e4b is an Eclipse plugin for Bazel. It is really rudimentary. It simply supports creating the classpath from a project and using Bazel for incremental builds..
You can create a new Bazel project with New project > Import Bazel project Then you can select the list of targets you want to build and the list of directories you want to track.
It is highly experimental and support is minimal. However, we are happy to accept contribution to make this support grows to a better shape.
Interesting feature to add is first to be able to launch test from Eclipse, correctly adding the eclipse debugger to the JVM.
Second, better support for BUILD file would be interesting. Maybe using Xtext.
Finally, the code is completely missing tests and improving the test coverage would be great.