Hi, This eg. is from khalid Mughal. int i = -20; final int j = 20; byte b1 = j;//final value of j in range.No cast required byte b2 = i; //Compiler Error. Cast required. If i declare int j without 'final' keyword then compiler will ask for casting otherwise not. Could somebody help me to understand this. Thanks in advance, Salima
A narrowing primitive conversion (like int to byte) may be used if the value of the expression is known at compile time, and is representable in the type of the variable. Declaring it as final effectively makes the value known at compile-time. I think there are also a lot of threads on this topic.
From JLS 5.2: In addition, a narrowing primitive conversion may be used if all of the following conditions are satisfied: * The expression is a constant expression of type byte, short, char or int. * The type of the variable is byte, short, or char. * The value of the expression (which is known at compile time, because it is a constant expression) is representable in the type of the variable.
Joined: Aug 15, 2002
Thanks, Where can i find more on this topic? Reply Salima