Android 获取下载文件的真实名字

    public static String getReallyFileName(String url) {  
            String filename = "";  
            URL myURL;  
            HttpURLConnection conn = null;  
            if (url == null || url.length() < 1) {  
                return null;  
            }  
      
            try {  
                myURL = new URL(url);  
                conn = (HttpURLConnection) myURL.openConnection();  
                conn.connect();  
                conn.getResponseCode();  
                URL absUrl = conn.getURL();// 获得真实Url  
                Log.e("H3c","x:" + absUrl);  
                // 打印输出服务器Header信息  
                // Map<String,List<String>> map = conn.getHeaderFields();  
                // for (String str : map.keySet()) {  
                // if (str != null) {  
                // Log.e("H3c",str + map.get(str));  
                // }  
                // }  
                filename = conn.getHeaderField("Content-Disposition");// 通过Content-Disposition获取文件名，这点跟服务器有关，需要灵活变通  
                if (filename == null || filename.length() < 1) {  
                    filename = absUrl.getFile();  
                }  
            } catch (MalformedURLException e) {  
                e.printStackTrace();  
            } catch (IOException e) {  
                e.printStackTrace();  
            } finally {  
                if (conn != null) {  
                    conn.disconnect();  
                    conn = null;  
                }  
            }  
      
            return filename;  
        }