JAVA public class Q3SimpleStockManager { /**  * A new product has been introduced.  *  * @param sku The products sku  * @param name The products name  * @param price The products price (per unit)  */  public void newItem(String sku, String name, double price) { // FIXME Question 3ia: complete this function  } /**  * Return the name of a product.  *  * @param sku The products sku  * @return the name of the product  */  public String getItemName(String sku) { return null; // FIXME Question 3ib: complete this function  } /**  * Return the price of a product.  *  * @param sku The products sku  * @return the price of the product  */  public double getItemPrice(String sku) { return 0; // FIXME Question 3ic: complete this function  } /**  * Return the amount of stock for a product.  *  * @param sku The products sku  * @return the number of items in stock  */  public int getStock(String sku) { return 0; // FIXME Question 3id: complete this function  } /**  * An product has been sold; reduce current stock accordingly.  *  * @param sku The products sku  * @param sold The quantity sold  * @return The number of items of stock remaining after the sale  */  public int sale(String sku, int sold) { return -1; // FIXME Question 3ie: complete this function  } /**  * New stock has arrived; increase current stock accordingly.  *  * @param sku The products sku  * @param added The quantity newly arrived  */  public void addStock(String sku, int added) { // FIXME Question 3if: complete this function  } /**  * Set the target amount of stock for a product.  *  * @param sku The items sku  * @param target The target quantity desired to be held in stock  */  public void setTargetStock(String sku, int target) { // FIXME Question 3ig: complete this function  } /**  * Stock has been carefully counted. Set current stock correctly.  *  * @param sku The products sku  * @param actual The quantity actually in the store  * @return The stock loss or gain (new current  old current)  */  public int setActualStock(String sku, int actual) { return 0; // FIXME Question 3ih: complete this function  } /**  * Return the number of items required for a given product  * in order to reach the target stock for that item (target - stock)  *  * @param sku The SKU of the item to be queried  * @return The difference between target and actual stock for that item  */  public int getStockRequired(String sku) { return -1; // FIXME Question 3ii: complete this function  } /**  * @return the value of the currently held stock (the price of the  * product multiplied by the number of items in stock, for all items).  */  public double totalStockValue() { return 0; // FIXME Question 3ij: complete this function  } }