Setting CLASSPATH for Java in Linux

This was really tough for me since I had never used command line for compiling java programs, I always used Netbeans for coding in Java. Recently I started learning JUnit for which I decided to use command Line.

Whenever I googled for its solution I got
$ export CLASSPATH=$CLASSPATH:

But this did not fix my problem. Eventually I landed up on some websites and finally here. Though it is mainly written for Windows but can be used likewise for linux also.

So the thing to be done is either add all the jar files explicitly to the classpath or put all the jars in a directory (/home/roshan/jars for me).

Now run this command:
$ export CLASSPATH=$CLASSPATH:/home/roshan/jars/*

The wildcard ‘*’ fixed the problem. Now you can make this change permanent by adding this command to your .bash_profile in home directory or /etc/profile to make system wide changes.

Running topcoder applet behind proxy

Somehow the default Iced Tea Webstart throws NullPointerException which I dont know how to debug. I downloaded SUN JDK and installed on my machine, you can use your package manager also. It usually gets installed in /usr/java/jdk-<version> and /usr/java/latest links to the latest version installed, so it is better to use the later. Then download the ContestApplet.jnlp and simply sun the following command to get it working.

$ /usr/java/latest/bin/javaws ContestApplet.jnlp

It uses default system proxy to download the content from Topcoder needed to execute the arena. When the arena is open set the proxy and use HTTP Tunnel A or B. For us Tunnel B works.

Quick update

These days I am quite busy with Drupal and have learnt that Drupal is not merely a blogging software, you can make a full fledged website out of it. You can make modules, themes, customise it, and much more than I used to think initially. Apart from that I have learned to use CSS which is also very important for web development. If you are trying to develop websites use Firebug extension from mozilla firefox, it is very useful and you can make your website look better. I am trying to integrate Drupal blogs module and planet module to make something which would let the client make a site which would give blogs from the site and blogs from wordpress, blogger etc stay together and would enable commenting. Apart from that I learned to use various other modules. In short this time Mukti website would be on Drupal not wordpress.

Apart from that I am learned something about XML-RPC module of Python. I have been longing for a desktop blogging software for Gnome. I tried some but they were not good. Now I think of making something.
In the mean time I have spent sometime with opendchub and have found a major flaw in the software, I think I will be able to fix it by this weekend (the only time I am free these days).

I have also made my first rpm for opendchub. I will very soon release rpms and debs for opendchub.

Lastly, I declare that I want to go to Agra, I need a companion, if somebody is willing please leave a comment . Everyone is invited.

How to /boot/grub/menu.lst for network install

Yesterday I went to help a Professor from Mechanical Department who had mailed me for help. He was really struggling with windows as desperately wanted to get Linux installed as he was not familiar with windows software. He was the first man I have ever met who said that he was struggling with office excel and wanted Linux.

He had an old HP workstation. I never had opportunity to see a workstation but yesterday I saw one and even installed Fedora 10 on it. I must say the machine was really fast even better than the new Centrino Duo / core 2 duo processors that we use. The instllaion took only 20 minutes and i must say here that he had nearly selected almost all the packages (GNOME & KDE both).

There was another machine whose DVD drive was not working. I had SUSE Enterprise Server installed with barely any software. So I installed openSUSE 11.1 on it from the Local Installation repository that we have. We generally use Unetbootin (Google if you dont know) for network installation. But I was not able to install that due to some dependencies. So I downlaoded the kernel and initrd filles from the installation medium and then i edited menu.lst.

• First I made a new directory in /boot and called it install.
• Then I copied the initrd and linux(kernel in opensuse DVD) to /boot/install.

• Then I edited menu.lst. Since my boot partition was same as root /dev/sda2, so for me i added

title Install

root (hd0,2)
kernel /boot/install/linux
initrd /boot/install/initrd

• Then I rebooted and selected “Install” from the boot menu and it worked out.

Once again it can be noticed how powerful Linux is, I dont know if any other OS gives you such options, if you know then please tell me 

using java on linux

This was a problem faced by my friend. He happens to use only JAVA that too JAVAC. He does not like to use Netbeans I don’t know why. And he said that it was the only problem that stopped him from using Linux. So I decided to help him. These were some links which were really helpful.

http://en.opensuse.org/Java
http://en.opensuse.org/Installing_Sun%27s_Java_on_SUSE_Linux (to be more precise)

The problem was that the openJDK which provides JAVC which is the default installation on openSUSE is different from JAVAC provided by SUN because the same Hello World program which compiled on SUN’s JAVAC failed to compile on openJDK’s JAVAC.

The details can be found out here http://lug.nitdgp.ac.in/wiki/index.php/How_to_use_Java_on_Linux

The repositories described there are Local to our college you can use your package manager to locate the packages. For openSUSE users sun’s packages are in Non-OSS repo

mouting network directory as your own directory, NFS

I manage our local GLUG server. And the server was running out of space. So I was thinking of some alternative, so NFS clicked my mind. I am trying to mirror Ubuntu repo for our college students.

There is another server in the college which I happen to manage, so I decided to give NFS a try. Since both the machines are running openSUSE the distro of my choice, it was not difficult at all. http://en.opensuse.org/NFS This link gave sufficient information about using NFS.

Within 10 minutes I was done. But I need to see how fast it actually is once the download completes. Hope it works out. Then our repo will be complete with support for Fedora, openSUSE and ubuntu. Check out the repo here. http://lug.nitdgp.ac.in/repository/

should i try fedora

Rangeen, who happens to be the only Fedora ambassador in our college did a very good work by creating a local Fedora repository http://lug.nitdgp.ac.in/repository/fedora-local/ . I am an openSUSE user and I am satisfied with it, we also have a local packman mirror http://lug.nitdgp.ac.in/repository/packman/ which happens to be the biggest repo for openSUSE. But the only problem is that it is not a complete repo, I mean while installing packages I need to download some packages from the internet also. But the Fedora repo which also has the updates is nearly a complete repo.

So I am thinking about trying Fedora now.

server administration is a difficult task

Just a week back I start to manage our GLUG server and since then it has turned out to be a nightmare for me. Every now and then something happens and people start pinging you. Whenever I go out and come to room I just type the url of the server on my browser to see if it is working. It adds a lot to your responsibilities.

I tried several distros and finally ended up with my favourite openSUSE, I find myself very much comfortable with it.

Some works to be done:
1. Fedora 10 repo
2. Ubuntu repo
3. Packman repo (we already have but it needs management)
4. More isos for download and for repo for network install

making direcories and symbolic links in apache web directory

This made me worried for the past two days. Thanks to IRC I got the solution.
Add these lines at the end of your default-server.conf file for apache. On opensuse it is in /etc/apache2/defualt-server.conf

<Directory “path to directory like /srv/www/htdocs/download”>
options Indexes Includes FollowSymLinks SymLinksifOwnerMatch ExecCGI MultiViews
AllowOverride All
Order allow,deny

Allow from all

</Directory>

Then restart apache.
This makes the directory visible from web browser and makes apache follow symbolic links !
This was really painful yet the answer was so simple.
I need to look in apache configurations properly.

setting up an SVN server is as easy as eating cake

I tried to set up an svn server on my laptop today as I have organized a hack session today to bring in more people for hacking FOSS.
I have chosen opendchub for three reasons:
1. They have seen it working. And they actually use it.
2. The source code is as less as 10 c files.
3. The project is dead. I have already applied for the maintainership. You dont apply please

This is a helpful link href=”http://en.opensuse.org/Setting_up_a_Subversion_server_using_Apache2 . I hope everything turns out positively.