code: public boolean extractInto(ItemStack itemStack)
  	{
  		ItemStacksMerger ism = new ItemStacksMerger(getItemStack(), itemStack);
  		if (!ism.merge())
  			return false;
  		if (ism.nbMerged != 0)
  		{
  			setItemStack(ism.merge);
  			onSlotChanged();
  		}
  		return itemStack.getCount() >= itemStack.getMaxStackSize();
  	}
docs: Extracts the maximum possible from this slots {@link ItemStack} into <code>itemStack</code>.<br>
  
  @param itemStack the itemStack the slot is extracted into
  @return true, if the destination itemStack is now full