Outputting a document via JDOM

You can output a Document using an output tool, of which there are several standard ones available. The org.jdom.output.XMLOutputter tool is probably the most commonly used. It writes the document as XML to a specified OutputStream.
The SAXOutputter tool is another alternative. It generates SAX events based on the JDOM document, which you can then send to an application component that expects SAX events. In a similar manner, DOMOutputter creates a DOM document, which you can then supply to a DOM-receiving application component. The code to output a Document as XML looks like this:

XMLOutputter outputter = new XMLOutputter();
outputter.output(doc, System.out);

XMLOutputter takes parameters to customize the output. The first parameter is the indentation string; the second parameter indicates whether you should write new lines. For machine-to-machine communication, you can ignore the niceties of indentation and new lines for the sake of speed:

XMLOutputter outputter = new XMLOutputter("", false);
outputter.output(doc, System.out); 

Full Code:

import java.io.*;
import org.jdom.*;
import org.jdom.input.*;
import org.jdom.output.*;
public class PrettyPrinter {
   public static void main(String[] args) {
        // Assume filename argument
        String filename = args[0];
        try {
            // Build the document with SAX and Xerces, no validation
            SAXBuilder builder = new SAXBuilder();
            // Create the document
            Document doc = builder.build(new File(filename));
            // Output the document, use standard formatter
            XMLOutputter fmt = new XMLOutputter();
            fmt.output(doc, System.out);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}