This document introduces Behavior Driven Development (BDD) as a new development methodology. It discusses the benefits of BDD, including how requirements can be written in a simple format called Given-When-Then that is easy for both technical and non-technical people to understand. An example of writing a requirement for an email module in this format is given. BDD focuses more on specifying the behavior of a system rather than test cases. Tools like JBehave and SpecFlow can be used to implement BDD in Java and .NET projects.

1. A step towards next generation of development methodology??Say Hello to “Behavior Driven Development” “BEHAVIOR” sounds cool!I think I can add another “Buzz Word” in my resume!Mahmudul Haque Azad

2. A brief history (or story) of almost all developers

3. What is TDD and why it is needed??

4. But…I have been in development for years with lots of successful projects

5. Questions that raises in mindWHY the developers feel uncomfortable to write test code, even after completion of development? Is there any way to over come this?

6. Lets dig a practical example!TDD

7. What could be the possible test cases.This program should send email if To address is valid.This program should send email if CC address is valid even if To address is not valid This program should send email if BCC address is valid even if CC and To address is not valid. This program should send email even if the subject line is empty. This program should send email even if the body is empty.

8. And Then…

9. Lets find a cure!

10. What ifSpecification /RequirementBehavior of the ModuleHow it will behave in all possible situation?

11. At first! You must know how the medicine is going to work!Researchers have spent lots of time to figure out a possible format of “requirement specification” that is easy to understand to both technical and non technical person. Experts term this type of language as Ubiquitous Language or Domain Specific Language (DSL).

12. Lets learn some Buzz Word! Human Computer InteractionUbiquitious LanguageDomain Specific LanguageDDDDomain Driven Design

13. Why Buzz words in middle of such complex problem?

14. Good News!What ever your write follow Given-When-Then rule.

15. Can be written by any person regardless of technical background.

16. This plain English can be compliable!

17. Plain English to C#/Java/Python…I can be a language with a simple RULE but I have a name!

18. Here is the same requirement following this rule!Given that a web based email module has been developed And I am accessing it with proper authenticationWhen I shall write sender email address in To field Or write sender email address in CC filed by not keeping empty the To field Or write sender email address in BCC field by not keeping empty either To fieldAnd keeping the subject field non emptyAnd write something in body text area which excepts rich textAnd press or click send buttonThen my email will be sent And the event will be logged in log file.Isn't it easy to write and read and understand?

19. Isn't it covers and depicts all possible test cases?

20. Hey! Isn't it actually writing a documentation of email module to be developed?A new concept!Such type of requirement actually depicts how the module would behave once developed and developer can concentrate more on behavior rather than writing test cases. Such phenomenon are termed as Behavior Driven Development (BDD) and I am pretty sure you have understood the basic concept of BDD by now.Huh! I know BDD now and I can add it to my resume without hesitation!

21. Lets See BDD in Action!For Java: Use Jbehavehttp://jbehave.org/reference/stable/getting-started.htmlFor .Net use SpecFlow.