Flyweight

Flyweight is an object without any state. The name comes from it being very light. If you've been reading either one of the two previous chapters, you might already be thinking of a type of object that should be very light: a data class. But a data class is all about state.

So, is the data class related to the Flyweight design pattern at all?

To understand this design pattern better, we need to jump back in time some twenty years. Back in 1994, when the original Design Patterns book was published, your regular PC had 4 MB of RAM. During this period, one of the main goals of any process was to save that precious RAM, as you could fit only so much into it.

Nowadays, some cellphones have 8 GB of RAM. Bear that in mind when we discuss what the Flyweight design pattern is all about in this section.

Having said that, let's see how we can use our resources more efficiently, as this is always important!

Being conservative

Imagine we're building a...