Adapter Design Pattern Explained: Bridging Incompatible Interfaces Without Changing Code

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The Adapter design pattern solves the problem of connecting two incompatible interfaces without modifying either one, much like a travel plug converts one socket shape to another. In software, this commonly arises when a third-party library's method signatures don't match the interface your application already uses. A small adapter class sits between the two, implementing your interface on the outside while internally calling the external library's methods. This approach keeps application code clean and consistent, while isolating messy or frequently changing external dependencies inside the adapter. It is especially useful when swapping vendors, since only a new adapter needs to be written rather than updating the entire codebase.

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