Masaryk university
Faculty of Informatics
Conceptual modeling using HIT method in
Visual Paradigm for UML tool
J´an Demo, Marek Winkler, Michal Oˇskera
c FI MU, September 28, 2011
1 Introduction
This document is a guide how to use Entity-Relationship diagram (ERD)
of Visual Paradigm for UML (VP-UML) for creation of conceptual models
according to the HIT method. The knowledge of basic concepts of HIT
method is assumed, i.e. this document is not about HIT method itself,
it explains how its key concepts are represented by ERD elements in this
particular modeling tool.
VP-UML is available at FI MU under the Academic License Standard Edition,
for more information refer to http://kore.fi.muni.cz:5080/wiki/
index.php/Tools#Visual_Paradigm. It is also possible to download and
use viewer or community edition directly from the producer of VP-UML at
http://www.visual-paradigm.com/.
This document covers the following topics:
• creation of a blank model,
• setting of conceptual type of a model,
• modeling entities of basic types,
• defining entities and relationships,
• modeling supertype-subtype relationships,
• other useful settings of VP-UML
2 Creation of a blank model
To create a blank model, a new ERD has to be created in VP-UML.
Figure 1: Creation of new ERD – model
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3 Setting of conceptual type of a model
Newly created ERD may be one of the following types:
• conceptual,
• logical,
• physical.
The type of ERD can be selected under the menu item Data Model in
the context menu of the ERD. The context menu pops up after right clicking
on the canvas of the ERD (see Figure 2). It is not surprising that the right
choice is Conceptual.
Figure 2: Setting type of a model
4 Modeling entities of basic types
The entities of basic types are modeled in VP-UML as follows:
• kernel entities are represented by the default entity representation in
VP-UML,
• associative entities are distinguished by the assoc stereotype; the stereotype
can be selected by right-clicking on an already created entity →
Stereotypes → assoc (see Figure 3),
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• characteristic entities are distinguished by characteristic stereotype;
the selection of stereotype is analogous to the selection of assoc stereo-
type.
Figure 3: Setting the assoc stereotype of an associative entity
If the requested stereotype is not available in menu, it is necessary to
define it:
1. to edit stereotypes click on Tools → Configure Stereotypes...,
2. in Model elements tree select model element that should be stereotyped,
in this case it will be always Entity Relationship → Entity (see
Figure 4),
3. press Add... button and in opened form fill in the name of the stereotype,
for example assoc, and documentation, for example: Denotes that
the Entity is an Associative entity. (Figure 5).
Figure 6 shows how the associative entity with the appropriate stereotype
looks like.
5 Defining entities and relationships
The HIT method of conceptual modeling requires all visual model elements,
i.e. both entities and relationships, to be appropriately defined. The semantics
shall be written in Documentation text field in General tab within
specification dialog of the corresponding model element. This can be achieved
in two ways:
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Figure 4: Editing stereotypes
• right-click on entity/relationship to be defined → Open Specification
(Enter) and write semantics in Documentation multiline text field,
• it may be more comfortable to use the toolbar window Documentation
in some cases. This window is permanently visible and its content is
bounded to the currently selected model element. The window can be
made visible
– through menu View → Panes → Documentation,
– or key shortcut Ctrl+Shift+U.
When writing semantics of a model element, for example An object of
type (#Customer) is every ... , it is recommended to use function Add Model
Element (see figure 7) for writing the name of the element, in this example
Customer. The advantage is that if the model element is renamed the new
name is automatically updated in all definitions where the renamed element
was referred.
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Figure 5: Editing stereotype assoc
Figure 6: Stereotyped associative entity
6 Modeling supertype-subtype relationship
The supertype/subtype (or general/specialized) relationship can be modeled
in VP-UML using the following steps:
1. create 1:1 relationship in direction from intended supertype to intended
subtype,
2. in the context menu of the created relationship check that this is an
identifying relationship (→ Identifying),
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Figure 7: Using Add Model Element function to write name of a model
element
3. in the same menu check that this is a subtype kind of relationship
(→ Subtype).
Figure 8 shows an example of a supertype/subtype relationship, where
the Entity B is a subtype (or a specialization) of the Entity A.
Figure 8: Example of supertype/subtype notation in VP-UML
Unfortunately, VP-UML (version 8.1) supports modeling of generalization
sets in Class diagrams only1
. Therefore, you may model supertype/subtype
relationships as separate connections without grouping them into generalization
sets.
1
see http://www.visual-paradigm.com/support/documents/vpumluserguide/94/
299/7190_drawingclass.html
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7 Other useful settings of VP-UML
7.1 Spell checking
If the model elements and their definitions have not been written in English,
it is recommended to switch off Spell checking for better readability:
• Tools → Options,
• in Options window click on the left side on the Spell Checking item,
• uncheck the Enable Spell Checking check box.
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