Integer to byte casting in Java

Question

In Java we can do

byte b = 5;    

But why can\'t we pass same argument to a function which accepts byte

myObj         


        

Answer 1

The reason is that when you are narrowing a primitive, you must explicitly make a cast - so you acknowledge a possible loss of data.

To illustrate, when casting 5 there is no loss because the value is within the -128...127 byte value range, but consider a larger int value, say 300 - if you cast to byte, you must throw away some bits to make it fit into 8 bits.

The topic is covered in full here.