Question

I am attempting to have a ReportHandler service to handle report creation. Reports can have multiple, differing number of parameters that could be set. In the system currently there are several different methods of creating reports (MS reporting services, html reports, etc) and the way the data is generated for each report is different. I am trying to consolidate everything into ActiveReports. I can’t alter the system and change the parameters, so in some cases I will essentially get a where clause to generate the results, and in another case I will get key/value pairs that I must use to generate the results. I thought about using the factory pattern, but because of the different number of query filters this won’t work.

I would love to have a single ReportHandler that would take my varied inputs and spit out report. At this point I’m not seeing any other way than to use a big switch statement to handle each report based on the reportName. Any suggestions how I could solve this better?

Answer 1

From your description, if you’re looking for a pattern that matches better than Factory, try Strategy:

Strategy Pattern

1. Your context could be a custom class which encapsulates and abstracts the different report inputs (you could use the AbstractFactory pattern for this part)
2. Your strategy could implement any number of different query filters or additional logic needed. And if you ever need to change the system in the future, you can switch between report tools by simply creating a new strategy.

Hope that helps!