April 2018
Intermediate to advanced
910 pages
33h 21m
English
We've already seen SPI mentioned before when we looked at the Preferences class, and how the implementation is selected and loaded, but what exactly is it? The Service Provider Interface is a somewhat generic term for an interface that a third party can implement (or a class, abstract or not, that can be extended) to provide extra functionality, replace existing components, and more.
In a nutshell, the author of the target system (for example, the JDK itself in our previous example) defines and publishes an interface. Ideally, this system would provide a default implementation, but that's not necessary in all cases. Any interested third party could then implement this interface, register ...