Clone this repository to Engine/Plugins/Developer in your UnrealEngine directory.
Now rebuild the engine (or better, build the plugin).
Add the following to the file Engine/Config/Linux/LinuxEngine.ini
(Keep in mind that Linux in that filepath might change to whatever OS you are using)
[/Script/SourceCodeAccess.SourceCodeAccessSettings]
PreferredAccessor=EclipseSourceCodeAccessor
In order to be able to find eclipse, some default paths are checked (like e.g. /usr/bin/eclipse).
In addition to that you also can export the environment variable UE4_ECLIPSE_BINARY with the full path to the eclipse binary.
This plugin should work on Linux, Win32, Win64 and Mac.
Based on the qt creator source access implementation and the included code lite source accessor.