variable

• a name of container on memory address that can store any value inside.
• in Java variable is two type ( instance OR local ) variables.
• instance variable scope inside class other hand local varaible scope inside function.
• instance variable have default value but local not any value

instance variable default value

[ 0 ]   integer

[ false ]   boolean

[ 0.0 ]   floating

[ ' ' ]   charactor

Declare variable

datatype vairable_name;

Assign variable

vairable_name = value;

Insalize variable

datatype vairable_name = value;

example

class Test
{
    boolean data; // instance variables
    
	public static void main(String args[])
	{
	    // local variables
	    
	    int n;  // declare
	    
	    n = 0;  // assign
	    
	    int num = 1; // insalize
	    
        System.out.println(n+" "+num+" "+data);
	}
}

output

0 1 false