Five Points To Improve Your Estimation
I recently read an excellent book called “Software Estimation: Demystifying The Black Art"
Lastly, estimation is a skill we can learn and improve over time. You will find that over the months, your developers will get better at estimating based on past experience.
My experiences with pair programming
My initial thoughts on pair programming (definition).
Normally at our shop, we don’t do pair programming. Each developer is assigned his or her own tasks and they are responsible for completing them. If they require assistance of explanation from another developer who is more familiar with that system they need to go and request that assistance on their own. I believe the vast majority of offices work in this manner.
However, yesterday we decided to try pair programming. We have a complicated CRM application where it takes months to learn the application, and the situation is that another fellow who works on the reporting side of things and I worked together to solve a few bugs in the system.
As we worked together (with a slightly decreased speed than the two of us seperately working) we managed to eliminate two instances of duplicate SQL code in our application and instead used a view that already existed which I was not aware of. As well, I am very confident you that this resulted in a much higher quality of the application, even if it took longer. You are far less likely to end up with bugs when you use pair programming.
I am still skeptical if it really was slower or not, because when you work on your own, you can get stuck on a particular problem and waste half a day, whereas when the other person knows it, you can immediately solve the problem and move on. As well, you are less likely to waste time checking the news, weather, etc, because the other person is sitting and working with you. Also, keep in mind that "task switching is expensive". When you are working on a piece of code and you are "in the zone" and then you have to stop to assist someone else, this lowers your productivity, whereas when both of you are concentrating on one issue, you don’t have this issue.
Pair programming can also be used to train or "rough in" new employees, and as well it results in increased code awareness (i.e. both of you are trained on the same piece of code, incase one of you quits or is sick, the other person also has a good idea of the code).
While the jury might still be out on this principle, and maybe its still too "extreme" for most managers to allow it, give it a shot when you have a chance and see how it goes.
Convert your site from VB.NET to C#
If you are tired of the headaches of using VB.NET code, and want to convert it to C#.. Here is a nice way to do it and get the comments too.
Why would you do that? Well if I have to explain to you, then you probably don’t need to do it. One big reason for me is that VB.NET does not support multi line strings. You have to keep putting " & _ at the end of each line making it very difficult to go back and forth from another program with strings. You could technically create a tool to do this for you but that’s so silly. Another thing is I really like using ?? operator in C#, for example txtLocation.Text = (GetLocation() ?? "").ToString() will ensure that even if SomeFunction returns null, this will always give you at least empty string.. I like to use this in cases where I am getting null and its a text box I am setting the text for.
Another reason is that VB.NET code doesn’t force you to type your variables properly, so everything is an object unless you specify, or unless you put on Option Strict
One way to do it is to use Reflector + Code generation add-in, but you will lose the comments and maybe even variable names because it uses the intermediate language (IL) from the DLL to re-make the source, so it’s pretty useless to do it this way if you want to keep your code in the long run.
The way I like is to use a site such as http://labs.developerfusion.co.uk/convert/vb-to-csharp.aspx
Keep in mind I know there are other tools available that you can pay for, and some that are free too, but this is a quick and easy way to do it at work without requiring any installation.
Once you perform the conversion, the code will still have some things that need to be manually converted.
One thing is this site does not compile the code, so it does not know if the VB code .Rows(5) is actually a function call called Rows with a parameter 5, or its an array index [5]. So you will need to fix these manually.
Same thing with Tables[], Session[], etc.
Sometimes with VB code you will see .Item being used when no such thing exists in C#, you just use the square brackets to get the item directly such as .Rows.Item(5) in VB.NET is equal to .Rows[5] in C#
Here is how you can search and replace these with a regular expression.
Search: \({(["|a-z|A-Z|,|0-9|\:|\.|_])+}\)
Replace: [\1]
You have to do this manually and confirm each one.. Or make it more smart by searching for keywords such as QueryString, Cookie, Value, etc.. and replace all, then do the rest manually
The next thing is that functions such as .InStr are not supported directly from C#, you need to call Microsoft.VisualBasic.Strings.InStr(…) The code converter will automatically do this, but you need to add using Microsoft.VisualBasic.Strings to the top of your class file.
There are a few more things I could mention, but just try it out and see how it goes.
Here is a few more things
1) "my string" & " is very long" will give an error while converting. Before you run the converter, replace these & in your VB code with + instead.
2) the functions that have handles such as lstItems_SelectedIndexChanged(…) handles lstItems.SelectedIndexChanged need to be taken care of by putting either an event in the ASPX page in the <DropDownList OnSelectedIndexChanged="lstItems_SelectedIndexChanged"
Also, they might be private, so you need to make them protected. Here’s a regexp to start you off:
find: {(protected|private)} void {(lnk|lst)}
replace with: public void \2
3) Functions that have optional parameters need to be taken care of. An easy way to take care of this is to create another function that calls the second one that passes the default value with the same name. That easy!
By the way, since I am not regularly writing here, I would suggest you subscribe to my feed so you can get an update when I post a new article.
Timing is EVERYTHING
Being a person who believes in continual improvement, and being proactive instead of reactive, I suggested to one of my employers that I worked for that we should implement ELMAH (Exception Logging For .NET) to handle our uncaught exceptions. They weren’t too interested when I made the suggestion and so I did not push it. I had found this gem of code here because I spend a bit of time each day doing research and improving my skills. (see point 2)
However, we had this continuing problem where customers would have a problem with the .NET site, maybe they had a crash and we had no way to diagnose the crash other than to remote into their machine and try to reproduce the error. What made it worse is that they had debug mode off, and we could not even see the exact crash details. Often we would have to take a risk and modify their file to put debug on (I say take a risk because if you make enough modifications, the application will restart and kick everybody off the system) and this was a live site with real customers.
So once the problem was large enough that it was passed on to the development manager. When he queried the team for possible solutions to that particular crash, I jumped at the opportunity to suggest ELMAH. The sale was immediately closed, and within a week we had ELMAH up and running on some of our customers.
Lesson? Wait for the right time to make your suggestions. it can be very effective. Otherwise your advice may be falling on deaf ears.
Also.. this had the same result again when the timing was right we were able to successfully convince our development manager to make the switch from SourceSafe to Subversion. We had discussed it many times but we had to wait for just the right time and when this time came (since they already knew about it and liked it, but were just waiting for a good time), getting approval from management was easy as pie.
How Random is your Random??
Computers are very deterministic. What that means is that you put something in, you get something out. In order to get computers to perform "randomness", it is very difficult.
* true hardware random number generator developed by Intel [3], which uses thermal noise as an entropy source
Shuffle Highlights:
* Furthermore, we apply conservative rules to enforce the required degree of randomness; for instance, if user input does not generate required amount of entropy, we do not start the next hand until we obtain the required amount of entropy from Intel RNG.
* We use the SHA-1 cryptographic hash algorithm to mix the entropy gathered from both sources to provide an extra level of security
* We also maintain a SHA-1-based pseudo-random generator to provide even more security and protection from user data attacks
* To convert random bit stream to random numbers within a required range without bias, we use a simple and reliable algorithm. For example, if we need a random number in the range 0-25:
o we take 5 random bits and convert them to a random number 0-31
o if this number is greater than 25 we just discard all 5 bits and repeat the process
* This method is not affected by biases related to modulus operation for generation of random numbers that are not 2n, n = 1,2,..
* To perform an actual shuffle, we use another simple and reliable algorithm:
o first we draw a random card from the original deck (1 of 52) and place it in a new deck – now original deck contains 51 cards and the new deck contains 1 card
o then we draw another random card from the original deck (1 of 51) and place it on top of the new deck – now original deck contains 50 cards and the new deck contains 2 cards
o we repeat the process until all cards have moved from the original deck to the new deck
* This algorithm does not suffer from "Bad Distribution Of Shuffles" described in [2]
[3] "The Intel Random Number Generator" – http://www.cryptography.com/resources/whitepapers/IntelRNG.pdf"
Here is a snippet of how to get Cryographically safe random numbers:
This will fill in the 8 bytes with a crytographically strong sequence of random values.
byte[] salt = new byte[8]; RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider(); rng.GetBytes(salt);
Understanding Your 10 Days Vacation
This article is based on Canadian vacation laws.
It seems that most people don’t understand that by law we get 4% vacation. So where does this number of 2 weeks come from?
Well If you calculate 50 weeks * 4%, you will end up with 2 weeks, what that means is in 1 year, you get 2 weeks paid vacation and 50 weeks of work. So if your employer prorates your vacation for the first year, meaning that after 3 months they give you 3/12 of 10 days (i.e. 2.5 days or 25% of your total) but you need to take off 2 weeks and they refuse to give it to you, you shouldn’t worry about because either it means at the end of the year thats all you took (2.5 days paid), and by law they will pay you for the other 7.5 days or 3.75% of your total salary at the end of the year (or whenever they reconcile their accounts which could be a few months later)
The other case is that you will still get 7.5 days vacation after those 2.5 paid days, so in that case you didn’t lose anything and you ended up getting about 2 weeks extra unpaid vacation.
So make a decision, and enjoy your vacation!
How To Debug Inside The Code Of Your 3rd Party Libraries
Let’s say you are using a 3rd Party Library like ELMAH in your web site project to handle unhandled exceptions and it’s throwing an exception and you don’t know why. Since the code is open source, you would LOVE to see what line its crashing on and then submit your changes to the project so that others can benefit from the fix you made. It gives you that good feeling, right?
Well, unfortunately, you put the compiled DLL in the bin folder and when it crashes, it just crashes and burns.
How can you see the source code? Simple! Compile the source code on your machine, and copy the PDB ("Debugging Database") file to your bin folder along with the DLL, and then your web site crashes while in debug mode, it will go to the exact folder on your file system where the DLL was compiled from and show you the exact line of the error.
This was my recent experience with Elmah that it was crashing due to the fact that XMLWriter was misbehaving and throwing an exception when it was supposed to actually replace invalid entities in the XML automatically (at least, according to the MSDN documentation).
Take a look at Issue 43 on Elmah Site for more details.
Get A Build Process Now!
)More to come soon. In summary – CruiseControl makes a world of difference. Get it now.
As Jeff Atwood wrote, "The F5 key is not a build process"
100 Visitors a Day
This site has now grown to 100 visitors a day.. not too shabby But still needs lots of work. I have taken a break from posting for Ramadan but will return soon.
In other news, patch your Subtext 1.5 installation as soon as possible if you haven’t already done so.
SourceSafe Branch Recursively
Did you know there is no way to branch sourcesafe projects recursively? Or so you thought!
Here is a work around:
From Visual SourceSafe Explorer, go to View -> Search -> WildCard Search
Then search for Wildcard: *
(a single asterisk) with "Search in current project and all subprojects" selected.
Then it will give you a list of ALL of your files in that project. Simply highlight them all and click on the Branch button.
The only caveat is that you need to make sure the files are not checked out in that project in order to branch them.
And again,.. I would recommend you ditch SourceSafe and go for something better, like Perforce, Subversion, or Vault