code: private void writeObject(java.io.ObjectOutputStream s)
          throws IOException
      {
          // Write out the threshold, loadfactor, and any hidden stuff
          s.defaultWriteObject();
          
          // Write out number of buckets
          s.writeInt(table.length);
          
          // Write out size (number of Mappings)
          s.writeInt(count);
          
          // Write out keys and values (alternating)
          for (int index = table.length-1; index >= 0; index--) {
              Entry entry = table[index];
              
              while (entry != null) {
                  s.writeInt(entry.key);
                  s.writeObject(entry.value);
                  entry = entry.next;
              }
          }
      }
docs: Save the state of the <tt>IntHashMap</tt> instance to a stream (i.e.,
  serialize it).
  
  @serialData The <i>capacity</i> of the IntHashMap (the length of the
  bucket array) is emitted (int), followed  by the
  <i>size</i> of the IntHashMap (the number of key-value
  mappings), followed by the key (Object) and value (Object)
  for each key-value mapping represented by the IntHashMap
  The key-value mappings are emitted in no particular order.