I'm looking into a small project just now where we have a need for a very very basic news article system. Ideally, this is a simple XML file that will be written to with some news, and then parsed to display on the homepage. This file is on the server, of course.
My question is how to allow a client browser to write to this XML file, given that the server will not have PHP enabled?
I know of TiddlyWiki which uses a .JAR file to allow the writes, but are there any other methods I should try?
Since FTP seems to be enabled/supported, your best bet is to create an applet which does the job. FTP connectivity can fairly simple be done by Apache Commons Net FTPClient. Your only problem is that the FTP connection details needs to be embedded in the applet somehow and that anyone with bad intent can extract it from the applet's source code since applets are downloaded into the client machine.
Without some serverside code, you will not be able to write files to the server.
You need a "PHP/Java/FTP-Server/something else"-backend serverprocess to take the content and write it to a file.
Apache supports HTTP PUT, and some browsers support it in XMLHttpRequest. So long as you are willing to limit editors to browsers that support it, you could use that without installing additional software on the server or using a plugin on the client.
FTP would definitely work, depending on how well the user doing the updates is familiar with it.
If the upload solution needs to be browser-based, you could perhaps run an FTP applet and have the user remember the connection details/password.
Related
I am new in java web application, (Java EE, JSF).
I tried to change the contents of a csv file on the client computer with a java web application, so that the client does not have to download a new file, because the file is already in the set to be used for applications in the client. so I just wanted to rewrite the csv file.
Could it be done in java web application? If yes, please give me an example. I am very grateful if there is a better solution.
No, absolutely not. You can't change the contents of a file on a client computer from a web browser. The best you could do is have them upload a version of a file and then send them another version to download. Giving write access to the filesystem would be a massive security hole.
Place the CSV on a network share somewhere. The client can edit it, the back-end server can edit it. Requires more infrastructure, of course, but may work depending on the type of application.
Not that I think this is what you want, but if the 'client computer' was also acting as the server (i.e. was the host running Jetty/Tomcat/whatever), then you could modify files on it using the java IO api.
Again, very likely not what you want, just saying it would work.
I would like to write a web application (in django) which scans the client/remote computers (assumption is windows) and retrieve the list of software's(mainly browsers) installed. Looking for suggestions to implement it.
Is this possible without asking the user to download any scritps/exe's?
If so, is it possible via java script?
I am planning to use python/django to write the entire app. Any input would be much appreciated.
EDIT : Comments on feasibility in java also much appreciated
Short answer: No, it is not possible
Long answer: This is something that any sane (operating) system designer / administrator would try to prevent - scanning of local system by a web page. However, you could use a plug-in component, such as a java applet, to do so - but in practice you probably would need to handle each client platform (OS) separately, since each of them has a different way of storing the information of installed software
You want to access the data from the client side so from the conceptual/logically its not good to access the client system. You have to use some medium which run on client side on behalf of server.
JavaScript and JavaApplet is good in this. You can get the data by JavaScript or Applet and in backend you can send data to the server.
You cannot do this unless you have some signed control installed on the client computer; or have them download a program which runs (separate from a browser) and sends the information to your server, where your django app can access it.
This is not possible using javascript (as it runs in a sandbox).
"Scanning" a client from a server may be possible if you break their security or get them to break it for you through some extension (see windows udate, for example). Either way, it's evil.
I'm writing a program that will be hosted on GAE that can upload and process local files. The program needs to process the file on the server side, and then return it to the client side. Previously I used JFileChooser for that purpose, but found out that it's not supported in GAE. I did some research and found FileUpload class, but it seems like it can't return the data to the client side. I could just let the user type the path of the file, but that would be just bad usability.
Any ideas are appreciated! Thanks.
GAE may not support JFileChooser directly, but it is apparently possible to embed applets.
Since that is the case:
A digitally signed and trusted applet can show a JFileChooser.
A sand-boxed applet deployed in a Plug-In 2 architecture JRE (e.g. Sun's 1.6.0_10+) can be launched using Java Web Start and use the services of the JNLP API. The JNLP API offers the FileContents object by way of the FileOpenService. Here is a small demo. of the file services of the API.
You can't upload files to appengine in the conventional way. There is no filesystem. You have to serialize them into the datastore.
I have exported some Processing code (outputs sensor data to a textbox) to an
applet that includes the .jar and .html files. I have tried to insert this html on a
simple website that I created and the java applet doesn't work. Do I have to somehow
modify the html? I know that the .jar files are already in the same directory and
are referenced appropriately in the exported html code. Is there a better approach
to posting to a website? Thank you
I don't think that it is possible, due to security restrictions on applet communication.
More than likely you will have to write a small client/server program using sockets.
The idea would be to transmit the the output from your locally running client application to your applet(server) which would receive and display the data.
You could use any language with socket support obviously(Flash, PHP, etc.), but I assume you will want to stick with Java.
I've been tasked with implementing large (2gb+) file uploads via a web browser. After evaluating various technologies, java applets seem to be the way forward (only one's which provide proper access to the local disk). I was wondering if anyone can recommend a 3rd party file upload app we can use as a base? requirements are
Decent UI, ideally we want something similar to facebooks photo uploader
Can handle large (2gb+) files
Resumable uploads
We beed the source to extend it to our needs (dont mind paying extra)
You're probably looking for JUpload.
Update: not sure if it has as nice of UI as you're hoping, but unless you want to build a custom solution like I have it's your best option.
Just a tip, maybe it is obvious, i don't know :P
It is nice to send the big file in chunks like 2mb, and on the server side you just append the bytes to the target file. The server knows what bytes it needs, and if a upload is aborted and continued later, the server can just send a message about from what bytes to start uploading the file again. Then we get resumability (is it a word? :P) and safety of large HTTP-uploads (since, in fact, we are sending many smuller uploads, and each upload is checked to be of the correct size on the server).
We wrote an implementation like this once with a Java-applet as the client and PHP on the server, I'll see if I can dig it out as a reference for you :p
Not really a solution : from experience you may bump into the following issues:
problems when uploading over HTTPs
problems uploading through proxies
Just wanted to make you aware of these two cases, for you to test when evaluating a solution.
Hope, you will get solutions for your prob over here.. http://jupload.sourceforge.net/