Add Java Options

Added variable to pass Java options to the container.
Removed single quotes in comments that were carried from the jenkinsci
Dockerfile as they cause the command to be executed, causing confusing
errors to occur in stdout.

Change-Id: Icf68bc38b75fb06570b6cbbd139125d7a104a4c2
Signed-off-by: Alanny Lopez <Alanny.Lopez@ibm.com>
diff --git a/build-jenkins.sh b/build-jenkins.sh
index 5eecd06..91f032e 100755
--- a/build-jenkins.sh
+++ b/build-jenkins.sh
@@ -19,10 +19,12 @@
 #                     Default: "", variable ignored by default
 #  cont_import_mnt    The directory on the container used to import extra files
 #                     Default: "/mnt/jenkins_import", will be ignored by default
-#  options            What will be passed as the environment variable for the
+#  jenkins_options    What will be passed as the environment variable for the
 #                     JENKINS_OPTS environment variable.
 #                     Default: "--prefix=/jenkins"
-#
+#  java_options       What will be passed as the environment variable for the
+#                     JAVA_OPTS environment variable.
+#                     Default: "-Xmx4096m"
 # Build Variables:
 #  img_tag            The tag for the OpenJDK image used to build the Dockerfile
 #                     Default: "/8-jdk"
@@ -59,7 +61,8 @@
 home_mnt=${home_mnt:-${workspace}/jenkins_home}
 host_import_mnt=${host_import_mnt:-}
 cont_import_mnt=${cont_import_mnt:-/mnt/jenkins_import}
-options="--prefix=/jenkins"
+jenkins_options=${jenkins_options:-"--prefix=/jenkins"}
+java_options=${java_options:-"-Xmx4096m"}
 
 # Dockerfile Variables
 img_tag=${img_tag:-8-jdk}
@@ -118,7 +121,7 @@
 ENV JENKINS_HOME ${j_home}
 ENV JENKINS_SLAVE_AGENT_PORT ${agent_port}
 
-# Jenkins will default to run with user `jenkins`, uid = 1000
+# Jenkins will default to run with user jenkins, uid = 1000
 # If you bind mount a volume from the host or a data container,
 # ensure you use the same uid
 RUN groupadd -g ${j_gid} ${j_group} && \
@@ -128,7 +131,7 @@
 # can be persisted and survive image upgrades
 VOLUME ${j_home}
 
-# `/usr/share/jenkins/ref/` contains all reference configuration we want
+# /usr/share/jenkins/ref/ contains all reference configuration we want
 # to set on a fresh new installation. Use it to bundle additional plugins
 # or config file with your custom jenkins Docker image.
 RUN mkdir -p /usr/share/jenkins/ref/init.groovy.d
@@ -161,7 +164,7 @@
 COPY jenkins.sh /usr/local/bin/jenkins.sh
 ENTRYPOINT ["/bin/tini", "--", "/usr/local/bin/jenkins.sh"]
 
-# from a derived Dockerfile, can use `RUN plugins.sh active.txt` to setup /usr/share/jenkins/ref/plugins from a support bundle
+# from a derived Dockerfile, can use RUN plugins.sh active.txt to setup /usr/share/jenkins/ref/plugins from a support bundle
 COPY plugins.sh /usr/local/bin/plugins.sh
 COPY install-plugins.sh /usr/local/bin/install-plugins.sh
 
@@ -240,7 +243,8 @@
     -v ${home_mnt}:${j_home} \
     -p ${http_port}:8080 \
     -p ${agent_port}:${agent_port} \
-    --env JENKINS_OPTS=\"${options}\" \
+    --env JAVA_OPTS=\"${java_options}\" \
+    --env JENKINS_OPTS=\"${jenkins_options}\" \
     ${out_img}
 
 elif [[ ${launch} == "k8s" ]]; then