This directory contains rules for linking in the right Eclipse jars into the build. To make this work, the eclipse_jars.bzl script contains the Eclipse SDK version to use and the pinned version ids of each Eclipse SDK jar. The Eclipse SDK jars are extracted from an Eclipse install and checked into the Git repo.
If you want to upgrade the SDK version that we use to build against, you will need to manually update all the versions in the eclipse_jars.bzl script. Yes, this is as painful as it sounds.