根据用户坐标返回用户地理位置，并且统计用户

package com.baidu.map;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.Reader;

import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpException;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.params.HttpClientParams;
import org.json.JSONException;
import org.json.JSONObject;

public class MapTest
{
  private static String MAP_API = "http://api.map.baidu.com/geocoder/v2/?ak=HFK1yUSyGFZyj0fuA5cyrn3z&callback=renderReverse&output=json&pois=1&location=";

  public static void main(String[] args) throws HttpException, IOException, JSONException
  {
    System.out.println(new File(".").getAbsolutePath());
    // map.data.txt 文件内是用户的坐标，  纬度,经度
    File file = new File("./src/map.data.txt");
    Reader reader = new FileReader(file);
    BufferedReader breader = new BufferedReader(reader);
    String line = breader.readLine();
    int count = 0;
    while (line != null && line.length() > 0)
    {
      String[] sts = line.split(",");
      String latitude = sts[0];
      String longitude = sts[1];
      String city = getCity(latitude.trim(), longitude.trim());
      if (city.contains("北京"))
      {
        count++;
      }
      line = breader.readLine();
    }
    System.out.println(count);
  }

  public static String getCity(String latitude, String longitude) throws HttpException, IOException, JSONException
  {
    HttpClient hc = new HttpClient();
    String api = MAP_API + latitude + "," + longitude;
    GetMethod httpget = new GetMethod(api);
    HttpClientParams ps = hc.getParams();
    ps.setContentCharset("UTF-8");
    hc.executeMethod(httpget);
    System.out.println(api);
    String response = httpget.getResponseBodyAsString();
    response = response.replace("renderReverse&&renderReverse(", "");
    response = response.substring(0, response.length() - 1);
    JSONObject obj = new JSONObject(response);
    System.out.println(obj.getJSONObject("result").getString("formatted_address"));
    return response;
  }
}