Editing Facade pattern (section)

== Example ==
<!-- Wikipedia is not a list of examples. Do not add examples from your favorite programming language here; this page exists to explain the design pattern, not to show how it interacts with subtleties of every language under the sun. Feel free to add examples here: http://en.wikibooks.org/wiki/Computer_Science_Design_Patterns/Facade -->
<!-- In this example the author has confused a facade with a class composed of other components that it uses. This should be rewritten. -->

This is an abstract example of how a client ("you") interacts with a facade (the "computer") to a complex system (internal computer parts, like CPU and HardDrive).

=== C++ ===
<syntaxhighlight lang="c++">
struct CPU {
  void Freeze();
  void Jump(long position);
  void Execute();
};

struct HardDrive {
  char* Read(long lba, int size);
};

struct Memory {
  void Load(long position, char* data);
};

class ComputerFacade {
 public:
  void Start() {
    cpu_.Freeze();
    memory_.Load(kBootAddress, hard_drive_.Read(kBootSector, kSectorSize));
    cpu_.Jump(kBootAddress);
    cpu_.Execute();
  }

 private:
  CPU cpu_;
  Memory memory_;
  HardDrive hard_drive_;
};

int main() {
  ComputerFacade computer;
  computer.Start();
}
</syntaxhighlight>