NullPointerException question (probably easy)

Question

Hi,
I am currently using a JDK 1.2 release from 1999 or so.
In a class, I have an array:
class foo {
double bar[];
In a method, I populate the array:
void foobar ()
bar = new double[13];
bar[0] = 0.0;
... // all 13 elements assigned values
Nothing else touches the array.
I instantiate the class as "g" and call g.foobar()
As soon as it returns, g.bar is null. Referencing it gives NullPointerException.
help?
the bug database comes back with too many hits to look through for NullPointerException. I've encountered this bug before, usually able to work around it, not this time. The class implements a bunch of gradients for a nonlinear programming (NLP) problem. I can send anyone who is interested the source.
I probably just need a patch. Can someone point me toward one?

Answer 1

import java.io.*;
import java.util.*;
class find2 {
     double bar[];
     void foobar(){
          bar = new double[13];
          for(int i=0;i<13;i++){
               bar[i] = i*1.1;
     public static void main (String args[]){
          find2 g = new find2();
          g.foobar();//comment this line and see
          for(int j=0;j<g.bar.length;j++){
               System.out.println(g.bar[j]);
          for(int j=0;j<g.bar.length;j++){
               System.out.println(g.bar[j]);
}i just tried this little program, i just initialized as you have done in the foobar() method, U can see, if in the main program, if you comment out the line g.foobar(); then it throws a nullpointerException, otherwise it will not, so, i guess you are not calling the method before trying to access the bar values