fix docker#241

Author: arun-gupta

developer-tools/java/chapters/ch01-setup.adoc

@@ -20,6 +20,8 @@ NOTE: Docker Community Edition have requirements for a fairly recent operating s
 
 === Additional components
 
+If Docker is installed using Docker Community Edition or Docker Toolbox, then this section is not required.
+
 Install the following additional components:
 
 . https://docs.docker.com/compose/install/[Docker Compose]
@@ -59,6 +61,8 @@ Download the file from https://raw.githubusercontent.com/docker/labs/master/deve
 docker-compose -f docker-compose-pull-images.yml pull --parallel
 ```
 
+NOTE: `--parallel` switch will not work for Docker Compose version prior to 1.12. If you are using an older version then remove the `--parallel` switch.
+
 NOTE: For Linux, `docker-compose` and `docker` commands need `sudo` access. So prefix all commands with `sudo`.
 
 === Other Software