Tech Gossipz

Executing external files from a Netbeans plugin

2011-05-08T00:34:00.000+05:30

As developers we are familiar with lot of IDEs among them Netbeans is one of the most popular IDE in the world. it is an open source platform and have a pluggable architecture where developers can extend the features of the IDE by adding plugins. the purpose of this article is not to tell how to write Netbeans plugin this will tell you how to call an external batch file exe or if you use Linux how to call a linux command from a plugin.

first create a Netbeans Modules project

then right click on the project and select new and Action. that will create an Action for you. then right click on the project and select properties and select Libraries

then choose the Add option. tick the Show Non-API Modules option

press ok..
add the folliwing import statements.

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.IOException;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
import org.netbeans.api.extexecution.ExecutionDescriptor;
import org.netbeans.api.extexecution.ExecutionService;

and add this method into the source code :

    public Integer execute() throws InterruptedException, ExecutionException {
        Callable processCallable = new Callable() {

            public Process call() throws IOException {
                return new ProcessBuilder("/bin/ls").start();
            }
        };

        ExecutionDescriptor descriptor = new ExecutionDescriptor().frontWindow(true).controllable(true);

        ExecutionService service = ExecutionService.newService(processCallable,
                descriptor, "ls command");

        Future task = service.run();
        return task.get();
    }

and then call this execute() method from the actionPerformed() method in the Action class.
here i am running ls command in linux but you can use any other external program by giving its path.

Learn Objective-C on Windows

2011-01-21T19:50:00.003+05:30

In todays world there are loads of Operating systems exists, among them Mac OS easily one of the most eye candy and lovely OS most people want to use but for some reasons most people doesn’t own a Mac. As programmers we all love to program for iPhone I don’t know why but people love to. so how can they develop applications for iPhones basically in Objective-C without an Apple Mac. the simple answer is Hackintosh but there are lot of other alternatives as well I will explain few of them in a later post but today I am going to explain how to learn Objective-C on a Windows machine. recently I installed Mac OS X on my machine but still I use Windows and Linux most of the time. So if there is way for you to at least learn objective-C on Windows that would be really helpful.
in order to compile Objective-C on Windows we need to install following package which is called GNUstep if you are a Windows user go to this link and download and install at least the first three packages.
then go to start –> all programs –> GNUstep –> shell
it is a Unix like terminal where you can issue some unix terminal commands. Then open your favorite text editor in my case I am using Vim by just typing vim and enter on the shell I opened up earlier but you can use Notepad++ or any other appropriate text editor.

#import <stdio.h>

int main( int argc, const char *argv[] ) {
printf( "hello world\n" );
return 0;
}

and save it as hello.m remember to save it in the home folder as GNUstep installed if you’d have used vim there won’t be any problem but if you used any other text editor don’t forget to save it in there in my case the path is : C:\GNUstep\home\Keshan so yours might look similar to this. Then in the terminal type :

gcc `gnustep-config –objc-flags` –L /GNUstep/System/Library/Libraries hello.m –lgnustep-base –lobjc

and then to run simply type ./a

so this is a basic hello world program but Objective-C is bit different this is simply a C like program actually Objective-C is an extended version of C you can find loads of tutorial about Objective-C and try them out on Windows with this cool package. here is the same code run on Mac OS X

Assembly Debugger

2010-12-27T17:54:00.003+05:30

For quite a some time I fell in love with Assembly programming language and now it is my favorite language. it is powerful easy and with assembly I get to know lot about computer architecture and the internal work very well. I am currently doing a project as a hobby implementing thumb and fore finger interface algorithm in assembly and writing a multi touch mouse driver in assembly but last few weeks and until the end of January I don’t have much time to deal with my loving language because of some hectic web projects and university exams.
so today for those who like assembly I will explain how to use assembly debugger if you are a newbie you will need this. this is one of the things I learnt in order to get familiar with assembly.in fact you already know the command prompt. so with windows you can use this debug tool debug.exe which installed with windows without doing any downloads or installings. open a windows command prompt and type debug. then type a100 and press enter

here “a”(assemble) is a command and 141A:0100 is the memory location that we are going to enter our code in fact 141A is the segment and 0100 is the memory location inside the segment. you may get a different segment.. now insert this code :

mov ax,0001
mov bx,0010 
add ax,bx 
int 20

after entering the above code press enter twice to tell the debugger that you have entered the code.this code is simply add two numbers. if you want to see what are the values inside all the registries when executing each instruction use “t” command. as you can see here after the execution the accumulator (AX) has 0011 value. in order to see the value of a given registry use “r” command with the register.

to run a program use “g” command and to go out from debugger use “q” command.
there are some more commands associated with debugger but I think this is enough to get started for any problem don’t hesitate to comment below..
cheers !!
Kesh….

Run Android Froyo in your VirtualBox

2010-12-22T22:50:00.000+05:30

Sometime ago i wrote how to use Android with VirtualBox. Now it seems lot of people wants to experience Android Froyo on VirtualBox. in this article i will show how to use Android-x86 project and run Android Froyo.

first download the Android Froyo iso or you can visit the download page and select an iso or img file yourself. Now you can use this CD image in two ways.
1. with VirtualBox
2. as a bootable USB
first i will explain how to use it with VirtualBox.
if you don't have VirtualBox installed download and install it. then run it and create a new instance.

likewise clicking next will create a new instance.

then double click on Android-x86 and start the instance.

and then click on the place where i have circled

next thing add the downloaded ISO and attach it

right. after finishing it you can use Android !!

select Live CD or if you want to install it to your virtual hard disk select installation.

if you experience that you can't use your mouse inside Android(use mouse and there are keyboard instructions as well like escape for going on step back) go to Machine and Disable Mouse Integration. or press Host(normally the right control key + I) once your mouse is captured press right control to come back to host operating system

it is up to you to explore Android with VirtualBox

as i told earlier the second way is to make a bootable USB with this ISO to do it first download UnetBootin and run it.

Select Diskimage and browse and open the iso file then check whether you have an USB in the given drive and click ok it will take sometime and create a bootable USB. so you can boot your computer with that USB and use Android as a Live CD or install it to hard disk....

Cheers !!
Kesh

An introduction to Assembly language

2010-12-16T23:12:00.000+05:30

These days i don't have much time to get involve in C/C++, assembly and my loving researches on Computer vision things because i have to complete projects and assignments and also prepare for the last examination of my bachelors degree. however today i did some experiments with assembly by writing a simple media player and a email sending(kind of a keylogger though ;) ) application and i found a new IDE(new for me but it is not a new IDE :) ) for assembly. so i will explain how to configure that IDE first. remember i am not going to start a tutorial series in assembly but i hope to tell how to write some few simple applications in assembly.(not today :) because i have to complete my part of the group project)

first of all download this zip file and unzip it into a desired location. then you have to download MASM32 because it's not coming with WinAsm.
install MASM32 (for an example to C:\masm32)
go to unzipped WinAsm folder double click and run WinAsm.exe
before writing any application for the first time you have to set some variables
go to tools -> Options you will get something like this

6. then select Files & Path tab

7. edit the path variables as you installed then and then press ok...

right now you are done. so if you have some sort of a knowledge in assembly you can start coding. or i will give you a simple assembly code to test the IDE

go to file -> New project and create a standard EXE project. then simply copy and paste the below code :

.386
.model flat,stdcall
option casemap:none
include \masm32\include\windows.inc
include \masm32\include\kernel32.inc
includelib \masm32\lib\kernel32.lib
include \masm32\include\user32.inc
includelib \masm32\lib\user32.lib

.data
MsgBoxCaption    db "Keshan's Tech Gossipz",0
MsgBoxText     db "I love Win32 Assembly !",0

.code
start:
invoke MessageBox, NULL, addr MsgBoxText, addr MsgBoxCaption, MB_OK
invoke ExitProcess, NULL
end start

now go to Make -> Go All. this program will show a dialog box !!

cheers !

Kesh

The ugly truth of web security

2010-12-15T00:05:00.000+05:30

Last few weeks as we all aware there were lot of interesting things happened in the cyber world. Wikileaks, 4chans, Gnosis, LOIC, DDoS are some of the keywords today. couple of days ago a reputed web media company called Gawker media was hacked by a gang known as Gnosis. they didn't stop only by hacking the site but they dump 1.3 million data from Gawker database which includes username passwords the future changes of Gawker site source codes and upload it as a torrent file (i however found that torrent file and downloaded the content :D ) so, if you are using a account to comment on sites like Gizmodo, lifehacker then you account is most probably been hacked ! and the worst case is if you are using the same password for every site in the web then you are in a huge trouble.

Things i noticed in hacked files

when i go through the downloaded files i noticed there are thousands of people using "password", "password1" without quotations as their password there were few common passwords like "password", "qwerty", "qwerty12". not only the normal Gawker users the people who are in administrative positions had very weak passwords. so, as users people should be more careful when choosing a correct password.

Things web developers should learn

here the hackers exploited a vulnerability in the CMS and took control of everything. there were lot of things that Gawker media web development team has done wrong.
they have saved the password not the salted hash !!!! you must NOT do it. instead you should save the salted hash.
why didn't they use a mechanism like openID or Facebook connect. then the attackers cannot get the users passwords.
and the other main thing as the attackers mentioned in a readme file :

Gawker uses a really outdated hashing algorithm known as DES (Data Encryption Standard) Because DES has a maximum of 8chars using a password like "abcdefgh1234" only the first 8 characters "abcdefgh" are encrypted and stored in the database. If your password is longer than 8 characters you only need to enter the first 8 characters to log in!

YA DONT SAY!! :D?

Because of this we were only able to recover the first 8 characters of someones password! If the password is 8 characters long there's a good chance that it migt be longer than 8 characters! But still, there's 1000's of people using 1 - 8 character passwords for us to have some fun with!

so when designing a web site beware of algorithms you are using to hash passwords if it's like in this case the outdated encryption algorithm make hell a lot of trouble..

after this attack there were thousands of articles posted on new security models and i will discuss some of them later, but as for final words i think as users we have the responsibility to keep our privacy as Google CEO once said if you want your privacy don't post anything on the web. when choosing a password security question users should think not twice, thrice.....

cheers !
Kesh

How to reduce the dependency hell in Linux

2010-11-14T20:26:00.000+05:30

This is my first post after 2 months !! anyway today i am going to give a special tip for Linux users. if you are a linux user you must have faced with dependency hell. recently i stumble upon to this project on github so, here i will explain how to use that awesome project to reduce the dependency hell in other words you can run a program which run perfectly on your machine in another machine without think about any dependencies or setting up the environment.

click here and download this file from github, if the link doesn't work or if you prefer to download the source code and build yourself follow this instructions

git clone git://github.com/pgbovine/CDE.git
cd CDE
make

if you have downloaded the compiled code follow these instructions

mv cde_2010-11-13_32bit cde
chmod g+x cde

NOTE : cde_2010-11-13_32bit should be replaced with your downloaded filename.

done. now what?
ok let's use this great little program. assuming that the cde file is in your present working directory you can type this in the terminal.

echo "hello" >> test.txt
./cde vim test.txt

here i created a text file and write hello in it and used vim to open the text file you can use any program not only vim (e.g cat, gedit, vi). you will see no difference it opens the vim editor with hello in it. but if you just happen to type a ls you will see a directory which you didn't create ! in that directory it holds all the dependencies need to run the program.

now you can zip that cde-package directory and unzip in any machine which has the same operating system and open your text file with vim. so let's say the second machine doesn't have vim but still you can run vim text.txt !!! using cde you can run not only vim but any program you just need to run the program with cde

./cde program_name

in order to run the program in the second machine you have to follow these instructions

cd cde-root
ls

what can you see ?

it is almost like your root folder ! now go to the directory where you had that text file in my case i had it in /home/keshan/Downloads/Test/ in my original machine so, in your second machine go to the same directory(when you type home omit /) and now type ./vim.cde test.txt

cd home/keshan/Downloads/Test
./vim.cde test.txt

try this out with any program....

cheers !

-Kesh,

What will be the next web stack ?

2010-09-10T14:29:00.000+05:30

Technology is something which improves rapidly. things we thought decade ago were impossible have become realistic today. Today The Internet plays a major role in day to day life. From one static web page has now become much more agile dynamic web sites and even the rich internet applications(RIA) has made The Internet a more exciting place. now with the emergence of concepts like cloud computing businesses and technology moves into a different direction.

What is a web stack ?
A web stack is simply a stack of software, mainly comprised of open source software, will contain an operating system, Web server, database server, and programming language. One of the most most well-known web stacks is LAMP.

Apache as a web server has been using more than a decade and served for many big web applications but can it do the same thing in next generation ?
with cloud computing it needs a more agile light weight and secure web server like lighttpd. lighttpd is an open source web server which is rapidly redefining efficiency of a webserver; as it is designed and optimized for high performance environments. With a small memory footprint compared to other web-servers, effective management of the cpu-load, and advanced feature set (FastCGI, SCGI, Auth, Output-Compression, URL-Rewriting and many more) lighttpd is the perfect solution for every server that is suffering load problems. big web solutions like YouTube, Wikipedia are already using lighttpd to serve their clients.
unlike in normal web applications Cloud computing solutions need a distributed file system like GoogleFS which was developed by Google and used by Google. So, Apache Hadoop with MogileFS can be used to fulfill that requirement. Apache Hadoop is a software framework that supports data-intensive distributed applications under a free license. It enables applications to work with thousands of nodes and petabytes of data. Hadoop was inspired by Google's MapReduce and Google File System (GFS) papers.Hadoop is a top-level Apache project being built and used by a global community of contributors, using the Java programming language. Yahoo! has been the largest contributor to the project, and uses Hadoop extensively across its businesses.

So, with these new concepts and new technologies we could see a more reliable, secure, speed and agile world wide web.

Cheers !
Kesh,

How to catch your invisible friends on GTalk

2010-08-29T20:43:00.001+05:30

If you have a Google account then you might have experienced Google chat which is integrated with GMail and it can also accessed via XMPP. if you have used it then you may know that so many people don't like to go online so they make themselves invisible. today in this post i am going to explain a simple way to find out who are the invisible buddies.
in this post i have used python and python-xmpp library and i have tested this on Linux but i suppose this will work on Windows as well.
since i did this on Linux(Ubuntu) i am writing the steps for Debian based operating systems which normally comes with python. type this in you terminal

sudo apt-get install python-xmpp python-dnspython

enter your super user password and wait till it installed. then open your favorite text editor in this case i am using gedit. copy and paste this code :

import xmpp

FROM_GMAIL_ID = "kesh.jboy@gmail.com"
GMAIL_PASS = ":Pthisisnotmyrealpassword:P"
GTALK_SERVER = "gmail.com"

jid=xmpp.protocol.JID(FROM_GMAIL_ID)
C=xmpp.Client(jid.getDomain(),debug=[])

if not C.connect((GTALK_SERVER,5222)):
    raise IOError('Can not connect to server.')
if not C.auth(jid.getNode(),GMAIL_PASS):
    raise IOError('Authentication error.')

C.sendInitPresence(requestRoster=1)

def myPresenceHandler(con, event):
   if event.getType() == 'unavailable':
     print event.getFrom().getStripped()

C.RegisterHandler('presence', myPresenceHandler)
while C.Process(1):
  pass

right !!! save this file as mygtalk.py and simply type

python mygtalk.py

in terminal...... wow you can see all your invisible buddies just give them a wink... have fun..

Cheers !
Kesh,

Creating a GTalk client with C# - Part 2

2010-08-29T15:45:00.007+05:30

I think you have already read my previous blog post : Creating a GTalk client with C# - Part 1. So now you have created a login form and only authenticated people can log into the client. in that post when a user authenticated what i did was just disposed the current window so in this post i will create another form and show it instead of disposing the login form. So create another form with VS where you should have a list to load you buddy list, another list to show your chats, a text box to type your chats and a send button.(This is my basic design but it is up to you to design whatever way you like :) )

alright everything is set to do the codings.... go to source and initialize a XmppClientConnection object but this object should be the same object as we created in the previous form. so what i did was made that earlier object static(in form 1) and also create a static method called getXmpp() in form1.cs

static XmppClientConnection xmppCon = new XmppClientConnection();

        public static XmppClientConnection getXmpp()
        {
            return xmppCon;
        }

you may find a better way than this.

then in form2 add this line.

XmppClientConnection xmppCon = Form1.getXmpp();

now you have to subscribe to events so create a new method called init()

        private void Init()
        {
            chatList.Items.Clear();
            xmppCon.OnRosterStart += new ObjectHandler(OnRosterStart);
            xmppCon.OnRosterEnd += new ObjectHandler(OnRosterEnd);
            xmppCon.OnRosterItem += new XmppClientConnection.RosterHandler(OnRosterItem);
            xmppCon.OnPresence += new agsXMPP.protocol.client.PresenceHandler(OnPresence);
            xmppCon.OnError += new ErrorHandler(OnError);
            xmppCon.OnClose += new ObjectHandler(OnClose);
            xmppCon.OnMessage += new agsXMPP.protocol.client.MessageHandler(OnMessage);
        }

here chatList is the ListBox which we create to show the chats and Roster means the buddies. now invoke this init method in the constructor after InitializeComponent();

        public Form2()
        {
            InitializeComponent();
            Init();
        }

now simply create the methods to handle the events which were registered.

       void OnMessage(object sender, agsXMPP.protocol.client.Message msg)
        {
            if (msg.Body == null)
                return;

            if (InvokeRequired)
            {
                BeginInvoke(new agsXMPP.protocol.client.MessageHandler(OnMessage), new object[] { sender, msg });
                return;
            }

            chatList.Items.Add(String.Format("{0} type:{1}", msg.From.Bare, msg.Type.ToString()));
            chatList.Items.Add(msg.Body);
            chatList.SelectedIndex = chatList.Items.Count - 1;          
        }

        void OnClose(object sender)
        {
            if (InvokeRequired)
            {
                BeginInvoke(new ObjectHandler(OnClose), new object[] { sender });
                return;
            };
        }

        void OnError(object sender, Exception ex)
        {
            if (InvokeRequired)
            {
                BeginInvoke(new ErrorHandler(OnError), new object[] { sender, ex });
                return;
            }
            chatList.Items.Add("Error");
            chatList.SelectedIndex = chatList.Items.Count - 1;
        }

       void OnPresence(object sender, agsXMPP.protocol.client.Presence pres)
        {
            if (InvokeRequired)
            {
                BeginInvoke(new agsXMPP.protocol.client.PresenceHandler(OnPresence), new object[] { sender, pres });
                return;
            }
            chatList.Items.Add(String.Format("Received Presence from:{0} show:{1} status:{2}", pres.From.ToString(), pres.Show.ToString(), pres.Status));
            chatList.SelectedIndex = chatList.Items.Count - 1;
        }

        void OnRosterItem(object sender, agsXMPP.protocol.iq.roster.RosterItem item)
        {
            if (InvokeRequired)
            {
                BeginInvoke(new XmppClientConnection.RosterHandler(OnRosterItem), new object[] { sender, item });
                return;
            }
            buddyList.Items.Add(String.Format("{0}", item.Jid.Bare));
            buddyList.SelectedIndex = chatList.Items.Count - 1;
        }

        void OnRosterEnd(object sender)
        {
            if (InvokeRequired)
            {
                BeginInvoke(new ObjectHandler(OnRosterEnd), new object[] { sender });
                return;
            }
            xmppCon.SendMyPresence();
        }

        void OnRosterStart(object sender)
        {
            if (InvokeRequired)
            {
                BeginInvoke(new ObjectHandler(OnRosterStart), new object[] { sender });
                return;
            }
        }

this is simply the code you can customize in whatever way you like. :) so now the last thing in form1 we only dispose the form so now let's replace that line with this :

new Form2().Show();

ok now run it. select a buddy from buddylist and chat... have fun... if you have any problem regarding the code feel free to comment below or send me an email to : kesh.jboy@gmail.com

cheers !
Kesh,

Creating a GTalk client with C# - Part 1

2010-08-27T14:35:00.000+05:30

Today i am going to create a GTalk client with C# on Visual Studio 2008. So without talking much let's start developing :). here i am using agsXMPP library. so first you need to download and install agsXMPP SDK. open Visual Studio and create a new project.

first of all we need to create some kind of a login form so only authenticated person can log in. design a login form with VS.

ok design has been done ! now go to the source of the form and initialize a XmppClientConnection object

XmppClientConnection xmppCon = new XmppClientConnection();

in this first part i am only going to implement the authentication part and sending and receiving chats will be covered in the second part and i hope to add some new and cool speech technologies in third part :).

so for authentication and login we have to declare handlers in the constructor

xmppCon.OnLogin += new ObjectHandler(OnLogin);
xmppCon.OnAuthError += new XmppElementHandler(OnAuthError);
xmppCon.OnError += new ErrorHandler(OnError);

so, this means we should have three methods OnLogin, OnAuthError and OnError

void OnError(object sender, Exception ex)
        {
            if (InvokeRequired)
            {
                BeginInvoke(new ErrorHandler(OnError), new object[] { sender, ex });
                return;
            }
            MessageBox.Show("Error occurred");
        }

this method invokes when an error occurred so, you can handle it anyway you like. since windows forms are not thread safe here and in next two methods also i have to invoke the BeginInvoke method.

void OnAuthError(object sender, agsXMPP.Xml.Dom.Element e)

        {
            if (InvokeRequired)
            {
                BeginInvoke(new XmppElementHandler(OnAuthError), new object[] { sender, e });
                return;
            }
            MessageBox.Show("Your username or password in invalid");
        }

void OnLogin(object sender)
        {
            if (InvokeRequired)
            {
                BeginInvoke(new ObjectHandler(OnLogin), new object[] { sender });
                return;
            }
            this.Dispose();           
        }

here in OnLogin method i did nothing but disposing the current form but in my next post i will explain how to create another form and load our buddy list and send receive chats with them.
so are we done with this? :) this code won't compile because we didn't add any reference to agsXMPP library so right click on References and browse to the location where you installed add reference to agsxmpp.dll then add

using agsXMPP;

this will compile and run but nothing will happen because we still didn't say anything to do when we click the login button so now it is time to do it. double click on the button so VS automatically generate the method.

            Jid jidUser = new Jid(username.Text);

            xmppCon.Username = jidUser.User;
            xmppCon.Server = jidUser.Server;
            xmppCon.Password = password.Text;
            xmppCon.AutoResolveConnectServer = true;

            xmppCon.Open();

now this is it. done! the form will be disposed if you are successfully logged in my next part i will explain how to chat not only disposing the current form.. if you have any question feel free to comment below.

Cheers !
Kesh,

Google Goggles with Facebook ?

2010-08-16T22:56:00.002+05:30

I just came up with a crazy idea just a couple of months ago when i got to know about Google goggles. Google as always produce some innovative products Google Goggles is one of them. just watch this video if you don't know about Google Goggles

So the thing this great application lacks is the lack of data in the database. so i just came up with an idea of integrating Facebook with Goggles i know it is a crazy and fancy idea because it violates all the privacy laws. :) but thing i just want to say is that something like facebook which has over 500 million users and it has a huge collection of photos of so many people in different angels with different positions and most importantly they are manually tagged so using these type of a database it is much easy to implement Goggles for people search there are so many technical problems (frankly speaking i can't do it but facebook and Google can.. :)) as well as legal issues although we can use the photos which were made public (then there won't be any violation of privacy laws i guess) anyway this is just a crazy idea...

cheers !
-Kesh

GoogleCL- Google services via Command line

2010-06-19T20:13:00.000+05:30

People, who are using *nix heavily, have used to a terminal very much sometimes they addict to the terminal. so, for the people who wants to use Google services via command line there were no proper and easy way, but finally now we have a way to do it. The project is called GoogleCL and it uses Google Data API and still facing some constrain due to the limited support for some google services by the GData API. These Google services includes Blogger, Youtube, Google Docs, Piccasa and Calendar. you need to have Python 2.5 or higher installed in your system because this project uses Google Data API Python client library. After installing Python and GoogleCL the life is much easier for the people who have addicted to the *nix Terminal.

here are some things you can do with GoogleCL but these not the only things you can do with GoogleCL and it is still been developed as an open source project.

Blogger

google blogger post --tags "Google, GoogleCL" --title "Test Post" "I'm posting via terminal"
google blogger post blogpost.txt
google blogger list title,url-site # List posts
google blogger delete --title "Test Post"

Calendar

google calendar add "write a blog post at 7pm" # add event to calendar
google calendar today # List events for today only.
google calendar list --date 2010-06-01,2010-06-19 # List events.
google calendar delete --title "write a blog post at 7pm" # Delete an event.

Contacts

google contacts add "Keshan Sodimana, kesh.jboy@gmail.com"
google contacts list name,email --title "Keshan Sodimana"
google contacts delete --title "Keshan Sodimana"

use GoogleCL be familiar with it and have fun....

Cheers !!

Kesh,

Google TV and the introduction of Android 2.2

2010-05-21T14:22:00.000+05:30

As everyone expected Google has finally introduced their latest Google TV at the Google IO conference second day which was meant to be the Android day.

according to Vincent Dureu, in charge of Google TV this is why Google TV is needed :

Even two years ago you would have said that telephones are mostly for making calls, maybe for email and texting. Today, we know that phones can actually do a whole lot more. In the same way, people say that TV is just for watching TV. But, like the phone can be used for more than making calls, we believe that TV can be used for more than just video. Also, there’s not enough shelf space for the stuff on TV; not even with online channel guides and your PVR access and your racks full of disks. The shelf space should be as big as the web.

Google TV, which will come with the collaboration with Sony, intel and Google is powered by Google Chrome initially so developers can build web apps as well as Android apps to run on Google TV platform but for now the SDK for mobile apps haven't been released.

with the introduction of Google TV Google also introduced their new mobile OS Android 2.2(FroYo) and which has a lot of new features over its predecessor Android 2.1(Eclair).

the new version is pretty much fast and it has a new JIT (Just-In-Time) compiler to boost the performances. here are the pros and cons about the newly introduced FroYo

cheers,
Kesh.

Google Font API

2010-05-20T18:06:00.000+05:30

Google as always came up with a new API called Google Font API this time. it is a start up for web fonts and the API is totally open source so, anyone can even download the fonts and alter them as they wish yet that API supports a few fonts because the API was introduced a little while ago so, hopefully it will expand and make something good for the world wide web. here is the Google font directory where you can find all the fonts. here in this document google has documented very clearly for beginners to how to use their new API.
These fonts works really well with HTML 5 and CSS 3 so, that will be great when it comes to the future of world wide web because it supports the rotations, shadows etc. in HTML 5.
The other big news is Smashing magazine is already relaunched their site with Google's newly launched web font API. so, the trend will be this let's hope for a bright future for world wide web.

cheers,
Kesh.

Openness, Flash and Apple

2010-05-20T12:59:00.000+05:30

It's been a while since Apple Adobe fight has begun. it's because Apple CEO, Steve Jobs. he said prefers HTML5, the new web standard to Adobe's Flash so, Apple hasn't given any support for Flash in their products. however Adobe released a HTML 5 support plugin for it's new Dreamviwer CS 5 during the Google I/O 2010 in yesterday 19th of May.if HTML 5 is the replacement for flash as Jobs believe why Adobe is supporting HTML 5? and the other thing is being one of the most closed systems in the world why Apple is supporting a open standard like HTML 5 ?
may be that is because Apple wants be the only company which sells proprietary software but on the other hand Microsoft is silently replacing Flash with their own Silverlight which is more a likely a replacement for Flash than HTML 5. though these two closed source software giants reject Flash the search engine giant, Google is going to introduce their new Android OS with the Flash support in the Google IO 10, and that is why Android is getting more market shares than Apple iPhone currently because still Flash has its authority on web content like animations and video basically media so, people need to fulfill their own needs so yet Flash player is the only solution till HTML 5 grow up we have to content with Flash and HTML 5 will grow up with Adobe's great tools, those tools are the basic things which made Flash a popular technology.

Gnerate RSS for your site in Rails

2010-03-18T19:02:00.000+05:30

With the rapid development in world wide web it is obvious that we cannot go to every site we like in daily basis to check for its updates to eliminate that problem we have something called rss in web 2.0. as a developer it is a cool idea to generate rss for your site then your site readers can keep in touch with your web site or blog.

here i am going to explain how you could easily do it with Rails.

first i assume you have a rails project and have a controller called post(you can have whatever name but this example is based on a controller called posts) go to post_controller.rb in your Controllers directory and change the index method

 respond_to do |format|
      format.html
      format.xml  { render :xml => @posts }
      format.rss  { render :layout => false }
    end
  end

and then go to Views and add a file called index.rss.builder to posts view directory and the below content to that file(remember in RoR convention is over configuration so, be careful about naming conventions)

xml.instruct! :xml, :version => "1.0"
xml.rss :version => "2.0" do
  xml.channel do
    xml.title "posts"
    xml.description "Lots of posts"
    xml.link formatted_posts_url(:rss)

    for post in @posts
      xml.item do
        xml.title post.title
        xml.description post.body
        xml.pubDate post.created_at.to_s(:rfc822)
        xml.link formatted_post_url(post, :rss)
        xml.guid formatted_post_url(post, :rss)
      end
    end
  end
end

here we go it is done to view this you can start the server and go to http://localhost:3000/posts.rss

but it is better to add a link to the rss feeds to do it go to index.html.erb in Views, posts view directory and add the following line where you want to see the lnk

<%= link_to "RSS", formatted_posts_url(:rss) %>

if you want to clarify anything do not hesitate to comment below
have fun !!

Kesh,

PaperClip with Ruby on Rails

2010-03-15T12:53:00.002+05:30

When you are developing a web applications sometimes you need to have pictures uploaded and attached(embedded) to your pages. In Ruby on Rails it is really easy task to handle those kind of things you just need to to use the plugin. PaperClip appropriately.

before begin here, i assume you know how to create a rails project and do the basic stuff if not please read this before continue

imagine you have a rails project with a user profile and what we going to do is add an avatar to this profile. first you need to install PaperClip plugin

script/plugin install git://github.com/thoughtbot/paperclip.git

then we need to run the paperclip generator to add some columns to the migration table

script/generate paperclip user photo

here user is the model that you want the attachements to be added and photo is the name you want that attachment to be called. then run the migrations

rake db:migrate

then we need to add a line to user model which is in models directory

class User <  ActiveRecord::Base
has_attached_file : photo
end

photo is the name we used earlier in migrations. then we need to do a simple alteration in view.
first,

<%form_for @user , :html => { :multipart => true} do |f|%>

if you don't add set multipart to true it will not accept file attachments. then add a field for file uploads

<%= f.file_field :photo%>

right now you are done but if you execute this you won't see the picture in order to it you need to edit your show action template in user view

<%= image_tag @user.photo.url %>

this will render the image into the page.

it is done. hope you can follow this instructions if you have any problem please comment below

Kesh,

Linux for entertainment : Element OS

2010-02-21T23:19:00.000+05:30

(picture- http://www.elementmypc.com/)

Element OS is a new Debian based new operating system mainly focused on Home Theater systems and Media center personal computers and aims to integrate GTK applications into a ten-foot user interface with XFCE environment.
this OS is not limited to a typical home theater system this can be integrated with Boxee , Hulu etc.. and since this has been developed on Debian literally it has all the other features, packages and softwares which supports debian operating system.

for more screenshots and more information visit Element OS web site

for installation : download the CD image from here it is 638MB and it is recommended to have a computer:
processor 1.6GHZ
RAM 1GB+
free Hard disk space 20GB
your PC can be connected to HDTV

entertain yourself with Linux... have a nice time..

Kesh,

How to parse HTML using DOM with PHP

2010-02-21T01:52:00.005+05:30

If you are a PHP programmer who is comfortable with XML you already know how to parse a XML file in PHP since HTML is merely a subset of XML the same technique can be applied to HTML parsing as well let me illustrate it :

for an example let's assume we have table of data about whether forcast but they don't provide RSS feeds so, in order to extract the data and view we need to parse its HTML page somehow.

assume this is the html code snippet:

 <html>
       <body>
             <table>
                     <tr>
                          <td>Colombo</td> 
                          <td>30</td>
                          <td>Sunny</td> 
                     </tr>
                     <tr>
                          <td>Hambantota</td> 
                          <td>33</td>
                          <td>Sunny</td> 
                     </tr>

             </table>    
       </body>
 </html>

save it as data.html now we are going to parse this data.html with PHP,

<?php
  // new dom object
  $dom = new DOMDocument();

  //load the html
  $html = $dom->loadHTMLFile(data.html);

  //discard white space 
  $dom->preserveWhiteSpace = false; 

  //the table by its tag name
  $tables = $dom->getElementsByTagName('table'); 

  //get all rows from the table
  $rows = $tables->item(0)->getElementsByTagName('tr'); 

  // loop over the table rows
  foreach ($rows as $row) 
  { 
   // get each column by tag name
      $cols = $row->getElementsByTagName('td'); 
   // echo the values  
      echo $cols->item(0)->nodeValue.'<br />'; 
      echo $cols->item(1)->nodeValue.'<br />'; 
      echo $cols->item(2)->nodeValue;
    } 

?>

now we have done with it put the php code into your server along with the html file and run.....

Kesh,

Open Source MeeGo for mobile devices

2010-02-20T02:11:00.001+05:30

Mobile OSs are a hot topic today because Google introduce Nexus One with Android Apple came up with iPad and Windows is coming with Windows 7 mobile so, Intel and Nokia has also came up with a new operating system based on Linux.

MeeGo is a combination of Intel's Moblin and Nokia's Maemo projects. creating a one single platform for next generation devices like tablets, netbooks etc..the interesting point about MeeGo is that it is a product of world largest chipset manufacturer and worl largest handset manufacturer.both companies are working together to create a new Atom based SoC(System on Chip) called PenWell for netbooks and Mobile phones.

Why MeeGO so powerful?

it has been built for powerful next generation devices from the ground level.MeeGo has a powerful computation which take advantage of its new form factors.

it has a cross platform support which means MeeGo is multi-architecture and can be used in a broad range of devices from TV to your tablet PC to your mobile phone.

MeeGo is open with Linux kernel and open model it is really strong.

Developers can target various platform like windows, Mac, Linux, Symbian etc.. with Qt and MeeGo because of its application portability.

With the open source appearance in mobile OS war it will be a great competition between Google, Apple, Microsoft and Intel-Nokia.

Kesh,

Experience Android on VirtualBox

2010-02-15T15:55:00.002+05:30

UPDATE : Android Froyo with VirtualBox

Android, which is one of the most revolutionized mobile OS introduced by Google has come long way since its first introduction. recently Google released Nexus One phone which was said to be good by Linus too. so, everyone would like to experience Google Android although you have no Android supported phone. here's a way with your favorite VirtualBox.

Step 1 :

Download the 2 latest CD images.

image 1

image 2

Step 2 :

if you are on windows use PowerISO or something to combine these two CD images

if you are on Linux change directory to the directory where you put your image files and simply type the following:

cat liveandroidv0.3.iso.001 liveandroidv0.3.iso.002 > liveandroidv0.3.iso

(make sure that you have typed the correct version number as mentioned in the image file)

Step 3 :

Start VirtualBox and create a new virtual machine : select Operating System as Linux 2.6 and give 300+ MB for Base memory and you don't need to create a virtual hard disk.

Step 4 :

Start the newly created Virtual machine : and in the wizard choose CD/DVD-ROM Device as Media type and Image file as the source. simply select the location of your CD image to that place.

That is it.... now you will boot into Android OS have fun........

Controls :

Arrows - Navigation

Enter - confirm

Escape - back

windows key - home

Kesh,

Future of WWW

2010-02-15T13:12:00.002+05:30

With the latest controversial statement of Steve Jobs about Adobe turned up the heat of the debate about the future web. HTML 5 is the latest rival of Flash but still Flash has high number of market shares relative to the latest HTML 5 but recently Youtube, the biggest site for video sharing, has also introduced a new HTML 5 type of a video player instead of Flash player it is still on beta so, we don't know much about it's good and bad.

What is HTML 5?

HTML 5 is the latest version of HTML and its main objective is to reduce the use of proprietary RIA(Rich Internet Application) plugins. with the new API HTML 5 provides the support for audio and video embedding which it lacks for years. it has introduced new elements as well as functionalities like drag and drop. so, people believe it will revolutionized the future web, with Open web.

On the other hand Flash which has established for years is the main counterpart of HTML 5 up to now majority of RIA needs Flash player to run.

Anyway, HTML 5 will be a great alternative for Flash and it will help to reduce security risks which we faced with Flash like clickjacking(though Adobe has corrected this issue there are some security risks still to be solved) let's hope for a better and open web..

Kesh,

The Master Minds

2010-02-04T14:50:00.002+05:30

Internet has become a main part of lives it plays a major role in todays world. it seems that without internet we can't live this can be an exaggeration but Internet has evolved gradually in past few decades. in day to day life in cyberspace we use Google, Facebook, Twitter, Digg, Blogger, Wordpress etc..but how many times do we think about the masterminds behind those unbelievable products. here's a brief summary of few of those masterminds :

Facebook : Mark Zukerburg

Becoming the world youngest Billionaire in January 2010 Zukerburg celebrates the 6th anniversary of Facebook today (Facebook was founded in 4th February 2004). He was one of the most influenced people in 2008 but still he is 25 years old, born in May 14, 1984. the idea Facebook came to him when he was in Harvard the idea was to publish an annual student directory with headshot photos of all students from then onwards it grows and grows now it has more than 350 millions of registered users.!!

Google :Larry Page and Sergey Brin

Google, the search engine giant and rankas the most visited web site in alexa, has been a changer of the world wide web. Larry Page(born in March 26, 1973) and Sergey Brin(born in August 21, 1973) founded it while they were in Stanford University. their goal was "to organize the world's information and make it universally accessible and useful".

Apple : Steve Jobs

Without any doubt he is one of the best and greatest entrepreneurs in the world. he was born in 24 february 1955 and was able to create the first commercially successful personal computer with Steve Wozniak in 1976. he was the most powerful business man in 2007 according to Fortune's magazine.

Microsoft : Bill Gates

there is no need to introduce this man because is one of the most famous people in the industry being the world richest person for long time he has shown his excellences. he dropped out from Harvard University and then founded Microsoft. now he has left Microsoft and founded Gates foundation with his wife and has become a philanthropist.he was named as one of the 100 most influenced people in 20th century.

Dell : Michael Dell

Dell is one of the largest PC vendors in the world, he first encountered with a computer when he was 15 when he broke down a PC and rebuild it. he dropped out from University of Texas at Austin when he was 19 to run PC's limited which later became the famous Dell Inc.

these are a handful of masterminds of the IT world there are a lot... but these people changed the world and made our lives easier...

Kesh,

Beyond Google, Microsoft, Apple and Linux

2010-02-03T00:18:00.000+05:30

Apple released iPad, HP is going to release Slate, some rumors about Windows 8 and Zune phone.. While all the things happening on the world around i just thought to centralize all those things into one place.

With the release of Windows 7 Microsoft surprise the world in last year. can the software giant continue his legacy ? Linux and Mac OS X were the major competitors for Windows for quite a lot of time but windows prevailed its legacy on the market without too many difficulties. historically Microsoft has made up to 98% of his revenue through partners like HP and Dell but it doesn't seem to be continued. Dell and some of the other PC vendors have a tendency to go for Linux now. Not only Linux and Mac OS X Google the search engine giant recently entered into the scene with their new OS, Chrome OS which is also a Linux variant.
Google however invade everything without doubt he is the search engine giant and then challenge Microsoft with Chrome OS and also with their Nexus one phone and Android they are going to challenge Apple iPhone.
recently Steve Job said “We did not enter the search business,They entered the phone business. Make no mistake: they want to kill the iPhone. We won’t let them.” he did not stop he said to Google "don’t be evil".
However Steve Jobs did not have faith on Adobe or Adobe Flash according to him Flash is buggy and crash prone.
“Adobe is lazy. Apple does not support Flash because it is so buggy. Whenever a Mac crashes more often than not it’s because of Flash. No one will be using Flash. The world is moving to HTML5.”
so, that's the reason why Apple don't support Flash on iPad or iPhone.today, Adobe CTO Kevin Lynch made a reply to Steve Jobs he defended Flash and warns HTML 5 will throw the web back to the dark age of videos. but the battle will continue..
Sun on the other hand was bought by Oracle. so, some people doubt whether it is a blow for opensource. however Oracle is going to challenge Microsoft Office with a new cloud version of Open Office and IBM is also taking on Microsoft sharepoint with Lotus.

everything is a competition everyone challenges but some day it will affect the normal user in a good way because competition makes the best out of best.

Kesh,

Rumors about Windows 8

2010-02-01T19:49:00.001+05:30

After the release of Windows 7, the world is looking to see the next surprise Operating system from Microsoft which named as Windows 8 for now. As rumors said Microsoft has planned to release the RTM of Windows 8 in July 2011 but yet the dates are not confirmed. recently post Windows 7 screen shots has been released by Microsoft and possibly it can be Windows 8 later.

here is a screenshot which we imagine what Windows 8 look like :

Is Windows 8 compatible with 128 bit ?

as lot of people believe Windows 7 is Microsoft's last 32 bit Operating system which means from Windows 8 onwards it is 64 bit and will it support 128 bit? it seems that they are certain that Windows 9 can be released as a 128 bit OS but not sure about Windows 8.

here are some unofficial Windows 8 wallpapers :

however we have to wait and see........ !!

Kesh,

HP Slate, The new competitor of iPad

2010-02-01T13:46:00.003+05:30

Recently Apple introduced their latest product iPad and it is one of the hottest news in the technology arena for last few days with the new release Apple has challenged Amazon Kindle and other tablet computers. but yet it has some ups and downs. there's no camera in iPad no support for Flash. Steve Jobs recently said they didn't use Flash because of it's buggyness and according to him the world is moving towards HTML 5.

The New Apple iPad

However, Apple is not alone in the competition. few days ago, HP released the prototype of their Slate in a video :

however they haven't said when they are going to launch it but hopefully it is somewhere in 2010

HP slate preview :

Find out your Hardware information

2010-01-20T19:35:00.000+05:30

Sometimes when we are using our Linux box we need to get information about our hardware. so, linux has shipped with a buit-in tool for that it is called dmidecode.

How to use dmidecode

it can be used as a normal command you just need to type it on the terminal as the super user then system will list all the informations about your machine's hardware.

sudo dmidecode

since this command give quite long list it is better to pipe this command with more command.

sudo dmidecode | more

that's it you can easily see what is you motherboard type, version, brand, proccessor version,barnd, information about RAM and many more..... try it..

cheers !!
Kesh,

Get you hands on Erlang

2009-11-26T16:36:00.000+05:30

How to install ?

if you are using linux just type

sudo apt-get install erlang

on the terminal then it will automatically installed in to your machine.

OR

you can visit www.erlang.org/download.html and download and install erlang.

First glance at Erlang

ok.. now we are done with installation so, let's move on to next step...
get the terminal and type erl on it.
you will see
1> kind of a thing...
first let's use it as a calculator :
to do that you only need to type a statement and after the statement put a dot (.) and press enter.
e.g :

1> 123 + 77.
200
2>

DO NOT forget that DOT..

Compiling a erlang code..

let's write a simple code to calculate factorial numbers and compile it.

write the below code in a text file and saved it as test.erl

- module (test).
- export([fac/1]).

fac(0) -> 1;
fac(N) -> N * fac(N-1);

ok now it is done let's compile and run it.

on the terminal write

c(test).

we use c to compile.

and to run..

test:fac(10).

That's it so, i think that may give you an basic idea of erlang i will write some articles about erlang once i have time..

so, enjoy,
Kesh....

Concurrent programming with Erlang

2009-11-20T17:45:00.000+05:30

What is concurrent programming ?
it is a form of computing where more than one process executing in parallel. it can be executed in a seqential manner in a single processor.

In concurrent programming we use two kind of procedures :

Shared memory communication

where processes use shared variables and by altering it they communicate with each other. there are some issues when more than one process altering a single and shared variables so in order to eliminate that kind of issues we use locking mechanism where we use semaphores, mutex and monitors.

Message passing communication

here there are no shared variables it passes messages asynchronously

Erlang

Erlang is also known as Ericsson language because it was originally developed and used by Ericsson but after 1998 Erlang was open sourced. Erlang is a general purpose concurrent programming language and run time environment. it is used by large telecommunication systems.

Erlang uses Message passing communication instead of Shared memory communication so it removes the use of locks.

Erlang's strength is concurrency it has his powerful but a few set of primitives to create and manipulate processes they are not operating system processes or operating system threads but lightweight processes.

we will see how to program with erlang in an upcoming article....

cheers !!
Kesh

Let's GO

2009-11-12T14:39:00.001+05:30

GO..
is a new programming language introduced by Google. It is a compiled language but it has some features of interpreted languages so it has C/C++ like features as well as Python like features. GO is really fast almost like C. this is a lightweight language compared to some other languages and supports multi core machines and most importantly and as usual Google released the new language Open source.

How to install GO

First you need to install mercurial on your machine. if you haven't installed it yet get the terminal and enter this command.

sudo easy_install mercurial

then you have to add an environment variable to your .bashrc file. actually you need to add four environment variables to the .basrc file in order to install GO.

in the Terminal type

gedit ~/.bashrc

scroll down to the last line and add the following lines after the last line of the file

export GOROOT=$HOME/go (you can specify any location)

then save it and restart the Terminal and type

hg clone -r release https://go.googlecode.com/hg/ $GOROOT

and then enter this

sudo apt-get install bison gcc libc6-dev ed

the source code of GO will be automatically downloaded to GOROOT

now we have add another three more environment variables before building the source

so again open the .bashrc file and add the following lines after the last line of the file

export GOBIN=$GOROOT/bin (you can specify any location) , this is the place where binaries will be put.

export GOOS=linux
export GOARCH=386 (put your machines architecture here.. amd64, 386)

and then finally make sure your GOROOT is in the PATH so,add

export PATH=$PATH:$GOROOT

save the file and restart the terminal...
let's build the source and start to GO....

cd $GOROOT/src
./all.bash

right now you are finished if everything GOes well you will see something like that in the terminal (the number of known bugs may be vary from release to release)
--- cd ../test
0 known bugs; 0 unexpected bugs

ok.. now you have installed GO on your machine so, LET'S GO.....

Kesh....

install Java on Linux

2009-09-27T09:55:00.000+05:30

Hi all, Today, I'm going to talk about some very basic things, actually this is a summary of what i did in yesterday workshop.

How to install Java

since java is a platform independent language and runs on a virtual machine we need to install something called SDK (or JDK) in other words Software Development Kit.
there are few ways to install Java

if you don't have an Internet connection but can access internet from some other place here is the way to install Java :

first download the SDK you will get a file with a .bin extension
now go to Applications --> Accessories --> Terminal (in Ubuntu) change the directory place where you downloaded the bin file.

e.g
if your file is in a folder called download in your home directory type :

cd ~/Download

~ is a simple way of typing the path to home directory.
then type
./name of the file.bin
remember this will install Java in the present working directory (type pwd in the terminal if you want to see the directory)

if you have followed the previous steps correctly you can see a license agreement scroll down until you find the end of the license then type y (or yes) and press enter

after few moments Java will be installed in your system.

How to set the environment variable

after installing Java if you try to compile a java code what will happen ?

you can't do any compilations since we haven't set the PATH variable (but if you install java directly from repositories you don't need to do that i will come to that point later)

first type

gedit ~/.bashrc

* in linux files that starts with a dot(.) are the hidden files

then add this line to that file and save

export PATH=$PATH:/path to bin

(click on the image to enlarge)

now exit from the terminal and open it again. now you can compile and run your java programmes on linux.

if you have an Internet connection

then the life is much easier for you you just need to type :

sudo apt-get install sun-java6-jdk

and press enter then you will be prompted to enter your password. after installing java in this way you don't need to edit the .bashrc file.

enjoy this week with Java and Linux
cheers !
Kesh,

Install LAMP with tasksel

2009-09-21T17:00:00.000+05:30

What is LAMP ?

LAMP stands for Linux Apache MySQL PHP/Perl/Python. when it comes to web developing LAMP is the best way for Rapid Application Development using open source technolgies.

What is tasksel ?

tasksel is an installation system that comes with debian/ubuntu systems it groups software packages by tasks and offers an easy way to install all the packages needed for that task.

How tasksel works.

get the terminal and type

sudo tasksel

you can see something similar to the above picture. scroll down to the package you need to install and press space bar then press tab and select ok button and press enter. then the tasksel will do the rest for you.

here i have chosen to install LAMP server.

Is this the only way to use tasksel?

no you can do the same thing with the terminal with this command :

sudo tasksel install lamp-server

sudo apt-get install lamp-server^

** DO NOT forget to add the caret ('^')**

hope you can configure LAMP on your Linux box ... i will come up with the conventional way of configuring LAMP in a future article.

cheers !!

Kesh,

Embed a Wave to Blogger

2009-08-09T00:28:00.002+05:30

Google Wave which is one of the latest technologies introduced to the world is still on developer preview but it has gained a lot of popularity amongst the developers as well as the public because the general public eagerly waiting to experience the Google wave and it is new and cool features. Google will release wave to the public may be later in this year.

Since there are not many articles about Google wave APIs this article has been written to fulfill it. here Embed API has been discussed. this shows how to embed a wave to a blog.

in order to embed a wave you need to have a Google wave account.

this article shows how to embed a wave in a blog created with blogger so you need to have a blogger account.

here are the steps you need to take to embed a wave in to your blog (there is a robot called bloggy which can update blogs but this is not about bloggy)

go to your blogger account and select Layout
click on a Add Gadget then chose HTML/JavaScript and click on the +(add) button
enter the following code

<script src="http://wave-api.appspot.com/public/embed.js" type="text/javascript"></script>
    <script type="text/javascript">
    function initialize() {
      var wavePanel = new WavePanel('http://wave.google.com/a/wavesandbox.com/');
      wavePanel.loadWave('wavesandbox.com!w+yourwaveid');
      wavePanel.init(document.getElementById('waveframe'));
    }
    </script>
<div id="waveframe" style="width: 230px; height: 300px"></div>

where yourwaveid is the wave ID which you wan to embed to obtain the wave ID first go to Google wave and click on debug and choose wave ID you will get the ID of the current wave and insert it there.

then click on Edit HTML
navigate to the place where starts (Ctrl + F and type <body )
add this line onload='initialize()'

so it will look like

OK... now time to check it.... you can edit the wave from the blog it is really cool... but you must have a wave account to see the wave.

Enjoy,
Kesh,

NetBeans 6.7 supports project Kenai

2009-07-16T19:51:00.002+05:30

Recently, NetBeans released their latest version which is 6.7 with a lot of new features including the support for Google App Engine and Project Kenai.

What is Project Kenai

Project Kenai is a platform for open source project hosting like Sourceforge and Google Code. once you register with Kenai you can search for a project and get involve or even host your own project. if you have a SDN account(Sun Developer Network) you can use it is username and password to login to Project Kenai.

How NetBeans helps Project Kenai

If you don't have NetBeans 6.7 download from here.

the difference i see in NetBeans 6.7 is it helps to connect developers and to collaborate with each other.

here is how NetBeans support Kenai :

the circled place indicate whether you have log into Project Kenai if it is not green click on it and then you will be prompt for your Kenai username and password or SDN account details.

now goto window and choose Kenai dashboard then you will see your Kenai dashboard with the projects you have been involved in.

this is the Kenai dashboard using this dashboard you can view projects that you have already involved and download the source codes via svn. find issues which were reported earlier or report a new bug.

not only that as declared earlier it helps to collaborate with developers while you are doing a project you can chat with the other developers who are doing the same project.

as FOSS enthusiast we always love to get involve in big projects and host our own projects and this can be the initial step for it......

enjoy........

Kesh,

Starting Flex..

2009-06-30T13:00:00.006+05:30

Though Flex is so much powerful technology why don't we use it. oh ! we can't use because we don't know Flex right? ok ok, from today onwards i will write a few articles on basics of flex. but this blog is not a flex tutorial it is all about new technologies so i will address some other topics as well.

Prerequisites :

you must have installed Flex builder 3 or Flash builder 4.

a knowledge of using an IDE like eclipse, NetBeans (but not essential)

prior knowledge in programming in Javascript, Action Script, XML or an Object Oriented Programming language is an added advantage.

well i have read so many introduction tutorials or articles to any programming language they all start from a simple Hello World application so, here i will also obey that rule and show you how to build a typical Hello World program.

first open Flex Builder 3 and create a new flex project.

then choose a project name for your project. and use application type as Web application but if you need to create a Adobe AIR application you should select Desktop application. select the server type here i've used none but if you are planned use any other Technology like JSP/Servelets, PHP, .NET use should select the server appropriately.

after creating the project now you can develop an Adobe Flex application.

well let's create a simple button and an alert saying hello once the button get clicked.

go to the Design tab and drag a button from the components palette and drop in to the window area.

then go to the source tab again.

you will see something like that :

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
<mx:Button x="128" y="120" label="SayHello"/>
</mx:Application>

now, let's add some action script to the code to get a pop up(alert).

first add a <mx:Script> tag within the <mx:Application> tag.
then add an import declaration.

import mx.controls.Alert;

in the <mx:Script> tag. since we are going to get an alert we have to import Alert in to our application.
then we'll create a simple method which shows a simple alert saying "Hello World"

function sayHello():void{
Alert.show("Hello World");
}

since we don't need to return anything from the method we declared it as void. Alert.show(title:String) use to pop up a simple alert.show() has some other overloaded versions you'd better try all the things your own.

ok.. now the scripting thing is over. let's add a click event to the button so when the button is being clicked that alert will be shown.
in the <mx:Button> tag add click="" attribute and call the sayHello method from it.

<mx:Button x="128" y="120" label="Button" click="sayHello()"/>

here's the full code snippet

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
    <mx:Button x="128" y="120" label="SayHello" click="sayHello()"/>
   <mx:Script>
    import mx.controls.Alert;

    function sayHello():void{
    Alert.show("Hello World");
    }
    </mx:Script>
</mx:Application>

now right click on HelloWorld.mxml file and click run application.... or click Run menu and then click on Run HelloWorld or just press Ctrl+F11

here we go............

here it is.... there are so many in built components in Flex you'd better test them with with your own have fun.................

Google Language API

2009-06-19T16:59:00.001+05:30

Language is the main communication method use by human beings there are so many languages exists in this world as a global language we use English but there are so many problems arises because of this language barrier sometimes we need an interpreter to interpret our language when we speak with a person who doesn't know the language which we are speaking to overcome that kind of problems Google has introduced an API called Google language API it helps to translate one language to another currently it supports to pair more than 30 languages and it is still growing.

you can find out about language API from here

you can easily use this APIs and integrate them into your websites without any server side code. you only need a google account to get a API key and simple javascript code.

i will show you how to load an Google API to your website:

< script type="text/javascript" >

google.load("language", "1");

< /script >

in this way we could load the language API to our application in that load method:

load("Module Name","Module Version")

since the language API is still version 1 i have put 1, if you want to use Map API you can say:

google.load("maps","2")

this is the way you load google APIs to your website i will show your some codings to how to create simple gadgets using google APIs in my next articles.. until then try to build some gadgets with your javascript and html knowledge it is very easy

Kesh,

Basics of JavaFX

2009-06-17T00:24:00.007+05:30

I think you have enjoyed with my previous article. so today i am going to explain the code line by line. here's the code again :

import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.text.Text;
import javafx.scene.text.Font;

Stage {
   title : "My first JavaFX application"
   width : 250
   height : 200

scene : Scene {
   content : [
   Text {
    content : "Hello World"
    x : 10
    y : 20
   font : Font{
    name : "Times New Roman"
    size : 14
   }
 }
 ]
}
}

if you know Java or any other Object Oriented programming language you know what are objects and what are those import statements says.

we have imported some external classes which were defined in the API to our Main.fx file. those are Stage, Scene, Text and Font.

Stage

Stage is the top level container window required to visible any JavaFX object.

Scene

Scene is somewhat similar to a drawing surface for your applications graphical objects.

in side the Stage object we can see instance variables called title, width, height it defines the title which appears on the windows top border and the windows width and height.

the content variable can contain an array of Scene objects in this example it has a Text object and a Font object.

In that Text object we can see another three variables content, x, y .defines the the content of the text and it's x, y coordinates.

I think you can figure out the scripting language easily... if you have any problems please leave a comment

ok,,,, i will come up another new technology later have fun............

Kesh,

Say "Hello" from JavaFX

2009-06-15T19:54:00.002+05:30

This time i am going to introduce you to the codings from today onwards you can get your hands on JavaFX but don't forget this is not a JavaFX or Flex tutorial this blog is meant to discuss about new and emerging technologies in the process of discussion whenever it is appropriate i will introduce you into the codings....

Prerequisities

as i said in my previous blog you must install JavaFX SDK but i recommend you to download and install NetBeans 6.5 which is compatible with JavaFX go to this link and download it.
some kind of a knowledge in programming is an added advantage but since i start this from the scratch no need to be panic :-)
knowledge of using NetBeans is preferred but once you are doing codings you may get to know about NetBeans.

Let's start coding............................................

start NetBeans (JavaFX compatible) and do the following:

file --> New Project
select JavaFX and click Next
give a project name and choose a location
click finish

great.... now we have created our first JavaFX project. since we are going to start from scratch let's delete all the contents in Main.fx file :

Before moving into codings i must say something about the language use here. it is a simple scripting language, JavaFX scripting language however, without introducing XML type of a language Sun has decided to introduce a language much similar to Java.

OK, back to coding,
first import and create a Stage object : write the following code in your Main.fx file

import javafx.stage.Stage;
Stage {
}

believe me that's all, this is a simple and working application but you will only get an empty frame most precisely a Stage.

so, let's add some content :

import javafx.stage.Stage;

Stage {
title : "My first JavaFX application"
width : 250
height : 200
}

here, we build a simple frame with a title and initialized its width and height.
ok let's go further more let's add a Scene to the Stage and add the Text "Hello World"

import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.text.Text;
import javafx.scene.text.Font;

Stage {
title : "My first JavaFX application"
width : 250
height : 200
scene : Scene {
content : [
Text {
content : "Hello World"
x : 10
y : 20
font : Font{
name : "Times New Roman"
size : 14
}
}
]
}
}

this is the code to say Hello World from our first JavaFX application now run the project : simply press F6

Note : if you are going to copy and paste this code to your NetBeans project make sure to mention your package declaration above the import lines...

enjoy.. with the codes and try to figure out how the scripts works i will come up with an explanation of this code in my next article.. so have a go with JavaFX......

Kesh,

Hands on JavaFX

2009-06-14T17:00:00.001+05:30

Rich Internet Application development is one of the coolest things to do as a programmer because without much effort and without much knowledge in graphic designing or web designing we could develop stunning web application with dynamic, user friendly and beautiful User Interfaces.
JavaFX is also a new technology introduced by Sun Microsystems.JavaFX is not only a framework to build RIA but it can integrate lot of audio and video resources and lot of effects to your application.
to get inspired watch this samples :

recently Sun released JavaFX SDK 1.2 with lot of new features you can download it from here
and also you can download NetBeans 6.5.1 which is compatible to develop JavaFX along with JavaFX SDK from here

I will come up with some more articles on JavaFX later so be prepared to get your hands dirty with JavaFX. we will exploit JavaFX and build some rocking applications.

Kesh,

What is Adobe Flex ?

2009-06-11T13:42:00.001+05:30

World Wide Web is very familiar for every one of us and it is changing rapidly. As human beings we don't satisfy from what we get and usually a human is very curious with the combination of that two behaviors they tend to invent new things and new technologies hence, the technology and almost every thing particularly on web growing and improving very very fast.
In early days of World Wide Web, it tends to consume much time because all the processing were done in the server once the browser sends a request to the server it did all the processing and send a response so, it took much time.
but with the technologies like AJAX(Asynchronous Javascript And XML) the consumption of time change dramatically now we have powerful machines good web browsers so some of the processes can also be performed in the browser without requesting from the server it saves time. time is money so indirectly it saves money.
RIA (Rich Internet Applications) has revolutionized the world with its power, beauty and user friendliness. RIA along with Flex makes life much easier for the developers to build sexy and powerful web applications.

Adobe Flex

it is a open source framework
can be easily develop on Flex builder (now Flash Builder 4)
use MXML (a XML Markup language) and Action script

Flex Builder

Flex Builder is an IDE for developing Flex applications now, in their new release they named it as Adobe Flash Builder 4. even you can add a plugin to Eclipse and develop Flex applications on Eclipse
to download Flash Builder 4 (but still beta) you must register with Adobe to download it.

MXML and Action script

MXML is a XML Markup language and it is being used to create UI components it is really easy to create UI components with XML so then they can be re-used very easily.
Action script 3.0 which has been used by Flex 3.0 is responsible for controlling the behaviors particularly the logic of the application

If you know PHP, JSP/Servelets, ASP .NET, Cold Fusion or anything you can integrate Flex application with them.

the only requirement to run a flex application is you should have Adobe Flash Player installed. flex is cross platform and supports almost every browser which supports Adobe Flash player.

this is the introduction if you are not clear please leave a comment and hope to introduce you to some codings in next posts. until then have fun.................

Kesh,

Introduction

2009-06-10T22:36:00.000+05:30

Hi all, this is Keshan and this is my first ever technical blog in English i have another blog in Sinhala http://crazykesh.blogspot.com and i have written some poems in both Sinhala and English http://keshlectures.blogspot.com if you like you can have a look at them.

I am a currently an undergraduate of University of Colombo School of Computing and I am Sun Certified Java Programmer and a Sun Certified Mobile Application Developer.

ok this is my voyage in the ocean of latest technologies. here, basically i will address on Flex, Linux and FOSS, Java ME , Java EE and many more………….. So, Keep In Touch

Kesh,

Contact Me

2009-06-09T12:52:00.000+05:30

e-mail : kesh.jboy@gmail.com

Contact Form under construction :