JAVA CLASSES

CLASSES

—An object is an instance of a class.

—A class is a template or blueprint from which objects are created.

—An object is a real-world entity.

—An object is a runtime entity.

—The object is an entity which has state and behavior.

—The object is an instance of a class.

CLASS DECLARATION

Syntax to declare a class:

class <class_name>

{  

    field;  

    method;  

}  

INSTANCE VARIABLE IN JAVA

—A variable which is created inside the class but outside the method is known as an instance variable.

— Instance variable doesn't get memory at compile time.

— It gets memory at runtime

—when an object or instance is created.

— That is why it is known as an instance variable.

NEW OPERATOR

—The new keyword is used to allocate memory at runtime.

— All objects get memory in Heap memory area.

OBJECT CREATING IN NEW KEY WORD

public class obj

{

  public void disp()

  {

  System.out.println("method calling");

  }

  public static void main(String args[ ])

  {

  obj a=new obj();

  a.disp();

  }

}