The Plate Example

You should begin every component development with a assessment of the parameters you are working with.

Recall the example described in The Plate Example:

Determine the surface area, volume, and weight of a thick plate of a specified shape and size.

Considering step 1 and step 2 of the Basic Steps outlined above, you can identify the following information for this component.

The user must specify the shape of the plate, which is a property; it is part of the configuration but is not modifiable during execution (run time). For the given shape, the appropriate dimensions to determine the size of the plate must be specified. These dimensions must be input parameters so that new values can be passed in at run time, allowing the size of the plate to be modified. The thickness of the plate must also be an input parameter. Because weight needs to be calculated, the material must be specified. You will initially provide this as a property, choosing to not expose it to be modified at run time (you will later change it to be a parameter when you provide it through a custom datatype). There is no external application required for this component—the calculations can all be done directly in the Executor Java class. The component must provide area, volume, and weight as output parameters.

To summarize, you have the following specifications:

Properties

  • “Shape”—scalar, String (“circle,” “rectangle,” “triangle”)

  • “Material”—scalar, String (“aluminum,” “steel,” “wood”)

Parameters

  • Inputs

    • “Dimensions”—aggregate, members dynamically determined by selected “Shape”
    • “Thickness”—scalar, Real

  • Outputs
    • “Area”—scalar, Real
    • “Volume”—scalar, Real
    • “Weight”—scalar, Real

You should begin every component development with an assessment similar to this one. This allows you to know the exact quantities you have to work with when developing your wrapper classes (Editor, Executor, Handler, PostProcessor).