Creative Crap ;)

IT Primer

2009-06-18T23:45:00.000+05:30

Table of Contents
Struts 2. 2
Java Concurrency Package. 2
Spring. 2
UML. 3
Oracle 10g Features. 3
Oracle Indexes. 3
Java 1.5 features. 3
Java Misc. 3
Java Back to basics. 4

Struts 2
1. Based on Open Symphony WebWorks framework
2. Action classes are POJO
3. Action classes are not singleton and can have instance variable
4. No ActionForm
5. Uses interceptors i.e. filters rather than controller servlet
6. ValueStack and OGNL are new features. ValueStack is memory area where the data for the request resides in a stack. OGNL is Object-Graph and Navigation Language, an expression language for accessing values in ValueStack and type conversion.
7. Single Tag Library
8. *.action is default v/s *.do
9. Annotation support

Java Concurrency Package
1. Filling the void by providing support for high level synchronization
2. Executor.execute(runnable), PooledExecutor, QueuedExecutor etc
3. FutureResult (Call back mechanism)

Spring

UML
1. Use Case Diagram: Shows type of objects and static relationship between them.
2. Class Diagram: Attributes and methods
3. Package Diagram: Group classes into package
4. Object Diagram: Shows objects instead of classes, useful for complex objects
5. Sequence Diagram: Interaction diagram what messages are shared between whom and when.
6. Collaboration(Interaction) Diagram: Same as Sequence Diagram, focus on object roles instead of time
7. Statechart Diagram: Shows possible states of object and their transitions that cause change in the state
8. Activity Diagram: Fancy Flowchart
Oracle 10g Features
1. Automatic Shared Memory Management
2. Database tuning improvements (Self and automated)
3. Scheduler utilities through new package dbms_scheduler
4. SQL Regular expressions for search and replace

Oracle Indexes
1. Bitmap: For columns with very few unique values (low cardinality < 1%), Tables that have no or little insert/update are good candidates (static data in warehouse), fast to read, overhead on maintenance
2. B (binary) Tree: Leaf, root, node, order, depth
Java 1.5 features
1. Annotations
2. Generics
3. For loop
4. Auto boxing and un-boxing
5. Var Args
6. Enum
7. Static import
8. Scanner API
9. Format System.out.printf(%s) etc
Java Misc
1. Hotspot is java virtual machine which supports Just in time compilation and adaptive optimization. JIT compiler converts bytecode to native machine code just before the execution. Adaptive optimization is a technique of dynamic recompilation of portions of a program based on the current execution profile.
2. To make a class immutable, do not provide setter methods i.e. the method which could mutate the state of the object. Also make the variables private and final. Make the class final to avoid subclassing. String, Integer, Double etc. are immutable classes
3. Java.util.vector: As of the Java 2 platform v1.2, this class has been retrofitted to implement List, so that it becomes a part of Java's collection framework. Unlike the new collection implementations, Vector is synchronized. The Iterators returned by Vector's iterator and listIterator methods are fail-fast: if the Vector is structurally modified at any time after the Iterator is created, in any way except through the Iterator's own remove or add methods, the Iterator will throw a ConcurrentModificationException. Thus, in the face of concurrent modification, the Iterator fails quickly and cleanly, rather than risking arbitrary, non-deterministic behavior at an undetermined time in the future. The Enumerations returned by Vector's elements method are not fail-fast. Capacity increment can be specified in Vector but not in ArrayList.
4. Java.util.Comparator: int compare(Object O1, Object O2). -1 if O1 less than O2, boolean equals(Object o)
5. TreeMap implements SortedMap

Java Back to basics
1. Overriding: Same name, number and type of parameters and return type, can return subtype, wider access specifier is allowed.
2. Java Class Loaders: 1) BootStrap/Primordial class loader which loads JDK internal classes (rt.jar) 2) Extensions classloader which loads jar from JDK extensions directory (lib/ext) 3) System classloader loads classes from classpath

Database Back to basics
First Normal Form (1NF):
Eliminate duplicative columns from the same table.
Create separate tables for each group of related data and identify each row with a unique column or set of columns (the primary key).
Second Normal Form (2NF):
Remove subsets of data that apply to multiple rows of a table and place them in separate tables.
Create relationships between these new tables and their predecessors through the use of foreign keys.
Third Normal Form (3NF):
Remove columns that are not dependent upon the primary key. (Total)
Fourth Normal Form (4NF):
A relation is in 4NF if it has no multi-valued dependencies. (Course/Book/Teacher : Course-Book and Course-Teacher)

Yellow

2007-06-06T21:46:00.000+05:30

Yellow...! The sunshine color..! On a normal day, I would have liked this color, but on that Friday, it seemed otherwise. I guess it was trying to steal sunshine from my face. (I know there’s not much either!). The yellow color was on my module’s task status report sheet, indicating that our module had come of the soothing green ages and was marching towards burning red.

I tried recollecting all the cheering-up ideas but came up with none, and eventually sent an email to the team, trying to squeeze more out of them. In the professional world, it looked like a ‘cheer-up’ email, but in reality, I was probably hoping that they would willingly screw-up their weekends and work, which was exactly what I was planning for myself.

Friday was running faster than I expected it to. All the pending tasks, those small – little things, which were now looking like a monster to me and spinning around my head. Having dropped the idea of calculating the centripetal and centrifugal forces for the same, I thought of knocking them down one by one or get knocked out. Will they revolve around my head faster, had I had more hair? Stupid question, I thought!

I was really busy (I mean it!), and that’s when the mobile rang. Annoyingly, I picked it up.

“Hello Sir, this is Salil here.” – The phone said.

Salil …! Trying to google it in my mind but in vein for this name, I had to re-look at the phone. Thanks to my phone, it said “Project Trainees”.

I merely replied “Hi”.

“Sir, we have completed our project, we can show you the demo provided you allow us to carry our laptop in your premises. And also we require the certificate from your organization with your signature on it as our project guide.”

Trying to make sense out of what he said, I quickly realized only one thing; I was short of time for all that, especially on the Yellow Friday.

“That’s good news – having completed your project. Can you wait for some more days for the demo and the certificate?” I asked.

I still wonder how could I manage to say that this was good news, I guess because they had done it without much guidance!!

“No, Sir, Actually we have to submit it on Monday,” the phone said.

I was furious … as if I didn’t have any deadlines from my Client, here is one more deadline. Before spitting out my anger on the phone, I paused for a moment. I recalled the submission days and deadlines during my engineering days.

Oh boy, that was a real mess…! My project was for Nylon manufacturing plant, but instead of how Nylon is manufactured, my concern was how to get Nylon binding done for this project submission!!

Having realized the criticality of submission phase of the project trainees, I said – “Come down to the office, I’ll arrange for the certificate today itself”.

Having put my tasks on hand onto the shelf, I arranged for the certificate with HR.

In evening, at about 6 pm, they came. I thought I would just give them the certificate and that would be it.

I was in the elevator, going downstairs, to hand over the certificate, when I thought – “What about the demo? How can I give them the certificate without even making sure that they have indeed completed the project? What if they have not?”

Having realized that my organization’s reputation was at stake, I decided to see the demo, and that meant sacrificing some more TIME!

“How about a demo before I give you this?” I said, showing them the certificate.

“Sir, we haven’t brought the laptop, but we can call up my friend, he will switch it on, connect to internet and we can show you the demo online.”

It meant only one thing to me – more TIME!

“Sounds interesting”, I said. I brought them to my desk.

After some telephonic conversations, finally their site was up and they started giving me screen by screen demo. The reviewer in me took the front-seat replacing the programmer and I started giving them my comments/suggestions.

They had questions and for me it was only one thing – more TIME.

“We have a session related issue, if the user logs-out, he can click back and can still access our site” – one of them asked.

Here comes the bouncer from the minnows, I thought. I googled for the answer in my mind by clicking the imaginary radio button – “pages from my CDAC days.

“You should invalidate the session on log-out.” I replied, trying to dodge the bouncer.

“We are doing that, we are in fact removing the session variables.” – He said. (Yorker, this time.)

“There is some method to invalidate the session”, I dug it out and actually googled it and showed them the method signature.

After few more overs, I was still at the crease, surprisingly!!

“Thank you very much, Sir. That was a great help” – One of them said.

Relieved to a great extent, I handed them the certificate, congratulated them for the good work, wished them good luck and escorted them to office gate.

While going downstairs in the elevator, out of curiosity, I asked “How come you got permission for your project in this organization?”

“Actually Sir, my dad is a close friend of Deepak Sharma!”

(Vice President of my organization – name changed)

Bidding them goodbye, I was thinking only one thing…

“Had I known this fact before, would I have spent even more time on guiding this project on this Yellow Friday?”

The honest answer that came from within is “No” bringing some sense of accomplishment, which really felt good.

Back on my desk, the sheet was still showing “Yellow” but it was somewhat soothing now.......!

Freshaayari

2007-01-03T19:44:00.002+05:30

*********************************
Tanhaayi me teri yaadein,
Mehfil ka rang bhar jaati hai,

Mehfil me wohi yaadein,
Hame tanhaa kar jaati hai.....!

*********************************
Hothon pe ibaadat bhari hai,
Aankho me chaahat gehri hai,

Hai to woh sahemi si ek ladki,
Jaane kyo lagti woh paree hai...

*********************************
Jhulas jaoge is aag se,
Chingario se khelna chhod do....

Bahek jaaoge in baaton mein,
Yu paas aana chhod do..!

*********************************
Kaash hote kuchh fasaane bayaan,
Ya fir afsaana hi hai naam inkaa....!

Kaash hote kuchh sawaalo ke jawaab,
Ya fir 'kaash' hi hai jawaab inkaa....!

*********************************
Shaayaro Ke Khauf Se,
Chhoda Hamne Har Shahar,

Anjaan The Ke Zindaa Hai Yaha,
Har Shakhsh me ek Shaayar..!

*********************************

कुछ आहट है हवाओं में,

जाने कौन आया है ?

या कुछ भूली-बिसरी यादों ने,

फिर दरवाजा खटखटाया है ?

गुजारिश है न दस्तक दो तुम यहाँ,

बड़ी मुश्किलों से घर बसाया है !

छुपा लेता हूँ आने वाले कल को दिल में,

जैसे आज को अपने कल से बचाया है !

************************************************************************************

I-Extend

2006-07-14T20:03:00.000+05:30

I-flex has organized a contest. That goes like this 'Biscope-Discover the director in you!'. Participant has to submit a short movie of 3-10 minutes duration. If won, the movie will be screened during induction in i-flex. I have made small home made 'movies' about my friends. Other colleagues were also enthu' about this. So we sent our registration.

The movie theme - as proposed by Jitendra Bhansali, is to show activities for the benefit of community by i-flex. The topic itself is good. During my induction, there was nothing that covered this dimension of i-flex.

I titled it 'i-Extend'. I-flex has this tendency to prefix 'i' like 'i-assist', 'i-share'. 'Extend' is the way i-flex is extending its hand to society.

I started collection 'material' for movie, only to find out that its not easy to get media clips etc from corporate communications group of i-flex. The responsible guy was on leave and that virtually shut the CCG doors for us. I relied on iflex intranet and googled some other stuff.

Without having video clips, one thing was sure. Our 'movie' will not be the movie in true sense. With only pictures and text, I had to create a 'movie'. I used Windows movie maker ( I had no options as I know and have worked on windows movie maker only ). I tried as many effects as I can, to provide some kind of motion (infusing life) to still images. For background music, I dragged my favorite slow song of the one movie [I edited this post later and removed name of movie to prevent any copyright trouble ;) ] into movie maker and chopped it apart. I selected the starting piece of song and used one more piece as filler. I kept on repeating 2nd piece for entire length of movie.

My most enthusiastic teammate - Mandar - himself needed enthu. He was ill and hence on leave. I missed him. But, Sachin, thanks to him, roped in. The movie was about 90% ready when I showed it to Sachin. Sachin liked it [that's what he told me :)]. He suggested me one brilliant idea. He told me to add introduction before the movie so that audience will have idea of what they are going to see. [I guess, while watching the movie, for the first half, he could not figure out what the heck was being shown ;)]. Introduction, that means background voice, like Mr. Bachchan in Lagaan. Now, question came, who will read it ? Immediately I thought of Prashant Rao. I knew that his voice is best fit for this. He has this 'strong' voice. [That's what I think ;)] We 3, sat together, got script ready and he recorded it many times before finalizing. Oh, boy.. hard work !! ;)

Finally, my colleagues started seeing the movie and I guess, they liked it. [At least, that's what they said. C'mon, no matter how bad your movie is, no one is going to say it 'bad' on face. I guess this is what they call 'professionalism' ;)]. Some of them like Talib and Jitendra came up with very good suggestions.

Well, the 'movie' is not a movie, but what I can say is, it is somewhere between an advertisement and a powerpoint presentation.

Let's wait for the result of contest...

**************************************************************************
Update:
Bad news is, i-Extend was not a winner. Good news is it received some appreciation from jury (that's what I was told ;). The other movie - Life@i-flex, in which I contributed, won the 2nd prize. The team received cash prize and I was given a nice cute photo frame, having team picture, signed by all team members. It is here.. lying on my desk.... nice moments to cherish.
**************************************************************************

Skiing - Sub-zero learning

2006-06-20T21:41:00.000+05:30

(Jan 22, 2005 )

We went for skiing on Paoli peaks, Indiana on this day. It was about 65 miles from where we used to stay, Louisville, KY. We were about 10 people in 2 cars. We reached there around 1:30! It was cold day and it was snowing on the way. We bought one-day pass for $45 and took skiing gear on rent for $25. It was my first experience. We knew that it is going to be difficult for the first timers, but we were ready to take the gamble, as it was exciting.

The ski-shoes were too heavy and it was quite uncomfortable to even walk on it. We had winter gear, which we thought were enough to protect us from cold, but we were proved wrong!

I started and fell within first 5 Ft. It was windy and I almost lost sensation on my face. I thought of giving up when I fell thrice. But I decided to stay on. I removed my ski and walked holding them in hand. I headed for plain area. There I started skiing. It was successful move. Now I was covering more Ft before felling down. Some of us fell 30-40 times but it was fun.

One of my friends fell. While he was lying on snow, one small kid came to rescue him and told him "Skiing ....Oh boy, that's tough!"

It was so chilly that my palms were almost frozen. The winter gear was not enough. All of us were finding difficult even to speak. But, one thing to note down here is, 'no matter how cold it is , no matter how severe is the pain, but everybody was laughing out their hearts when they fell. Little School kids were skiing swiftly by us when we were lying flat on the snow.

One thing, which we all learnt pretty late, was to remove one of the skis before trying to get up from the snow. Initially, we were trying to get up with both skis on and were falling again in that attempt.
While I am writing this, my back is still paining. Well, that was an unforgettable experience.

Note: The photos are available at http://photos.yahoo.com/bhatt_vimal (Album: Skiing)

Proud to be an Indian

2005-10-05T04:55:00.000+05:30

************************************************************************************
Interview : Vanu Bose, Founder, Vanu Inc: The Indian mentality is to be innovative

About Bose - History: "Bose Corporation was founded in 1964 by Dr. Amar G. Bose, then professor of electrical engineering at the Massachusetts Institute of Technology."

************************************************************************************
Tata, true Indian company, launched XOver. It looks really cool ! checkout this URL.
http://www.dancewithshadows.com/autoindia/tata-xover-crossover-car.asp