Eclipse : Java was started but returned exit code = -1

I was having eclipse on my system (eclipse 3.6 – helios version), and a week ago, I decided to set it up for doing Android programming in Java.

When I opened Eclipse, I got the following error :

Java was started but returned Exit Code = -1

The error was same as shown in this image ( i have taken this image from the world wide web )

I googled this error and found that many people had faced the same error and there were many solutions available to this problem.

Most Common Solution : One of the most common solution that I found was of adding some lines to eclipse.ini file, For example: The path to the javaw.exe file. Adding some arguments to eclipse.ini file was also suggested.

This solution had solved the problem of many people, but, it lead to some other errors in my case( example : unable to find java virtual machine on the specified path).

I tried re-installing eclipse but the problem remained as it is.

Then, I decided to re-install my jdk and jre to the latest versions that were available.

I removed all the older versions and re-installed latest available versions of jdk and jre.

When I tried starting eclipse again, it started.

This solved my problem 🙂

If you are facing the same problem, then I suggest you give it a try once to re-install jdk and jre, and, see if it can help.

All the best!! 🙂

App Inventor : Blocks editor opens but it’s blank, work lost

Hi!

I making an app that will enable people who are deaf-blind to send and receive sms. I have been using App Inventor for quite some time now, and, I am using it for making an initial version of that app.

In this post I will be discussing about a problem that I faced in App Inventor while making the app, and, I will also discuss it’s solution.

Problem : I designed and programmed the app using web browser Firefox in the afternoon. When I tried to load it at night, the Blocks editor opened, but, it was all blank, and, all the work that I had done had vanished.

Solution : Close the browser in which you tried opening the blocks editor using App Inventor initially, and, try opening using another browser.

In my case, I case I opened the app using Firefox initially, but, after the error occurred, I shifted to Chrome and everything worked fine.

Caution : Don’t open App Inventor in two browsers at the same time, as, you can lose your work in such a situation.

All the best … Happy Learning 🙂

Using Derby database in Netbeans IDE

I was working on my project, “Public Distribution System”, and, I needed to use a database to store and retrieve data from the database. I tried the Type 1 connectivity with SQL Server, but, was unsuccessful.

I tried to correct the problem for around 10 days, by trying almost each and every solution given on the internet, but, none proved fruitful.

Some of my batch-mates were also unsuccessful in setting up Type1 connection, and, I am not sure if it was a coincidence or not, but, all of us were having Windows 7 OS (64-bit version) on our laptops.

Then I decided to go with Type 4 connectivity in Java, and, while I was searching tutorials for the same, I came across a tutorial explaining  how to use Derby database  in Netbeans.

The tutorial link is as follows :
http://netbeans.org/kb/docs/ide/java-db.html

This link was easy to grasp and has explained the using of database in a stepwise manner.

So, if you are also stuck in setting up a database connection, then, I hope my post will help in providing a solution to your problem.

All the best 🙂

General Elections ’09

vote_Ti1N1_17334

Good Morning ! 🙂

It’s 0745 hrs in the morning and I have a very important work to do today; I have to cast my vote and play my part in choosing the next Government of India 🙂

This is the first time I will cast my vote in General Elections and overall second time beacause 5-6 months back I had cast my vote for the first time in Delhi Legislative Assembly polls.

I felt very nice after casting my first vote and even nicer when the party I had voted for i.e. Indian National Congress formed the government in Delhi for the third successive time.

You too, go out and Vote and take pride in being an INDIAN.

Installing Secondlife on Linux

Few days ago I formatted my laptop and again made it a dual boot, but this time around I installed Ubuntu 8.10 instead of Kubuntu’s latest version and fell in love with it. I never liked Gnome but this time I couldn’t leave Gnome, even though Kubuntu with exciting features of KDE 4.1 was also attracting me. So, as I was re-installing my softwares, I thought that I should install Secondlife on linux instead of Vista(as I seldom use Vista anymore), even though I was unsuccessful last time.

Step 1 : Download the tar.bz2 file from http://secondlife.com/support/downloads.php.

sl

Step 2 : Now use your file manager to reach to the location where the file has been saved and extract it by using an archive     manager by double clicking on it .

sl2

Step 3 : After extracting move to the location where you have extracted the contents and double click the file named “secondlife” and choose the option “run” to run the file.

sl3

sl4

Step 4 : Enjoy your stay at the Virtual World.

sl5

This is the GUI approach of installing Secondlife on Linux, you can also install it by using the commandline.

Command line version of SL install on Linux :

Step1 : Download the tar.bz2 file from http://secondlife.com/support/downloads.php.

Step2 : Move to the location where you saved the above downloaded file and then type the following command

anmol@anmol-laptop:~$ cd sl

In place of  “sl” the name of the folder where you downloaded the file.

anmol@anmol-laptop:~/sl$ tar xvf SecondLife-i686-1.21.6.99587.tar.bz2

Instead of “SecondLife-i686-1.21.6.99587.tar.bz2”, type the name of the file that you have downloaded.

Step3: Move to the extracted folder using “cd” command and then on the terminal type “./secondlife” to start SL . Steps are shown below.

anmol@anmol-laptop:~/sl$ ls
SecondLife-i686-1.21.6.99587  SecondLife-i686-1.21.6.99587.tar.bz2
anmol@anmol-laptop:~/sl$ cd SecondLife-i686-1.21.6.99587/
anmol@anmol-laptop:~/sl/SecondLife-i686-1.21.6.99587$ ./secondlife

I hope, you’ll be able to install Secondlife on your linux distro and enjoy your Secondlife to the fullest.  😀

RoR: WARN TCPServer Error: Address already in use

I got the following error, when I started the rails server:

anmol@anmol-laptop:~/workshop$ ruby script/server
/usr/lib/ruby/1.8/xmlsimple.rb:275: warning: already initialized constant KNOWN_OPTIONS
/usr/lib/ruby/1.8/xmlsimple.rb:280: warning: already initialized constant DEF_KEY_ATTRIBUTES
/usr/lib/ruby/1.8/xmlsimple.rb:281: warning: already initialized constant DEF_ROOT_NAME
/usr/lib/ruby/1.8/xmlsimple.rb:282: warning: already initialized constant DEF_CONTENT_KEY
/usr/lib/ruby/1.8/xmlsimple.rb:283: warning: already initialized constant DEF_XML_DECLARATION
/usr/lib/ruby/1.8/xmlsimple.rb:284: warning: already initialized constant DEF_ANONYMOUS_TAG
/usr/lib/ruby/1.8/xmlsimple.rb:285: warning: already initialized constant DEF_FORCE_ARRAY
/usr/lib/ruby/1.8/xmlsimple.rb:286: warning: already initialized constant DEF_INDENTATION
/usr/lib/ruby/1.8/xmlsimple.rb:287: warning: already initialized constant DEF_KEY_TO_SYMBOL
=> Booting WEBrick…
=> Rails 2.1.0 application started on http://127.0.0.1:3000
=> Ctrl-C to shutdown server; call with –help for options
[2009-01-25 20:42:49] INFO  WEBrick 1.3.1
[2009-01-25 20:42:49] INFO  ruby 1.8.7 (2008-08-11) [i486-linux]
[2009-01-25 20:42:49] WARN  TCPServer Error: Address already in use – bind(2)
/usr/lib/ruby/1.8/webrick/utils.rb:73:in `initialize’: Address already in use – bind(2) (Errno::EADDRINUSE)
from /usr/lib/ruby/1.8/webrick/utils.rb:73:in `new’
from /usr/lib/ruby/1.8/webrick/utils.rb:73:in `create_listeners’
from /usr/lib/ruby/1.8/webrick/utils.rb:70:in `each’
from /usr/lib/ruby/1.8/webrick/utils.rb:70:in `create_listeners’
from /usr/lib/ruby/1.8/webrick/server.rb:75:in `listen’
from /usr/lib/ruby/1.8/webrick/server.rb:63:in `initialize’
from /usr/lib/ruby/1.8/webrick/httpserver.rb:24:in `initialize’
from /home/anmol/workshop/vendor/rails/railties/lib/webrick_server.rb:58:in `new’
from /home/anmol/workshop/vendor/rails/railties/lib/webrick_server.rb:58:in `dispatch’
from /home/anmol/workshop/vendor/rails/railties/lib/commands/servers/webrick.rb:66
from /usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require’
from /usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `require’
from /home/anmol/workshop/vendor/rails/activesupport/lib/active_support/dependencies.rb:509:in `require’
from /home/anmol/workshop/vendor/rails/activesupport/lib/active_support/dependencies.rb:354:in `new_constants_in’
from /home/anmol/workshop/vendor/rails/activesupport/lib/active_support/dependencies.rb:509:in `require’
from /home/anmol/workshop/vendor/rails/railties/lib/commands/server.rb:39
from /usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require’
from /usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `require’
from script/server:3

It seems that port 3000 is already in use . Try using the command mentioned below and see if it works :

ruby script/server -e production -p 3001

if the server starts then go the page : http://yourhost:3001/ .

I hope this will solve the problem.

/usr/bin/gem:23:uninitialized constant Gem::GemRunner(NameError)

I came across this error when I tried to update my RubyGems because my Rails wanted version 1.3.1 and I was having 1.2.0.

When I wrote  “sudo gem update –system” on the terminal I came across the following error :

/usr/bin/gem:23: uninitialized constant Gem::GemRunner(NameError)

So the solution is to add require ‘rubygems/gem_runner’ line to  /usr/bin/gem . If you don’t know how to do this or if you are a newbie, don’t  worry, I am explaining it below .

Step 1 : Go to the terminal and type the following

$ cd /usr/bin/

This will move you to the folder  /usr/bin/

Step 2 : Type the following command to open up file in text editor

$ sudo pico gem    and enter your password

Step 3 : Add the line ‘rubygems/gem_runner’ to the gem file that opens up after Step 2 ,

Add the line before  require ‘rubygems’
Step 4 : Press Ctrl+X to save the file and exit

4a) Press ‘Y’ if you think you have done the relevant changes correctly and want to save the file. Otherwise,

Press ‘N’ and move out without saving.

4b) If you press ‘Y’ in the previous step, it will ask you if you want to save the file with same name? , Just

press ‘Enter’ and move out.

I hope this solution will help you to solve your problem. I was successful in solving my problem on my Ubuntu 8.04.


Skid Software launch and my Presentation at India International Centre(IIC),New Delhi

On 10 October 2008, Skid software was officially launched at the India International Centre, New Delhi, India. In this launch Dr.Arun Mehta told people about the problems with which an Autistic child suffers from and also about the inaction on the government’s part.

All the people who had gathered there were shown the video of Arpit (whose blog is in my blogroll),an Autistic child, using the Skid software with the help of a gaming wheel. You can see the video below

You can see Arpit using the gaming wheel in the above video.

Arpit was also there at the function.

I was also given a chance to demo my cropping and picedit modules at IIC, main hall . First, I gave demo of my crop module and showed them by cropping a picture . Next I demonstrated the picedit module and as soon as people saw the border being added to the picture i realised  they understood the whole working as there were reactions from the audience.

One autistic girl from the audience came up the stage and tried her hand at the Skid software. The girl did some typing with the help of the gaming wheel and looked very excited and happy with the software.

All in all it was a great learning experience as it was the largest gathering in front of whom I have given a presentation and also an honour to speak at the India International Centre, Main Hall .

Anmol Anand : Web Designer

In my last post I had written code for cropping an image using Ruby and Rmagick and I had mentioned that I was working upon a simple picture editor for Skid software, which is a software(web site) designed for people with Autism,cerebral palsy, dyslexia or anyone who has a problem with keyboard or mouse. .

I have not written any post on my blog for quite some time now, as I was waiting for something significant to happen so that I can talk about it. So, I have completed my share of work for Skid software and developed two modules, instead of one, which was planned earlier.

My first module is “Crop module” which was developed in the Expert Guidance of Prof. Arun Mehta. The crop module allows you to have some fun with pictures, It allows you to crop a picture from all sides i.e. ‘left’,’right’,’top’ and ‘bottom’. The crop module works in conjunction with picbrowser module. First, you have to select a picture from the picbrowser module and then move to the crop module. On moving to the crop module, first select the side from where you want to crop the picture i.e. ‘left’,’right’,’top’ and ‘bottom’ and by the help of up and down arrow buttons increase or decrease the amount of cropping. After doing the desired cropping, save the picture by clicking the smiley and your picture will be saved in the relevant directory.

There is a special way in which we save the names of the files that are cropped and finalised by the users.For example:

If you select a picture of ‘Football.jpg’ and then you go to the crop module and perform 40% cropping from right and save it, the name of the new cropped file will be ‘Footballcr40‘.jpg, meaning Football.jpg croped 40% from right. Each time you perform a new operation on a picture, it’s abbreviation is appended to the name of the orignal file and saved.

left crop – cl

right crop – cr

top crop – ct

bottom crop – cb

A picture of crop moule on www.skid.org.in

A picture of crop moule on http://www.skid.org.in

Above picture cropped 60% from left with help of crop module

Above picture cropped 60% from left with help of crop module

Now, let me talk about the second module which was made independently by me, after Prof Arun Mehta taught me how to go about the process, during making of crop module. This module is the ‘picedit’ module. This module lets you to have even more fun with pictures by allowing you to add effects such as border, wave, blur, radialblur, rotate and charcoal effect to the picture you have selected. The methodology is the same, first go to picbrowser, select the picture on which you want to add picture effects. Once you have selected the picture, move on to the picedit module and select the effect which you want to add to the picture. Once you have selected the effect, increase or decrease the amount of effect with the help of up and down buttons on the left side of the page. When you are done with your work, save the picture by pressing the select button.

Again, there is a special way in which we save the name of the files that are cropped and finalised by the users. For example: If you select the picture of ‘Football.jpg’ and then you go to picedit module and add a border of 40 pixels to the image and save it, the name of the new file will be ‘Footballb40.jpg’ meaning Football.jpg has been added with 40 pixel border. Each time you perform a new operation on a picture, it’s abbreviation is appended to the name of the orignal file and saved.

border – b

wave – w

rotate – rot

blur – bl

radialblur – rdb

charcoal – co

picedit module showing wave effect in the flower image

picedit module showing wave effect in the flower image

You can go and try the software on http://www.skid.org.in and apart from this module there are wikipedia module, email module etc.

I would like to thank God and my Parents who have helped me and supported me throughout the period of making of these modules and also given me strength when my spirits were down.

Once again I would like to thank Prof Arun Mehta for giving me a chance and making me part of this noble mission to help Autistic Children and also giving me guidance and support throughout the period of making these modules and also when I was struck with errors in the program .

Thank you all !!!!

Crop an Image using Ruby and Rmagick

#!/usr/local/bin/ruby -w
require ‘RMagick’
include Magick

puts “Please enter the path of the file for which you want to perform cropping(complete path with file extension) :: \n ”
path=gets #gets the path from the user

puts “The file path specified by you is as follows :: \n ”
puts path.inspect #prints the user given path on the scrreen

path = path.chomp #this command helps remove the newline in the end of path to make it executable for Image.read()
img = Magick::Image.read(path).first #reads the image specfied by the user path

thumb = img.scale(640,480) #scales image to 640×480

puts ” Please choose the option
1 = Crop from left
2 = Crop from right
3 = Crop from top
4 = Crop from bottom ”

choice = gets #gets the user choice of cropping
choice=choice.to_i #converts the choice to integer by to_i so that it can be used in following case statement

puts “please specify the percentage that has to be cropped ”
percentcrop = gets #gets the percentage that has to be cropped from left,right,top,bottom choosen by user
percentcrop = percentcrop.to_i #converts the user entered percentage to integer
percent = percentcrop/100.0 #divides it by 100 so that it can be used for specifing new width and height of the pic

width = 640 ; #width of the pic (in pixels)
height = 480; #height of the pic (pixels)

widthchanged = (width*percent) #new width (based on the percentage specified by the user)
#widthchanged =widthchanged.to_i

heightchanged = (height*percent) #new height (based on the percentage of cropping specified by the user)
#heightchanged = heightchanged.to_i

case choice
when 1
final=thumb.crop(NorthWestGravity,widthchanged,height).write”/home/anmol/blogimage.jpg” #writes the cropped image into a file
final.display #displays the final cropped image
when 2
final=thumb.crop(NorthEastGravity,widthchanged,height).write”/home/anmol/blogimage.jpg” #writes the cropped image into a file
final.display #displays the final cropped image
when 3
final=thumb.crop(NorthWestGravity,width,heightchanged).write”/home/anmol/blogimage.jpg” #writes the cropped image into a file
final.display #displays the final cropped image
when 4
final=thumb.crop(SouthEastGravity,width,heightchanged).write”/home/anmol/blogimage.jpg” #writes the cropped image into a file
final.display #displays the final cropped image
else
puts “No cropping is performed”
final=thumb.write”/home/anmol/blogimage.jpg” #writes the cropped image into a file
final.display #displays the final cropped image
end

This program is the refined version of the previous crop program that I wrote . This program is basically performing cropping on a file specified by the user from four sides left,right,top and bottom according to the percentage specified by the user .

Now I am working on incorporating this program into skid website as a crop module using Ruby on Rails(RoR) . So below are some pictures which show how user can use this program to crop a desired picture.

the starting image

the starting image

cropped from left 60%

cropped from right 60%

cropped from right 60%

cropped from left 60%

cropped from top 66%

cropped from bottom 66%

cropped from bottom 66 %

cropped from top 66 %

Ruby and Rails Tutorials

I am giving url of sites that are either books , tutorials or simply a help in form of video , audio and refcards to learn Ruby and Rails.

Ruby :

Online Guide : The Pragmatic Programmers Guide (Picaxe Guide)

Site-point

Book : The Ruby Cookbook

Ruby Learning through flashcards : YoYoBrain

Online Tutorial : Meshplex Tutorial

Rails : In this section I have been able to find video tutorials only .

Video tutorial : Learning Rails

Video Tutorial : Railscasts

PS : I will try to update the list if I am able to find other good tutorials . Otherwise , there are very good books available in the market which help the cause of learning ruby and rails and I will try to name a few which I know in one of my following posts

Enjoy Learning !!! 😀

Ruby program to scale and crop an Image using Rmagick


#!/usr/local/bin/ruby -w
require ‘RMagick’
include Magick

img = Magick::Image.read(‘/home/anmol/jack.jpg’).first # path of Orignal image that has to be worked upon
puts img.inspect

def try(x,y,width,height)


# converting x,y , width and height to integer values in next four statements
x= x.to_i
y= y.to_i
width= width.to_i
height= height.to_i

# Demonstrate the Image#crop method
@st = ‘/home/anmol/tempimage.jpg’ # path of image written after changing size or not changing also
img = Magick::Image.read(@st)[0]

# Crop the specified rectangle out of the img.
chopped = img.crop(x, y, width,height)

# Go back to the original and highlight the area
# corresponding to the retained rectangle.
rect = Magick::Draw.new
rect.stroke(‘transparent’)
rect.fill(‘black’)
rect.fill_opacity(1.0)
rect.rectangle(x, y, 100+x, 10+y)
rect.draw(img)

img.write(‘/home/anmol/imgbeforecrop.jpg’) #path of image written before cropping

# Create a image to use as a background for
# the “after” image.
bg = Magick::Image.new(img.columns, img.rows)

# Composite the the “after” (chopped) image on the background
bg = bg.composite(chopped, 38,81, Magick::OverCompositeOp)

bg.write(‘/home/anmol/imgaftercrop.jpg’) # path of image written after cropping the desired part

exit

end

puts “Please enter ::
1 = Making image one-fourth of it’s orignal size
2 = Making image half of it’s orignal size
3 = Making image three-fourth of it’s orignal size
4 = Minfing the image
5 = Magnfing the image \n”

print “option selected = ” ; option = gets
option = option.to_i

puts “Please enter x co=ordinate , y co-ordinate , width and height from x and y co-ordinates of the portion that is to be cropped [ALL THE FOUR VALUES TO BE NUMERIC VALUES AND GREATER THAN ZERO] “

print “x co-ordinate ” ; xc= gets ;
print “y co-ordinate ” ; yc= gets ;
print “width ” ; w= gets ;
print “height ” ; h= gets ;

case option
when 1
thumb = img.scale(0.25) #scale image to 25 % of it’s orignal size
thumb.write “/home/anmol/tempimage.jpg”
# path of image written after changing size or not changing also
puts thumb.inspect
try(xc,yc,w,h)

when 2
thumb = img.scale(0.50) #scale image to 50 % of it’s orignal size
thumb.write “/home/anmol/tempimage.jpg”
# path of image written after changing size or not changing also
puts thumb.inspect
try(xc,yc,w,h)

when 3
thumb = img.scale(0.75) #scale image to 75 % of it’s orignal size
thumb.write “/home/anmol/tempimage.jpg”
# path of image written after changing size or not changing also
puts thumb.inspect
try(xc,yc,w,h)

when 4
thumb = img.minify # minify the image
thumb.write “/home/anmol/tempimage.jpg”
# path of image written after changing size or not changing also
puts thumb.inspect
try(xc,yc,w,h)

when 5
thumb = img.magnify #magnify the image
thumb.write “/home/anmol/tempimage.jpg”
# path of image written after changing size or not changing also
try(xc,yc,w,h)

else
puts “the image will remain in it’s orignal size ”
thumb = img
thumb.write “/home/anmol/tempimage.jpg” # path of image written after changing size or not changing also
try(xc,yc,w,h)

end

I said in the last post that I am working on Simple Picture editor for Skid software , So I have posted a liitle bit of code which I have written in Ruby , it’s a small step and a lot has to be done .

This program first asks user weather he/she wants to change the size of the image to one-fourth of it’s orignal size , minify it , magnify it etc . After you specify the size , user is asked about the dimension of the rectangle which is to be cropped from the image . After specifing the rectangle dimension , the image cropped image is written .The program produces 3 images , first image is tempimage.jpg which is created if user agrees to change the size of the image ; second image is imgbeforecrop.jpg which specifies the rectanglular portion in the image which will cropped by blackening that particular portion of the image ; third image is the imgaftercrop.jpg which has only the cropped portion of the image.

This program is not complete yet and lot of work has to be done on it . First thing which I want to do is to incorporate a graph or grid with the picture so that it becomes easier for the user to specify the crop portion otherwise it is a relatively tough task to do .

Other thing is that I want to get the path of the image file from User , but somehow Image.read function doesn’t take User input , so I will try find some other way .

I will subsequently post the newer versions of the program , as soon as I do some work on it that is worth mentioning 😀

PS:: Please don’t forget to change the path of the image , the path of thumb.write (in case statement) and path of @st in try function should match .

Please Install Rmagick and Ruby prior to run the program .

This program was run on Linux and for Windows commands can be slightly different .

Web Programming Lecture in Second Life

On 10 August 2008 , I ,Anmolanand Inshan*, got an oppertunity to attend a Live lecture on Web Programming through Ruby and Ruby on Rails in my Second Life . The lecture was delivered by Professor Arun Nighfire* (Arun Mehta) at the Kaosome hub . Apart from me other people who attended the lecture were Al Supercharge* , Freemason Magic* and Pechkin Lavochkin*. Both Al and Freemason were familiar with web programming , Al knows PHP and Freemason knows LSL i.e Linden Scripting Language . Pechkin Lavochkin is a SOMA Intern and Site Manager.

Basically , Professor Mehta told us about the beauty and simplicity of Ruby and Ruby on Rails . He also showed us his framework Skid (Special Kid) which has been designed for Special children(example : those with Cerebral Palasy , Autism etc ) to help them to communicate easily and help them to come into the mainframe of the life .

One of the things which I noticed when I was hearing to the lecture was that there was an amplification in the voice when I went towards Professor Mehta .

So , this lecture was aimed to give an Insight into Ruby , RoR and Skid , so that people can learn Ruby and RoR and also help in making new modules for Skid , if they want .

I am making a module which will help children with simple Picture editing . 🙂

The next lecture is scheduled for 17 August 2008 , 2230 hrs by IST and round about 10 am by Second life time . You can check the Second Life Events for correct timings and Venue as there can be a change .

To know more about Second Life , click here

* Names in Second Life

Presentation on Software Engineering

Today there was a workshop on “Software Engineering and it’s Principles ” in my college i.e. Acharya Narendra Dev of Delhi University . I was one of the resource persons along with my friends . I gave a presentation on “Introduction to Software Engineering and Software Engineering Models” .

The workshop was aimed to give PGDCA (Post Graduate Diploma in Computer Applications ) students basic knowledge about Software Engineering and it’s underlying Principles . It was a huge opertunity for me because I am an Undergradute and teaching students of Post Graduation something is big honour.

I started my presentation by giving them a simple definition that software engineering means applying engineering concepts to develop a software .

Next I told them the reasons that ” why we study software engineering?? ” and ” why software engineering was introduced ?? ”

The next thing on which I talked about was Software Process Models ; in this section I tried to throw light on Waterfall Model , Prototyping Model and Spial Model . Basically I told them about the methodology that is adopted in each model , Pros and Cons of respective model and lastly the areas where these can applied and best performance can be achieved out of the software engineering process .

I enjoyed teaching and it helped me too as my concepts of software engineering became more clear !!! 🙂

Setting up Internet connection on Kubuntu Hardy Heron Kde4 Remix

” How will I set up my internet connection on my Hardy Heron Kde4 Remix ?? ” , this was my biggest worry which was stopping me from installing Kubuntu Hardy Heron Kde4 remix on my notebook as I had read that setting up a network was a bit complicated on this platform.

So , I have found a good solution for getting connected to Wireless networks . To connect to a wireless network install Wifi-radar on your system .

To install wifi-radar , write on konsole sudo apt-get install wifi-radar

Once wifi-radar has been installed run it by typing on konsole sudo wifi-radar

Once you open the wifi-radar , it will check about all the available wireless networks and help you to connect with them. Just choose the netowk to connect and press the “connect ” button .

Another thing which you can try for wired networks is dhclient , it comes preinstalled in most of the linux based versions . All you have to do is , goto the konsole and type ‘sudo dhclient‘ and the rest will be handled by the software itself .

Last but not the least , I share with you a very nice tutorial on ” How to set up internet on Hardy Heron Kde4 remix ” . Click the following link below to open the blog : http://nosrednaekim.wordpress.com/2008/04/25/static-networking-in-kubuntu-804-kde4/

I hope this post will help you to solve your internet problems 😀

Installing Rmagick on Hardy Heron Kde4 Remix

I wanted to learn Rmagick and so the first step was to install Rmagick , so that I can use it in my Ruby applications and work with images too .

I found many solutions to install Rmagick on linux but after trying them out , I found out that Rmagick is not installed properly and I am not able to work with it .

Installing Rmagick can take near to 1 hour and therfore please be patient and let the system do whatever it is installing when Once the command has been given .

Installing Rmagick takes time and it is not so easy , as I found out 😀 .

So , below is the link which I followed to install Rmagick on my notebook

http://rmagick.rubyforge.org/install-linux.html

Most systems have tools specified in Step 0 and Step 1 already installed , so please check your system , so that you don’t install the preinstalled tools .

After confirming that you have the tools preinstalled , you can proceed with Step 2 and Step 3

In Step2 , I have installed ImageMagick and to know how to install ImageMagick on linux , go to http://www.imagemagick.org/script/install-source.php and follow the instructions under ” Install from

Unix Source “.

After successfully installing ImageMagick , return to http://rmagick.rubyforge.org/install-linux.html

and follow the Step 3 to install the Rmagick gem .

When you are successfully done with Rmagick installation , then write the command ‘locate rmagick‘ in the konsole and check the directory where Rmagick is installed , as this directory path can be very helpful for for future use .

I think , my post will help you in the installation of Rmagick and if this post doesn’t help you in successful installation of Rmagick then you can try other blogs and sources as well , because sometimes different distributions of linux need different steps to install cartain tools 🙂

Bluetooth in Kubuntu : How to set up and use ?

I tried setting up bluetooth in my Kubuntu Hardy Heron Kde4 Remix and after two tries I was successful in doing so , and that is why I thought that I should discuss it with you .

Setting up bluetooth is very easy , go to the Konsole / Terminal and type

sudo apt-get install kdebluetooth

it will ask you for your password and after you provide your password the installation will start .After installing some packages , you will asked the following question:

After this operation, 7037kB of additional disk space will be used.
Do you want to continue [Y/n]?

type ‘ y ‘ and press enter , the installation will complete in some time .

Now , to start bluetooth , write “kbluetooth” on the konsole / terminal and press enter .

You will see an icon of “kbluetooth”  in your panel(the one marked with a red circle and and an arrow)

Click on the image , if you are not able to view  it .

Go to the icon , right click on the icon and select  “send file

A window will open , whose image is given below  :

Searching Bluetooth Device(s) :

To search the bluetooth device(s) presently available , click the “search” button on the bottom left .

Sending file(s) to Bluetooth Device(s):

To send file(s) , choose the file(s) from the folder  and drag them into the box above the “send” button . Choose the device from the searched devices , click on the device to whom you want to send the file(s) and then click on “send” button . Your file(s) will be sent to the desired device . 🙂

Installing MySQL Server on Linux (Ubuntu and Kubuntu) for Ruby and Rails

I have installed MySQL on my Hardy Heron KDE4 remix after repeated efforts and that is why I thought that I should list the steps showing how to go about the task.

First of all open the terminal/konsole and type there “sudo apt-get install mysql-server ” and then press enter. You will be asked for your password and after providing password the installation will begin . In this you will also have to set up your MySQL password , so that your database remains secure .

Post installation type ” mysql -u root -p ” , you will be asked for your mysql password and after providing password , You should see the following :

Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 11
Server version: 5.0.51a-3ubuntu5.1 (Ubuntu)

Type ‘help;’ or ‘\h’ for help. Type ‘\c’ to clear the buffer.

mysql>

If you see the above lines ,it means you can now work on MySQL, as far as i have understood this .

Installing MySql driver :

In konsole type “apt-cache search libmysqlclient ” to find out the different library versions available.You will see text similar to the following :

libcrypt-mysql-perl – Perl module to emulate the MySQL PASSWORD() function.
ser-mysql-module – contains the MySQL database connectivity module
libmysqlclient15-dev – MySQL database development files
libmysqlclient15off – MySQL database client library

Next install the library by typing ” sudo apt-get install libmysqlclient15-dev ” on the konsole . Library will depend on the version of MySQL you are using , you can select your library from the output which comes after writing  “apt-cache search libmysqlclient” and then pressing tab two times .

Install MySQL driver with the Ruby ” gem install ” command . Type ” sudo gem install mysql ” on the konsole , here you will get various options choose “mysql-2.7” or any other latest version and install it . On successful install you will get a message stating that mysql-2.7 has been Successfully installed .

Your Installation of mysql is complete .

If you are new to MySQL , like me , you can install MySQL Query Browser and MySQL Administrator from the Adept Manager or Synaptic both of which are default package managers for kubuntu and ubuntu respectively. I have installed Query Browser and Administrator from Adept Manager as I am a Kubuntu user .

Volume Control in Hardy Heron KDE4 Remix

I was listening to a song on my newly installed Hardy Heron Kde4 remix , I wanted to increase the volume but I was not able to find the Volume Control icon in my Kde 4 panel . So i have found a solution to this problem 😀 .

The solution to this problem is quite easy , go to Konsole and write Kmix and then press Enter .

On pressing Enter the icon (speaker) will appear in the panel (second from right in the picture below)

Now you can control volume of your system by right clicking on the icon in the panel . If volume is still low , you can go to the icon in the panel , right click on the icon and then choose “mixer” option below and increase the “front volume” to full , to get the maximum sound output. 🙂