Real quick. Spent the past few hours working around some nasty issues with gradle and jenkins. It seems due to a bug, the jenkins gradle plugin puts the dependency/artifact cache under the jobs workspace. This really isn't a good idea as every job would then download all of the projects artifacts taking up large amounts of space. At the same time, I also needed to setup the proxy information for gradle, which sadly doesn't reuse the jenkins proxy information.
I was able to finally figure out a good place to define the gradle user home and proxy information in a single place to prevent each job from having to define it.
Go into Manage Jenkins > Configure System. Under Global properties check Environment variables and fill in the following for name and value:
name: GRADLE_OPTS
value: -Dgradle.user.home=/home/tomcat/.gradle -Dhttp.proxyHost=101.10.10.10 -Dhttp.proxyPort=3128
For the gradle.user.home property, I tried using ~/.gradle, but that didn't work which means most likely my $HOME environment variable was not set for whatever reason. My guess is it has something to do with all the troubles I've had lately using the bitnami jenkins amazon ami. I also tried setting the environment variable GRADLE_USER_HOME, but that didn't seem to work. Either way, hopefully this will help others.