I have created a node that holds MS office word document.( i have posted the exact question on stack overflow: jcr - Unable to retrieve versioned data of a node - Stack Overflow

                       VersionManager versionManager = session.getWorkspace().getVersionManager();

                        File wordFile = new File("DMS.docx");

                         Node documentNode = rootNode.addNode("Documents");

                         Node fileNode = documentNode.addNode(wordFile.getName(),"nt:file");

                         fileNode.addMixin("mix:versionable");

                         // Upload the file to that node ...

                         Node contentNode = fileNode.addNode("jcr:content", "nt:resource");

                         Binary binary = getFileBinary(wordFile);

                         contentNode.setProperty("jcr:data", binary);

                         session.save();

                         Version v1 =   versionManager.checkin(fileNode.getPath());

now i checkout the file through versionManager and update contents and  then check back in like below.

      fileNode = session.getRootNode().getNode("Documents").getNode(wordFile.getName());

       versionManager.checkout(fileNode.getPath());

        java.nio.file.Path path = Paths.get("DMSUpdated.docx");

                             if (!Files.exists(path)) {

                                 Files.createFile(path);

                             }

                             Files.write(path, "Text to be added".getBytes(), StandardOpenOption.APPEND);

                             Binary updatedBinary = getFileBinary(new File(filePath));

                             contentNode.setProperty("jcr:data", updatedBinary);

                             session.save();

    //check - in

     Version updatedVersion =   versionManager.checkin(fileNode.getPath());

Now i am trying to restore the node to updated version like below:

    Node finalFileNode =   session.getNode("/Documents").getNode(wordFile.getName());

              versionManager.restore(finalFileNode.getPath(),updatedVersion,false);

        Node finalContentNode = finalFileNode.getNode("jcr:content");

                     InputStream initialStream = finalContentNode.getProperty("jcr:data").getBinary().getStream();

                        byte[] buffer = new byte[initialStream.available()];

                        initialStream.read(buffer);

                          File updatedFile = new File("//TestFiles//FinalDMS.docx");

                        OutputStream outStream = new FileOutputStream(updatedFile);

                        outStream.write(buffer);

This gives me contents of version v1 and not updated version, not sure if i am doing something wrong?