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Click on first view, second view, and third view to see just three structural views derived from the composition structure. Of course there may be many other structural views as well as the three shown. Each view results from a different understanding of what is important and what unimportant about the system.
The above diagram gives a first way of structuring the example system - the construction supply process. It shows (with dotted lines) how the process could be structured into three large components to represent the roles of the three companies participating in the process. Note that some of the lines (representing flows of information or artifacts in the initial diagram) are here shown crossing the dotted lines (representing the boundaries between the companies). This indicates that these lines represent flows of information or artifacts between the companies.
The above diagram gives a second way of structuring the example system - the construction supply process. It shows (with dotted lines) how the process could be structured into three large components to represent the three stages in the supply process - choose suppliers, purchase supplies, and deliver (and pay for) supplies. Note that the boundaries between the large components cut through the rectangles representing the roles "supplier sales persons" and "buyer", thus indicating that these roles participate in more than one stage of the supply process. Note also that there is a time element to this structure, a particular supply is purchased after the supplier has been chosen but before the supply is delivered.
The above diagram gives a third way of structuring the example system - the construction supply process. It shows (with dotted lines) how the process could be structured into two large components. One of the components contains the parts of the system concerned with registering suppliers, the other the parts concerned with using suppliers. This diagram would be useful to those primarily interested in how suppliers were registered. In fact, this way of structuring the process looks rather boring as it shows only one mechanism for registration, but it would be less boring if the process had many such mechanisms (and there are such processes).
last revision: 21st June 1997