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General Java Questions II
recurseList( l );
Without any problem.
by Davide Bianchi
Q: I got a problem with an array/vector...
I got a problem with an array/vector.
my class contains a member:
static Vector quad[][];
....
in my constructor I got:
Vector quad[][] = new Vector[row][col];
for (int i = 0; i < row; i++){
for (int j = 0; j < col; j++){
quad[i][j] = new Vector (0,1);
}
}
// row and col are int between (10..50) -- it's a big I know, but that
might not be the problem
My PROBLEM (and I don't know what to do, really), I can't access quad[x][y] outside
of the constructor!!!! Within the constructor I've got full access on quad[x][x]. Java
(1.2) returns a NullPointerException on any method except within the constructor!!!
What's my fault!???
Answer: I guess you shouldn't write Vector here:
Vector quad[][] = new Vector[row][col];
so, the correct variant may be:
quad[][] = new Vector[row][col];
I guess You just overridden your static variable with one defined in your constructor:
Vector quad[][].
Thus, you're initializing NOT your class-scope static variable but your
constructor-scope quad. It's not reachable outside the constructor. And as for static
quad, it has never been initialized! And a first reference to it causes
NullPointerException. I guess. I hope I'm right :)
--
Xao Rom
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