8. Fundamental Classes


8.1 Overview of the java.lang Package

The java.lang package is indispensable when programming in Java. It is automatically imported into every source file at compile time. The package contains the Object class that is the superclass of all classes, and the wrapper classes (Boolean, Character, Byte, Short, Integer, Long, Float, Double) that are used to handle primitive values as objects. It provides classes essential for interacting with the JVM (Runtime), for security (SecurityManager), for loading classes (ClassLoader), for dealing with threads (Thread), and for exceptions (Throwable, Error, Exception, RuntimeException ...

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