bootstrap loader:
*loads primordial classes and core module system classes.
Base module loader
*loads non-core module system classes and all other classes in the base module.
ref:
Project Jigsaw: Module Class Loading and Bootstrapping
how the ‘java(java launcher)‘ finds classes:
the vm searches for and loads classes in the order of:
a,bootstrap classes,which compriss the java platform,including the classes in the rt.jar and other important .jar files.
b,extension classes,which use the java extension mechanism,bundled as .jar files in the “lib/ext” extension directory.
c,user(defined) classes,which were definded by developers and third parties that does not take advantage of the extension mechanism(identify these classes using the -classpath option).
原文:http://www.cnblogs.com/listened/p/3674680.html