What is observer next

An observable object can have one or more observers . An observer may be any object that implements interface Observer.

The observer pattern is a software design pattern in which an object, named the subject, maintains a list of its dependents, called observers, and notifies them automatically of any state changes, usually by calling one of their methods .

In Java Edition, an observer detects changes in its target’s block states, or the breaking or placing of a block (i.e. changes in its block state, but not its block entity data). This means that changes like the age of crops can be detected because they are part of the block states.

Observable is used to create subclasses that other parts of the program can observe . When an object of such subclass undergoes a change, observing classes are notified. The update( ) method is called when an observer is notified of a change.