Prevent file channel from closing after reading xml file

For more detailed information regarding the motivation behind this goal (and my efforts to solve it) view my previous question. I decided to ask this as a new question entirely as I thought that it had evolved sufficiently to merit doing so. As a summary, I intend to use JDOM in combination with NIO in order to:

1. Gain an exclusive file lock on an xml file.


2. Read the file into a Document object.


3. Make arbitrary changes (with lock still active!).


4. Write the changes back to the xml file.


5. Release the file lock.

The issue which I am getting however is that the code to read the xml file into a document object closes the channel (and therefore releases the lock), as seen below:

import java.io.*;
import java.nio.channels.Channels;
import java.nio.channels.FileChannel;
import javax.xml.parsers.*;
import org.w3c.dom.Document;
import org.xml.sax.SAXException;

public class Test4{ 
    String path = "file.xml";
    private FileChannel channel;
    private DocumentBuilderFactory dbFactory;
    private DocumentBuilder dBuilder;
    private Document doc;

    public Test4(){
        try {
            channel = new RandomAccessFile(new File(path), "rw").getChannel();
            dbFactory = DocumentBuilderFactory.newInstance();
            dBuilder = dbFactory.newDocumentBuilder();

            System.out.println(channel.isOpen());
            doc = dBuilder.parse(Channels.newInputStream(channel));
            System.out.println(channel.isOpen());

            channel.close(); //Redundant
        } catch (IOException | ParserConfigurationException | SAXException e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args){
        new Test4();
    }
}

Output:

true
false

Having looked through the documentation and trawled the built in Java libraries, I am really struggling to even find where the channel is closed, let alone how to prevent it closing. Any pointers would be great! Thanks.