When do you need to create a destructor?

In class design, developers often struggle with whether they need to create destructors. However, it is crucial to understand the proper usage of destructors.

Reasons for creating destructors

Usually the destructor is only required if the class holds expensive unmanaged resources such as database connections or file handles. In this case, the destructor is responsible for freeing these resources when objects are no longer needed, ensuring proper cleaning.

Disadvantages of destructors

Although destructors are useful in certain specific situations, they also present some challenges and potential problems:

• Asynchronous execution: The destructor runs on a separate thread and may cause deadlock if it is not handled properly.
• Unhandled exception: The exception thrown in the destructor cannot be caught and may lead to unpredictable behavior.
• Constructor - Destructor Interaction: Destructor may be called while the constructor is still executing, which may cause object initialization issues.
• Object Resurrection: The destructor may "resurrect" an object so that it survives again after being marked as deleted.
• Unpredictable ending: cannot guarantee that the destructor will be called; the termination process may be delayed or unexpectedly skipped.

Alternative to destructor

In most cases, it is recommended to use disposable patterns instead of relying on destructors. Disposable mode provides a clearer way to free resources, making it easier to ensure cleanup without destructor-related drawbacks.

When should I consider using destructor

If you are sure that your class needs to manage a large number of unmanaged resources and that the disposable pattern does not apply, you may need to create a destructor. However, it is important to operate with caution and fully understand the complexity and limitations of destructors.