JAVA, TWITTER, GOOGLE MAPS, XML

Question

the task:
Java command-line application that user enter location name and programm search using Twitter API the last messages, sent from the location. For example:
search.twitter.com/sea...54472,10km
messages must be in 4 varieties:
1.without sorting
2.sorting by name
3.sorting by date
4.sorting by content
For getting place coordinates using google maps api(XML or CSV).
To create places.csv, where store getting data about place from google maps (using cache).
file places.csv must consist from the string:
place name, xcoord, ycoord, radius_km, alternative name1..., alternative nameN

Answer 1

that`s what I have written
package tw;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.text.DecimalFormat;
import java.text.MessageFormat;
import java.text.NumberFormat;
import java.text.SimpleDateFormat;
import java.util.Collections;
import java.util.Comparator;
import java.util.Date;
import java.util.List;
import java.util.Locale;
import java.util.TimeZone;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.w3c.dom.Element;
class Map {
public String town;
public String sort;
class Geocoder {
public double x;
public double y;
class Twpost {
public Date date;
public String content;
public String author;
class TwpostComparator implements Comparator<Twpost> {
private String point;
public TwpostComparator(String field) {
this.point = point;
public int compare(Twpost post1, Twpost post2) {
if(point.equals("name")) {
return post1.author.compareTo(post2.author);
else if(point.equals("date")) {
return post1.date.compareTo(post2.date);
else if (point.equals("content")) {
return post1.content.compareTo(post2.content);
return 0;
public class Tw {
public static final String GOOGLE_MAPS_URL = "http://maps.google.com/maps/geo?output=csv&q={0}";
public static final String TWITTER_URL = "http://search.twitter.com/search.atom?geocode={0},{1},{2}km";
public static final String OUTPUT_DATE_PATTERN = "dd.MM.yyyy";
public static final int TWITTER_SEARCH_RADIUS = 10;
* @param args
//Main program that takes a query and executes it
public static void main(String[] args) {
Map map = Query(args);
// Make sure a query was given.
if(map == null) {
System.out.println("Wrong arguments");
System.exit(1);
else {
new Tw().search(map);
private void search(Map map) {
Geocoder geol = Getuserlocation(map.town);
if(geol == null) {
System.out.println("Town " + map.town + " coordinates are not found");
System.exit(1);
List<Twpost> posts = Findmessage(geol);
if(posts.size() > 0) {
if(map.sort != null) {
TwpostComparator comparator = new TwpostComparator(map.sort);
Collections.sort(posts, comparator);
printPosts(posts);
else {
System.out.println("No entries for town " + map.town + " found");
private void printPosts(List<Twpost> posts) {
SimpleDateFormat formatter = new SimpleDateFormat(OUTPUT_DATE_PATTERN);
for(Twpost post : posts) {
System.out.println(formatter.format(post.date) + " "
+ post.content);
private List<Twpost> Findmessage(Geocoder geol) {
NumberFormat format = DecimalFormat.getNumberInstance(Locale.US);
String url = MessageFormat.format(TWITTER_URL, format.format(geol.x),
format.format(geol.y), TWITTER_SEARCH_RADIUS);
List<Twpost> posts = null;
try {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(url);
doc.getDocumentElement().normalize();
NodeList dates = doc.getElementsByTagName("post");
for (int s = 0; s < dates.getLength(); s++) {
Twpost post = new Twpost();
String dateStr = (String)dates.item(s).getTextContent();
post.date = pdate(dateStr);
Element publish = (Element) dates.item( s );
System.out.println( publish.getFirstChild().getNodeValue() );
post.content=((Element)dates.item(s)).getElementsByTagName("content").
item(0).getFirstChild().getNodeValue();
post.author=((Element)dates.item(s)).getElementsByTagName("name").
item(0).getFirstChild().getNodeValue();
posts.add(post);
catch (Exception e) {
return posts;
private NodeList getElementsByTagName(Document doc, String xpathExpr) {
NodeList result = null;
try {
XPathFactory factory = XPathFactory.newInstance();
XPath xpath = factory.newXPath();
XPathExpression expr = xpath.compile(xpathExpr);
result = (NodeList)expr.evaluate(doc, XPathConstants.NODESET);
}catch (Exception e) {
return result;
private Date pdate(String dateStr) {
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'");
Date d = null;
try {
d = formatter.parse(dateStr);
formatter.setTimeZone(TimeZone.getTimeZone("UTC"));
catch (Exception e) {
return d;
private Geocoder Getuserlocation(String town) {
String url = MessageFormat.format(GOOGLE_MAPS_URL, town);
Geocoder geol = null;
try {
InputStream instream = new URL(url).openStream();
BufferedReader reader = new BufferedReader(
new InputStreamReader(instream));
String[] s = reader.readLine().split(",");
geol = new Geocoder();
geol.x = Double.parseDouble(s[2]);
geol.y = Double.parseDouble(s[3]);
} catch (Exception e) {
return geol;
private static Map Query(String[] args) {
Map map = null;
if(args.length > 0 && args.length <= 2) {
map = new Map();
if(args.length == 1) {
map.town = args[0];
if(args.length == 2) {
map.sort = args[1];
return map;
who wants to add something and make it better?