Servlet File Download class sharing

Last Update:2014-01-18 Source: Internet

Author: User

Tags log log

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Copy codeThe Code is as follows:
Package com;

Import java. io. IOException;
Import java. io. PrintWriter;
Import java.net. URLEncoder;
Import java. util. Date;

Import javax. servlet. ServletException;
Import javax. servlet. http. HttpServlet;
Import javax. servlet. http. HttpServletRequest;
Import javax. servlet. http. HttpServletResponse;

Import org. apache. commons. logging. Log;
Import org. apache. commons. logging. LogFactory;

Import com. sun. xml. internal. messaging. saaj. packaging. mime. internet. MimeUtility;

/**
* File Download class. To prevent the client browser from directly opening the target file (for example, in Windows with MS Office suite installed, ie may directly open the doc or xls file you want to download in IE ), add the forced download MIME type to the response header.
*/
Public class DownloadFile extends HttpServlet {
Private static final Log log = LogFactory. getLog (DownloadFile. class );

Public void doGet (HttpServletRequest request, HttpServletResponse response) throws ServletException {
Long timeStart = 0;
If (log. isDebugEnabled ()){
TimeStart = System. currentTimeMillis ();
}
Response. setContentType ("application/x-download charset = UTF-8 ");
Java. io. FileInputStream FCM = null;
String filepath = request. getRealPath ("");
Javax. servlet. ServletOutputStream sos = null;
// System. out. println ("DownloadFile filename:" + filename );
Try {
If (request. getParameter ("filename") = null
| Request. getParameter ("showName") = null ){
Return;
}
String filename = request. getParameter ("filename ");
String showName = request. getParameter ("showName ");
Request. setCharacterEncoding ("UTF-8 ");
Response. setCharacterEncoding ("UTF-8 ");
Java. io. File file = new java. io. File (filepath + filename );
If (! File. exists ()){
Log. error (file. getAbsolutePath () + "the file does not exist! ");
Return;
}
// Read the file stream
FS = new java. io. FileInputStream (file );
// Set the file name to download and save
Sos = response. getOutputStream ();
ShowName + = filename. substring (filename. lastIndexOf ("."));
String contentDisposition = "", browser = getBrowser (request );
If ("IE". equals (browser )){
ContentDisposition = "attachment; filename =" + URLEncoder. encode (showName, "UTF-8"). replace ("+", "% 20 ");
} Else if ("CH". equals (browser )){
ContentDisposition = "attachment; filename =" + MimeUtility. encodeText (showName, "UTF8", "B ");
} Else if ("SF". equals (browser )){
ContentDisposition = "attachment; filename =" + new String (showName. getBytes ("UTF-8"), "ISO8859-1 ");
} Else {
ContentDisposition = "attachment; filename * = UTF-8'' "+ URLEncoder. encode (showName," UTF-8 "). replace (" + "," % 20 ");
}
Response. setHeader ("Content-Disposition", contentDisposition );
Int byteCount = 0;
If (FS! = Null ){
Byte [] buff = new byte [1024];
Int bytesRead;
While (-1! = (BytesRead = Fi. read (buff, 0, buff. length ))){
Sos. write (buff, 0, bytesRead );
Sos. flush ();
ByteCount + = bytesRead;
}
}
Sos. flush ();
If (log. isDebugEnabled ()){
Log. debug ("file download completed, file size:" + byteCount + ", total time:" + (new Date (). getTime ()-timeStart) + "millisecond. ");
}
} Catch (IOException ioe ){
Ioe. printStackTrace ();
} Finally {
Try {
If (FS! = Null ){
FCM. close ();
}
} Catch (IOException e ){
} Finally {
Try {
If (sos! = Null ){
Sos. close ();
}
} Catch (IOException e ){
}
}
}
}

Public void doPost (HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
Response. setContentType ("text/html ");
PrintWriter out = response. getWriter ();
Out. println ("<! DOCTYPE html PUBLIC \ "-// W3C // dtd xhtml 1.0 Transitional // EN \" \ "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\"> ");
Out. println ("Out. println ("Out. println ("<title> File Download </title> ");
Out. println ("<meta http-equiv = \" Content-Type \ "content = \" text/html; charset = UTF-8 \ "/> ");
Out. println ("Out. println ("<body> ");
Out. print ("This is ");
Out. print (this. getClass (). getName ());
Out. println (", using the POST method ");
Out. println ("</body> ");
Out. println ("Out. flush ();
Out. close ();
}

Private String getBrowser (HttpServletRequest request ){
String userAgent = request. getHeader ("USER-AGENT"). toLowerCase ();
If (userAgent! = Null ){
If (userAgent. indexOf ("msie")> = 0 ){
Return "IE ";
} Else if (userAgent. indexOf ("mozilla")> = 0 ){
Return "FF ";
} Else if (userAgent. indexOf ("applewebkit")> = 0 ){
Return "CH ";
} Else if (userAgent. indexOf ("safari")> = 0 ){
Return "SF ";
} Else if (userAgent. indexOf ("opera")> = 0 ){
Return "OP ";
}
}
Return null;
}
}

This article is an English version of an article which is originally in the Chinese language on aliyun.com and is provided for information purposes only. This website makes no representation or warranty of any kind, either expressed or implied, as to the accuracy, completeness ownership or reliability of the article or any translations thereof. If you have any concerns or complaints relating to the article, please send an email, providing a detailed description of the concern or complaint, to info-contact@alibabacloud.com. A staff member will contact you within 5 working days. Once verified, infringing content will be removed immediately.

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