why no error with byte b=3+5

[Arun Maalik]

Dear sir i would like to know one thing as see the following code


1 byte a=5;
2 byte b=6;
3 byte c=a+b;

in the above code. It is flaging an error mesage that "possible loss of precission" well no problem becaus we know that result of any expression is int that's why this error , but here one question like see

byte b=23;

Here 23 will automaticaly get casted but why in the line c=a+b compiler is not casting automaticaly why?

one thing more sir if i am coding like this as see

byte b=3+5; Here it is not genrating any error message why although 3+5 is also an expression.

Regard

Arun kumar maalik

[Keith Lynn]

Originally posted by Arun Maalik:
Dear sir i would like to know one thing as see the following code


1 byte a=5;
2 byte b=6;
3 byte c=a+b;

in the above code. It is flaging an error mesage that "possible loss of precission" well no problem becaus we know that result of any expression is int that's why this error , but here one question like see

byte b=23;

Here 23 will automaticaly get casted but why in the line c=a+b compiler is not casting automaticaly why?

one thing more sir if i am coding like this as see

byte b=3+5; Here it is not genrating any error message why although 3+5 is also an expression.

Regard

Arun kumar maalik

The difference is that 3+5 can be computed at compile-time because they are compile-time constants.

However, in the first code, a and b are not compile-time constants, and at compile-time, the type of a+b is int and can't be assigned to a byte without a cast.

[catherine powell]

there's an EXCELLENT article called "The SCJP Tip Line Implicit Conversions, Explicitly" by Corey McGlone about this topic that helped me a lot.
[ November 17, 2006: Message edited by: catherine powell ]

[Amresh Singh]

To add on to this the following code will compile because a and b are compile time constants
final int a = 1;
final int b = 2;
int c = a + b;

However, this code will not compile because a nd b are runtime constants(not compile time constants)

final int a;
final int b;
a = 1;
b = 2;
int c = a + b;