This guide shows how to locate a jar’s source code in Eclipse, edit it (e.g., add a log statement), export the modified project as a new jar—using the FatJar plugin when third‑party dependencies exist—and replace the original jar in a Java application to see the changes.
This article dissects how a simple Spring Boot Hello World application launches, walks through the runtime call stacks, explains the FatJar packaging and custom ClassLoader, and reveals how @RestController classes are automatically registered with the embedded Tomcat server.
This article dives deep into SpringBoot’s inner workings, tracing a simple HelloWorld application from its main method through the startup call stack, FatJar packaging, custom ClassLoader behavior, and automatic controller registration via annotations, revealing why the framework feels both lightweight and monstrously complex.
