Converts the interface of a class into another interface that a client expects.

Lets incompatible classes work together by wrapping one with a compatible interface.

class EuropeanSocket {
  String providePower() => '220V';
}

class USPlugAdapter {
  final EuropeanSocket _socket;

  USPlugAdapter(this._socket);

  String providePower() {
    final raw = _socket.providePower();
    return '110V (converted from $raw)';
  }
}

// Usage
final adapter = USPlugAdapter(EuropeanSocket());
print(adapter.providePower()); // 110V (converted from 220V)