What are some R packages that link or integrate Rstudio with Java?

The one I’ve been using and works fairy well is Rserve package.

I have been using it to run R code by executing Java code in Eclipse IDE. For example for visualizing data.

Here is the documentation Rserve - Binary R server - RForge.net (https://www.rforge.net/Rserve/doc.html) . Once that you install Rserve you have to run Rserve on Rstudio. This works as a kind of server. Now you are able to run R code from inside Java code directly from the Java IDE you are using.

Here are some code examples : Rserve - Binary R server - RForge.net (https://www.rforge.net/Rserve/example.html)
There should be other packages -as suggested in the existing answers- which do the same thing but by using Rserve seems more straight-forward to me.

This post is also my answer to the question you see as a title on Quora. Here the link to it https://www.quora.com/What-are-some-R-packages-that-link-or-integrate-R-with-Java/answer/Alket-Cecaj