Variables

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Variable is name of reserved area allocated in memory.
Example:
     int var=20; //Here var is a variable

There are three types of variables in java:
  • local variable
  • instance variable
  • static variable
Local Variable

A variable that is declared inside the method is called local variable.

Instance Variable
  • A variable that is declared inside the class but outside the method is called instance variable.
  • It is not declared as static.
Static variable

A variable that is declared as static is called static variable. It cannot be local.


Example to understand the types of variables

class A
{
  //instance variable
  int data=50;

  //static variable
  static int m=100;

  void method()
  {
    //local variable
    int n=90;
  }

//end of class
}


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