Category Archives: Week 3

Boundary Value and Equivalence Class Testing

This week in the Software Quality Assur&Test class we got the third assignment that was about Boundary Values and Equivalence Class Testing. We had worked during class time in different activities that covered this assignment so I would say I really enjoyed working in this assignment. We had to complete three parts each with a different level of difficulty. I learned to understand more of the way testing works and what exactly get tested.

What we covered in this homework:

Boundary testing is the process of testing between extreme ends or boundaries between partitions of the input values.

Robust Boundary Values. Introducing outside of boundary values.

Equivalence Class Testing, which is also known as Equivalence Class Partitioning (ECP) and Equivalence Partitioning, is an important software testing technique used by the team of testers for grouping and partitioning of the test input data, which is then used for the purpose of testing the software product into a number of different classes.

Weak Normal Equivalence Class Testing: In this first type of equivalence class testing, one variable from each equivalence class is tested by the team. Moreover, the values are identified in a systematic manner. Weak normal equivalence class testing is also known as single fault assumption.

Strong Normal Equivalence Class Testing: Termed as multiple fault assumption, in strong normal equivalence class testing the team selects test cases from each element of the Cartesian product of the equivalence. This ensures the notion of completeness in testing, as it covers all equivalence classes and offers the team one of each possible combinations of inputs.

Worst-Case boundary value analysis is a Black Box software testing technique.

In Worst case boundary value testing, we make all combinations of each value of one variable with each value of another variable.

Edge Testing is a combination of Boundary Value Analysis and Equivalence Class Testing.

Weak Robust Equivalence Class Testing: Like weak normal equivalence, weak robust testing too tests one variable from each equivalence class. However, unlike the former method, it is also focused on testing test cases for invalid values.

Strong Robust Equivalence Class Testing: Another type of equivalence class testing, strong robust testing produces test cases for all valid and invalid elements of the product of the equivalence class. However, it is incapable of reducing the redundancy in testing.

From the blog CS@Worcester – Tech, Guaranteed by mshkurti and used with permission of the author. All other rights reserved by the author.

Be The Worst

This time the pattern that I would like to write about is Be the Worst. I always thought about which is better, to be the worst on the best team or the best on the worst team? This pattern explains that is better to find a stronger team where you are the weakest member and have room to grow. When you are in a strongest team you learn from them and makes you feel perform better. The other members of that team will often prevent you from making mistakes, and help you recover from mistakes so smoothly that you won’t realize that you may not be learning as much as you think. 

I have been part of both cases. I have practice being the best in a group and vice versa and I would choose to be the worst any day. Personally, I’d rather be the weakest player in a strong team. That makes me look like a better player, and it helps me develop the skills to become a better player. When I worked in a project with some of my teammates that had more knowledge and experience than me, I was able to improve myself and learn some tips than books or videos would show me or learn you.

When you are in a group like this it is easy to forget, and you start compare yourself with the best and sometimes you feel stupid or not doing enough. I felt that in more than one occasion, but this pattern has reminded me another thing that I have forgotten. Your goal is to measure your abilities and find ways to be better than you were yesterday. We’re all on the same journey and comparing ourselves to others is useful only when it allows us to find ways to help each other improve.

I believe every pattern has its own good and bad sides. You can’t stay for a long time being the worst in a team because the phase where you learn ends and team moves on and so do you.  Being the worst on a team of outstanding developers can’t be compensated for with environment, equipment, or money. You can’t compensate for learning next to people who have already traveled the path and know how to avoid the holes on the road ahead. Pairing with great software developers is invaluable.

Source:
Apprenticeship Patterns by Adewale Oshineye; Dave Hoover, Be the Worst

From the blog CS@Worcester – Tech, Guaranteed by mshkurti and used with permission of the author. All other rights reserved by the author.

Apprenticeship Patterns

The book Apprenticeship Patterns: Guidance for the Aspiring Software Craftsman by Dave Hoover and Adewale Oshineye gives great solutions/patterns for problems often faced by software developers, mainly apprentices or beginners of the craft. I have enjoyed reading up to where I have gotten so far (Chapter 1 plus 2-6 introductions) and it has taught as well as clarified many ideas and methods. One thing I have never thought of is how your first language will affect how you will think and learn other languages in the future. While this may be the case, the more diverse knowledge you have, the more you will improve upon this fact. For example (given by the book), people who are more comfortable with object-oriented languages should explore functional languages. This will broaden your understanding and problem solving. Another pattern I found interesting was the Be The Worst pattern. This discusses your environment and its relation to your growth. Being on a team where you are the best or most skilled does not give you much room or motivation to improve as you will not be learning from your peers. It suggests keeping yourself in an environment/team where you are the least skilled. This forces you to catch up to your teammates so that you don’t hold them back as well as forces the habits, ideas, and information of your higher skilled teammates upon you. A few patterns that addressed things I already “knew” but clarified the process at which I should take are Expand Your Bandwidth and Reading List. If you want to be a software developer then you should already know that you will be constantly learning. Expand Your Bandwidth gives solutions on how to learn more than what your job teaches you. It gives examples such as joining online academic courses, following influential developers on social media, contacting authors and more. This gives you a starting point from which you can come up with your own ways of learning or just to boost you in the right direction. The other pattern, Reading List, gives great methods on organizing your book backlog. The first suggestion is to not only keep a list of books you wish to read but the ones that you have read as well. This allows you to keep track of the books you’ve read from which you can review and find gaps or trends in your learning. This can direct you/help decide what you should read next. The pattern also suggests that you keep your book list as a priority queue. If you find a book on a topic that would be more useful or has a higher urgency then put it at the top of the list. If the bottom of the list gets to the point where you will probably never read the books in those spots then thats okay because it clearly is not a priority. I like the way this book structures these patterns too. The authors organize these patterns into Context, Problem, Solution and Action. This makes it easier to understand rather than if they were just put into normal paragraphs.

From the blog CS@Worcester – Austins CS Site by Austin Engel and used with permission of the author. All other rights reserved by the author.

Apprenticeship Patterns Chapter 1 and Chapter 2-6 Introductions

Software Craftsmanship raises some of the thorniest and most sensitive questions about software development and comes to the controversial conclusion of finding answers in a system that has thrived for hundreds of years: technology. Software Technology is a systematic expression of the author’s ideas and attempts to answer the difficult questions that have been plaguing the software industry. How should we restructure the process of building software, such as we want it to be effective?

 

The author of Software Craftsmanship has been emphasizing the role of the craftsman in the project. Craftsmen sounds is a very old word, the craftsman in other industries is a what kind of person I want to say, must be done in the field of a good man, I explain the below mentioned software process artisans do what kind of person, craftsman is mentioned there is a very rich in the process of software development experience, after years of development, products are well received by customers, has a certain reputation, they can submit a robust, high quality of the user application. A good craftsman can make or break a project. This shows that the human factor plays a very important role in the development of the project. Someone I have been thinking without learning software engineering in software development has a very important role in understanding of software engineering make me realize software can also like assembly line engineering, development mode, people do not development process, mainly the development process of software engineering control, a relatively fixed process, as long as people do some mechanical work can complete this project. In the current environment, software engineering ideas are still dominant, but software technology ideas also have their base of support, such as workers in the open-source community.

 

Software technology of the main pressure is a very important role in the whole project, software process is very strict requirements of the team, the team first small number, no more than 15 people, the general team is three people, but for the team of personal ability request, the other teams also are in high demand of health, a more stable team, team members can develop the tacit understanding.

 

The book Software Craftsmanship gives us a good development model, but many projects in the current environment are developed using software engineering ideas. Why is this? In my analysis, the main reason is that software technology requires too much of the team, and there are too few excellent craftsmen, so it is difficult for many companies to organize such an efficient team. Right now, the idea of software craftsmanship can only be seen in the open-source community, where many of the true craftsmen are gathered.

From the blog haorusong by and used with permission of the author. All other rights reserved by the author.

Apprenticeship Patterns

We are at the point of life that in a few years we all be fully working adults. It is crazy to think that 4 years of college just flew by so fast. This semester the software capstone class will be the most interesting and challenging I believe. When it comes to reading a book, I have no patience at all, but after reading the introduction, something about this book: Apprenticeship Patterns: Guidance for the Aspiring Software Craftsman is making me want to read it appropriately. It is possible to be that I can relate to this book on so many levels and it is relevant to me. After just reading the introduction I feel like it changed the way I think and view my profession.

All the patterns in the book are interesting and powerful in a way that we can adapt and combine these patterns in many ways and situations. One of the patterns that stood out to me the most was “Be the worst” from chapter four. The author has explained the concept very well in which it states that “Surround yourself with developers who are better than you. Find a stronger team where you are the weakest member and have room to grow” This statement Is very interesting and when I think deep into it, I believe that being worst in a team at least for me is a motivation to work hard and grow to improve. The goal is not to stay the weakest but instead work my way from the bottom to the top.

The author also talked about the risk factor that associates with being worst in the team including dragging the team down, good teams do not tolerate you, and the risk of being fired. Although I do agree that in situations all these scenarios could be possible but on the positive side this can motivate a person to improve and build a mindset that helps the individual. I do not think I disagree with any aspects of the pattern but, these patterns and the whole book have certainly changed the way I think about a certain aspect of software development. I realized that I need to work even harder and push myself to the limits for me to get where I want in life.

 

 

 

From the blog Derin's CS Journey by and used with permission of the author. All other rights reserved by the author.

Apprenticeship Patterns Blog Post #1

Throughout this semester, I will be reviewing several different apprenticeship patterns from the first six chapters of our in class textbook. For my very first post, I decided to review the first pattern covered which was “Your First Language.” For many of my friends and classmates (including myself), Java was the first language learned. When we are first starting out learning programming, the book tells us that it is incredibly valuable to master our first language or two rather than try to learn a bunch of different languages at once. I am a firm believer in this notion as well simply because, with my knowledge in Java, I am able to translate to other languages fairly easily. The book explains that trying to learn all the languages instead of one for when a programmer is just starting out is not ideal mainly because it will end up causing more confusion than learning. If I am great at my first language, it is generally not too difficult to solve a problem in that language and then translate it to a new language after the fact. A great quote the book uses to describe this is by Alfred North Whitehead, and it reads, “by relieving the brain of all unnecessary work, a good notation sets it free to concentrate on more advanced problems, and in effect increases the mental power of the race.” It definitely is a bit concerning to me when I see job applications stating I need to know certain languages or programs that use specific languages, but my original background in Java has proven to be extremely helpful in learning how to use those other languages. All the work I put into learning Java has helped me with my understanding of all languages, and for the most part, I just end up needing to teach myself the slight syntax differences between them all. This portion of the textbook spoke to me strongly because I have often thought about what would have happened if I had learned a different language for my first language. I see now that it most likely would not have changed anything, and that makes me happy!

From the blog CS@Worcester – Tim Drevitch CS Blog by timdrevitch and used with permission of the author. All other rights reserved by the author.

CSS Grid: A Better Layout System

Whenever I find myself working on a website, one of the more time-consuming aspects of development is often the CSS (cascading style sheet) code which controls the layout of the site. While CSS properties often have names which are self-explanatory the various formatting tools in CSS can oftentimes be confusing to me.

In the past, using the float property and various div classes to control different sections of the website was my go-to when building webpages for practice. This has since been proceeded by a number of new layout systems now baked into CSS functionalities as more recent versions of CSS have worked to better support modern web-development concepts. As I am looking to improve and modernize my web-development skills to prepare for contract work in the future, it was important that I start looking into the newer layout systems provided by CSS.

The newest layout system introduced by CSS, CSS Grid, is a fairly recent invention. I was looking for a good reference to introduce me to the idea, and I found a great resource on the website css-tricks.com (https://css-tricks.com/snippets/css/complete-guide-grid/), which focuses on providing relevant information regarding various CSS standards and techniques. The article provides a complete introduction to the idea of Grid, starting with it’s various properties (display: grid to begin using the layout, various grid-template properties and grid-column/grid-row to control the particular layout of content) and moving further to discuss more specific techniques associated with Grid. I felt that the information about defining gutters (spaces between grid items) was extremely helpful, as gutters vs. borders in web design has been a hard topic for me to wrap my head around for a while, and this page put it into a really easily-understandable format in my opinion.

CSS grid is absolutely what I would use for a modern website design if I were making a site for someone in 2020. Although there exist frameworks such as Bootstrap and Skeleton, a lot of the inner-workings of the page and its layout can be obstructed in a way, and I feel like Grid makes it easy enough to make a great layout without relying on an external framework. Keeping things simple in web-design has always made for a more manageable website in my experience. I would certainly recommend this article to anyone looking to explore CSS Grid as a layout option for a website, the plentiful examples and images make concepts easy to visualize, and the explanations provide a good level of information without seeming overwhelming to someone unfamiliar with the topic.

With CSS grid, I think web-development (in terms of front-end) has become much more accessible, and building a functional and aesthetically pleasing website has become far easier than in the past when reliance on outdated layout formats made things a lot more difficult.

Site Referenced: CSS-Tricks.com

Great resource for learning more about CSS grid!

From the blog CS@Worcester – CodeRoad by toomeymatt1515 and used with permission of the author. All other rights reserved by the author.

S.O.L.I.D Principles

 This week on my CS Journey, I want to talk about the SOLID design principles. I am sure that you have heard the term many times, however, let us look at the principles in detail. The reason I picked this topic is as a Computer science major student we write many programs and having a strong principle will enable us to write effective object-oriented code. 

To start of SOLID is an acronym where each letter represents a software design principle. 

S – for Single Responsibility Principle

O – for Open/Closed Principle

L – for Liskov Substitution Principle

I – for Interface Segregation Principle

D – for Dependency Inversion Principle

 

Each principle overlaps here and there. The Single Responsibility Principle states that in a well-designed application, each class should have only one single responsibility. essentially meaning a class should only have one job. I think this is a very good concept to use because when you are working with complex programs and the class has more than one responsibility it will become a nightmare. The open-closed principle states that classes should be open for extension but closed for modification. For example, I learned that if you want to add a new feature to your program you should do it by extending it rather than modifying it which minimizes the risk of failures. Next, the Liskov Substitution Principle which explains that an object of a superclass can be replaced with objects of its subclasses without causing problems to the application. This means that a child class should never change the characteristics of its parent class.

 

The  Interface Segregation Principle is the fourth SOLID design principle that states no clients should not be forced to depend on methods they don’t use.  In other words, interfaces shouldn’t include too many functionalities since the interfaces are difficult to maintain and change over time, so it is best to avoid. Lastly, the Dependency Inversion Principle states that the High-level modules or classes should not depend on low-level modules/classes and both should depend upon abstractions because a change in one class can break another class which is very risky.

 

Overall, the blog I read talked about each principle in detail using various examples such as UML diagrams, Java programs, and other diagrams that helped me to understand each concept. I learned a lot from the blog, and I think that these concepts are all key to writing a good solid code. In the future, I will be using the principles to write effective object-oriented code. 

 

 

Here is the blog I Used:

https://raygun.com/blog/solid-design-principles/

From the blog Derin's CS Journey by and used with permission of the author. All other rights reserved by the author.

Design Patterns

This week I would like to talk about the design patterns. I would like to give a little intro to design pattern. As you have probably experienced by now, writing correct computer programs can sometimes be quite a challenge. Design patterns are not language specific either. Good design patterns are implementable in most programming languages, depending on the capabilities of the language of course. They also speed up the development process by providing tested and proven development paradigms.

Effective software design requires considering issues that may not become visible until later in the implementation process. Reusing design patterns helps to prevent subtle issues that can cause major problems later. It also improves code readability for programmers and architects familiar with the patterns. In addition, patterns allow developers to communicate using well-known, well understood names for software interactions.

Correctly using a design pattern is very important. Implement it in the wrong way and it can create more problems than it solves.

In my CS-343 class we worked a little with design patterns and how they work. It is uncommon to introduce design patterns and not explain who the Gang of Four are. The Gang of Four are the authors of the book, “Design Patterns: Elements of Reusable Object-Oriented Software”: Erich Gamma, Richard Helm, Ralph Johnson, and John Vlissides. The Gang of four design patterns are divided into 3 fundamental groups:

Creational Patterns provide ways to instantiate single objects or groups of related objects.

Structural Patterns provide a manner to define relationships between classes or objects.

Behavioral Patterns define manners of communication between classes and objects.

My favorite book about design principles is “Head First Design Patterns” by Kathy Sierra; Elisabeth Robson; Bert Bates; Eric Freeman. It is one the best for the introduction to this topic. I suggest the first chapter which gives you an understanding of the design patterns. In this chapter, you will learn why (and how) you can exploit the wisdom and lessons learned by other developers who have been down the same design problem road and survived the trip. Before we are done, we will look at the use and benefits of design patterns, look at some key OO design principles, and walk through an example of how one pattern works. The best way to use patterns is to load your brain with them and then recognize places in your designs and existing applications where you can apply them. Instead of code reuse, with patterns you get experience reuse.

From the blog CS@Worcester – Tech, Guaranteed by mshkurti and used with permission of the author. All other rights reserved by the author.

SOLID Design Principles

Hello everyone and welcome back.

 This week I will be exploring three of the five design principles of OOP; Single Responsibility Principle (SRP), Open-Closed Principle (OCP), Liskov’ Substituion Principle (LSP), Interface Segregation Principle (ISP), and Dependency Inversion Principle (DIP).

My first introduction to these principles was in reading “Clean Code: A Handbook of Agile Software Craftsmanship” by Robert C. Martin. Prior to learning these concepts, my code was messy and not easily modified. I used to put way too many methods in classes, and my child classes were not fully compatible with the parent classes. I chose this topic because we all benefit when our code is adaptable, clear-cut and easy to maintain. I chose this blog because the author presents the information in a very direct format with great examples.

The purpose of these design principles is to make our code easier to maintain, change and understand. As software engineers, a lot of the code most of us will be working on will be code that others have written. There will be others who will be maintaining our code when we are no longer working on it. When we follow these design principles, not only do we improve our coding skills, but we help those who maintain the code we have written.

Single Responsibility Principle (SRP) means that a class should have only one purpose/task that it is responsible for. This makes code more maintainable by making software more comprehensible for future changes to be made. If a single class has multiple responsibilities, editing in the future will be more complicated because we will have to make additional changes to the classes that are dependent on it. You will have to update and recompile dependent classes that are not directly related to the change you needed to make.

Open-Closed Principle (OCP) means functions, classes and modules should be written such that others can add to them but not change the core elements. When we use this principle our code, our software will give less errors when requirements change. This makes our code more robust and reusable.

Liskov’s Substitution Principle states that every dependent class should be substitutable for their parent class without breaking functionality. Our validation rules on input parameters in subclasses should not be stricter than the input parameters on the parent. Using this principle increases maintainability of our software by making our class hierarchies easier to understand.

Through utilizing these design principles, I will be a better software engineer. I am more aware of ways to improve the legibility, and modifiability of my code. These design principles will help me stay away from poor coding practice.

Blog of Inspiration:

https://android.jlelse.eu/solid-principles-the-definitive-guide-75e30a284dea#.xq7a6fvtk

From the blog cs@worcester – Coding_Kitchen by jsimolaris and used with permission of the author. All other rights reserved by the author.