Name: saC57035			Date: 01/17/97



The java.awt.Container.remove(int index) throws different exceptions 
if index is out of bounds. The NullPointerException in this case is 
quite unexpected.

Here is the example demonstrating the bug:

---- Test.java ----------------------
import java.awt.*;

public class Test {

public static void main( String argv[] ) {
 Panel p = new Panel();
 for(int i=-2;i<6;i++)
   try {
     p.remove(i);
   } catch(Exception e) {
     System.out.println("Removing "+i+" : "+e); 
   }
}

}
-- The output ----------------
Removing -2 : java.lang.ArrayIndexOutOfBoundsException: -2
Removing -1 : java.lang.ArrayIndexOutOfBoundsException: -1
Removing 0 : java.lang.NullPointerException
Removing 1 : java.lang.NullPointerException
Removing 2 : java.lang.NullPointerException
Removing 3 : java.lang.NullPointerException
Removing 4 : java.lang.ArrayIndexOutOfBoundsException: 4
Removing 5 : java.lang.ArrayIndexOutOfBoundsException: 5
------------------------------

======================================================================



Modifying the above test as follows:

java.awt.*;

public class Test {

    public static void main( String argv[] ) {
         Panel p = new Panel();
         Canvas c;

        for (int i=0;i<100;i++) {
            c = new Canvas();
            p.add(c);
        }

       int[] bad={-20, Integer.MIN_VALUE, Integer.MAX_VALUE, 113};
       for(int i = 0; i < bad.length; i++){
           try {
             p.remove(bad[i]);
           } catch(Exception e) {
             System.out.println("Removing "+ bad[i]+" : "+e);
           }
       }
    }
}

results in the following output <from 

Removing -20 : java.lang.ArrayIndexOutOfBoundsException
Removing -2147483648 : java.lang.ArrayIndexOutOfBoundsException
Removing 2147483647 : java.lang.ArrayIndexOutOfBoundsException
Removing 113 : java.lang.NullPointerException

Should the removal of the element at position 113 of the container array not result in an ArrayIndexOutOfBoundsException as this position is out of bounds of the array?

###@###.### 2001-10-17