After knowing primitive data types and Java rules of Data Type Casting (Type Conversion), let us cast short to byte as an example.
The byte takes 1 byte of memory and short takes 2 bytes of memory. Assigning 2 bytes of memory to 1 byte of memory requires explicit casting. This is known as narrowing conversion.
See the order of data types to know the rules of casting.
byte –> short –> int –> long –> float –> double
The left-side value can be assigned to any right-side value and is done implicitly. The reverse like short to byte requires explicit casting.
Examples of implicit casting
short x = 10;
int y = x;byte x = 10;
short y = x;
Following program explains explicit casting, Java style where a short is assigned to byte.
public class Conversions
{
public static void main(String args[])
{
short s1 = 10;
// byte b1 = s1;
byte b1 = (byte) s1; // observe syntax of Java explicit casting
System.out.println("short value: " + b1); // prints 10
System.out.println("Converted byte value: " + b1); // prints 10
}
}
Output screenshot of short to byte Java
byte b1 = s1;
The above statement raises a compilation error "possible loss of precision".
byte b1 = (byte) s1;
The short s1 is explicitly type casted to byte b1. Observe, the syntax of explicit casting. On both sides, it should be byte.