when I try to read the spring-integration code, I find it is essential to know spring-messaging first. some concepts are same like message channel, pollable / subscribable channel, asynchronious, integration, etc.
spring-messaging is a sub-module under spring-framework. it highly abstracts the components when two systems needs to communicate via messages.
The more design patterns we talk about, the less powerful a language is.
The more powerful a language is, the more we will use integrated features than design patterns.
list few design patterns which are really excited to use with the evolution of Java.
Reflection or runtime introspection is a powerful feature in Java. some cool features we use in Spring like copyProperties, core concepts are come from Jdk only.
Under JDK java.beans package, there are some key classes used for reflection.