What are static factory methods?

• have names, unlike constructors, which can clarify code.
• do not need to create a new object upon each invocation - objects can be cached and reused, if necessary.
• can return a subtype of their return type - in particular, can return an object whose implementation class is unknown to the caller. This is a very valuable and widely used feature in many frameworks which use interfaces as the return type of static factory methods.

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