	ln -sfT "$JAVA_HOME" /usr/java/latest; \
 	for bin in "$JAVA_HOME/bin/"*; do \
 		base="$(basename "$bin")"; \
 		[ ! -e "/usr/bin/$base" ]; \
 		alternatives --install "/usr/bin/$base" "$base" "$bin" 20000; \
 	done; \
 # -Xshare:dump will create a CDS archive to improve startup in subsequent runs	
+# the file will be stored as /usr/java/jdk-8/jre/lib/amd64/server/classes.jsa 
+# See https://docs.oracle.com/javase/8/docs/technotes/guides/vm/class-data-sharing.html
 	java -Xshare:dump; \
 	java -version; \
 	javac -version