java variable types code example

Example 1: Variables in java

// instance variable in java example
public class InstanceVariableDemo
{
   // instance variable declared inside the class and outside the method
   int c;
   public void subtract()
   {
      int x = 100;
      int y = 50;
      c = x - y;
      System.out.println("Subtraction: " + c);
   }
   public void multiply()
   {
      int m = 10;
      int n = 5;
      c = m * n;
      System.out.println("Multiplication: " + c);
   }
   public static void main(String[] args)
   {
      InstanceVariableDemo obj = new InstanceVariableDemo();
      obj.subtract();
      obj.multiply();
   }
}

Example 2: primitive data types in java

/* 
	Java Data Types
There 2 Types Of Data Types In Java
1) Primitive -> byte, char, short, int, long, float, double and boolean.
2) Non-primitive -> (All Classes) -> String, Arrays etc.

Type	Size	Stores
byte	1 byte	whole numbers from -128 to 127
short	2 bytes	"" -32,768 to 32,767
int	    4 bytes	"" -2,147,483,648 to 2,147,483,647
long	8 bytes	""-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
float	4 bytes	fractional numbers; for storing 6 to 7 decimal digits
double	8 bytes	fractional numbers; "" 15 ""
boolean	1 bit	true or false values
char	2 bytes	single character/letter or ASCII values
*/

Example 3: Variables in java

// static variable in java example
public class StaticVariableExample
{
   // static variable
   static int a = 0;
   public void add()
   {
      a++;
   }
   public static void main(String[] args)
   {
      StaticVariableExample obj1 = new StaticVariableExample();
      StaticVariableExample obj2 = new StaticVariableExample();
      obj1.add();
      obj2.add();
      // both objects are sharing same copy of static variable
      System.out.println("Object 1 value is: " + a);
      System.out.println("Object 2 value is: " + a);
   }
}

Example 4: java variables

/*
##	Variable
- Container which holds the value while the Java program is executed. 
- Assigned with a data type. 
- Name of memory location. 

##	There are three types of variables in java: 
1) Local variable 
2) Static (or class) variable 
3) Instance variable
*/