The creation of objects can be expensive so an object cache allows the toolkit to reuse certain objects instead of creating, destroying, and then recreating them. The toolkit provides a object cache each for formats and processors. An object cache is a special region of memory used to temporarily store these objects. The toolkit saves the reusable objects in the cache after using them and can then load and re-initialize them from the cache when needed. The reusable objects must implement the Cacheable interface.