Php design pattern Adapter (Adapter pattern)

Converts an interface of a class to another interface that the customer wants. classes that are originally incompatible and cannot work together can work together. The code is as follows:
/**
* Adapter mode
*
* Convert an interface of a class to another interface that the customer wants. classes that are originally incompatible and cannot work together can work together.
*/

// This is the original type
Class OldCache
{
Public function _ construct ()
{
Echo "OldCache construct
";
}

Public function store ($ key, $ value)
{
Echo "OldCache store
";
}

Public function remove ($ key)
{
Echo "OldCache remove
";
}

Public function fetch ($ key)
{
Echo "OldCache fetch
";
}
}

Interface Cacheable
{
Public function set ($ key, $ value );
Public function get ($ key );
Public function del ($ key );
}

Class OldCacheAdapter implements Cacheable
{
Private $ _ cache = null;
Public function _ construct ()
{
$ This-> _ cache = new OldCache ();
}

Public function set ($ key, $ value)
{
Return $ this-> _ cache-> store ($ key, $ value );
}

Public function get ($ key)
{
Return $ this-> _ cache-> fetch ($ key );
}

Public function del ($ key)
{
Return $ this-> _ cache-> remove ($ key );
}
}

$ ObjCache = new OldCacheAdapter ();
$ ObjCache-> set ("test", 1 );
$ ObjCache-> get ("test ");
$ ObjCache-> del ("test", 1 );