I am using persevere for an application I am writing that controls remote hardwere. Persevere is written in Java and doesn't supply an alternative API.
I am using a web-based GUI as the control panel. So far, so good.
I can get and set data using REST channels like dojo does but the problem is that I don't really know how to use REST channels. Which library should I use to do so?
If you use gcc as your toolchain you can embed a JVM with GCJ to run persevere inside your application. GCJ makes it easy to call C++ from Java with it's CNI interface (much easier than JNI). I used that method to use Java scripting inside our C++ application. You can even compile the persevere jar into a native library and link it to your app with GCJ.
The best reference is the GCJ Documentation.
There is also a Linux Journal contains the article Embedded Java with GCJ that you can read.
You can also study applications that use gcj.