Thursday, October 7, 2010

ExtJs Another Java Script Frame Work

Recently I was working with ExtJs. Its a really nice cool java script frame work. Its really useful for developers to create Rich Internet Application. The biggest problems with java script is browser compatibility, internationalization and maintain it.
ExtJs has solution for all this problem They work in all major version of browser. It support internationalization
The best thing is ExtJs can go easily with any other java script frame work.
It has inbuilt support for Ajax calls. Handling Json response.
There are some cool component ex: Tree, different Chat  which is very easy to use and feed the data.
of course it support all basic HTML,XML and XSLT.
Happy Coding ...

More on ExtJs

Saturday, July 10, 2010

java inside SAP

SAP is known for its enterprise package solution. As they are opening for Java. I had a chance to sneak inside System. In recent days I had a chance to work with SAP enterprise portal and web Dyanpro. The products are built such a way that they support java and ABAP. And final result will be a web application. The main difference is most of the library are available in SAP and as a developer need to reuse them. And SAP give a very strong environment to run the java. Java can run very smoothly inside SAP. Obviously inside SAP java has to compromise some of its freedom. But its OK who doesn't compromise in this world .

Tuesday, April 27, 2010


When Apple Computer decided to rehire Steve Job back. Nobody has imagined Steve will drop "Computer" from Apple. When industry was galloping with Microsoft Windows, Sun's new wonder internet programming langugae Java. Everybody placing them self in World wide Web, Internet compatibilty ..... Steve job started interdoucing some products with iX. After iPhone it is almost impossible to ignore of  "i".
Th most interesting part in India 70% people get their first digital exprenece through a mobile phone. It is very common to use mobile and still illitrate about computers. The penetration of "i" devices is much deeper than computers. So the $ can be generated form "i" applications or services are much higher than PC. As a java progreammer I am excited I just need 18kb to run my JVM. It is interesting to see which platform will rule in "i" devices.

Monday, March 8, 2010

Size does Matter

Every time a girl dump me. I always think "Pallab its all because of that extra 10 kilo". The center of the body is the center of attraction. Then I hit the trade mill and keep hitting the new girl . Any way when I look at the history of application development. We started with command interactive programs, then nice windows based GUI programs ( thanks to Windows who copied from Apple who stole from Xerox ....). And now a days super sexy web application. From command based program to GUI based programs was a huge difference in user experience. Well when the web application came there was a great difference in designing. My teacher taught me for web application the client should be thin,dumb which can only take input and render the output.
And the the server side programs are like god. For everything they are responsible, Whether mandatory field is missing or calculating age of the user when user has already entered the date of birth.Every time it need to request to server. To keep our server as God who can not fail we have to really spend lots of resource.
In last five years we had some fantastic note book in the market and they ship with some amazing browsers. Now we can not blame IE for every stupid script error. It means we can afford to be fat I mean we can migrate something from servers to the client. As our users are already spent good money to have those note book and browsers, lets use them. Allow the client to grow let it become fat .... you will see your application is how intelligent and how it can save money for you ...  So love fat ones because they are smart :)

Thursday, February 11, 2010

New operator is like growing Population !!!

Long back before 3 idiot movie of course even before five point some one. We must have realized life in india is a race. For every stupid thing staring from local bus to admission in higher studies and getting a job is challenging here. Why we have such a situation. The answer is pretty simple we are more than 1000 million people country. And we have not sufficient resource to handle it. Definitely I don't want to advocate here some family planning program or how to stop population growth. All of us know the solution for it. Only we need to use our operators carefully !!!
In our computer world the resource is keep increasing. The computers are faster it has more memory. Still I face the respect full errors like java.lang.OutOfMemory error. I was thinking how can I stop population i mean object population so that they don't have to race for memory,cpu etc. They can have a healthy life cycle.... I checked my code I found 99.9 % time I use new operator to create object ( 1% is the interview tips, we can create object using reflection api and Class.for ...) .
If I can use some kind of protection on new operator things will work .....
Then like conservative use new operator when its really required. You have no other object available to do the job.  then only create the object otherwise reuse the existing one .
Avoid new in Loop.  Less object Light application... Happy Users...

Monday, February 8, 2010

Ajax Restaurant

When and Why We should use Ajax

When first time I learned the term Ajax. I was trying to understand what kind value it will add. Before that I will tell one of my funny experience
I was driving with my friend near to Bangalore. It was 1:30 PM. We were searching some small hotel for lunch. We found a one near to the highway. We went there it was a normal road side Indian hotel. There were few people were eating. We ordered a veg thalli for each. The waiter served us a proper south Indian thalli. It has rice, dal, sambar, rasm, curd etc. i wanted to have extra dal. I asked the waiter "Execuse me can I have some dal please". The guy smiled at me told definitely sir. He took my whole thali inside and brought back the same thali with some dal. It was little strange. I thought why he took the whole thali when I had asked for extra dal, he could get me some dal directly.
So when we design our web pages we can always make choice. To update some portion of the page do we really required to take the whole page away from the user. And the poor user has to wait to get back the page. It is not acceptable when we have such powerful browser which are ready to run java script.
I think bringing only dal is easier rather than serving back the whole meal again :)

Displaying Elements in a tree structure in a web page

The problem statement is how to arrange items in tree structure in a web page

I have googled it and found several open source component. Where we can display the items in a tree.
The below one I found is really handy
Here we can add dynamically elements using jstl or jsp tags. The advantage is we can add icon the style,color and different functionality to the nodes also. It support multi label hierarchy also
The biggest draw back is if there are more than 2000 nodes it gives error in IE "the script is running very slow. Do you want to abort it ?"
To solve this we can do kind of lazy loading. For first time load only parents and on click of the parents load the children by Ajax.