public class TestDefAssign {
public static char UNSET;
public static void main(String[] args) {
char c;
char d = 0;
//System.out.println(d == c);
//System.out.println(d != c);
//System.out.println(c);
System.out.println(d != UNSET);
System.out.println(d == UNSET);
//System.out.println(c != UNSET);
//System.out.println(c == UNSET);
}
}
Uncomment any of the commented out lines and you get something like
TestDefAssign.java:12: variable c might not have been initialized
The output of the program is
false
true
Which indicates that UNSET actually has the value of 0, but I don't think
you're supposed to use it.
On Friday 27 September 2002 06:36 pm, Henri Yandell wrote:
> Weird. I'd thought all values in Java were set to a defined value. Thought
> we got rid of the unassigned stuff with C. But I don't delve into the JVM
> and language spec enough so could be wrong very easily.
>
> Hen
>
> On 27 Sep 2002, Steve Downey wrote:
> > CharRange uses an unassigned static character, UNSET, as a flag value
> > for testing if the range is a range or a single value.
> >
> > This looks a little odd to me. I had the distinct impression that
> > accessing an unassigned value was an error. However, the comparison
> > works. I'm just not sure it's working as intended, and won't fail to
> > work an a different VM?
> >
> > relevant code:
> > /**
> > * Used internally to represent null in a char.
> > */
> > private static char UNSET;
> >
> > // ...
> >
> > /**
> > * Is this CharRange over many characters
> > *
> > * @return boolean true is many characters
> > */
> > public boolean isRange() {
> > return this.close != UNSET;
> > }
> >
> >
> >
> >
> >
> >
> > --
> > To unsubscribe, e-mail:
> > <mailto:[EMAIL PROTECTED]> For additional
> > commands, e-mail: <mailto:[EMAIL PROTECTED]>
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