Spring MVC implementation File download

Download File ①

The download file requires a byte array to be restored as a file.

First, use MyBatis to isolate the byte array in the database, specifying the file name (including the format). Then use OutputStream to enter the file

2. @RequestMapping (value = "Downphotobyid")
4. public void Downphotobystudentid (String ID, Final httpservletresponse response) {
6. photoentity entity = this.photoMapper.getPhotoEntityByPhotoId (ID);
8. byte[] data = Entity.getphotodata ();
10. String fileName = entity.getfilename () = = null? "Photo. png": Entity.getfilename ();
12. filename = urlencoder.encode (filename, "UTF-8");
14. Response.reset ();
16. Response.setheader ("Content-disposition", "attachment; Filename=\ "" + fileName + "\" ");
18. Response.AddHeader ("Content-length", "" "+ data.length);
20. Response.setcontenttype ("Application/octet-stream;charset=utf-8");
22. OutputStream outputstream = new Bufferedoutputstream (Response.getoutputstream ());
24. Outputstream.write (data);
26. Outputstream.flush ();
28. Outputstream.close ();
30. }

1. <a href= "<%=request.getcontextpath ()%>/downphotobyid.do?id=8000001" > Download photos </a>

Download File ②

/** * @Description Download file

* @author JXLDJSN

* @date December 11, 2015 6:11:33

* @param fileName

* @param file

* @return

* @throws IOException

*/

Public responseentity<byte[]> Download (String fileName, File file) throws IOException {

String dfilename = new String (Filename.getbytes ("gb2312"), "iso8859-1");

Httpheaders headers = new Httpheaders (); Headers.setcontenttype (Mediatype.application_octet_stream); Headers.setcontentdispositionformdata ("Attachment", dfilename);

return new responseentity<byte[]> (Fileutils.readfiletobytearray (file), headers, httpstatus.created); }

Download File ③

Main methods of File download  PublicStaticvoid Download (HttpServletRequest request,  HttpServletResponse response, String storeName, String ContentType )Throws Exception {   Request.setcharacterencoding ("UTF-8"); Bufferedinputstream bis =Null Bufferedoutputstream BOS =Null  Get the project root directory String Ctxpath = Request.getsession (). Getservletcontext ()   . Getrealpath ("");    Get download File shoulder String Downloadpath = ctxpath+"/uploadfile/" + storeName;  Get the length of a file  Long filelength =New File (Downloadpath). Length ();  Set file Output Type Response.setcontenttype ("Application/octet-stream"); Response.setheader ("Content-disposition","Attachment; Filename= "   +New String (Storename.getbytes ("Utf-8"),"Iso8859-1"));  Setting the output length Response.setheader ("Content-length", String.valueof (Filelength));  Get input stream bis =New Bufferedinputstream (New FileInputStream (Downloadpath));  Output stream BOS =New Bufferedoutputstream (Response.getoutputstream ());  byte[] buff = new byte[2048];   int bytesread; While   (-1! = (Bytesread = bis.read (buff, 0, Buff.length))) {   bos.write (Buff, 
                                                                                                       
                                                                                                        0, Bytesread); 
                                                                                                         }   //Close stream  bis.close ();  bos.close ();  }  }
                                                                                                       < /c10> 


Download direct access controller such as: http:\\localhost:8080/springmvc/download.do

Download File ④

2. @RequestMapping ("/export")
4. Public responseentity<byte[]> Export () throws IOException {
6. Httpheaders headers = new Httpheaders ();
8. Headers.setcontenttype (Mediatype.application_octet_stream);
10. Headers.setcontentdispositionformdata ("attachment", "Dict.txt");
12. return new responseentity<byte[]> (Fileutils.readfiletobytearray ("New File" ("c:/users/ Administrator/desktop/a.txt ")),
14. headers, httpstatus.created);
16. }

Spring MVC implementation File download