Re: Web upload of a Java class
Storm Linux User wrote: It's not form commercial use. It's for my research project for getting my master's degree in Electrical Engineering ... I'm not concered about securety right now. Hmm as long as you're not pursueing a masters in computer security.. Take a look at http://www.servlets.com and get the /com/oreilly/servlet package. It contains a class called MultiPartRequest, which should help you upload the file to your server. Then all you should do is have your servlet copy the file from te location from where it was uploaded to the location from where you can run the classfile.. It's quite dangerous thou ;-) sven -- == Sven E. van 't Veer http://www.cachoeiro.net Java Developer [EMAIL PROTECTED] ==
RE: Web upload of a Java class
This sounds dangerous. Why would you want to do it? -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Storm Linux User Sent: Saturday, November 11, 2000 6:55 AM To: Orion-Interest Subject: Re: Web upload of a Java class I mean it's showed to the user a HTML form that the user of the application can select I file to upload. It can be any file, to store in the application database, or even a java class. In the last case, instead of putting it into the database, the application will execute some methods of the class. I wish I'm more clear now Thanks. Guilherme Ceschiatti On Friday 10 November 2000 19:24, you wrote: Sorry..not sure I understand? Do you mean "deploy" it into an application server, so that it immediately takes affect and then you can use it right away? If so, look at the .WAR format, or .EAR format. Its a J2EE standard format and most app servers should provide some sort of hot-swap application deployment capability. You simply upload the .war or .ear, and the app server serializes all HttpSession objects to disk (or some place), then reloads the app with the new class(es), then reads the serialized objects back into the HttpSession. This makes it appear to clients that nothing is different, but your new class(es) will be available. -Original Message- From: Storm Linux User [mailto:[EMAIL PROTECTED]] Sent: Friday, November 10, 2000 10:46 AM To: Orion-Interest Subject: Web upload of a Java class Hi... I need to upload a compiled class to my Orion application and then execute some methods of it. Anybody knows how can I do it? []s Guilherme Ceschiatti [EMAIL PROTECTED]
Re: Web upload of a Java class
It's not form commercial use. It's for my research project for getting my master's degree in Electrical Engineering ... I'm not concered about securety right now. []s Guilherme Ceschiatti [EMAIL PROTECTED] On Sunday 12 November 2000 12:41, you wrote: This sounds dangerous. Why would you want to do it? I mean it's showed to the user a HTML form that the user of the application can select I file to upload. It can be any file, to store in the application database, or even a java class. In the last case, instead of putting it into the database, the application will execute some methods of the class. I wish I'm more clear now Thanks. Guilherme Ceschiatti On Friday 10 November 2000 19:24, you wrote: Sorry..not sure I understand? Do you mean "deploy" it into an application server, so that it immediately takes affect and then you can use it right away? If so, look at the .WAR format, or .EAR format. Its a J2EE standard format and most app servers should provide some sort of hot-swap application deployment capability. You simply upload the .war or .ear, and the app server serializes all HttpSession objects to disk (or some place), then reloads the app with the new class(es), then reads the serialized objects back into the HttpSession. This makes it appear to clients that nothing is different, but your new class(es) will be available. -Original Message- From: Storm Linux User [mailto:[EMAIL PROTECTED]] Sent: Friday, November 10, 2000 10:46 AM To: Orion-Interest Subject: Web upload of a Java class Hi... I need to upload a compiled class to my Orion application and then execute some methods of it. Anybody knows how can I do it? []s Guilherme Ceschiatti [EMAIL PROTECTED]
Re: Web upload of a Java class
At 15:00 12.11.00 , you wrote: It's not form commercial use. It's for my research project for getting my master's degree in Electrical Engineering ... I'm not concered about securety right now. then hack right on. will be fun. the security aspects of this could easily fill a chapter of your thesis if it fits your topic ;-). robert (-) Robert Krüger (-) SIGNAL 7 Gesellschaft für Informationstechnologie mbH (-) Brüder-Knauß-Str. 79 - 64285 Darmstadt, (-) Tel: 06151 665401, Fax: 06151 665373 (-) [EMAIL PROTECTED], www.signal7.de
Re: Web upload of a Java class
I'm using the HTML form input type="file" name="my_file" to upload
my compiled class file. When I try to get the file in the servlet, using:
File f = (File)request.getParameter("my_file");
It does not work. I need to get the class file, generate an object of it and
then execute some methods.
How can I do this?
[]s
Guilherme Ceschiatti
[EMAIL PROTECTED]
Hi...
I need to upload a compiled class to my Orion application and then execute
some methods of it. Anybody knows how can I do it?
upload the class file, instantiate a URLClassloader that points to the
file's url, load the class using that classloader, do whatever you need
using reflection (e.g. instantiate objects, call methods on them, whatever)
and after that dump the classloader.
however as simple as that may be, are you aware of the security
implications of this? if this is not just for playing around, you should
read up on java security and classloading and then subclass URLClassLoader
and implement a very restrictive getPermissions() method for the uploaded
code.
before you do that be REALLY, REALLY sure you know what you are doing if
this is for real world use!!!
other than that I don't see any difficulties in achieving what you
described.
HTH,
robert
[]s
Guilherme Ceschiatti
[EMAIL PROTECTED]
(-) Robert Krüger
(-) SIGNAL 7 Gesellschaft für Informationstechnologie mbH
(-) Brüder-Knauß-Str. 79 - 64285 Darmstadt,
(-) Tel: 06151 665401, Fax: 06151 665373
(-) [EMAIL PROTECTED], www.signal7.de
Re: Web upload of a Java class
oh, I see. that's something the servlet api doesn't do for you. to parse a
multipart request (that's what you use for file-upload) all you get is an
input stream that you can parse which you have to decode. however there are
plenty of utilities that do this for you. one is even shipped with orion.
check the api docs for FilePostParser. there is a source example of how to
use it.
just get the request input stream, apply the parser to it (again gives you
input stream on the decoded data items) and store copy the data from the
input stream to a file.
remember to set the form enctype to multipart/form-data.
that should be all you need to get going.
robert
At 17:33 12.11.00 , you wrote:
I'm using the HTML form input type="file" name="my_file" to upload
my compiled class file. When I try to get the file in the servlet, using:
File f = (File)request.getParameter("my_file");
It does not work. I need to get the class file, generate an object of it and
then execute some methods.
How can I do this?
[]s
Guilherme Ceschiatti
[EMAIL PROTECTED]
(-) Robert Krüger
(-) SIGNAL 7 Gesellschaft für Informationstechnologie mbH
(-) Brüder-Knauß-Str. 79 - 64285 Darmstadt,
(-) Tel: 06151 665401, Fax: 06151 665373
(-) [EMAIL PROTECTED], www.signal7.de
Re: Web upload of a Java class
At 16:45 10.11.00 , you wrote: Hi... I need to upload a compiled class to my Orion application and then execute some methods of it. Anybody knows how can I do it? upload the class file, instantiate a URLClassloader that points to the file's url, load the class using that classloader, do whatever you need using reflection (e.g. instantiate objects, call methods on them, whatever) and after that dump the classloader. however as simple as that may be, are you aware of the security implications of this? if this is not just for playing around, you should read up on java security and classloading and then subclass URLClassLoader and implement a very restrictive getPermissions() method for the uploaded code. before you do that be REALLY, REALLY sure you know what you are doing if this is for real world use!!! other than that I don't see any difficulties in achieving what you described. HTH, robert []s Guilherme Ceschiatti [EMAIL PROTECTED] (-) Robert Krüger (-) SIGNAL 7 Gesellschaft für Informationstechnologie mbH (-) Brüder-Knauß-Str. 79 - 64285 Darmstadt, (-) Tel: 06151 665401, Fax: 06151 665373 (-) [EMAIL PROTECTED], www.signal7.de
Web upload of a Java class
Hi... I need to upload a compiled class to my Orion application and then execute some methods of it. Anybody knows how can I do it? []s Guilherme Ceschiatti [EMAIL PROTECTED]
RE: Web upload of a Java class
Sorry..not sure I understand? Do you mean "deploy" it into an application server, so that it immediately takes affect and then you can use it right away? If so, look at the .WAR format, or .EAR format. Its a J2EE standard format and most app servers should provide some sort of hot-swap application deployment capability. You simply upload the .war or .ear, and the app server serializes all HttpSession objects to disk (or some place), then reloads the app with the new class(es), then reads the serialized objects back into the HttpSession. This makes it appear to clients that nothing is different, but your new class(es) will be available. -Original Message- From: Storm Linux User [mailto:[EMAIL PROTECTED]] Sent: Friday, November 10, 2000 10:46 AM To: Orion-Interest Subject: Web upload of a Java class Hi... I need to upload a compiled class to my Orion application and then execute some methods of it. Anybody knows how can I do it? []s Guilherme Ceschiatti [EMAIL PROTECTED]
