Service Encapsulation is often used to hide the internal representation, or state, of an object from the outside. In this way, we can present to the outside world a cleaner, simpler, and more coherent view of the internal systems. Many services which were not initially planned for a Service Oriented Architecture (SOA) may get encapsulated or become a part of a SOA in this way.

In the example of ACME Social and University of Nowhere, both the parties agreed on exchanging information in order to improve the existing geolocation service of ACME Social. In particular, ACME Social would like to receive the following information from the University of Nowhere:

• Retrieve a list of unique IDs of the students
• Retrieve the email addresse(s) of each student
• Get the class that the student is supposed to follow
• Retrieving the exact coordinates of the location of a given student according to the University of Nowhere.

Service Encapsulation: Can we design it as a stateless service?

Probably yes, even though students and their respective locations will change. From the point of view of the methods, we can expect that their behavior will not change over time. A possible UML diagram that describes the interface of the service could be as follows:

The class represents all the functionalities requested by ACME Social in 4 methods. It does not have attributes and this approach will keep the design simple. IDs, emails, as well as geocoordinates will be shared as Strings in order to use one of the basic types of a service.

In the case we will decide to implement a WS-I compliant service, we can assume that the calls of the methods can fail and may trigger exceptions on the service consumer’s side.

What about the concerns of ACME Social and the documentation of the service?

As the service represents the entry point of the systems of the university of Nowhere, we need to carefully balance the complexity of the interface that we need to design. On the one hand, it must be able to mask all the idiosyncrasies of the IT of the university in order to facilitate its consumption by ACME Social. On the other hand it must be able to deliver everything that is needed and agreed. The figure below shows how this interface sits at the intersection points of two different worlds with different needs and goals:

ACME Social, i.e. the client of the service needs a clear answer to the following questions:

• What does the service do? Answering to this question will require a proper documentation of the methods. The name may be intuitive, but some of its behavior may not. Therefore, it needs to be carefully documented.
• How can we use the service? The best way to answer this question is with an example of use. ACME social may use different languages so the example(s) need to be written in Java and Python (for example) and the code must be well documented (see these best practices).
• Where can we locate the service? The URL of the service, together with the way to get the authorization of use, should be part of the documentation. In addition, the service should be part of an UDDI registry as well.

ACME Social is not at all interested in:

• How to represent internally the request received from ACME social
• How to implement the service
• Where to host the server needed for running the service
• How to publish the service in the Internet
• How to keep it running

These aspects are of fundamental importance for the University of Nowhere. However, these concerns should not be shared with the consumers of the service.

A #service Encapsulation example using a location service. #servicedesign #programming
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Let’s start from the beginning. Do you know what is the most popular social network? This video will give you the answer:

You may have guessed right. However, based on this video that you just saw, are you able to say something about how and why people connect, what are the implications of their connections, and how they communicate?What do they exchange in their communications? Let me introduce you to Graph theory.

A graph in this context is made up of vertices (also called nodes or points) which are connected by edges (also called links or lines).

This is a relatively unexplored branch of mathematics, and this video provides you with a more formal definition. Warning, it contains a fair bit of mathematics:

There are several applied usages of this theory that cover many aspects of our life. The discipline is known as social network analysis and it is the application of graph theory to the modelling and analysis of social systems such as

• Internet hyperlinks connections
• distribution of obesity among population
• spreading of a disease
• power strictures in an organization
• and many more

This video introduces the concept:

To give you a better idea of what we are talking about, if you are a Twitter user, you can see an example of a practical usage at this link:

• https://analytics.mentionmapp.com/

If you are familiar with Python and you are searching some libraries, in the video below you can find an example of how to conduct a simple analysis. The author also made the code available in GitHub.

If you intend to take a more bird eye view and bring a business aspect into the equation, the Business Networks approach also follows Graph theory. Macro behavior and characteristics can be derived from a similar analysis. Some best practices will be introduced in Business Process Integration.

This is a small introduction of Social Networks and Social Network Analysis. However, it represents just the tip of the iceberg. In case the topic triggers your curiosity and you would like to know more, I summarized a collection of (scientific) resources in the following scientific paper: A Survey of Social Software Engineering.

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Value Chain

A value chain is a combination of the systems a company or organization uses to make money. In other words, a value chain is made up of all the various subsystems that are used to create products or services. This includes the company’s processes from start to finish.

Michael Porter developed a strategic management tool for analyzing a company’s value chain. In his book “Competitive Advantage” (published 1985), Porter laid out his method of analyzing value chains. He sought to define a company’s competitive advantage noting that it stems from the company’s processes, such as marketing and supporting activities.

All five primary activities are essential in adding value and creating a competitive advantage. They are:

• Inbound logistics: arranging the inbound movement of materials, parts, and/or finished inventory from suppliers to manufacturing or warehouses, assembly plants, and retail stores
• Operations: managing the process that converts inputs (raw materials, labor, and energy) into outputs (goods and/or services).
• Outbound logistics: the process related to the storage and movement of the final product and the related information flows from the end of the production line to the end user.
• Marketing and sales: selling processes and products for creating, communicating, delivering, and exchanging offerings that have value for customers, clients, partners, and/or society at large.
• Service: all the activities required to keep the product working effectively for the buyer after it is sold and delivered.

Companies can harness a competitive advantage at any one of the five activities in the value chain. For example, by creating outbound logistics that are highly efficient or by reducing a company’s shipping costs, they can either realize more profits or pass the savings to the consumer in the form of lowered prices.

The use of support activities helps make primary activities more effective. Increasing any of the four support activities helps at least one primary activity to work more efficiently.

• Infrastructure: consists of activities such as accounting, legal, finance, control, public relations, quality assurance, and general (strategic) management.
• Technological development: pertains to the equipment, hardware, software, procedures, and technical knowledge brought to bear in how the company transforms inputs into outputs.
• Human resources management: consists of all activities involved in recruiting, hiring, training, developing, compensating, and (if necessary) dismissing or laying off personnel.
• Procurement: the acquisition of goods, services, or works from an outside external source. In this field, the company also makes decisions concerning purchases.

The video below introduces the value chain and discuss the benefits of this model as well as its limitations:

System Dynamics

System dynamics is a methodology and a mathematical modeling technique to frame, understand, and discuss complex issues and problems. Originally developed in the 1950’s to help corporate managers improve their understanding of industrial processes, System Dynamics is currently being used throughout the public and private sector for policy analysis and design.

System dynamics tries to understand the nonlinear behavior of complex systems over time using the following key concepts:

• Stock: an accumulation of people or things in a specific location or with a specific condition in a system. An element of a system that accumulates or drains over time. Stocks are the memory of a system and are only affected by flows.
• Flow: the movement of people or things between stocks within a system boundary or across the model boundary and thereby into or out of the system (through sinks and sources); changes in stocks over time. Flows represent activity, in contrast to stocks that represent the state of the system.
• Feedback: when the effect of a causal impact comes back to influence the original cause of that effect. A feedback loop is an alternating sequence of variables and causal links that creates a closed ring of causal influences.
• Table function: a numeric table version of a graphical function.
• Time delay: a delay in the flow of conserved material or people.

The video below provides an introduction to the concept:

The lecture below gives a set of examples as well as familiarizes you with the concept of System Dynamics:

I hope that these videos will serve as an introduction for understanding the dynamics that drive a company.

The post On Understanding the Dynamics that Drive a Company: Value Chain and System Dynamics appeared first on Francesco Lelli.

In order to set up the mood for this exercise I recommend you to watch the following video:

The rest of this article share with you the current situation of your mission (should you chose to accept it) and is structured as follows: First (section 1), the background is introduced. Then, the case study (Section 2) is briefly described and the interview that you had with various stakeholders (section 2.1 and 2.2) are articulated. Finally (Section 3) presents the details of your tasks.

1 – What happen before: the background story

The University of Nowhere made an agreement with a popular web based social network[1], named ACME Social, in order to share its information about its students and its lecturers.

The business agreement is on the line of what follows: “we will provide you the information that you require and, if one of your customers, would like to use these information you will pay us 10% of your sale”.

The legal department of the University of Nowhere validated this agreement. They decided to amend the subscription of each students with offering the possibility to opt out for preserving their privacy. However, if the student do that he/she will not be able to subscribe to the exams (i.e. he will never graduate!).

Student associations have been consulted and they do not see any difference from how this information are currently handled by popular eCommerce websites[2]. Consequently, they decide to support this initiative. Possible reasons for giving their support includes: (i) a potential (but not certain) reduction in the tuition costs of all the students and (ii) a share of the 1% (this is certain) of the revenue that the University of Nowhere will make. It will be transferred to the bank accounts of the associations that will support the initiative (and only to them).

Now that the various business agreements are in place, the rector magnificus has decided to investigate on the real possibility to implement what has been promised to ACME Social (really!?!? Not before!?!?). In his infinite wisdom, he decided to appoint you as his adviser and he is expecting concrete and actionable insights in order to move forward this initiative.

2 – BPI: The Case Study

You did not waste your time and you immediately started working on it. After all this is real life, not just an example of Business Process Integration. You see this as a fantastic opportunity for advancing your studies in the right way. Clearly a lot of professors of the Department of Impossible Computing are looking at what you are doing and, if successful, you will probably have the luxury of choosing your mentor for the master thesis freely. In addition, he/she will help you in securing a state of the art internship that will boost your future career.

You identified the IT department and ACME Social as your core stakeholders. After all, the various divisions of the university agreed to support this initiative and they all use the IT department for storing their information. Therefore, in principle, the IT is the gatekeeper of all the information of the University of Nowhere.

You did a few meetings with:

• ACME Social: in order to understand what kind of information they want and how and when they would like these data. In other words what kind of format they would like to process and how they envision the transferring of /accessing to these data.
• The IT department: in order to understand what information are available and what systems are involved.

The following subsections describe the outcome of these meetings.

2.1 Minute of the Meeting with ACME Social

ACME Social would like to enrich its data with a precise location of the students. After all, the university is a “very compact environment” where different students coexists. They initially thought about using GPS coordinates from the mobile phones of the students. Unfortunately, the precision, in particular if inside a building, is not accurate enough. Consequently, they would like to combine the GPS information with additional information. In particular they would like to leverage the fact that students follow classes. By combining them they would be able to achieve a more precise geo-location insight the campus.

Some of the functionalities that they would like to implement are:

• Retrieve a list of unique ID of the students
• Retrieve the email(s) of each student
• Get the class that the student is supposed to follow
• Retrieving the exact coordinates of the location of a given student according to the University of Nowhere.

Note that in a real case the information that ACME Social would like to acquire will be much more. However, for the purpose of this exercise we will limit to these four.

2.2 Minute of the Meeting with the IT Department

You had a very, very, very long discussion with the IT department and you analyzed 15-een possible systems that may provide the information that you are seeking.  You noticed that most of the systems collect redundant information and one is actually from 1980. Nobody actually knows how it works and what exactly is doing. What is clear is that if they try to turn it off, 50% of their systems stop working.

You manage to restrict the list to two systems that may provide the relevant information to you. Proper access to the data need to be programmed as there is not an existing module that is capable to do what you are envisioning. By the way, the IT Department thinks that it is not a particularly difficult task (really?!? Mmmm sound suspicious).

The systems are, University of Nowhere Student CRM that offer the following information:

• Retrieve the list of Unique ID (ANR) of all the students
• Retrieve the email associated to a particular Unique ID (ANR). All the information related to a student’s profile (address, phone number etc etc) are there as well.

And the system, University of Nowhere ACME digital learning with the following information:

• Retrieve the list of classes that are currently offered by the university
• Retrieve the list of students (with their unique ID or ANR) that are following a particular class

3 – The Mission of the Business Process Integrator

Your mission (should you choose to accept it) is to understand and model the needs of University of Nowhere. You will give to all the stakeholders (students, professors, ACME Social) what they need for implementing the foreseen business agreement. In addition, the rector magnificus need a clear road map to present the board for securing the budget for the project. Due to your extensive experience in Business Process Integration you know what the stakeholders need. You intend to produce is a document that summarizes the state of the art the the planned actions. In particular the document should contains :

• One or more Use Case diagrams that describe the functionalities of the BPI solution that the University of Nowhere should support. You also count of the fact that you can explain each Use Case using natural language (English) to make them simple and more readable. They key challenge in this task is to try to identify all the actors involved.
• One or more Activity Diagrams for illustrating the dynamic of the Use Cases and model the overall end-to-end process. This Diagram will give you the possibility to specify the internal and external systems involved as well as their interactions. 
• An UML class diagram describing all the concepts used among all the selected processes and systems. Once you will be able to specify all the attributes and the methods of the classes they IT Department will know exactly what to do.
• A set of Sequence Diagrams that leverage the Use Cases and the Class Diagram in order to clearly specify: (i) how the system interacts and (ii) how your solution will implement the process as defined by the business requirements.

Take home message for this example of business process integration

This is just an example of business process integration with a “big data flavor”. It is fictional and represent a simplified use case. Nevertheless is not trivial and still represents relatively well a real cases. You can have a look at the syllabus of BPI for more information.

More information regarding the diagrams that we envision is available at this link.

[1] Possible (but this is fictional) real life examples include: Facebook, Twitter, LinkedIn, Google, Academia, Researcher

[2] Possible (but this is fictional) real life examples include: Bol or Amazon or eBay

The post BPI: an Example of Business Process Integration. (Big Data Flavor) appeared first on Francesco Lelli.

• A Computer Language like Java, C/C++, PhP or Python ..
• A human language like English, French, Italian, German, Spanish, Chinese, Dutch….
• A Modelling Language like UML, BPMN …

In the end the main question that we all have to answer for our self is: “is it worth it?”

As I find myself teaching Computer Languages and Modelling Languages I had to deal with this question and I found my personal way to reconcile both:

• the pain of learning a language
• the gains that you will get if you decide to go forward.

In this particular post, instead of trying to explain what are my motivations I will limit myself to recommend you the following movie where a linguist works with the military to communicate with alien lifeforms after twelve mysterious spacecraft appear around the world.

Below you can have a look at the trailer:

According to Wikipedia:

Arrival is a 2016 American science fiction film directed by Denis Villeneuve and written by Eric Heisserer. It is based on the 1998 short story “Story of Your Life” by Ted Chiang and stars Amy Adams, Jeremy Renner, and Forest Whitaker. The film follows a linguist enlisted by the U.S. Army to discover how to communicate with aliens who have arrived on Earth, before tensions lead to war.

As I do not intend to give you any spoiler and ruin your watching of the movie I will limit myself to say that will be a nice watching. Independently of understanding the importance of learning a new language, I am sure that you will enjoy it.

The importance of #learning learning new #languages. It does not matter if is with Computer, Humans or Aliens! #LanguageLearning
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More information on:

• IMDB: https://www.imdb.com/title/tt2543164/
• Wikipedia:https://en.wikipedia.org/wiki/Arrival_(film)

If you find yourself in a rainy week-end without much to do…. Give it a try!

Hopefully after watching it you will enjoy a bit more studying UML in Business Process Integration!

The post Importance of Learning a New Language: Arrival 2016 appeared first on Francesco Lelli.

In 1997 UML was adopted as a standard by the Object Management Group (OMG), and has been managed by this organization ever since. In 2005 UML was also published by the International Organization for Standardization (ISO) as an approved ISO standard.

Use Cases, Class and Activity Diagrams are not the only diagram of UML but they are the most commonly used in both Business and Computer Science domains.

UML Diagrams: a mini-tutorial

Let’s start with a recap of what they are (courtesy of Lucidchart ) :

Use Cases Diagram:

Class Diagrams:

Sequence Diagrams:

Tools for writing UML Diagrams

Argo UML  

http://argouml.tigris.org/

Free and Open source. Is a stand alone java based application that you have to install in your computer.

ECLIPSE Plug-in

https://marketplace.eclipse.org/content/uml-designer

Use this tool only if you are familiar with Eclipse. It is an advanced tool and also support reverse engineering of code. So, in the case where you have just to design functionalities is a bit of an overkill.

Rational Rose

https://en.wikipedia.org/wiki/IBM_Rational_Rose_XDE

This tool (developed IBM) is extremely sophisticated and support automatic deployment of models to productions.

Web based resources for drawing UML:

• https://www.lucidchart.com
• https://cawemo.com
• https://about.draw.io

Simple to use and 100% web based. The free license should cover the majority of your basic needs. It is not the only one however their basic license is one of the most comprehensive.

Microsoft Visio

https://products.office.com/en/visio/flowchart-software

Is is a comprehensive tool for all possible designs and support UML as well. Students should have a free or almost free license

Example of UML diagrams and case studies

Here you can find a curated list of examples of various diagrams:

https://www.uml-diagrams.org/index-examples.html

There you will find a set of simple but complete use cases that could help you in familiarizing with the language. Additional resources are also available at tutorial point:

https://www.tutorialspoint.com/uml/index.htm

Would you like get some #KNOWLEDGE of UML? This is a curated set of resources that could help. #softwaredevelopment #Engineering
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