Numbers in Java

Numbers in Java

Numbers in Java

In java ,when we have need of a number, we use primitive data types such byte, int, long, double etc.

During coding of an application , situation occurs when we need to use object in place of primitive data types. To implement this Java have wrapper classes for each primitive data type.

All the wrapper classes ( Integer, Long, Byte, Double, Float, Short) are subclasses of the abstract class Number.

The process of writing a primitive data type into an object is called wrapping an Object and it is handled  by compiler. The process is called boxing. Similarly the compiler unboxes the object to a primitive as well. The Number is part of the java.lang package.

Given below the example of boxing and unboxing :

public class boxing{
   public static void main(String args[]){
      Integer a = 3; // boxes int to an Integer object
      a =  a + 30;   // unboxes the Integer to a int
      System.out.println(x); 
   }
}

Output :

Given below table contains the methods for processing numbers :