Quoting from an interview in "Communications of the ACM" 2008 08 with Donald Knuth:
The setup is Donald had written a complete spec and assigned it to bright students and then did nothing to manage them as they implemented the spec.
"To my amazement, the students, who were outstanding students, did not complete it."
Only later when he tried to implement it, did he find that it was not so easy.
"Because going from my specification, which I thought was complete, they had an impossible task..."
He later goes on to point out that even with the most complete of specifications, questions arise every 5 minutes as you write code.
In effect, his approach was waterfall with a Big Design Upfront. What he found was a cornerstone of Agile practices, you need to implement a portion of the project and then you will learn enough to start asking questions.
Thursday, July 31, 2008
Wednesday, July 30, 2008
Fixing: An error occurred while validating. HRESULT = '80004005'
Fixing: An error occurred while validating. HRESULT = '80004005'
The error was encountered when attempting to build a 'vdproj' setup project under Visual Studio 2008.
The underlying problem was a project with a reference to another project that had been removed.
As such the setup could not find the dependency to include in the setup package.
This was fixed by removing the bogus project reference and adding the correct reference.
The error was encountered when attempting to build a 'vdproj' setup project under Visual Studio 2008.
The underlying problem was a project with a reference to another project that had been removed.
As such the setup could not find the dependency to include in the setup package.
This was fixed by removing the bogus project reference and adding the correct reference.
Tuesday, July 29, 2008
Database Deployment Challenge
Getting a database deployed consists of numerous challenges.
One issue is simply getting the database engine deployed and configured. One might add purchasing to the list as well as getting a licensed copy can be challenging in some companies. An obvious workaround is to use an existing database engine. The Registry serves as an excellent database for configuration information. The Event Logging system of windows is an excellent database for logging. Another common workaround is to use flat text files or xml files. You will still need a database engine, it just may not be apparent because you will be writing it in your program.
The next issue is getting the initial database schema in place. With a traditional engine like SQL Server this is challenging. The best solution is to use DataDude (also known at Microsoft Team System For Database Professionals). In the case of using built in engines like the Registry and Event Logging system the schema is in part dictated by the system and in part created as part of your install. The current setup project that Visual Studio creates makes Registry and Event Logging easy to maintain. In the case of flat text files or xml files, the schema is part of the file. Again the unseen trade off is you will be expending some effort in your code enforcing the schema.
The final deployment issue is getting the initial data in place. If you are not using the DataDude by now, you will find your database deployment has reared up and become a project unto itself. In the case of the Registry and Event Logging the initial values are created at the same time as schema is installed. And in the case of the flat text files or xml files, it is part of the file.
When looking across these options, it is easy to see that the flat text files or xml files present the easy path. The downside will occur later when the data must be shared with other programs, or performance issues arise. So the hard thing to do, but the right thing from an architecture view, is to force configuration information to be stored in the Registry, logging must be stored in the Event Logging system. And for other data, a database engine must be deployed and used.
One issue is simply getting the database engine deployed and configured. One might add purchasing to the list as well as getting a licensed copy can be challenging in some companies. An obvious workaround is to use an existing database engine. The Registry serves as an excellent database for configuration information. The Event Logging system of windows is an excellent database for logging. Another common workaround is to use flat text files or xml files. You will still need a database engine, it just may not be apparent because you will be writing it in your program.
The next issue is getting the initial database schema in place. With a traditional engine like SQL Server this is challenging. The best solution is to use DataDude (also known at Microsoft Team System For Database Professionals). In the case of using built in engines like the Registry and Event Logging system the schema is in part dictated by the system and in part created as part of your install. The current setup project that Visual Studio creates makes Registry and Event Logging easy to maintain. In the case of flat text files or xml files, the schema is part of the file. Again the unseen trade off is you will be expending some effort in your code enforcing the schema.
The final deployment issue is getting the initial data in place. If you are not using the DataDude by now, you will find your database deployment has reared up and become a project unto itself. In the case of the Registry and Event Logging the initial values are created at the same time as schema is installed. And in the case of the flat text files or xml files, it is part of the file.
When looking across these options, it is easy to see that the flat text files or xml files present the easy path. The downside will occur later when the data must be shared with other programs, or performance issues arise. So the hard thing to do, but the right thing from an architecture view, is to force configuration information to be stored in the Registry, logging must be stored in the Event Logging system. And for other data, a database engine must be deployed and used.
Monday, July 28, 2008
First Look At Cuil
Taking a quick First Look at the new search engine Cuil.
On the surface it would appear to return more results but when looking at quoted phrases it does something unexpected. Quite often Cuil fails to find the quoted phrase. This is disappointing because it is often the way I track down what some obscure cryptic error message means and how I should resolve it.
The increase in research results also does not hold up in searching for obscure terms. In fact for the obscure "Corpen Source" Cuil currently finds nothing. Google on the other hand finds plenty.
Quality of results is a little bit subjective but Cuil appears to have the edge here. Although it may just be the way Cuil presents the results in a panel fashion together with an image that may be the advantage. Either way, Cuil has marginally better results or a much improved layout.
On the surface it would appear to return more results but when looking at quoted phrases it does something unexpected. Quite often Cuil fails to find the quoted phrase. This is disappointing because it is often the way I track down what some obscure cryptic error message means and how I should resolve it.
The increase in research results also does not hold up in searching for obscure terms. In fact for the obscure "Corpen Source" Cuil currently finds nothing. Google on the other hand finds plenty.
Quality of results is a little bit subjective but Cuil appears to have the edge here. Although it may just be the way Cuil presents the results in a panel fashion together with an image that may be the advantage. Either way, Cuil has marginally better results or a much improved layout.
Sunday, July 27, 2008
Virtual Machine Sprawl
I've stopped using Virtual Machines because they are too useful. Kind of like Yogi saying of a restaurant, nobody goes there anymore because it is too crowded.
Actually I have just reached limit of the number of Virtual Machines I can track and have stopped creating and using additional virtual machines.
So Virtual Machines have crossed over the point where their own success is the problem. This problem has picked up the name Virtual Machine Sprawl. The sprawl problem creates four problems; space, providence, version control and restoration or setup speed.
Each virtual machine takes megs of space in the most compact form and in most cases after a few software installs they are up to gigs of space. I have found I need VMs for several OSes and for each OS I need a range of software installed and not installed and combinations in between. So before I know it I am up to 100s of gigs of space needed.
Providence refers to the prior history of the VM. Wear refers to this as the Genetic Makeup of the Virtual Machine. What is important here is not just what is installed but often the order it is installed. Every ASP.NET programmer is now familiar with the slight difference between installing IIS first then Visual Studio and installing Visual Studio first and then IIS.
Just like code there must be some mechanism for keeping original untouched copies of the machines. Unlike code, nearly everything you do with a virtual machine starts to change it. A primitive solution is to keep a directory full of copies. Unfortunately this instantly doubles the space requirements and there is nothing to prevent the machines being opened and thus spoiled.
Assuming you have found mechanism to track providence and another to track version you will still need to throw away your current copy and restore it from version control. As gigs are involved, the copying can take a chunk of time.
Actually I have just reached limit of the number of Virtual Machines I can track and have stopped creating and using additional virtual machines.
So Virtual Machines have crossed over the point where their own success is the problem. This problem has picked up the name Virtual Machine Sprawl. The sprawl problem creates four problems; space, providence, version control and restoration or setup speed.
Each virtual machine takes megs of space in the most compact form and in most cases after a few software installs they are up to gigs of space. I have found I need VMs for several OSes and for each OS I need a range of software installed and not installed and combinations in between. So before I know it I am up to 100s of gigs of space needed.
Providence refers to the prior history of the VM. Wear refers to this as the Genetic Makeup of the Virtual Machine. What is important here is not just what is installed but often the order it is installed. Every ASP.NET programmer is now familiar with the slight difference between installing IIS first then Visual Studio and installing Visual Studio first and then IIS.
Just like code there must be some mechanism for keeping original untouched copies of the machines. Unlike code, nearly everything you do with a virtual machine starts to change it. A primitive solution is to keep a directory full of copies. Unfortunately this instantly doubles the space requirements and there is nothing to prevent the machines being opened and thus spoiled.
Assuming you have found mechanism to track providence and another to track version you will still need to throw away your current copy and restore it from version control. As gigs are involved, the copying can take a chunk of time.
Saturday, July 26, 2008
C++ Hard To Do Security Right Easy To Do Wrong
Whenever possible you should make it easy to do the right thing and hard to do the wrong thing.
From a security point of view C++ may be broken simply because this dynamic is not only missing but reversed.
Take the function "strcpy". It is part of the standard library because C++ lacks a string class and thus it is commonly used. This function comes to mind because I added a huge chunk of existing code to my project. The code base liberally used "strcpy". Now in the "hard to do wrong" fashion the compiler warned on dozens of these and other security obsolete functions.
The security based warnings indicated in good "easy to do right" fashion that one should use "strncpy". The problem is that it often hard to determine the size of string at compile time, which the "n" in "strncpy" requires.
So you can see my dilemma either I retrofit size checking code in all of this imported code or live with the numerous security warnings and the reality they represent in terms of security holes.
Two recommendations from the community raised more concerns than comfort. One was to disable the warning. One poster included the amusing joke that starts with "Doctor it hurts when I do this.." Another disturbing recommendation was to replace the function call to "strcpy" with a hand coded replacement that had the same Stack Overflow problem.
So the effect was the practitioners in this space did not do right and in fact did wrong. Why? Because the language C++ makes it easy to do wrong. In this case the direct memory access. This is because it is hard to do right due to the lack of a standard string class that manages the memory access.
From a security point of view C++ may be broken simply because this dynamic is not only missing but reversed.
Take the function "strcpy". It is part of the standard library because C++ lacks a string class and thus it is commonly used. This function comes to mind because I added a huge chunk of existing code to my project. The code base liberally used "strcpy". Now in the "hard to do wrong" fashion the compiler warned on dozens of these and other security obsolete functions.
The security based warnings indicated in good "easy to do right" fashion that one should use "strncpy". The problem is that it often hard to determine the size of string at compile time, which the "n" in "strncpy" requires.
So you can see my dilemma either I retrofit size checking code in all of this imported code or live with the numerous security warnings and the reality they represent in terms of security holes.
Two recommendations from the community raised more concerns than comfort. One was to disable the warning. One poster included the amusing joke that starts with "Doctor it hurts when I do this.." Another disturbing recommendation was to replace the function call to "strcpy" with a hand coded replacement that had the same Stack Overflow problem.
So the effect was the practitioners in this space did not do right and in fact did wrong. Why? Because the language C++ makes it easy to do wrong. In this case the direct memory access. This is because it is hard to do right due to the lack of a standard string class that manages the memory access.
Friday, July 25, 2008
XML Literals As Database
Deploying the database has bedeviled development.
Data store and Engine are both issues. MSDE and SQL Express both represented attempts at getting an engine and data store on the machine. They worked well but presence of other applications using MSDE or SQL Express could complicate the deployment.
Standalone XML files, which is common for configuration, is a viable way to solve deploying the data store. Dot Net Framework embraced this common problem and a common solution now involves shipping an XML file to server as the initial data store.
With the XML Literals now part of VB.NET a better solution is possible. And the defect of using a separate language may even serve a purpose. On the one hand the XML literals are nothing more than the equivalent of the standalone files. But since they will be compiled into the executable and this will both create and hide access components the result will be faster and more reliable.
As to the language issue, this feature is only available in VB.Net. So to use this strategy from C# you would need to have a separate executable to house the VB.Net assembly dedicated to the XML Literal. But you could look at this defect as a feature in that it would encourage the separation of concerns.
Data store and Engine are both issues. MSDE and SQL Express both represented attempts at getting an engine and data store on the machine. They worked well but presence of other applications using MSDE or SQL Express could complicate the deployment.
Standalone XML files, which is common for configuration, is a viable way to solve deploying the data store. Dot Net Framework embraced this common problem and a common solution now involves shipping an XML file to server as the initial data store.
With the XML Literals now part of VB.NET a better solution is possible. And the defect of using a separate language may even serve a purpose. On the one hand the XML literals are nothing more than the equivalent of the standalone files. But since they will be compiled into the executable and this will both create and hide access components the result will be faster and more reliable.
As to the language issue, this feature is only available in VB.Net. So to use this strategy from C# you would need to have a separate executable to house the VB.Net assembly dedicated to the XML Literal. But you could look at this defect as a feature in that it would encourage the separation of concerns.
Thursday, July 24, 2008
Does Security Make C++ Obsolete
Stephen Gould said every species is extinct, they just do not know it.
From a security point of view C++ may be obsolete and we just do not know it yet. Increasing C++ is justified based on performance factors and legacy code. The performance increase that still remains is due primarily to the direct access to memory. This is when comparing to a language that handles memory management like Java or C# or VB.Net.
The security implications of direct memory access becomes apparent when examining lists of top security threats. At the top of the list are Buffer Overflows and Stack Overflows. Both are possible only because of direct memory access.
Since C# is memory managed except when you explicitly tell it not to be, you could say that it is "Secure By Default". This is in contrast to C++ which is "Unsecure By Default."
From a security point of view C++ may be obsolete and we just do not know it yet. Increasing C++ is justified based on performance factors and legacy code. The performance increase that still remains is due primarily to the direct access to memory. This is when comparing to a language that handles memory management like Java or C# or VB.Net.
The security implications of direct memory access becomes apparent when examining lists of top security threats. At the top of the list are Buffer Overflows and Stack Overflows. Both are possible only because of direct memory access.
Since C# is memory managed except when you explicitly tell it not to be, you could say that it is "Secure By Default". This is in contrast to C++ which is "Unsecure By Default."
Wednesday, July 23, 2008
Testing for Endianess
A colleague is studying for a Microsoft Interview.
One of the questions is to write code to test for Endian.
The answer Microsoft likes involves bit twiddling, but one wonders why they would not prefer calling their own framework:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("BitConverter.IsLittleEndian " + BitConverter.IsLittleEndian.ToString());
Console.ReadLine();
}
}
}
One of the questions is to write code to test for Endian.
The answer Microsoft likes involves bit twiddling, but one wonders why they would not prefer calling their own framework:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("BitConverter.IsLittleEndian " + BitConverter.IsLittleEndian.ToString());
Console.ReadLine();
}
}
}
Tuesday, July 22, 2008
Five Things That Come First
In reading "Writing Secure Code" I was heartened to find the author state "Security is a top priority". The statement as whole is not surprising for the book but the use of "a" as in "a top priority" instead of "the" as in "the top priority" was the comforting part.
Reading Roger Session's blog on code complexity, Roger implies that complexity is more important than security. As in if the code is complex it can never be secured. So that would imply Complexity (or reducing it comes first).
The Test Driven Development movement preaches Test First. It should be noted, code is not testable by default. You will always need to do something to make it testable.
Any book on Scalable Architectures will tell you, you must design from the start for scalability. So add Scalability to the list of things to be done before anything else.
I myself have learned the hard way to do the install first. But having an installer does not guarantee that your software will be deployable. So but Deployable on the list as well.
Thus you end up with Five Things That Come First before you even write your first line of code.
Security
Scalability
Testable
Deployable
Complexity
Monday, July 21, 2008
ASP.NET Security Terms
ASP.NET Security Terms
Authentication - Determining identity.
Authorization - Determining the rights and restrictions associated with an identity.
Confidentiality - Ensuring data is accessible to only those authorized.
Custom Authentication - When the authentication is implemented without using one the standard authentications; Windows, Forms or Passport
Forms Based Authentication -
Impersonation - Executing code in the context of another identity.
Integrity - Ensuring data has not been changed in an unauthorized manner.
Passport Based Authentication - Authentication is handle by Passport
Role Based Authorization - Authorization that uses Roles or Groups as intermediaries in assigning rights and restrictions.
Windows Based Authentication - Credentials are verified against windows accounts. Where possible the windows integrated log in form is used.
Authentication - Determining identity.
Authorization - Determining the rights and restrictions associated with an identity.
Confidentiality - Ensuring data is accessible to only those authorized.
Custom Authentication - When the authentication is implemented without using one the standard authentications; Windows, Forms or Passport
Forms Based Authentication -
Impersonation - Executing code in the context of another identity.
Integrity - Ensuring data has not been changed in an unauthorized manner.
Passport Based Authentication - Authentication is handle by Passport
Role Based Authorization - Authorization that uses Roles or Groups as intermediaries in assigning rights and restrictions.
Windows Based Authentication - Credentials are verified against windows accounts. Where possible the windows integrated log in form is used.
Sunday, July 20, 2008
Corpen Source
Clopen Source refers to Open Source projects that have adopted practices that Close off uses or rights. There is a special category of Clopen Source that feature a Corporate Entity like Sun, Microsoft, Novell or any large company, supporting the Open Source software. This blending of Corporate and Open Source software should be labeled as such as Corpen Source.
Novell is currently the corporate patron of the Mono project. Mono could be summarized as Dot Net Framework Everywhere. That is the making the Dot Net Framework available on non Windows OS but it will also be available on Windows. If Mono remains successful, this cross platform capacity would make it preferable to Microsoft's version. So one can see how Novell interest in this project and as the corporate sugar daddy it is clear Novell will call the shots. As such, Mono is a Corpen Source project.
Firefox which is spun out of Mozilla is a Corpen project of Mozilla. But in addition to this Google provides significant resources in exchange for access. The integration of Google search and antiphishing consolidates Firefox as a Clopen Source project.
In addition to Corpen Source there are Corpen Standards projects. Microsoft submitted C# before ISO and ECMA, but as Microsoft provides all the resources it is clear C# is a Clopen Standard. Sun started to submit Java to ISO and ECMA but withdrew and released large portions under the GNU GPL instead. No doubt this was an attempt to get Java accepted as an Open Standard while retaining control. Having failed this they made Java into a Clopen Source project.
Novell is currently the corporate patron of the Mono project. Mono could be summarized as Dot Net Framework Everywhere. That is the making the Dot Net Framework available on non Windows OS but it will also be available on Windows. If Mono remains successful, this cross platform capacity would make it preferable to Microsoft's version. So one can see how Novell interest in this project and as the corporate sugar daddy it is clear Novell will call the shots. As such, Mono is a Corpen Source project.
Firefox which is spun out of Mozilla is a Corpen project of Mozilla. But in addition to this Google provides significant resources in exchange for access. The integration of Google search and antiphishing consolidates Firefox as a Clopen Source project.
In addition to Corpen Source there are Corpen Standards projects. Microsoft submitted C# before ISO and ECMA, but as Microsoft provides all the resources it is clear C# is a Clopen Standard. Sun started to submit Java to ISO and ECMA but withdrew and released large portions under the GNU GPL instead. No doubt this was an attempt to get Java accepted as an Open Standard while retaining control. Having failed this they made Java into a Clopen Source project.
Saturday, July 19, 2008
Clopen Source
The promise of Open Source was Free Software.
Open Source takes it's name from the practice that the source code should be open in all senses. It should be Open for Inspection. It should be Open for Contributions and It should be Open for Repurposing for Alternate Uses.
But like the first communes and every commune since, it is broken up by questions of who owns what and who should decide. One piece of property that no open source project will surrender is their trademark. Trademark becomes the camels nose under the tent. Here the camel is asserting that the software is Closed for some purposes.
More of the Closed camel follows because there must be some entity to govern both the use of the property and development of the software. If no one became rich or famous, a minimal platonic democracy could have formed and it would somehow work. Now everyone has an eye on cashing in big on their Open Source project. Often the projects license have terms that allow the owners to take back the software.
Open Source takes it's name from the practice that the source code should be open in all senses. It should be Open for Inspection. It should be Open for Contributions and It should be Open for Repurposing for Alternate Uses.
But like the first communes and every commune since, it is broken up by questions of who owns what and who should decide. One piece of property that no open source project will surrender is their trademark. Trademark becomes the camels nose under the tent. Here the camel is asserting that the software is Closed for some purposes.
More of the Closed camel follows because there must be some entity to govern both the use of the property and development of the software. If no one became rich or famous, a minimal platonic democracy could have formed and it would somehow work. Now everyone has an eye on cashing in big on their Open Source project. Often the projects license have terms that allow the owners to take back the software.
The GNU License is another common closing. Because this license grows virally you must always be worried that the free software you use will ultimately cost you your software.
A minor variation of open source software closing are projects that require extensive signing over of rights. Fortunately the irritation factor has caused these project to wither.
The takeaway from all of this is every Open Source project has some significant Closed aspects to it. As such we should borrow a term from mathematics and label projects that are significantly closed as Clopen Source. And projects which use the GNU License or have take back provision should present themselves as Clopen Source projects.
Friday, July 18, 2008
Open Source's Infinite Budget: Part 2 Your Company
Open Source has an infinite budget
As I discussed in Part 1 The Community, the open source community is not the source of this infinite budget. In fact the Open Source projects are overrun with bugs and security breaches and as such are turning to various Clopen models to generate revenue. Most of the Clopen Source modes are failing. (The notable exceptions are using a variant of Clopen Source which can be called Corpen Source which I will address in another post.) So if the infinite budget is not in the community where is it?
If you have allowed a free reign of open source in your company then it is coming from you. And it is being spent in a way that should alarm you.
Suppose your company allows the use of any and all open source tools. To the developer this is functionally the equivalent of an infinite budget for open source tools and software.
Whenever the developer wants a tool it's purchase is automatically approved because the price "free" does not reduce any budget.
He then can start using the tool and all is well.
Provided of course that it stands alone and has no bugs or security problems. Oh and provided of course that he does not need to learn how to use it. But if it needs to be integrated or bugs need to fixed then the budget that pays for it is hidden from management.
The developer will be spending hours integrating or fixing or working around bugs. These hours come out of the finite number of developer hours available to you. Note there is no check or limit on how much effort will be spent on supporting open source in your company, as such the budget for open source that you are paying is infinite.
So what is the moral? Never use open source software?
No, the answer is harder than that. What is called for here is management. Management means monitoring and making some hard decisions based on facts. Some open source software, NUnit would be may favorite example, is almost defect free and can be easily used with little integration or learning ramp up time.
But keep an eye on these, even if you stick to solid open source software, the integration costs increase at a factorial rate as the number of components increase.
There will come a time when you should opt to use a development stack and pay a flat fee instead. MSDN is a great example. For a few hundred dollars a developer (partner pricing) you can get access to all the software needed and at the same time the integration costs disappear.
As I discussed in Part 1 The Community, the open source community is not the source of this infinite budget. In fact the Open Source projects are overrun with bugs and security breaches and as such are turning to various Clopen models to generate revenue. Most of the Clopen Source modes are failing. (The notable exceptions are using a variant of Clopen Source which can be called Corpen Source which I will address in another post.) So if the infinite budget is not in the community where is it?
If you have allowed a free reign of open source in your company then it is coming from you. And it is being spent in a way that should alarm you.
Suppose your company allows the use of any and all open source tools. To the developer this is functionally the equivalent of an infinite budget for open source tools and software.
Whenever the developer wants a tool it's purchase is automatically approved because the price "free" does not reduce any budget.
He then can start using the tool and all is well.
Provided of course that it stands alone and has no bugs or security problems. Oh and provided of course that he does not need to learn how to use it. But if it needs to be integrated or bugs need to fixed then the budget that pays for it is hidden from management.
The developer will be spending hours integrating or fixing or working around bugs. These hours come out of the finite number of developer hours available to you. Note there is no check or limit on how much effort will be spent on supporting open source in your company, as such the budget for open source that you are paying is infinite.
So what is the moral? Never use open source software?
No, the answer is harder than that. What is called for here is management. Management means monitoring and making some hard decisions based on facts. Some open source software, NUnit would be may favorite example, is almost defect free and can be easily used with little integration or learning ramp up time.
But keep an eye on these, even if you stick to solid open source software, the integration costs increase at a factorial rate as the number of components increase.
There will come a time when you should opt to use a development stack and pay a flat fee instead. MSDN is a great example. For a few hundred dollars a developer (partner pricing) you can get access to all the software needed and at the same time the integration costs disappear.
Thursday, July 17, 2008
Backing Down A Bug
So a bug is found in production.
In spite of your following all the best practices.
You had separate environments for Development, Integration, QA (testing), UAT and Production.
You have been doing versioned releases and following your documented change control procedures.
You had a QA staff that did it's best to test for and find all bugs.
You have three levels of help desk or technical support.
And in spite of this a bug made it all the way out to production and it must be fixed. And the business side of the house is flipping out and the pressure is on. Fix the bug now!!
How you handle this will determine if your company grows and gets a tiny bit better. Or should you fail, you the company will plant the seeds of disruptive behavior that will haunt you for the rest of your tenure.
You must avoid the temptation to storm in and take things over. You need to Back This Bug Down From Production with the care you would back a jumper from a ledge.
First make sure that the help desk or technical support was engaged. If not, engage them. Use this as learning opportunity for the support staff to learn how to mitigate or work around bugs in production. Should you find a work around, you must insist to the suits that it is over. A work around has been found. The work around is in place. Both the bug and issue (the issue is how the bug made it to production) are being researched and will fixed in later release. End of Story. Do not be stampeded on this.
Now chances are good that a work around is not immediately found. In this case, the backing down starts. QA must take a role here. At this point QA has tested the application and their job is to get the bug reproduced in the QA environment. Again, you must resist the desire to jump in and take over. QA has an important role in defining the bug. If QA can reproduce the bug in the QA environment, you should then be able to use this information to reproduce the bug in the Development environment. When you have fixed bug, QA will now be in a position to test the fix. This would not be possible if you had ripped control away from Tech Support or QA.
But this is not the end of the story. There is still the open issue of how the bug survived your processes. Inevitably something is missing in terms of testing or the processes were not followed. Fixing this issue will prevent future bugs.
In spite of your following all the best practices.
You had separate environments for Development, Integration, QA (testing), UAT and Production.
You have been doing versioned releases and following your documented change control procedures.
You had a QA staff that did it's best to test for and find all bugs.
You have three levels of help desk or technical support.
And in spite of this a bug made it all the way out to production and it must be fixed. And the business side of the house is flipping out and the pressure is on. Fix the bug now!!
How you handle this will determine if your company grows and gets a tiny bit better. Or should you fail, you the company will plant the seeds of disruptive behavior that will haunt you for the rest of your tenure.
You must avoid the temptation to storm in and take things over. You need to Back This Bug Down From Production with the care you would back a jumper from a ledge.
First make sure that the help desk or technical support was engaged. If not, engage them. Use this as learning opportunity for the support staff to learn how to mitigate or work around bugs in production. Should you find a work around, you must insist to the suits that it is over. A work around has been found. The work around is in place. Both the bug and issue (the issue is how the bug made it to production) are being researched and will fixed in later release. End of Story. Do not be stampeded on this.
Now chances are good that a work around is not immediately found. In this case, the backing down starts. QA must take a role here. At this point QA has tested the application and their job is to get the bug reproduced in the QA environment. Again, you must resist the desire to jump in and take over. QA has an important role in defining the bug. If QA can reproduce the bug in the QA environment, you should then be able to use this information to reproduce the bug in the Development environment. When you have fixed bug, QA will now be in a position to test the fix. This would not be possible if you had ripped control away from Tech Support or QA.
But this is not the end of the story. There is still the open issue of how the bug survived your processes. Inevitably something is missing in terms of testing or the processes were not followed. Fixing this issue will prevent future bugs.
Wednesday, July 16, 2008
Open Source's Infinite Budget: Part 1 The Community
Functionally Open Source has an unlimited budget.
Open Source promoters rave about the legion of programmers that stand poised to squash any bug that emerges and the other legion diligently adding features and functionality that the suits would never allow in a corporate run development and yet another legion that will repair any security breach discovered. It would appear that there is a bottomless pit development resources for any Open Source project.
But despite this, Open Source projects are plagued with bugs and security failures. Boosterism on the part of the Open Source believers and antipathy (the contempt and aversion variety) on the part of Open Source skeptics has resulted in these defects receiving little coverage.
So let me refresh your memory with a few salient recent developments. In a head to head security test of the LAMP (Linux Apache MySql PHP) stack versus the Microsoft stack, the LAMP stack was breached first. Linus Torvalds has been quoted "Even by the most *stringent* reasonable rules, we add a new bug every four days." Linus is pleading for us to look past the bugs because of all the features they are adding. What he and other Open Projects are lacking is resources devoted to QA. But even if they had adequate QA there is an additional lack of desire in developers working for free to fix bugs. They would much rather implement some bright shiny object.
This lack has on the one hand caused Linus to threaten to halt all new development on the kernel so that the bugs must be fixed. And in the rest of the community we have seen numerous experiments in Clopening the software. (Clopen is a term borrowed from the mathematicians, it is possible for things like sets to be both closed and open in math, when this happens they joke that the set is clopen). The idea behind Clopening the Software is this will give the projects resources to get a handle on Architecture and QA as well as means of providing the maintenance to fix those bugs no one wants to work. Often the Clopen occurs by offering privileged access for those who pay a premium. The software projects are surprised to learn that there are few takers and in return for the small amount of revenue they want quite a bit of control.
Which leaves one to conclude that Open Source's Infinite Budget does not come from the community. In Part 2 Your Company, we will find the ugly truth.
Open Source promoters rave about the legion of programmers that stand poised to squash any bug that emerges and the other legion diligently adding features and functionality that the suits would never allow in a corporate run development and yet another legion that will repair any security breach discovered. It would appear that there is a bottomless pit development resources for any Open Source project.
But despite this, Open Source projects are plagued with bugs and security failures. Boosterism on the part of the Open Source believers and antipathy (the contempt and aversion variety) on the part of Open Source skeptics has resulted in these defects receiving little coverage.
So let me refresh your memory with a few salient recent developments. In a head to head security test of the LAMP (Linux Apache MySql PHP) stack versus the Microsoft stack, the LAMP stack was breached first. Linus Torvalds has been quoted "Even by the most *stringent* reasonable rules, we add a new bug every four days." Linus is pleading for us to look past the bugs because of all the features they are adding. What he and other Open Projects are lacking is resources devoted to QA. But even if they had adequate QA there is an additional lack of desire in developers working for free to fix bugs. They would much rather implement some bright shiny object.
This lack has on the one hand caused Linus to threaten to halt all new development on the kernel so that the bugs must be fixed. And in the rest of the community we have seen numerous experiments in Clopening the software. (Clopen is a term borrowed from the mathematicians, it is possible for things like sets to be both closed and open in math, when this happens they joke that the set is clopen). The idea behind Clopening the Software is this will give the projects resources to get a handle on Architecture and QA as well as means of providing the maintenance to fix those bugs no one wants to work. Often the Clopen occurs by offering privileged access for those who pay a premium. The software projects are surprised to learn that there are few takers and in return for the small amount of revenue they want quite a bit of control.
Which leaves one to conclude that Open Source's Infinite Budget does not come from the community. In Part 2 Your Company, we will find the ugly truth.
Tuesday, July 15, 2008
C# Naming Conventions
No one C# naming convention has dominated development.
A few of the major forms are All-caps, Camel Casing, C-casing, Pascal Casing and Hungarian.
In fact Microsoft recommends a mixture of these in development. Although it is clear that at this point Hungarian and All-caps are out of favor with most developers.
All-caps is the upper casing of every letter or using all capital letters. This holds on in the naming of constants or objects that are considered non moving.
Camel Casing has compound names using capital letters for the first letter and lower case for the rest with the exception of the very first letter. So if a variable is for a "file handle" it would be named "fileHandle". The memory device for this is to think the camel has the high point in the middle.
C-casing which is also called Underscore separation has the compound names joined with underscores; so "file handle" would be "file_handle".
Pascal Casing which takes it's name from the language Pascal where it became dominant has compound names using capital first letters for each part; as in "file handle"becomes "FileHandle".
Hungarian which became dominant in Visual C++ and Visual Basic and is in disfavor now is harder to formulate because there are many variations. It is my belief it has died of the weight of all the variations. Some key features of all variations is the prefixing of a single lowercase letter to indicate type. If the "file handle" was of type Handle it would be "hFile". Another common feature is to prefix this with "m_" to indicate class level scope.
A few of the major forms are All-caps, Camel Casing, C-casing, Pascal Casing and Hungarian.
In fact Microsoft recommends a mixture of these in development. Although it is clear that at this point Hungarian and All-caps are out of favor with most developers.
All-caps is the upper casing of every letter or using all capital letters. This holds on in the naming of constants or objects that are considered non moving.
Camel Casing has compound names using capital letters for the first letter and lower case for the rest with the exception of the very first letter. So if a variable is for a "file handle" it would be named "fileHandle". The memory device for this is to think the camel has the high point in the middle.
C-casing which is also called Underscore separation has the compound names joined with underscores; so "file handle" would be "file_handle".
Pascal Casing which takes it's name from the language Pascal where it became dominant has compound names using capital first letters for each part; as in "file handle"becomes "FileHandle".
Hungarian which became dominant in Visual C++ and Visual Basic and is in disfavor now is harder to formulate because there are many variations. It is my belief it has died of the weight of all the variations. Some key features of all variations is the prefixing of a single lowercase letter to indicate type. If the "file handle" was of type Handle it would be "hFile". Another common feature is to prefix this with "m_" to indicate class level scope.
Monday, July 14, 2008
The meaning of .vssscc .vspscc and .suo files.
The meaning of .vssscc .vspscc and .suo files.
Should .vssscc, .vspscc and .suo files be added to source Control?
The .vssscc and .vspscc should be added to source control and the .suo file should be excluded.
What is the easiest way to do this?
Use the "Add solution to source control" menu item.
What are these files?
The .vssscc file is referred to as the solution hint file. It has entries to help keep the solution in sync with source control.
The .vspscc file is referred to as the project hint file and it also helps to keep the project in sync with source control.
The .suo file stores user specific setting for Visual Studio. Since different team member can vary these settings it should not be checked in.
Should .vssscc, .vspscc and .suo files be added to source Control?
The .vssscc and .vspscc should be added to source control and the .suo file should be excluded.
What is the easiest way to do this?
Use the "Add solution to source control" menu item.
What are these files?
The .vssscc file is referred to as the solution hint file. It has entries to help keep the solution in sync with source control.
The .vspscc file is referred to as the project hint file and it also helps to keep the project in sync with source control.
The .suo file stores user specific setting for Visual Studio. Since different team member can vary these settings it should not be checked in.
Sunday, July 13, 2008
Fixing: Active Directory, Adding a Group to a Group
Problem description:
In some implementations of Active Directory you cannot Add a Group to a Group.
This is new functionality so to get this to work you will need to select the menu option "raise functionality".
In some implementations of Active Directory you cannot Add a Group to a Group.
This is new functionality so to get this to work you will need to select the menu option "raise functionality".
C Sharp Interview Questions: Modifiers
Interview Quesions involving class and method modifiers.
1. What are the features of an abstract class?
Answer: It cannot be instantiated.It can contain abstrast methods and accessors.
2. When an non-abstract class derives from an abstract class with abstract methods or accessors what must it do?
Answer: It must provide implementations for all abstract methods and accessors.
3. What is an abstract method?
Answer: Implicitly it is a virtual method.Permitted only in abstract classes.It has no body.
4. Why are abstract methods not permitted in non-abstract classes?
Answer: Abstract methods have no implementation, which would be required in a concrete class.
5. When a field or local variable is marked const what does it change?
Answer: The value cannot change. It can only be initialized at declaration.
6. How is override used?
Answer: It is used to modify a method, property or indexer to change the implementation.
7. When a field is marked readonly what does it change?
Answer: The value can only be set in the constructor during initialization.
8. In terms of runtime and compile time, compare const and readonly.
Answer. const is compile time and readonly is runtime.
9. What is a sealed class?
Answer: The class cannot be derived by another class.
10. How does static change fields and methods?
Answer: They become global and belong to the type instead of the instance.
11. What is a virtual method?Answer: It is a method that implementation can be changed in a derived class by using the override keyword.
12. Why is modifiying a class with both abstract and sealed an error?
Answer: An abstract class cannot be instantiated
1. What are the features of an abstract class?
Answer: It cannot be instantiated.It can contain abstrast methods and accessors.
2. When an non-abstract class derives from an abstract class with abstract methods or accessors what must it do?
Answer: It must provide implementations for all abstract methods and accessors.
3. What is an abstract method?
Answer: Implicitly it is a virtual method.Permitted only in abstract classes.It has no body.
4. Why are abstract methods not permitted in non-abstract classes?
Answer: Abstract methods have no implementation, which would be required in a concrete class.
5. When a field or local variable is marked const what does it change?
Answer: The value cannot change. It can only be initialized at declaration.
6. How is override used?
Answer: It is used to modify a method, property or indexer to change the implementation.
7. When a field is marked readonly what does it change?
Answer: The value can only be set in the constructor during initialization.
8. In terms of runtime and compile time, compare const and readonly.
Answer. const is compile time and readonly is runtime.
9. What is a sealed class?
Answer: The class cannot be derived by another class.
10. How does static change fields and methods?
Answer: They become global and belong to the type instead of the instance.
11. What is a virtual method?Answer: It is a method that implementation can be changed in a derived class by using the override keyword.
12. Why is modifiying a class with both abstract and sealed an error?
Answer: An abstract class cannot be instantiated
Saturday, July 12, 2008
Visual Studio: Hot Keys: Windows
Most of the Hot Key chords for windows start with Ctrl W.
The ones that do not close windows or are data related.
Ctrl W A
Command Window
Ctrl W C
Class View
Ctrl W D
Code Definition Window
Ctrl W E
Error List
Ctrl W L
Server Explorer
Ctrl W O
Output
Ctrl W P
Properties
Ctrl W S
Solution Explorer
Ctrl W T
Task List
Ctrl W X
Toolbox
Ctrl Esc
Close Window
Ctrl Alt D
Data Sources
Ctrl F4
Close current tab
Ctrl Tab
IDE Navigator, first document (next document)
The ones that do not close windows or are data related.
Ctrl W A
Command Window
Ctrl W C
Class View
Ctrl W D
Code Definition Window
Ctrl W E
Error List
Ctrl W L
Server Explorer
Ctrl W O
Output
Ctrl W P
Properties
Ctrl W S
Solution Explorer
Ctrl W T
Task List
Ctrl W X
Toolbox
Ctrl Esc
Close Window
Ctrl Alt D
Data Sources
Ctrl F4
Close current tab
Ctrl Tab
IDE Navigator, first document (next document)
Friday, July 11, 2008
C Sharp Interview Questions: Operators
Questions involving Operators.
1. When the division operator "/" is used with two integers what is result?
Answer: An integer division with the remainder discarded ( 16 / 5 is 3).
2. What is the operator "%"?
Answer: It returns the remainder from the division.
3. What are the operators "" and ""? How do the differ?
Answer:
Operator "" is the bitwise-or operator.
It accepts boolean operands and integer operands.
The second parameter is always evaluated.
For integer operatands the individual bit places are or'ed separately.
Operator "" is the condition-or operator.
If the first operand is true the second parameter will not be evaluated.
4. What are the operators "&" and "&&"? How do the differ?
Answer:
Operator "&" is the bitwise-and operator.
It accepts boolean operands and integer operands.
The second parameter is always evaluated.
For integer operands the individual bit places are and'ed separately.
Operator "&&" is the condition-and operator.
If the first operand is false the second parameter will not be evaluated.
5. What are the operators '>>' and '<<'? Which mathematical operations are similiar? Answer: Operator '>>' is the right shift operator (right bit shift). It is similar to dividing by a power of 2.
Operator '<<' is the left shift operator (left bit shift). It is similar to multiplying by a power of 2.
6. What are the operators '?:' and '??' ?
Answer:
Operator '?:' is the conditional operator and is used in a statement in the form:
(conditional expression) ? (expression 1) : (expression 2)
If the (conditional expression) evaluates to true then the result of (expression 1) is returned.
If the (conditional expression) evaluates to false then the result of (expression 2) is returned.
Operator '??' returns the left operand if the left operand is not null otherwise it returns the right operand.
1. When the division operator "/" is used with two integers what is result?
Answer: An integer division with the remainder discarded ( 16 / 5 is 3).
2. What is the operator "%"?
Answer: It returns the remainder from the division.
3. What are the operators "" and ""? How do the differ?
Answer:
Operator "" is the bitwise-or operator.
It accepts boolean operands and integer operands.
The second parameter is always evaluated.
For integer operatands the individual bit places are or'ed separately.
Operator "" is the condition-or operator.
If the first operand is true the second parameter will not be evaluated.
4. What are the operators "&" and "&&"? How do the differ?
Answer:
Operator "&" is the bitwise-and operator.
It accepts boolean operands and integer operands.
The second parameter is always evaluated.
For integer operands the individual bit places are and'ed separately.
Operator "&&" is the condition-and operator.
If the first operand is false the second parameter will not be evaluated.
5. What are the operators '>>' and '<<'? Which mathematical operations are similiar? Answer: Operator '>>' is the right shift operator (right bit shift). It is similar to dividing by a power of 2.
Operator '<<' is the left shift operator (left bit shift). It is similar to multiplying by a power of 2.
6. What are the operators '?:' and '??' ?
Answer:
Operator '?:' is the conditional operator and is used in a statement in the form:
(conditional expression) ? (expression 1) : (expression 2)
If the (conditional expression) evaluates to true then the result of (expression 1) is returned.
If the (conditional expression) evaluates to false then the result of (expression 2) is returned.
Operator '??' returns the left operand if the left operand is not null otherwise it returns the right operand.
Thursday, July 10, 2008
First look at Googles Protocol Buffer.
First look at Googles Protocol Buffer.
First the hype; Google wants you to think of Protocol Buffers as the New XML.
As such the list 5 reasons on the overview page for why Protocol Buffers have advantages over XML.
http://code.google.com/apis/protocolbuffers/docs/overview.html
1. Simpler
2. 3 to 10 times smaller
3. 20 to 100 times faster
4. less ambiguous
5. easier to program and generate data access classes
Two comments come to mind right off the bat.
Some of the performance gains come from poorly form xml design as such their are cases where the Protocol Buffer will be more than 10 time smaller and more than 100 times faster.
So it might condense things to say 3 times or more smaller and 20 times faster.
Lets look at the examples Google provides here is an xml snippet
John Doe
jdoe@example.com
And here is the thing which is NOT the protocol buffer
# Textual representation of a protocol buffer.
# This is *not* the binary format used on the wire.
person {
name: "John Doe"
email: "jdoe@example.com"
}
The 'Not' is important here because the protocol buffer is not stored in a human readable or text format.
It is stored as binary, which means human readability is gone.
No matter, but looking at the example it is hard to see how if I use a absurdly long name, how the XML would be three times larger than the Protocol Buffer.
In fact as I push it out to large lengths the two formats should have a ratio of sizes of about 1 to 1.
The faster is easy to see.
We will not be opening and closing a bunch of tags and the tags themselves have opening closing brackets that aid human comprehension but become dead weight repetitive.
But in the counter example used for size it is hard to see how the same example would not show a speed ratio between the formats of 2 to 1.
Now on the upside.
Clearly it is less ambiguous. If you have tried to make XML live up to its hype you know the ambiguous pitfalls.
The "easier to program and generate data access classes" is function of Protocol Buffers being more constrained in what they will support and what is legal.
History relives itself here, XML was the same "simplify to gain power" condensing of HTML.
Likewise HTML condensed SGML.
There is another fundamental divergence from XML. You could use XML without documenting the schema.
This was in classic software fashion the greatest strength in rapidly spreading XML because there were no rules.
And the greatest weakness in that there where no rules so we never were 100% sure what documents meant or if they were well formed or complete.
This is diffent in that Protocol Buffers are defined in "Protocol Buffer Message Definitions" stored in a ".proto" file.
These are similiar to XML's DTD or Schemas.
The difference is they are now required.
Again there is the history flashback, HTML did not require closing tags, XML did and that made all the difference.
First the hype; Google wants you to think of Protocol Buffers as the New XML.
As such the list 5 reasons on the overview page for why Protocol Buffers have advantages over XML.
http://code.google.com/apis/protocolbuffers/docs/overview.html
1. Simpler
2. 3 to 10 times smaller
3. 20 to 100 times faster
4. less ambiguous
5. easier to program and generate data access classes
Two comments come to mind right off the bat.
Some of the performance gains come from poorly form xml design as such their are cases where the Protocol Buffer will be more than 10 time smaller and more than 100 times faster.
So it might condense things to say 3 times or more smaller and 20 times faster.
Lets look at the examples Google provides here is an xml snippet
And here is the thing which is NOT the protocol buffer
# Textual representation of a protocol buffer.
# This is *not* the binary format used on the wire.
person {
name: "John Doe"
email: "jdoe@example.com"
}
The 'Not' is important here because the protocol buffer is not stored in a human readable or text format.
It is stored as binary, which means human readability is gone.
No matter, but looking at the example it is hard to see how if I use a absurdly long name, how the XML would be three times larger than the Protocol Buffer.
In fact as I push it out to large lengths the two formats should have a ratio of sizes of about 1 to 1.
The faster is easy to see.
We will not be opening and closing a bunch of tags and the tags themselves have opening closing brackets that aid human comprehension but become dead weight repetitive.
But in the counter example used for size it is hard to see how the same example would not show a speed ratio between the formats of 2 to 1.
Now on the upside.
Clearly it is less ambiguous. If you have tried to make XML live up to its hype you know the ambiguous pitfalls.
The "easier to program and generate data access classes" is function of Protocol Buffers being more constrained in what they will support and what is legal.
History relives itself here, XML was the same "simplify to gain power" condensing of HTML.
Likewise HTML condensed SGML.
There is another fundamental divergence from XML. You could use XML without documenting the schema.
This was in classic software fashion the greatest strength in rapidly spreading XML because there were no rules.
And the greatest weakness in that there where no rules so we never were 100% sure what documents meant or if they were well formed or complete.
This is diffent in that Protocol Buffers are defined in "Protocol Buffer Message Definitions" stored in a ".proto" file.
These are similiar to XML's DTD or Schemas.
The difference is they are now required.
Again there is the history flashback, HTML did not require closing tags, XML did and that made all the difference.
Wednesday, July 9, 2008
Obsolete's Key Role In Agile Software Development
There is one attribute that has a unique and powerful roll; Obsolete.
Here are four examples applications to the same function 'Funky'
1:
[Obsolete()]
void Funky(){...}
2:
[Obsolete("Use Freaky instead")]
void Funky(){...}
3:
[Obsolete("Use Freaky instead", false)]
void Funky(){...}
4:
[Obsolete("Use Freaky instead", true)]
void Funky(){...}
Starting with 1 you can use this attribute without any of the parameters. In this default mode it will generate a warning indicating the method is obsolete. Following the rule of "Making the Right thing Easy and the Wrong thing Hard" this should be avoided in favor of 2; Use the message string to explain what should be done instead.
Example 3 is equivalent to 2, the second parameter determines if the Obsolete attribute results in a warning (false, the default) or an error (true). It is rare that you will actually have this set to true (4) and checked in to source control, since that would break the build. But it does happen and it is a more elegant way of making "The Wrong thing Hard" than commenting out the obsolete code.
How you will use 4 is to explore the level of effort involved in changing code. In a typical "Drain A Swamp" effort; the code might not even compile from source control without error. After considerable effort you will get the errors out but be left with numerous warnings. This morass of warnings will hide the ones generated by Obsolete. So working with generate error set to true will provide a count of what is left and a road map of what to fix.
In Green Field efforts Obsolete provides a effective means of communication of intent between teams working on separate modules. It raises the flag that one team wants to change something but does not force another team to change immediately. Perhaps the second team needs to transform and obsolete some code as a result. On balance it allows for teams of programmers to behave in an agile manner.
But perhaps the best benefit of Obsolete is the knowledge that it is there and provides a way for a programmer to take back his mistakes. What is not stressed enough about Agile methodologies is that it is a safe way for programmers to make mistakes. This frees them to discover things that can never be known beforehand in a Command and Control Central Planning mode of development. By fearless experimentation and ruthless obsoleting programmers will flow past problems, discovering the easy way much like water finds the downward path to the sea.
Here are four examples applications to the same function 'Funky'
1:
[Obsolete()]
void Funky(){...}
2:
[Obsolete("Use Freaky instead")]
void Funky(){...}
3:
[Obsolete("Use Freaky instead", false)]
void Funky(){...}
4:
[Obsolete("Use Freaky instead", true)]
void Funky(){...}
Starting with 1 you can use this attribute without any of the parameters. In this default mode it will generate a warning indicating the method is obsolete. Following the rule of "Making the Right thing Easy and the Wrong thing Hard" this should be avoided in favor of 2; Use the message string to explain what should be done instead.
Example 3 is equivalent to 2, the second parameter determines if the Obsolete attribute results in a warning (false, the default) or an error (true). It is rare that you will actually have this set to true (4) and checked in to source control, since that would break the build. But it does happen and it is a more elegant way of making "The Wrong thing Hard" than commenting out the obsolete code.
How you will use 4 is to explore the level of effort involved in changing code. In a typical "Drain A Swamp" effort; the code might not even compile from source control without error. After considerable effort you will get the errors out but be left with numerous warnings. This morass of warnings will hide the ones generated by Obsolete. So working with generate error set to true will provide a count of what is left and a road map of what to fix.
In Green Field efforts Obsolete provides a effective means of communication of intent between teams working on separate modules. It raises the flag that one team wants to change something but does not force another team to change immediately. Perhaps the second team needs to transform and obsolete some code as a result. On balance it allows for teams of programmers to behave in an agile manner.
But perhaps the best benefit of Obsolete is the knowledge that it is there and provides a way for a programmer to take back his mistakes. What is not stressed enough about Agile methodologies is that it is a safe way for programmers to make mistakes. This frees them to discover things that can never be known beforehand in a Command and Control Central Planning mode of development. By fearless experimentation and ruthless obsoleting programmers will flow past problems, discovering the easy way much like water finds the downward path to the sea.
Tuesday, July 8, 2008
Visual Studio: Hot Keys: Solutions Projects Files
Ctrl Shift N
New project
Ctrl Shift O
Displays the Open Project dialog
Shift Alt C
Add New Item, with class as default
Shift Alt A
Add Existing Item
Ctrl Shift A
Add New Item, with file as default
Ctrl Alt Down Arrow
Displays list of all open documents
Ctrl O
Open File Dialog
New project
Ctrl Shift O
Displays the Open Project dialog
Shift Alt C
Add New Item, with class as default
Shift Alt A
Add Existing Item
Ctrl Shift A
Add New Item, with file as default
Ctrl Alt Down Arrow
Displays list of all open documents
Ctrl O
Open File Dialog
Monday, July 7, 2008
Visual Studio: Hot Keys: Refactoring
Note all of the Refactoring Hot Key Chords start with Ctrl R.
Ctrl + R E
Encapsulate a Field, creates a property from a field
Ctrl + R I
Extract an Interface, create a new interface from an existing class, interface or struct
Ctrl + R M
Extract Method, create method from code selection
Ctrl + R P
Promote to Parameter, promote a local variable to a parameter
Ctrl + R V
Remove Parameters
Ctrl + R R
Rename, allows renaming of identifier
Ctrl + R O
Change Order of Parameters
Ctrl + R E
Encapsulate a Field, creates a property from a field
Ctrl + R I
Extract an Interface, create a new interface from an existing class, interface or struct
Ctrl + R M
Extract Method, create method from code selection
Ctrl + R P
Promote to Parameter, promote a local variable to a parameter
Ctrl + R V
Remove Parameters
Ctrl + R R
Rename, allows renaming of identifier
Ctrl + R O
Change Order of Parameters
Sunday, July 6, 2008
C Sharp Interview Questions: Access Modifiers
Questions involving C# Access Modifier keywords.
1. Describe how the keyword "internal" affects access.
Answer: can only be accessed from the same assembly
2. Describe how the keyword "private" affects access.
Answer: can only be accessed from same class or structure
3. Describe how the keyword "protected" affects access.
Answer: can only be accessed from the class where it is declared or a derived class
4. Describe how the keyword "public" affects access.
Answer: No Restriction
5. Can multiple access modifiers be used on a member or type.
Answer: Only the combination "protected internal" is allowed
6. What is the default accessibility of an enum?
Answer: public
7. What is the default accessibility of an interface?
Answer: public
8. What is the default accessibility of a class ?
Answer: private
9. What is the default accessibility of an struct?
Answer: private
1. Describe how the keyword "internal" affects access.
Answer: can only be accessed from the same assembly
2. Describe how the keyword "private" affects access.
Answer: can only be accessed from same class or structure
3. Describe how the keyword "protected" affects access.
Answer: can only be accessed from the class where it is declared or a derived class
4. Describe how the keyword "public" affects access.
Answer: No Restriction
5. Can multiple access modifiers be used on a member or type.
Answer: Only the combination "protected internal" is allowed
6. What is the default accessibility of an enum?
Answer: public
7. What is the default accessibility of an interface?
Answer: public
8. What is the default accessibility of a class ?
Answer: private
9. What is the default accessibility of an struct?
Answer: private
Saturday, July 5, 2008
Index Of C# Interview Questions
Index Of C# Interview Questions
Actors
Agarwal Corollary
Agarwal's Law
AP Calculus
ASPNET account
backupfile
backupset
Bright Shiny Object
Bug Focus
Build
C#
Calculus
Code Pattern
Cognitive Load
Compact Net Framework
Coroutine
Daisy Chain Bug
Desktop Virtualization
DEV
Dot Net Framework
Dot Net Singularity
DotNet Singularity
Enterprise Agreement
enum
Even More Law
EventHandler
Exception
Exception Handling
Feature Focus
FileSystemWatcher
Firefox
Five Nines
Full Package Retail
Generator
GPS
helpctr.exe
hex literal
Hyper VTM
IEnumerable
IIS
Index
installer
INT
integer literal
Intellisense
Internet Explorer
Interviewing
Join
Linux
Micro Dot Net Framework
Microsoft Application Virtualization
Microsoft Team System
Microsoft Virtual PC
Mono
Moonlight
Moore's Law
msdb
msinfo.exe
msinfo.htm
MsTest
MultiBrain
MultiCore
multiplatform
MultiThread
Net Framework
NETWORK SERVICE
NUnit
Open Business
Open Value
Open Value Subscription
Parse
Permutation
Poisoned Candy
Prod
Production
QA
Refactor
Regex
Regression Bug
Requirements
Select License Agreement
Separation of Concerns
Serial Port
Server Virtualization
ServiceController
ServiceProcess
Silverlight
Snippets
Software Development
Software Development Practices
Source Control
Sprint
Sprint Aircard
SQL Server
Subroutine
System
System Info
System.Exception
Team Server
Team System Build
TfsBuild
Thread
ThreadStart
Three Nines
TryParse
UAT
uint
Unix
Use Case
User Acceptance Testing
VB.net
Version Control
Virtualization
Visual Studio
VJ#
Web Service
Win32
Win64
Windows Server
Windows Terminal Services
Windows XP
yield
Actors
Agarwal Corollary
Agarwal's Law
AP Calculus
ASPNET account
backupfile
backupset
Bright Shiny Object
Bug Focus
Build
C#
Calculus
Code Pattern
Cognitive Load
Compact Net Framework
Coroutine
Daisy Chain Bug
Desktop Virtualization
DEV
Dot Net Framework
Dot Net Singularity
DotNet Singularity
Enterprise Agreement
enum
Even More Law
EventHandler
Exception
Exception Handling
Feature Focus
FileSystemWatcher
Firefox
Five Nines
Full Package Retail
Generator
GPS
helpctr.exe
hex literal
Hyper VTM
IEnumerable
IIS
Index
installer
INT
integer literal
Intellisense
Internet Explorer
Interviewing
Join
Linux
Micro Dot Net Framework
Microsoft Application Virtualization
Microsoft Team System
Microsoft Virtual PC
Mono
Moonlight
Moore's Law
msdb
msinfo.exe
msinfo.htm
MsTest
MultiBrain
MultiCore
multiplatform
MultiThread
Net Framework
NETWORK SERVICE
NUnit
Open Business
Open Value
Open Value Subscription
Parse
Permutation
Poisoned Candy
Prod
Production
QA
Refactor
Regex
Regression Bug
Requirements
Select License Agreement
Separation of Concerns
Serial Port
Server Virtualization
ServiceController
ServiceProcess
Silverlight
Snippets
Software Development
Software Development Practices
Source Control
Sprint
Sprint Aircard
SQL Server
Subroutine
System
System Info
System.Exception
Team Server
Team System Build
TfsBuild
Thread
ThreadStart
Three Nines
TryParse
UAT
uint
Unix
Use Case
User Acceptance Testing
VB.net
Version Control
Virtualization
Visual Studio
VJ#
Web Service
Win32
Win64
Windows Server
Windows Terminal Services
Windows XP
yield
Friday, July 4, 2008
Visual Studio: Hot Keys: IntelliSense
IntelliSense Hot Keys
Ctrl + space or
Ctrl + K W
Complete word using the current selection in the list
Ctrl + J or
Ctrl + K L
Pull up the intellisense selection list
Ctrl + K I
Show the declaration of selected identifier in a Quick Info tool tip
Ctrl + Shift Space or
Ctrl + K P
Display for the specified method the name and parameters required
When Intellisense Selection List is displayed:
Ctrl causes the list to be rendered transparent
Ctrl + space or
Ctrl + K W
Complete word using the current selection in the list
Ctrl + J or
Ctrl + K L
Pull up the intellisense selection list
Ctrl + K I
Show the declaration of selected identifier in a Quick Info tool tip
Ctrl + Shift Space or
Ctrl + K P
Display for the specified method the name and parameters required
When Intellisense Selection List is displayed:
Ctrl causes the list to be rendered transparent
Thursday, July 3, 2008
Mono Dot Net Framework
Novell picked up leadership of the Mono project from Ximian. Since the common language runtime and dot net languages like C# have been submitted (and approved ) as ECMA standards, it should be possible to port the Dot Net Framework, Common Language Runtime and Dot Net languages to other platforms.
This is the goal of the Mono project. It currently can be run on Linux, some Unix, BSD, Mac OS X, Solaris and even Windows OSes. To do this the JIT (just in time compiler) needs to support many chipsets the x86, SPARC, S390, 64 bit x86 and others.
This is the goal of the Mono project. It currently can be run on Linux, some Unix, BSD, Mac OS X, Solaris and even Windows OSes. To do this the JIT (just in time compiler) needs to support many chipsets the x86, SPARC, S390, 64 bit x86 and others.
Wednesday, July 2, 2008
C Sharp Interview Question: Basic Part 1
Basic Questions.
1. Does C# support multiple inheritance?
No.
2. Can a class implement more than one interface?
Yes
3. Outline three exception handling code blocks"
try{} catch(){}
try{} finally {}
try{} catch() {} finally {}
4. When is the finally block executed?
When there is an error and a catch block is present the catch block executes first.
Following that the finally block is executed.
When there is no error, the finally block executed immediately after the last line in the flow of the try block.
5. What is the most common use of a finally block?
Release resources acquired or used in the try block.
6. Explain immutable in relation to C#.
All primitive types are immutable which means that after the type is constructed (allocated) it's value will not change. Statements that appear to change the value, actually cause the type to be constructed (reallocated) again.
7. For class named BaseClass and a class named DerivedClass, how would you declare DerivedClass to indicate that it directly inherits from base class?
class DerivedClass : BaseClass
8. What is the implicit parameter of set method of a property?
Value
9. What are three types of comments used in C#?
Single line comments '//'
Multiline comments that start with '/*' and ends with '*/'
XML comments '///'
1. Does C# support multiple inheritance?
No.
2. Can a class implement more than one interface?
Yes
3. Outline three exception handling code blocks"
try{} catch(){}
try{} finally {}
try{} catch() {} finally {}
4. When is the finally block executed?
When there is an error and a catch block is present the catch block executes first.
Following that the finally block is executed.
When there is no error, the finally block executed immediately after the last line in the flow of the try block.
5. What is the most common use of a finally block?
Release resources acquired or used in the try block.
6. Explain immutable in relation to C#.
All primitive types are immutable which means that after the type is constructed (allocated) it's value will not change. Statements that appear to change the value, actually cause the type to be constructed (reallocated) again.
7. For class named BaseClass and a class named DerivedClass, how would you declare DerivedClass to indicate that it directly inherits from base class?
class DerivedClass : BaseClass
8. What is the implicit parameter of set method of a property?
Value
9. What are three types of comments used in C#?
Single line comments '//'
Multiline comments that start with '/*' and ends with '*/'
XML comments '///'
Tuesday, July 1, 2008
Regular Expression Groups
Regular Expression Groups
===========
Sample Code
===========
string testIpString = "192.168.110.112";
string regularExpressionString = @"^(?<octet1>[01]?\d\d2[0-4]\d25[0-5])(\.)(?<octet2>[01]?\d\d2[0-4]\d25[0-5])(\.)(?<octet3>[01]?\d\d2[0-4]\d25[0-5])(\.)(?<octet4>[01]?\d\d2[0-4]\d25[0-5])$";
//Option 1//Match matches = Regex.Match(testIpString, regularExpressionString);
//Option 2//Match matches = Regex.Match(testIpString, regularExpressionString,RegexOptions.ExplicitCapture);
Console.WriteLine("Groups");
foreach (Group group in matches.Groups)
{
Console.WriteLine(group.ToString());
}
Console.WriteLine("Named Groups");
Console.WriteLine( matches.Groups["octet1"].ToString());
Console.WriteLine( matches.Groups["octet2"].ToString());
Console.WriteLine( matches.Groups["octet3"].ToString());
Console.WriteLine( matches.Groups["octet4"].ToString());
Console.ReadLine();
===============
Option 1 output
===============
Groups
192.168.110.112
.
.
.
192
168
110
112
Named Groups
192
168
110
112
===============
Option 2 output
===============
Groups
192.168.110.112
192
168
110
112
Named Groups
192
168
110
112
===============
Commentary
===============
Most of the power is in the regular expression:
@"^(?<octet1>[01]?\d\d2[0-4]\d25[0-5])(\.)(?<octet2>[01]?\d\d2[0-4]\d25[0-5])(\.)(?<octet3>[01]?\d\d2[0-4]\d25[0-5])(\.)(?<octet4>[01]?\d\d2[0-4]\d25[0-5])$";
===========
Sample Code
===========
string testIpString = "192.168.110.112";
string regularExpressionString = @"^(?<octet1>[01]?\d\d2[0-4]\d25[0-5])(\.)(?<octet2>[01]?\d\d2[0-4]\d25[0-5])(\.)(?<octet3>[01]?\d\d2[0-4]\d25[0-5])(\.)(?<octet4>[01]?\d\d2[0-4]\d25[0-5])$";
//Option 1//Match matches = Regex.Match(testIpString, regularExpressionString);
//Option 2//Match matches = Regex.Match(testIpString, regularExpressionString,RegexOptions.ExplicitCapture);
Console.WriteLine("Groups");
foreach (Group group in matches.Groups)
{
Console.WriteLine(group.ToString());
}
Console.WriteLine("Named Groups");
Console.WriteLine( matches.Groups["octet1"].ToString());
Console.WriteLine( matches.Groups["octet2"].ToString());
Console.WriteLine( matches.Groups["octet3"].ToString());
Console.WriteLine( matches.Groups["octet4"].ToString());
Console.ReadLine();
===============
Option 1 output
===============
Groups
192.168.110.112
.
.
.
192
168
110
112
Named Groups
192
168
110
112
===============
Option 2 output
===============
Groups
192.168.110.112
192
168
110
112
Named Groups
192
168
110
112
===============
Commentary
===============
Most of the power is in the regular expression:
@"^(?<octet1>[01]?\d\d2[0-4]\d25[0-5])(\.)(?<octet2>[01]?\d\d2[0-4]\d25[0-5])(\.)(?<octet3>[01]?\d\d2[0-4]\d25[0-5])(\.)(?<octet4>[01]?\d\d2[0-4]\d25[0-5])$";
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