簡單的檔案下載後讀取顯示，該方法可返回內容的結果集。一般適用於文字文件的下載，以供學習交流。

/**
    * 遠端下載檔案並讀取返回p
    * @param filePath 檔案網路地址 如http://www.baidu.com/1.txt
    * @return String
    */
   public String DownAndReadFile(String filePath){
	   String date = new SimpleDateFormat("yyyy-MM-dd").format(new Date());	   
	   File savePath = new File("D://"+date);//建立新檔案
	   if (!savePath.exists()) { 
		   savePath.mkdir(); 
       }
	   String[] urlname = filePath.split("/");
	   int len = urlname.length-1;
	   String uname = urlname[len];//獲取檔名
	   try {
		   File file = new File(savePath+"//"+uname);//建立新檔案
		   if(file!=null && !file.exists()){
			   file.createNewFile();
		   }
		   OutputStream oputstream = new FileOutputStream(file);
		   URL url = new URL(filePath);
		   HttpURLConnection uc = (HttpURLConnection) url.openConnection();
		   uc.setDoInput(true);//設定是否要從 URL 連線讀取資料,預設為true
		   uc.connect();
		   InputStream iputstream = uc.getInputStream();
		   System.out.println("file size is:"+uc.getContentLength());//列印檔案長度
		   byte[] buffer = new byte[4*1024];
		   int byteRead = -1;	
		   while((byteRead=(iputstream.read(buffer)))!= -1){
			   oputstream.write(buffer, 0, byteRead);
		   }
		   oputstream.flush();	
		   iputstream.close();
		   oputstream.close();
		   //讀取檔案
		   StringBuffer strb = new StringBuffer();
		   FileInputStream fs = new FileInputStream(new File(savePath+"//"+uname));
		   InputStreamReader isr = new InputStreamReader(fs,"UTF-8");
		   BufferedReader br = new BufferedReader(isr);
		   String data = "";
		   while((data = br.readLine()) != null){
			   strb.append(data + "\n");
		   }
		   br.close();
		   fs.close();
		   isr.close();
		   System.out.println(strb.toString());
		   return strb.toString();
		   
	} catch (Exception e) {
		System.out.println("讀取失敗！");
		e.printStackTrace();
	}   
	   return null;
   }