For the class diagram, let's imagine the following setting—we want our users to be able to download some data from a server and get it de-serialized in the form of objects. The server returns our data in encoded form, so we should decode it first, then parse it, and finally return the right objects. This involves many operations and makes things complicated. That's why we use a facade design pattern:
When clients use the preceding application, they will just have to interact with the DataReader. Internally, it will take care of downloading, decoding, and deserializing the data.
