Java: What is the difference between runnable jar library handling options in Eclipse?

When exporting a Java app into a Runnable Jar, there are three options in Eclipse. What is the difference?

Answer by Michael:

1. Extract required libraries into JAR
   Extracts the actual .class files from the libraries your app uses and puts those .class files inside the runnable JAR. So, the runnable JAR will not only contain the .class files of your application, but also the .class files of all the libraries your application uses.
   
   
2. Package required libraries into JAR
   Puts the actual JAR files of the libraries into your runnable JAR. Normally, a JAR file within a JAR file cannot be loaded by the JVM. But Eclipse adds special classes to the runnable JAR to make this possible.
   
   
3. Copy required libraries into sub folder next to JAR
   Keeps the library JARs completely separate from the runnable JAR, so the runnable JAR will only contain the .class files of your application.

Ref:
eclipse - What is the difference between runnable jar library handling options? - Stack Overflow