android客户端与服务端交互的工具类

public class HttpUtil {

    //创建HttpClient对象
    public static HttpClient httpClient = new DefaultHttpClient();
    public static final String BASE_URL="http://xxx.xxxx.xx.xx:8080/ticket/";
//  public static final String BASE_URL="http://xxx.xxxx.xx.xx:8080/apk/";
//  public static final String BASE_URL = "www.baidu.com";
    /**
     * 
     * @param url 发送请求的Url
     * @return 服务器响应的字符串
     * @throws Exception 
     * @throws InterruptedException 
     */
    public static String getRequest(final String url) throws Exception {
        FutureTask<String> task = new FutureTask<String>(
            new Callable<String>() {

                @Override
                public String call() throws Exception {
                    //创建HttpGet对象
                    HttpGet get = new HttpGet(url);
                    //发送GET请求
                    HttpResponse response = httpClient.execute(get);
                    //若是服务器响应成功
                    if(response.getStatusLine().
                            getStatusCode() == 200) {
                        //获取服务器响应的字符串
                        String result = EntityUtils.
                                toString(response.getEntity());
                        return result;
                    }
                    return null;
                }
            }
        );
        new Thread(task).start();
        return task.get();
    }

    /**
     * 
     * @param url 发送请求的url
     * @param rawParams 请求参数
     * @return 响应的字符串
     * @throws Exception
     */
    public static String postRequest(final String url,
            final Map<String,String> rawParams) throws Exception {
//      ExecutorService exec=Executors.newCachedThreadPool(); 
//      FutureTask<String> task = new FutureTask<String>(
//          new Callable<String>() {

//              @Override
//              public String call() throws Exception {
                    //创建HttpPost对象
                    HttpPost post = new HttpPost(new URI(url));
                    //对较多的传递参数进行封装、
                    List<NameValuePair> params = new ArrayList<NameValuePair>();
                    for(String key : rawParams.keySet()) {
                        //封装请求参数
                        params.add(new BasicNameValuePair(key, rawParams.get(key)));
                    }
                    //设置请求参数
                    post.setEntity(new UrlEncodedFormEntity(params,HTTP.UTF_8));
                    //发送post请求
                    HttpResponse response = httpClient.execute(post);
                    //若是服务器响应成功
                    if(response.getStatusLine().getStatusCode() == HttpStatus.SC_OK){
                        //获取服务器响应的字符串  
                        String result = EntityUtils.toString(response.getEntity(),HTTP.UTF_8);
                        return result;
                    }else{
                        return "-1";
                    }

                }
//          }
//      );
//      new Thread(task).start();
//      return task.get();
//  }


}

public void service(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        String uri = request.getRequestURI();
        uri = uri.substring(uri.lastIndexOf("/"));
        System.out.println("uri: " + uri);
        if("/hotStation.do".equals(uri)) {
            doHotStationList(request, response);
        }
        if("/stationList.do".equals(uri)) {
            doStationList(request, response);
        }
    }

public void doHotStationList(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=UTF-8");
        List<String> hotStationList = StationService.getHostStationList();
        JSONArray jsonArray = JSONArray.fromObject(hotStationList);
        System.out.println("传给客户端:" + jsonArray.toString());
        response.getWriter().println(jsonArray.toString());
    }