Provides a basic class for programming using the Java programming language. The most important class of 1> is Object(which is the root of the class hierarchy ) and class (its instance represents a class in the running application). 2> It is often necessary to represent the value of a base type as an object. The wrapper class Boolean, Character, Integer, Long, Float, and Double are used for this purpose. For example, an object of type double contains a field of type double, which means that if a value is referenced, the value can be stored in a variable of the reference type. These classes also provide a number of methods for converting base values, and support some standard methods, such as Equals and hashcode. The Void class is a non-instantiated class that maintains a reference to a class object that represents the base type void. The 3> class math provides common mathematical functions, such as sine, cosine and square root. Similarly, class string and StringBuffer provide common string manipulation. The 4> class ClassLoader, process, Runtime, SecurityManager, and system provide dynamic loading of management classes, external process creation, host environment queries (such as time), and security policy enforcement. The 5> class Throwable contains objects (§14.16) that may be thrown by a throw statement. Throwable subclasses represent errors and exceptions.
Classification of Java.lang Bags
