How Classes are Found

How Classes are Found: "How the Java Launcher Finds Classes

The Java launcher, java, initiates the Java virtual machine. The virtual machine searches for and loads classes in this order:

Bootstrap classes - Classes that comprise the Java platform, including the classes in rt.jar and several other important jar files.
Extension classes - Classes that use the Java Extension mechanism. These are bundled as .jar files located in the extensions directory.
User classes - Classes defined by developers and third parties that do not take advantage of the extension mechanism. You identify the location of these classes using the"

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