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Class Loading while running JVM

  • The Order is
    • 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 -classpath option on the command line (the preferred method) or by using the CLASSPATH environment variable. 
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