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The flyweight pattern is used for memory optimization purposes, the design pattern is usually chosen

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whenever there is a need to reduce the number of created objects.

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The reason why this pattern has been included in a structural pattern is categories because it is used

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to optimize the object structures by reducing the memory footprint of your program through creating

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a smaller number of objects.

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The scope of it is to revitalize the already created objects and to avoid creating new instances whenever

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an object is needed in our code.

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We will have an online store composed of a backend application and a client application.

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The backend application consists of the inventory back, an object which is used to process the order

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sent by the client application.

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The orders are created on the market object and the orders contain different products.

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The product object is our flyweight object, therefore we will demonstrate that whenever two orders

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are created on the same product, only one instance of that product will be created by our application.

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Therefore, reducing the memory usage of the program.

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As a general rule, this pattern is suitable only for stateless or immutable objects.

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The definition for an immutable object is whenever an object cannot be changed after its creation.

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Such an example is the string object from the job IEEPA.

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Some of the biggest weaknesses of this pattern is that it can become a bit too complex, being more

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of an optimization solution for issues related to memory management.

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Let's have a look at the implementation of this pattern in the code.