Again in the pits of the coding jungle I discovered that we were breaking the Singleton design pattern. Basically what we had were public default constructors. This of course would allow anyone or any dynamic assembly loader to create a new instance of what should be a unique object!
To solve this I decided to augment our dynamic loading class to look for an attribute: [SingletonAttribute] or [Singleton]. If it finds this, then it will look for [SingletonInstance] that should be on a public static getter.
Old code:
public class NotQuiteSingleton
{
private static NotQuiteSingleton _instance = new NotQuiteSingleton();
public static NotQuiteSingleton Instance
{
get
{
return _instance;
}
}
/// REALLY BAD!
public NotQuiteSingleton()
{
}
}
New code:
[Singleton]
public class AuthenticSingleton
{
private static AuthenticSingleton _instance = new AuthenticSingleton();
[SingletonInstance]
public static AuthenticSingleton Instance
{
get
{
return _instance;
}
}
// Ahhhh... much better...
private AuthenticSingleton()
{
}
}
Enjoy,
John
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