Built in JAVA Classes are Predefined Classes. Predefined Class means those Classes which are not created by us. (In simple words we can say JAVA Virtual Machine provide some classes with features) that classes are called as Predefined JAVA Classes.
for example :
there are thousands of classes are available in JAVA World. Each and every class have its own property.
String class is used to create normal Strings. if you don’t know what is string, then don’t need to worry about it I will explain this in Strings chapter. for now “hello world” everything written in double quotes ("") is called as String. if you have some basic knowledge about C or C++ language then you will understand what is String. And in String class it have some other features like :
So this is just basic knowledge about what are Built in classes, and why we need built in classes.
We need built in Classes in every Programming language, Programming language without Classes are incomplete. Below are cases when you need Built in classes to complete out task.
and so on. So this is real definition of Built in classes in every Programming language.
Those classes which are created by us. Or those classes which we created to reuse in future, is called as User defined classes.
for example : Hello,Abc,Demo etc. these classes are not defined by JAVA itself. we made these classes to use in future or combine everything in a single class.
Let see how to create a simple class :
this is syntax of creating class in JAVA. I will explain in detail about creating class in JAVA.