Java Factory & Singleton: Combined Benefits

Combining the factory pattern and singleton pattern can bring the following benefits:

1. Flexibility: The factory pattern allows for the creation of different types of objects as needed, while the singleton pattern ensures that only one instance exists. By combining the two, object creation can be unified throughout the system while also guaranteeing that only one instance exists.
2. Reduce coupling: the factory pattern encapsulates the object creation logic in a factory class, allowing clients to simply retrieve the desired objects through the factory class without having to worry about the specifics of the creation process. The singleton pattern can prevent frequent object creation, thereby reducing the coupling between objects.
3. Improving performance: Singleton design pattern can reduce the number of object creations, saving system resources. Combined with the factory pattern, we can cache already created object instances in the factory class, further enhancing performance.
4. Convenient management: By combining the factory pattern and singleton pattern, the creation and lifecycle of objects can be managed in a unified way. When there is a need to modify the logic of object creation, only the factory class needs to be modified, without the need to modify the client code.

In conclusion, combining the factory pattern with the singleton pattern can offer advantages such as flexibility, reduced coupling, improved performance, and convenience in management. This combination can better organize and manage the creation and use of objects in large projects.