The purpose of the app to be built is managing information about
movies. The app deals with just one object type: Movie, as
depicted in the following class diagram.
In this model, the following constraints have been expressed:
Due to the fact that the
movieIdattribute is declared to be the standard identifier ofMovie, it is mandatory and unique.The
titleattribute is mandatory, as indicated by its multiplicity expression [1], and has a string length constraint requiring its values to have at most 120 characters.The
releaseDateattribute has an interval constraint: it must be greater than or equal to 1895-12-28.
Notice that the releaseDate attribute is not
mandatory, but optional, as indicated
by its multiplicity expression [0..1]. In addition to the constraints
described in this list, there are the implicit range constraints defined
by assigning the datatype PositiveInteger to
movieId, NonEmptyString to title,
and Date to releaseDate.
You can use the sample data shown in Table 8.2 for testing your app.
The purpose of the app to be built is managing information about
countries. The app deals with just one object type:
Country, as depicted in the following class diagram.
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In this model, the following constraints have been expressed:
Due to the fact that the
nameattribute is declared to be the standard identifier ofCountry, it is mandatory and unique.The
nameattribute has a string length constraint requiring its values to have at least 3 and at most 50 characters.The
populationattribute is mandatory, as indicated by the multiplicity expression [1] appended to the attribute name.The
lifeExpectancyattribute is also mandatory and has an interval constraint: its values must be less than or equal to 100.
Notice that the militaryExpenditure attribute is not
mandatory, but optional, as indicated
by its multiplicity expression [0..1].
In addition to the constraints described in this list, there are
the implicit range constraints defined by assigning the datatypes
NonEmptyString to name,
PositiveInteger to population,
PositiveDecimal to lifeExpectancy and
Percentage to militaryExpenditure (hint: a
percentage value is a decimal number between 0 and 100). In our Java
example app, such property constraints were coded in the entity class by
using the Bean Validation API.
You can use the sample data shown in Table 8.3 for testing your app.