What is the difference between a framework and a library?

A library performs specific, well-defined operations. A framework is a skeleton where the application defines the “meat” of the operation by filling out the skeleton. The skeleton still has code to link up the parts but the most important work is done by the application. Examples of libraries: Network protocols, compression, image manipulation, string utilities, regular expression evaluation, math. Operations … Read more

What is null in Java?

Is null an instance of anything? No, there is no type which null is an instanceof. 15.20.2 Type Comparison Operator instanceof At run time, the result of the instanceof operator is true if the value of the RelationalExpression is not null and the reference could be cast to the ReferenceType without raising a ClassCastException. Otherwise the result is false. This means that for any type E and R, for any E o, where o == null, o … Read more