Use a scenario based analysis the objects attributes

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Use a scenario-based analysis. The objects, attributes and methods in each scenario are identified. 13 Chapter 7 Design and implementation 7.1.3 Weather station description (continued) A weather station is a package of software controlled instruments which collects data , performs some data processing and transmits this data for further processing. The instruments include air and ground thermometers , an anemometer , a wind vane, a barometer and a rain gauge. Data is collected periodically. When a command is issued to transmit the weather data, the weather station processes and summarises the collected data. The summarised data is transmitted to the mapping computer when a request is received. 14 Chapter 7 Design and implementation 7.1.3 Weather station object classes (continued) Object class identification in the weather station system may be based on the tangible hardware and data in the system: Ground thermometer, Anemometer, Barometer Application domain objects that are hardware objects related to the instruments in the system. Weather station The basic interface of the weather station to its environment. It therefore reflects the interactions identified in the use-case model. Weather data Encapsulates the summarized data from the instruments. 15 Chapter 7 Design and implementation 7.1.3 Weather station object classes (continued) 16 Chapter 7 Design and implementation 7.1.4. Design models Design models show the objects and object classes and relationships between these entities. Static models describe the static structure of the system in terms of object classes and relationships. Dynamic models describe the dynamic interactions between objects. 17 Chapter 7 Design and implementation 7.1.4 Examples of design models (continued) Subsystem models that show logical groupings of objects into coherent subsystems. Sequence models that show the sequence of object interactions . State machine models that show how individual objects change their state in response to events . Other models include use-case models, aggregation models, generalisation models, etc. 18 Chapter 7 Design and implementation
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