Based on the proposed use case diagram, the group would like to present the structural design of the application. Figure 1 is the class diagram consists of 12 classes including User, Nationality, Creditcard, CreditcardCompany, Organisation, Embassy, Country, City, Location, Rating, Route, Weather.

Figure 1 The class diagram of the application

The class diagram is divided into three parts:

1) Emergency (Figure 2): The classes store essential information, including the contact of embassy and Credit Card Company. The classes related are User, Nationality, Creditcard, CreditcardCompany, Organisation, Embassy.

Class User records the user details and operations and the classes contains essential information, including the contact of embassy and Credit Card Company. Users can store their basic card details in the application, and it links to corresponding cardlost hotlines when there is emergency. The application does not store any personal details (eg. credit card number) to reduce the privacy risks.

Figure 2 the classes related to emergency situations

2) Generate safety Routes (Figure 3): Class Country contains a list of City class. Each route stores a sequence of locations as checkpoints of the route. Users can rate a route, a location after they finish the route.

Figure 3 the classes related to generate safety routes

3) Weather integration (Figure 4): the weather information is considered while generating every safety routes. The Weather Class contains functions for retrieving specific weather information.

Figure 4 the classes related to weather

Written by Po Ting Tse

This post represents that the group has chosen appropriate economic and social Contextual Factors that directly link to the marking criteria, and are vital to understanding what requirements app design has. This is based on market analysis, evaluation, and previous engineering decisions. There is evidence that research has been chosen intelligently (by reference to literature and analysis) to produce a conclusion of professional quality, leading to a successful product. 

This post additionally represents Engineering and Design decisions. These are based on the Contextual Factors and literature review which the group have tailored the product to incorporate. This means that the activity diagram has considerable research, fluent design and well planned engineering steps to achieve this. This post illustrates how and why the product has been influenced in its design and engineering, and shows how the engineering of the app will solve problems through multiple class diagrams. 

In addition, this post illustrates considerable use of media, innovation and creativity. This is apparent through applying Contextual Research, Design steps and engineering guidelines to produce class diagrams which contribute to the product, summarises what the product does, and provides visualisations that align with the target market. 

Furthermore this post features the use of different types of media evident in the class diagrams.