將數據從服務器傳輸到servlet

Question

我需要使用servlet將數據從外部服務器傳輸到我的主機。而不是上傳文件，我需要從另一臺服務器下載。 我試過正常下載Java程序，但它不能正常工作

Answer 1

in servlet你可以從一個特定的URL獲取文件並將其發送到客戶端這樣的：

public void doGet(HttpServletRequest req, HttpServletResponse res) 
     throws ServletException, IOException, UnavailableException 
    { 

     int bytesRead = 0; 
     int count = 0; 
     byte[] buff = new byte[1]; 

     OutputStream out = res.getOutputStream(); 

     res.setContentType("application/contenttype");//i.e: contenttype=pdf,doc,etc"); 

     String fileURL = "http://someaddress/somefile.someextension"; 
     BufferedInputStream bis = null; 
     BufferedOutputStream bos = null; 

     res.setHeader("Content-disposition", 
         "attachment; filename=somefile.someextension;"); 

     URL url = new URL(fileURL); 
     bis = new BufferedInputStream(url.openStream()); 
     bos = new BufferedOutputStream(out); 
     while (-1 != (bytesRead = bis.read(buff, 0, buff.length))) 
      { 
       bos.write(bytesRead); 
       bos.flush(); 

      } 
    } 

注意：您需要辦理有關也有例外。