Adapter Design Pattern: Plug Converter Demo

📘 Scenario:

You're traveling through Europe, and you bring along your trusty US laptop and phone chargers. But when you arrive and go to plug them in, you hit a problem — Europe uses Type C plugs with two round pins, while your chargers have the typical US Type A plug with two flat pins. There's no way to connect them directly. Luckily, you have a plug adapter with you. This small but essential device acts as a translator, converting your charger's plug shape so it fits perfectly into the European socket. Just like magic, your charger works seamlessly — all thanks to this simple interface adapter that bridges two incompatible systems.

• 💡 Europe uses Type C plugs (two round pins).
• 🔌Your charger has a Type A plug (two flat pins).

The adapter converts the interface (plug type) so the device (your charger) can work with the existing system (European socket)..

Problem:

Your US charger has a Type A plug (with flat pins), but European sockets accept only Type C plugs (with round pins). Without a direct match, you can’t connect your charger to the power supply — they are incompatible systems.

🔌 Adapter Pattern Solution:

Just like using a plug adapter, the Adapter Pattern bridges the gap between incompatible interfaces. It wraps your US charger (the client) in a compatible interface (Type C plug) so it can seamlessly connect with the European socket (the system). The underlying device remains unchanged — only the interface is adapted.

Output:

Phone starts charging...
Adapting plug...
Power supplied using US standard plug.