Help in Final variables

[Mani Venkata Kanth]

class a{
static byte m1() {
final char c = '\u0001';
return c; // 1
}
static byte m3(final char c) {return c;} // 2
public static void main(String[] args) {
char c = '\u0003';
System.out.print(""+m1()+m3(c));
}}

Explain output.... output is Compile time error at 2

[Barry Gaunt]

What is the compile error? What does it mean to you?

[Gowher Naik]

class a{
static byte m1() {
final char c = '\u0001'; //line 3
return c; //line 4
}
static byte m3(final char c) { //line 6
return c;//line 7
} 
public static void main(String[] args) {
char c = '\u0003';
System.out.print(""+m1()+m3(c));//line 11
}
}

In method m1 final char c at line 3 is compile time constant
so c is within range of byte so there is no problem while
returning c at line 4

At line 7 you are returning char from method m3
But method m3 return byte.
Keep in mind final char c at line 6 which you are returning
at line 7 is constant "but not compile time constant".
This is why there is "possible loss of precision"
error at line 7.

[Mani Venkata Kanth]

---------- Java Compiler ----------
a.java:6: possible loss of precision
found : char
required: byte
static byte m3(final char c) {return c;} // 2
^
1 error

Output completed (2 sec consumed) - Normal Termination
------------------------------------------------------------
why doesnt the error occur at //1 ???

[Mani Venkata Kanth]

Thanks... gowher amin naik .. for clearing my doubt..