update(String desc), method is called by the subject on the observer in order to notify it, when there is a change in the state of the subject.Java Design Patterns subscribe(), method is used to ...

Observer design is a methodology in control systems engineering that involves designing an observer to estimate the unmeasurable internal states of a system based on available measurements.

This book enables you to upskill by understanding popular patterns to evolve into a proficient software developer. You’ll start by exploring the Java platform to understand and implement design ...