Java programming interface callback general usage code analysis

Interface callback means that the reference of the object created by the class using an interface can be assigned to the interface variable declared by the interface, and the interface variable can call the method of the interface implemented by the class. In fact, when the interface variable calls the method in the interface implemented by the class, it notifies the corresponding object to call the method of the interface. This process is called the interface callback of the object function.

General usage of java interface callback: implementing an interface is actually similar to inheriting an abstract class, except that inheritance operates at the class level, and an interface operates at the method and constant collection level. An interface is more abstract and concise than an abstract class. The implementation interface can be regarded as inheriting one or more specific methods and some constants. The specific rules of the interface will not be repeated here.