Get take out Java Intermediate

Hi guys, could you please let me know if this is what step 6 of the take out project means? I am finding difficult to understand exactly the final part, which is in the comments:

//Step 6:
public void addItem(T item) {
//THIS PART: We should add item to shoppingBag and increment the mapping of item or initialize its mapping to 1 if it’s not already a key in shoppingBag.