What are classes in Java

First things that comes in mind are
  • A class is a blueprint from which objects are created.
  • They are wrappers and have everything inside them e.g Functions/Methods/Variables etc.
  • They can be public or default but not private or protected.
  • Each Class has a name, and may belong to a package.
  • A class can have both static and non static methods and variables.
  • A class can not be static (however inner classes can be).
Definition
A class is the blueprint from which individual objects are created. A class containes
  • A main method marked as public static void and taking an array of String arguments.
  • Instance variables that are inside a class but outside all function.
  • Local variables that are inside a function. Their scope is limited to the function only.
  • Member functions that can be either static, non static or final or final static.
  • A package declaration, this is important for grouping same type of classes together.

package com.ekiras.demo;

public class HelloWorld{

  int instanceVarible = 1;

  public static void main(String args[]){

    System.out.println("HelloWorld");
  }

  public void method(){
    
    String localVariable = "Hi";
  } 

}

A simple class may look like the one shown above.

Access specifiers of a class
A class can have public or default access specifier. The class can not be private or protected.

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