Skip to main content

How did I start practising BDD?


In the beginning days, I have practiced TDD (Test Driven Development) using JUnit, I approached that I should test methods belong to a class. For example:

I have a class with some methods:

public class A{
 public void method1(){

 }

 public void method2(){

 }
}

And then, I wrote some test methods to check the corresponding ones, for example:

public class ATest{
 @Test
 public void testMethod1(){
  ....
  assertTrue(...);
  .....
  assertEquals(...);
 }

 @Test
 public void testMethod2(){
 }
}

After that, I know that a test method (ex: testMethod1) should just only test one thing, so I decided to write more methods for each case. It looks like the following:

@Test
public void testMethod1_When_Case1(){
 ....
 assertTrue(...);
}

@Test
public void testMethod1_When_Case2(){
 ....
 assertEquals(...);
}

However, it was not a really good approach because it seems that I just focused on test the functionality of the method of the class. With the TDD approach, I knew that I should test the behaviors of a class, not the methods that belong to this class. Because we all know the class's behaviors have represented the behaviors of our system.

Therefore, I would like to turn to a behavior testing approach; and BDD (behavior-driven development) is my response. Here is it:

- From the requirements, I call them are user stories in Agile. Something likes:
As a [Role]
I want [Feature]
So that I receive [Value]
I define some acceptance tests in order to know what exactly their values are. These acceptance tests have represented the behaviors of my system. Somethings likes:
Given [Context]
When [Event Occurs]
Then  [Outcome]
- From the acceptance tests, I started to build a class that implements the behaviors. With TDD and BDD  approach together, I start writing test code first. For example:

@Test
public void shouldReceiveOrDoSomethingWhenEvent1Occurs(){
}

@Test
public void shouldReceiveOrDoSomethingWhenEvent2Occurs(){
}

Yeah, that was all. Now, I follow this approach and I have a test case that represented the behavior of a class, not only the test for a method as previously.

References:
[1]. http://dannorth.net/introducing-bdd/
[2]. http://www.ryangreenhall.com/articles/bdd-by-example.html

Comments

Popular posts from this blog

[Snippet] CSS - Child element overlap parent

I searched from somewhere and found that a lot of people says a basic concept for implementing this feature looks like below: HTML code: <div id="parent">  <div id="child">  </div> </div> And, CSS: #parent{   position: relative;   overflow:hidden; } #child{   position: absolute;   top: -1;   right: -1px; } However, I had a lot of grand-parents in my case and the above code didn't work. Therefore, I needed an alternative. I presumed that my app uses Boostrap and AngularJs, maybe some CSS from them affects mine. I didn't know exactly the problem, but I believed when all CSS is loaded into my browser, I could completely handle it. www.tom-collinson.com I tried to create an example to investigated this problem by Fiddle . Accidentally, I just changed: position: parent; to position: static; for one of parents -> the problem is solved. Look at my code: <div class="modal-body dn-placeholder-parent-position&quo

The HelloWorld example of JSF 2.2 with Myfaces

I just did by myself create a very simple app "HelloWorld" of JSF 2.2 with a concrete implementation Myfaces that we can use it later on for our further JSF trying out. I attached the source code link at the end part. Just follow these steps below: 1. Create a Maven project in Eclipse (Kepler) with a simple Java web application archetype "maven-archetype-webapp". Maven should be the best choice for managing the dependencies , so far. JSF is a web framework that is the reason why I chose the mentioned archetype for my example. 2. Import dependencies for JSF implementation - Myfaces (v2.2.10) into file pom.xml . The following code that is easy to find from  http://mvnrepository.com/  with key words "myfaces". <dependency> <groupId>org.apache.myfaces.core</groupId> <artifactId>myfaces-api</artifactId> <version>2.2.10</version> </dependency> <dependency> <groupId>org.apache.myfaces.core<

Attribute 'for' of label component with id xxxx is not defined

I got the warning in the log file when I have used the tag <h:outputLabel> without attribute " for " in xhtml file. It was really polluting my server log files. The logged information actually makes sense anyway! We could find an answer as the following: "Having h:outputLabel without a "for" attribute is meaningless. If you are not attaching the label, you should be using h:outputText instead of h:outputLabel." However, these solutions are not possible just for my situation. Instead of using h:outputText for only displaying text, my team has used h:outputLabel too many places. We were nearly in our release time (next day) so it is quite risky and takes much efforts if we try to correct it. Because the style (with CSS) is already done with h:ouputLabel . The alternative by adding attribute " for " the existing h:outputLabel is not reasonable either. I really need to find another solution. Fortunately, I came across a way if I cha

How to apply Lean - Kanban for your business

This is the topic of Scrum Breakfast meetup this time, speaker: Ms. Phuong Bui - Technical Project Manager of YOOSE Pte. Ltd. http://www.meetup.com/Scrum-Breakfast-Vietnam-Agile-and-Scrum-Meetup/events/230313727/ Lean comes from Lean manufacturing is a method that focuses on elimination of wastes. In other words, this is a set of principles for archiving the quality, speed and customer alignment. The first time I knew about the term "Lean" is  from the book Software Craftsmanship . Sandro recommends if we want to transform our pet projects into a real business, we should get familiar with Lean Startup concepts. In this talk, Ms. Phuong pointed out some major wastes includes information (ex: unclear requirements), processes (ex: waiting), physical environment and people. Knowing what the problems should be the best way to eliminate them. The difference between  Single item flow and Batch processing is the second main point; and it is the Lean's idea. Batch pr

Math fundamentals and Katex

It was really tough for me to understand many articles about data science due to the requirements of understanding mathematics (especially linear algebra). I’ve started to gain some basic knowledges about Math by reading a book first. The great tool Typora and stackedit with supporting Katex syntax simply helps me to display Math-related symbols. Let’s start! The fundamental ideas of mathematics: “doing math” with numbers and functions. Linear algebra: “doing math” with vectors and linear transformations. 1. Solving equations Solving equations means finding the value of the unknown in the equation. To find the solution, we must break the problem down into simpler steps. E.g: x 2 − 4 = 4 5 x 2 − 4 + 4 = 4 5 + 4 x 2 = 4 9 x = 4 9 ∣ x ∣ = 7 x = 7  or  x = − 7 \begin{aligned} x^2 - 4 &= 45\\ x^2 - 4 + 4 &= 45 + 4\\ x^2 &= 49\\ \sqrt{x}&=\sqrt{49}\\ |x| &= 7\\ x=7 &\text{ or } x=-7 \end{aligned} x 2 − 4 x 2 − 4 + 4 x 2 x ​ ∣ x ∣ x = 7 ​ = 4 5 = 4 5 + 4 = 4