Need
I want to import Buildship into gradle project dependencies from maven repository, then manually convert gradle project to eclipse project and then compile by ECJ of eclipse project.
Can you elaborate a bit more on what you are trying?
At least to me it is not really clear.
Buildship is the Eclipse plugin for integration of Gradle builds, so that you can properly work with Gradle builds from within Eclipse for those insisting on using it.
Why do you want to depend on Buildship in your project and what do you then want to do?