Author Topic: How we draw a usecase diagram from a case study?  (Read 2167 times)

1171948312

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Re: How we draw a usecase diagram from a case study?
« Reply #15 on: February 14, 2018, 06:50:21 am »
1.Read the case study thoroughly 2-10 times.
2.Understand the actors and actions who are involved in the case study.
3.Write down the primary actors(End User/who interacts with the system) and secondary actors(On whom system dependent on)and the actions involved in the case. Generalize actors and actions involved in the case.
4. Draw a system boundary- usecase
5.Place the primary actors on the left-hand side of the system boundary.
6.Place the secondary actors on the right side.
7. Place the Actions inside the system boundary. Connect the actors and actions in the system and connect the actions which are dependent on secondary actor.
8.Hence we draw Usecase diagram.

1170944412

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Re: How we draw a usecase diagram from a case study?
« Reply #16 on: March 10, 2018, 12:58:54 pm »
Use case diagrams are used to describe the functionality of a system from a top-down perspective. They represent only the positive flow and all the available functionality of the system are shown. There are essentially four major elements of UCDs
The actors, the system, the use cases and the lines that represent the relationship between these elements.
We use the following rules to draw use case diagram
•   Information that we do not model in the use case diagrams are
             Architecture names (2 tier, 3 tier, client server etc)
             Names of the systems (laptop, desktop)
             Brand names (HP, Lenovo etc.)
             Technology used (java, .net etc.)
             Networks (LAN, WAN)
             Databases (SQL, MySQL, etc.)
•   Differentiate between information and actions
•   Write all sequence of actions
•   Try to identify the actors performing the above mentioned actions
•   Try to differentiate between essential use cases and supporting use cases
•   Try to identify some modules with respect to functionality or usage
•   Try to identify the relationships appropriately between the identified actors and the use cases
« Last Edit: March 10, 2018, 01:01:15 pm by 1170944412 »

1180650901

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Re: How we draw a usecase diagram from a case study?
« Reply #17 on: March 25, 2018, 11:07:35 pm »
First and last
Read the case study 2 -3 times because that will give you a picture .

In a very simple or layman :

1. Mark primary actors column
2. Secondary actors column
3. supporting use case
4. essential  use case

Then try to relate it with the case study

1172831810

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Re: How we draw a usecase diagram from a case study?
« Reply #18 on: April 07, 2018, 04:59:16 pm »
The following checklist shows the steps necessary for the construction of use case diagrams from the external view.

  • Collect information sources—How am I supposed to know that?
    Identify potential actors—Which partners and customers use the goods and services of the business system?
    Identify potential business use cases—Which goods and services can actors draw upon?
    Connect business use cases—Who can make use of what goods and services of the business system?
    Describe actors—Who or what do the actors represent?
    Search for more business use cases—What else needs to be done?
    Edit business use cases—What actually has to be included in a business use case?
    Document business use cases—What happens in a business use case?
    Model relationships between business use cases—What activities are conducted repeatedly?
    Verify the view—Is everything correct?


Satish kumar Gajula

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Re: How we draw a usecase diagram from a case study?
« Reply #19 on: April 24, 2018, 04:46:58 pm »
Steps to follow to draw a Use Case diagram from a case study:
1.   Information which we Do Not model in Use Case diagrams are
a)   Name of the systems (Laptops, Desktops, Workstations),
b)   Architectures (2 Tier, 3 Tier, n Tier, Client Server),
c)   Databases Names (DB2, SQL Server, My SQL),
d)   Networks (LAN, WAN, Internet),
e)   Brand Names (HP, Lenovo, Wipro, Sony)
f)   Technology Names (Java, .Net, Mainframes)
2.   Differentiate information against actions
3.   Write all sequence of actions
4.   Try to find out which actor is performing the above action
5.   Try to identity Essential Use Cases and Supporting Use Cases
6.   Try to identity some modules with respect to functionality or usage
7.   Try to draw the relationships appropriately between the identified actors and use cases.

1180654601

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Re: How we draw a usecase diagram from a case study?
« Reply #20 on: June 06, 2018, 10:26:24 pm »
The purpose of use case diagram is to capture the dynamic aspect of a system.Use case diagrams are used to gather the requirements of a system including internal and external influences. These requirements are mostly design requirements. Hence, when a system is analyzed to gather its functionalities, use cases are prepared and actors are identified.

To conclude an use case is used for;'
-Used to gather the requirements of a system.
-Used to get an outside view of a system.
-Identify the external and internal factors influencing the system.
-Show the interaction among the requirements are actors.

Steps to be followed to draw Use case Diagram;
(1) Information which we do not model in Use case diagram are:
Names of the systems (Laptops, Desktops, Work stations).
Architectures (2 Tier, 3 Tier, Client server).
Databases names (DB2, SQL Server, My SQL).
Networks (LAN, WAN, Internet).
Brand Names (Lenovo, Intel, Sony, HP).
Technology Names (Java, C++, Dot Net).
(2) Differentiate information against actions.
(3) Write all sequence of actions.
(4) Try to find out which actor is performing the above action.
(5) Try to identify essential use cases and supporting use cases.
(6) Try to find out modules with respect to functionality or usage.
(7) Try to draw the relationships appropriately between identified actors and use cases.


1183170103

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Re: How we draw a usecase diagram from a case study?
« Reply #21 on: June 15, 2018, 02:18:54 pm »
This is typically my approach ( keeping in mind the step mentioned in the book - i.e., dont model databases, tech, brand names etc)

compile actors and actions into a list. Then, you draw connectors between actors and actions. What you end up with, is a clear visual representation of the relationship between actors and actions. It's really easy after this.

The difficulty lies in identifying the actions and actors without missing anything.