So, I understand that null is not a value and just means the target doesn't exist, but I need to use something like it to reference empty elements of an array.  I need to do something like this:

for(int i=0; i < array1.length; i++){
 if(array1[i] != null){
   if(array2[i] == something){
     array1[i] = null;
   }
 }
}

In other words, I need to check if elements of the array are undefined as well as delete elements.  Setting them equal to 0 won't work for my purposes.  Any ideas?

Thanks,
Zach