How do i update an existing XML File?

Question

Hello, I have the following xml file gps.xml:<?xml version="1.0"?>
<!DOCTYPE gps SYSTEM "gps.dtd">
<gps>
   <latitude>43.00000</latitude>
   <longitude>-83.00000</longitude>
</gps> I already have methods written to get the values. But how can I change these values and update the file to reflect these changes?
thanks for your help!

Answer 1

Hi, I already have this following code. I would just like to add a method to it to update the existing XML file with different lat/lon coordinates. Could you please help me out with it? thanks
import java.io.*;
import java.io.PrintWriter;
import java.net.MalformedURLException;
import java.net.URL;
import javax.xml.parsers.*;
import org.w3c.dom.*;
import org.xml.sax.*;
public class Gps implements java.io.Serializable {
    private double latitude_;
    private double longitude_;
    public Gps(Document doc) {
        setup(doc.getDocumentElement());
    public Gps(String uri) throws IOException, SAXException, ParserConfigurationException {
        setup(uri);
    public void setup(Document doc) {
        setup(doc.getDocumentElement());
    public void makeElement(Node parent) {
        Document doc;
        if (parent instanceof Document) {
            doc = (Document)parent;
        } else {
            doc = parent.getOwnerDocument();
        Element element = doc.createElement("gps");
        int size;
        URelaxer.setElementPropertyByDouble(element, "latitude", this.latitude_);
        URelaxer.setElementPropertyByDouble(element, "longitude", this.longitude_);
        parent.appendChild(element);
     public Document makeDocument() throws ParserConfigurationException {
        Document doc = UJAXP.makeDocument();
        makeElement(doc);
        return (doc);
    public final double getLatitude() {
        return (latitude_);
    public final void setLatitude(double latitude) {
        this.latitude_ = latitude;
    public final double getLongitude() {
        return (longitude_);
    public final void setLongitude(double longitude) {
        this.longitude_ = longitude;
   public final void updateXmlFile(double latitude, double longitude) {
     // something???
    public final void updateXmlFile(double latitude, double longitude) {
        this.latitude_ = latitude;
        this.longitude_ = longitude;
    public String makeTextDocument() {
        StringBuffer buffer = new StringBuffer();
        makeTextElement(buffer);
        return (new String(buffer));
    public void makeTextElement(StringBuffer buffer) {
        int size;
        buffer.append("<gps");
        buffer.append(">");
        buffer.append("<latitude>");
        buffer.append(Double.toString(getLatitude()));
        buffer.append("</latitude>");
        buffer.append("<longitude>");
        buffer.append(Double.toString(getLongitude()));
        buffer.append("</longitude>");
        buffer.append("</gps>");
    public String toString() {
        try {
            return (makeTextDocument());
        } catch (Exception e) {
            return (super.toString());
}