- What
do I need to run JFileUpload ?
You need Java (JRE 1.4 or higher) installed on client-side.
- How
to setup JFileUpload Applet ?
JFileUpload applet includes two sample files: One for HTTP upload (see applet_http.html and applet_http.js) and one for FTP upload (see applet_ftp.html and applet_ftp.js). Edit and modify parameters
in the JavaScript file (the one ending by .js) matching to your need.
- Why
all parameters must be setup twice ?
You need to setup all parameters twice for cross-browser
support. For instance, for "url" parameter
you have to setup:
...
url = "http://yourserver.com/upload.jsp"
...
<PARAM name="url" value="http://yourserver.com/upload.jsp">
...
JFileUpload applet works under Internet Explorer, Safari, Firefox, Netscape, Opera and Google chrome. See software section.
It is recommended to copy/paste existing parameter when you want to add a new one. It will avoid typo mistake in the JavaScript.
- I
get "Connection refused" error message ?
It means that "url" parameter of JFileUpload
is not setup. For HTTP upload, it must be the URL
of the server-side script that will handle the upload
(i.e. parse multipart request), for instance http://mycompany.com/upload.php.
This error could also mean that your FTP (or HTTP)
server is not up.
- I
get "server error 404" error message ?
Same as question above. Your "url" parameter
is wrong.
- Applet
fails to load, I get ClassFormatError: Incompatible
magic value ?
Double check that installed JAR files are not
corrupted. If you've transfered them on a web server
through FTP then make sure that transfer has been
done in BINARY mode.
- Why
do I need a server-side script too ?
JFileUpload is just a client-side component
that could upload files or folders to a server. You
need a server-side script - for HTTP only - to store
uploaded files. For FTP, you just need a FTP server.
- For
HTTP, can I use PHP, ASP, ColdFusion or PERL as server-side
script ?
Yes, JFileUpload uploads files through standard
HTTP multipart request. Your server-side script could
be written in PHP, JSP, ASP, ASP.NET, CGI/Perl, CGI/C++,
Ruby, ColdFusion ...
- Why
do you recommend JSPUpload as server-side script
?
We recommend JSPUpload with process.jsp script because it includes advanced
features (very large upload with low memory, folders
structure recomposition, resume and overwrite support, checksum
...) you might have to develop in your own script.
However, JSPUpload needs Servlet/JSP support on server-side.
Notice that you will find others upload script samples
(such as PHP and ASP.NET) in add-ons section.
- How
to re-create folders structure on server-side when
uploading a folder with multiples files and subfolders
?
First, you have to select the recursive depth through
"folderdepth" parameter of JFileUpload.
Second, you need to enable "relativefilename"
extra parameter on JFileUpload through paramX=relativefilename
and valueX=true (with X in [1-16]). For instance:
folderdepth="5"
param1="relativefilename"
value1="true"
Finally - for HTTP only - you need a server-side script
that will handle "relativefilename" parameter
to create folders and subfolders before storing uploaded
files.
(process.jsp server-side
script included in JSPUpload provides this feature).
- How
to select an initial directory on FTP server before
uploading files through FTP ?
Use "account" extra parameter through paramX=account
and valueX=dirname (with X in [1-16]). For instance:
param1="account"
value1="mydirectory/mysubdirectory"
- How
to create an initial directory on FTP server before
uploading files ?
Set "account" parameter above and set "accountcreation"
extra parameter to "true". For instance:
param2="accountcreation"
value2="true"
- My FTP connection is not reliable and some upload fails, what can I do ?
Enable "retry" parameter to ask JFileUpload to make several attempts - when current upload fails - before reporting and error. For instance, to enable three attempts:
retry="3"
You can also setup "retrydelay" parameter to add a a few seconds delay between each attempts:
retrydelay="5"
- How
to redirect to an URL after upload completed ?
Use "forward" parameter such as forward=http://company.com/another.html
If you need to redirect to a given frame of window
then use "forwardtarget".
If you need to append uploaded filenames to redirect
URL then set "forwardparameters" to true.
- Is
it possible pass a HTTP POST request after upload
completed ?
Yes, see "post" and "postparameters".
It allows JFileUpload to send a HTTP POST request
with uploaded filenames (and path). It could be useful
if you need to send an email, store a status in database,
... after upload. For instance, post=http://company.com/postscript.php
- What
happen to the response of the HTTP POST ?
Reponse of "post" url is discarded by JFileUpload.
- Could
both "post" and "forward" parameters
work together ?
Yes, "forward" will be processed after
"post". It means that HTTP POST request
will be sent prior to HTTP GET matching to URL redirection.
To be more precise :
1 - JFileUpload: Send HTTP POST ---->
Server : Process POST request.
2 - JFileUpload: Discard response <----
Server : Send response.
3 - JFileUpload: Send HTTP GET ---->
Server : Process GET request.
4 - Browser: Display HTML response <----
Server : Send response.
- Can
I pass additional parameter to "forward"
parameter ?
Yes, try forward="http://company.com/another.html?custom=something"
- How
"forwardparameters" work if I upload many
files ?
Depending on browser, URL size is limited (from 256
to 4000 characters) so the generated URL might be
too long (http://company.com/another.html?filename1=...)
if you upload more than 100 files. The solution is
to use "post" and "postparameters"
to get all filenames (because there is no limitation
in POST size) and use "forward" parameter
only to redirect.
- How
to modify JFileUpload resources (messages, menu,
errors ...) ?
Most JFileUpload resources could be modified. A
resource could be an info message, an error message,
a menu item or a color. First, copy and modify i18n.properties in the same directory as JFileUpload applet. Second,
setup "resources" parameter such as:
resources = "i18n"
Pay attention to setup it to i18n and not i18n.properties.
Finally, edit and modify i18n.properties as you need.
This file is an ASCII file and # means comment.
If you need extra characters such as german (Ä, Ö,
ü, ...) or chinese, japanese, korean ... then convert
them into unicode format through JRE native2ascii
tool.
- How
to internationalize JFileUpload resources (messages,
errors , ...) ?
JFileUpload is ready for internationalization. First,
enable "resources" parameter as explained
above. i18n.properties will be the default resources
file. Second, if you want JFileUpload to support
multiple languages then add i18n_xy.properties translated
files (with xy the ISO
639 language code such as : en, es, de, zh ...).
For instance, to add german support :
1 - Copy i18n.properties into
i18n_de.properties.
2 - Translate all resources
in german in i18n_de.properties.
3 - Optionally, use JRE/bin/native2ascii.exe
tool to convert extra characters.
JFileUpload will automatically load i18n_de.properties
if end-user settings are in german (and if localeresources parameter is setup to true). If not then it
will load i18n.properties.
- How
display file browser window on "File" item
instead of "Select file(s)" ?
Comment menu.file.open key in your custom i18n.properties
such as:
menu.file.open=Select file(s)
#menu.file.open=Select file(s)
- How
to remove the top menu bar and add a "Select
file(s)" button ?
To enable a "Select file(s)" button  on the left of "Cancel" button, uncomment
progress.button.select key in your custom i18n.properties
such as:
#progress.button.select=Select
file(s)
progress.button.select=Select
file(s)
Then to hide the menu bar, set "hidebar"
parameter to true:
hidebar = "true"
...
<PARAM name="hidebar" value="true">
- Can
JFileUpload display "time elapsed" when
uploading file ?
Yes, enable both progress.info and progress.info.label
keys in i18n.properties. Time remaining and transfer speed is available too. It could also display an
overall progress bar (in addition to file upload progress bar).
- How
to add a background image to the upload info/drag&drop
panel ?
Uncomment "taskoutput.image.background"
property in your i18n.properties and setup your image
filename .
- Is
it possible to have an image previewer in file chooser
?
Yes, to enable this feature uncomment the following
keys in your i18n.properties:
filechooser.preview.image=enabled
filechooser.preview.image.title=Image
preview
filechooser.preview.image.enabled=Enabled
- How
to modify JFileUpload fonts ?
There are "font.face" and "font.size"
keys/values in i18n.properties. It allows to load
true type fonts and apply them over all JFileUpload
resources (label, button, menu ...). This feature
could be useful for accessibility.
- How
to have a Microsoft Windows-like JFileUpload front-end
?
Enable lookandfeel=com.sun.java.swing.plaf.windows.WindowsLookAndFeel
key in i18n.properties .
You can also setup lookandfeel=auto to fit to the
underlying operating system look and feel.
- Applet
is not loading (grey box) when hosted under IIS ,
what should I do ?
Basically, IIS settings don't allow to serve files
with unknown extensions. IIS returns 404 error when
JFileUpload tries to load i18n.properties.
You have to update IIS settings to map ".properties"
to "text/plain" mime-type. See instructions
for IIS 4.x/5.x or 6.x.
- I
get "Can't find bundle for base name i18n"
error, what should I do ?
See question above, even if you have a Unix/Linux
or MacOSX server. It will work when you could access
i18n.properties directly from your browser through
http://yourserver.com/something/i18n.properties.
- How
to pass a cookie from JFileUpload to server-side
?
Use both
"cookiename" and "cookievalue"
extra parameters through paramX,valueX (with X in
[1-16]). For instance:
param5="cookiename"
value5="mycookie"
param6="cookievalue"
value6="myvalue12345"
- How
to maintain user's HTTP session with server-side ?
Most HTTP sessions are maintained through a cookie.
See question above to learn how to pass a cookie (for
JSP, cookiename should be JSESSIONID). You could also
pass session as URL rewriting, then modify "url"
parameter to pass it (for JSP url=...upload.jsp;jsessionid=xyz12345).
You could also use URL rewriting for "forward"
and "post" parameters.
- How
to pass custom error from upload script to JFileUpload
front-end ?
Enable "errorheader" extra parameter such
as:
param7="errorheader"
value7="custommessage"
Then, pass "custommessage"="whatyouwanttobedisplayed"
header in HTTP 405 response sent by your upload script.
JFileUpload will try to read the header to display
the error message in front-end.
- Does
JFileUpload support HTTPS ?
Yes, it does. url parameter must start with "https://...".
Just pay attention to have trusted X509 certificate
on JRE client.
- Does
JFileUpload support FTPS and SFTP ?
Yes, it does. FTPS is supported natively. url parameter must start with "ftps://...".
Just pay attention to have trusted X509 certificate
on JRE client. SFTP support requires SFTP add-on, url parameter must start with "sftp://...".
- I
get "No trusted certificate ..." error with
HTTPS and FTPS ?
It means that you're not using a trusted X509 certificate
for SSL. The signer of the certificate is not in the
JRE CA list (cacerts file) so you cannot open any
SSL connection with Java. You have 3 solutions:
1 - Deploy the certificate
in JRE of all JFileUpload users.
(Not
easy in production).
2 - Use WeakSSL plugin
in JFileUpload add-ons section.
(It
allows to bypass trusted CA checking. Useful for testing
purpose).
3 - Purchase a trusted
certificate for SSL from company such as VeriSign or Thawte.
(Recommended in production).
- I get "Access denied" when uploading with "chunksize" under Windows Vista ?
Internet Explorer
7 under Windows Vista comes with new security features. A standard windows user account doesn't have permissions to write in some directories such as c:\, c:\Program Files ... "chunksize" parameter allows to split file in chunks before uploading. Basically, each chunks is written temporary on disk in the same folder as the selected file to upload. If you select file in a folder where you don't have write permissions then chunks cannot be created and you get "Access denied" errors. You will have the same problem with "ziponfly" parameter and plugins such as Scaling Filter. The solution is to setup JFileUpload to generate any temporary files under user's home tmp folder through:
...
<PARAM NAME="tmpfolder" VALUE="javatmpdir">
...
Another solution, that applies to "chunksize" parameter only, is to setup JFileUpload to generate each chunks in memory through:
...
<PARAM NAME="chunkmode" VALUE="onfly">
...
- How
to hide FTP username and password in HTML code ?
JFileUpload supports base-64 encoded parameters.
Enclose value in [] to pass base-64 encoded string.
For instance to encode password parameter:
param2="password"
value2="qwerty1234"
then use any base-64
encoder/decoder service to get :
param2="password"
value2="[cXdlcnR5MTIzNA==]"
Note that base-64 encoding is not encryption. Since 2.3 encryption is available for username and password, we can encrypt your credentials upon request to our support team.
- Is
it possible to NOT store url and username/password
in HTML ?
Yes, if you don't want url and username/password parameters
in HTML, even base-64 encoded, then you could append
them in i18n.properties file such
as:
url=ftp://yourftpserver.com
username=yourftplogin
password=yourftppassword
- Is
it possible to pass FTP username/password through
JavaScript ?
Yes, try the following in your JavaScript :
document.fileupload.setParameter("username","yourlogin")
document.fileupload.setParameter("password","yourpassword")
See others section to learn
more about JavaScript API.
- Could
JFileUpload work with a proxy ?
Yes, JFileUpload will attempt to auto-detect HTTP
or SOCKS proxy. However, you could force proxy settings
if needed.
- Does
JFileUpload support HTTP WWW-Authenticate ?
Yes, JFileUpload supports basic WWW-Authenticate
through username and password parameters.
- Does
JFileUpload support explicit SSL mode (AUTH TLS)
for FTPS ?
Yes, default FTPS setup is AUTH TLS with protection
channel enabled (PROT P). JFileUpload also supports
AUTH SSL and SSL Connect (implicit mode). You could
switch between these modes through "ftpsmode"
parameter. You could disable protection channel through
"ftpsprot" parameter.
| Large upload and compression |
- Can
JFileUpload compress file automatically before upload
?
Yes, JFileUpload could zip file before upload if
you enable "ziponfly" parameter. Here is
how JFileUpload works:
1 - Create a temporary ZIP
file (such as originalfilename.zip).
2 - Upload the compressed
file.
3 - Delete the temporary ZIP
file.
Notice that file stored on
server-side will be originalfilename.zip
Using this parameter could lower bandwidth usage but
it will affect client-side performance because of
compression process. Don't enable "ziponfly"
parameter if you plan to transfer compressed files
such as GIF, JPEG, MP3, ... JFileUpload allows skipping such files with "zipignorelist" parameter.
JFileUpload could also zip all files in one overall archive before upload. See the compression tutorial to learn how to setup this feature.
- How
to upload files > 2GB through HTTP ?
First, you have to set "chunksize" parameter
on JFileUpload. Chunksize must be under 2GB (for
256MB, chunksize=268435456). Here is how JFileUpload
works:
1 - Split file to upload in
temporary chunks (such as originalfilename.chunkid).
2 - Upload each chunk.
(with
additionnal chunkid, chunkamount, chunkbase HTTP parameters).
3 - Delete each temporary
chunk file.
Second, you need a server-side script that handles
chunkid, chunkamount, chunkbase HTTP parameters to
re-compose file from uploaded chunks.
(process.jsp server-side
script included in JSPUpload provides this feature).
- Resume doesn't work with my Microsoft FTP server ?
Try to set resumecommand extra parameter such as:
param3="resumecommand"
value3="append"
- How JFileUpload could resume broken uploads ?
Uncomplete upload could occur on system/network failure
or simply because you've cancelled upload. JFileUpload
can resume uncomplete uploads. Use "resume" parameter to enable this feature. JFileUpload sends
an additional request to server to know if current
upload should be resumed. If you're interested in
knowing how it works then see details below:
For FTP:
1 - Applet sends LIST command with current filename
to upload.
2 - FTP server returns remote file info (size,
date) if available.
3 - If remote file size < local file size
then Applet sends REST resumeindex command.
4 - Applet sends STOR command to upload file
(starting at resumeindex).
For HTTP:
Resuming is more complex and requires a server-side
script that supports
"Content-Range" header :
1 - Applet sends HEAD request with "filename" header for current upload.
2 - Server script must return "HTTP 404
not found" response if file does not
exist or "HTTP
200 OK" response with file size in a "size" header if file exists.
3 - If remote file size < local file size
then Applet sends HTTP multipart POST
request with "Content-Range" header including resumeindex.
4 - Server script handles upload request and
append data to remote file.
(process.jsp
server-side script included in JSPUpload provides
this feature).
- How
JFileUpload could rename duplicated files before
upload ?
JFileUpload can check if file already exists on
server before uploading it. Use overwrite parameter
to enable this feature. JFileUpload sends an additional
request to server to know if current upload should
be overwritten or not. If you're interested in knowing
how it works then see details below for HTTP :
1 - Applet sends HEAD request with "filename"
header for current upload.
2 - Server script must return "HTTP 404
not found" response if file does not
exist or "HTTP
200 OK" response with file size in a "size"
header if file exists.
3 - Applet applies overwrite policy (indexrename,
...) and loops to step 1 until
making sure that
the file to upload doesn't exist on server.
4 - Applet sends HTTP multipart POST request
to upload file with the new name.
5 - Server script handles upload request and
save file.
(process.jsp server-side
script included in JSPUpload provides this feature).
Note: You could use the "template"
parameter to rename files to upload. It would avoid
the additional request.
- Could
resume and overwrite features work together ?
Yes, if both are enabled then resume is prior to overwrite.
Resume and overwrite will also work with folders and
subfolders upload.
- How to have dynamic parameters in applet_http.js JavaScript file ?
Do the same as you did for any dynamic file. For instance, for PHP rename the file as applet_http_js.php, add your PHP code and modify link in applet_http.html such as <script src="applet_http_js.php"></script>
- How
to pass extra parameters to JFileUpload from JavaScript
?
JFileUpload supports JavaScript to Applet communication.
Use document.fileupload.setParameter(name,value)
to pass or update extra parameters. For instance in your HTML:
[...]
<SCRIPT LANGUAGE="JavaScript"><!--
function modify(val)
{
document.fileupload.setParameter("anotherHTTPparam",val);
}
//--></SCRIPT>
[...]
<form name="myform" method="post"
action="">
<input name="custom" type="text">
<input type="button" name="mybutton"
value="test" onClick="modify(myform.custom.value)">
[...] |
- How
to update regular applet parameters from JavaScript ?
There is a document.fileupload.setProperty(name,value)
method allowing to update the following applet parameters: forward, forwardtarget, forwardparameters, post,
postparameters, ziponfly, username, password, template
and resume. For instance, to update forward parameter:
document.fileupload.setProperty("forward","http://server.com/script.php");
- Any
other JavaScript method available ?
Yes, JFileUpload provides two methods allowing
to get info about uploads :
document.fileupload.getState(filename) returns WAITING,
INPROGRESS, COMPLETED, FAILED, CANCELLED string for
a given filename.
document.fileupload.getFilenames() returns a list
of filenames to upload.
You have a sample usage of the JavaScript API in samples/javascript_api/
- How
to get more traces for debug purposes ?
JFileUpload
uses Commons-Logging API. To enable DEBUG mode, just
copy/paste commons-logging.properties and simplelog.properties in the same directory as JFileUpload applet. Notice
that DEBUG mode will slow down applet execution so
NEVER enable DEBUG mode in production because JFileUpload
could use much CPU after a long time. Debug messages
will be displayed in the Java
Console.
- Can
I run JFileUpload from a CD-ROM or DVD ?
Yes. If you use "chunksize" and/or "ziponfly"
parameters then you should setup "tmpfolder"
parameter too because JFileUpload will generate
temporary files. tmpfolder="javatmpdir"
will generate temporary files in user's home folder
instead of selected files folder.
- Can
I scale images before upload ?
JFileUpload
provides a filter API to pre-process files to upload.
You could find an image scaling filter that generates
thumbnails (or magnify images) before upload in JFileUpload add-ons section.
- Can I queue files instead of uploading immediatly after selection ?
Yes, you need JBatchUpload plugin available in add-ons section.
- Can
I PGP encrypt files before upload ?
You
could find a PGP pre-processing filter that encrypts
files before upload in JFileUpload add-ons section.
- I'm
lost, where are the samples for basic and advanced
usages ?
Check out the samples/
folder in this documention.
- I
need to click on applet before using it, what's wrong
?
A recent update to Microsoft Internet Explorer 6 included a change
that alters the way users interact with applets in
the browser. Check out the samples/kb912945/ folder to fix this issue.
- JFileUpload
seems to ignore my settings, what's wrong ?
It might be a problem of JavaScript. If you mess
up the cross-browser JavaScript that displays applet
then some parameters may be skipped. Use copy/paste of an existing parameter to add new parameter.
- My
browser crashes when loading JFileUpload ?
We've have been reported that messed up JavaScript
could return a VC++ runtime error and crash Internet
Explorer on a few windows configuration. The solution
is to setup carefully the JavaScript file (copy/paste
existing line to add parameter).
- JFileUpload supports JRE 1.4+ but it requires to download JRE1.6?
Yes, for security and support reasons, default JavaScript setup of JFileUpload and add-ons is for Java 1.6 (or higher). If you do want 1.4 support then see JRE1.4+ in samples folder.
|
