how do I complete this

Question

import java.util.*;

/**
* The parts offered.
* TODO: Complete the getCost method in this class for part 3.
*/
public class PartsInventory
{
// The parts, indexed by part code.
private final Map<Integer, Part> parts = new TreeMap<>();

/**
* TODO Part 3.
* Calculate the cost of the given order.
* @param order The order.
* @return The cost of the order.
*/
public double getCost(ClientOrder order)
{
double cost = 0;
// TODO: Calculate the cost of each item in the customer's order.

return cost;
}

/**
* Get the parts in the inventory.
* @return The parts.
*/
public Collection<Part> getParts()
{
return parts.values();
}

/**
* Add a part to the inventory.
* @param aPart The part to be added.
*/
public void addPart(Part aPart)
{
parts.put(aPart.partCode(), aPart);
}

/**
* Print the parts.
*/
public void printParts() {
for (Part aPart : parts.values()) {
System.out.println(aPart);
}
}
}

Answer 1

I'm pretty sure you need to iterate through the order and match the parts to their prices, adding each price to your cost.