import org.gjt.sp.jedit.buffer.FoldHandler;
import org.gjt.sp.jedit.ServiceManager;

String foldHandlerName = Macros.input(view, "Folding Mode:");
FoldHandler foldHandler = (FoldHandler)ServiceManager.getService("org.gjt.sp.jedit.buffer.FoldHandler", foldHandlerName);
if(foldHandler != null) {
	Buffer[] openBuffers = jEdit.getBuffers();
	int bufferCount = openBuffers.length;
	for(int index = 0; index < bufferCount; index++) {
		openBuffers[index].setFoldHandler(foldHandler);
	}
} else {
	Macros.message(view, "No fold handler found with name: " + foldHandlerName);
}