Day7: Type of Variable in Java

 Type of Variable in Java

In Java we've three type of variable:
  1. Local Variable
  2. Instance Variable
  3. Static Variable

1)Local Variable

These are those variable which are declared inside a method and they do not have any default value. so, it is an error to use an uninitialized local variable -

class Demo
{
public static void main(String [ ] args)
{
int a = 30;                   //Local Variable
System.out.println("The value of a is "+a);
}
}

2)Instance Variable

These are those variable which are declare at the class level and they have default values alloted by java which are :
            byte, short, int ----> 0
            char ----> '\0'
            float ----> 0.0f
            double ----> 0.0
            long ----> 0L
            boolean ----> false
            referance ---> null

class Demo
{
        int a;            //Instance Variable 'a'
public static void main(String [ ] args)
{
System.out.println("The value of a is "+a);
}
}

3)Static Variable

They also are variable declared at the class level but prefix with keyword static. They have same default value of instance variable.
class Demo
{
        static int a;            //static Variable 'a'
public static void main(String [ ] args)
{
System.out.println("The value of a is "+a);
}
}

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