For... Each loop problem using hash map

[musiclover92]

I am currently doing an estate agency java project. I have properties and buyers both stored in two different Hash Maps. In the following method I am trying to display the number of sold houses (there is a buyer).

I keep getting an error message saying: for each not applicable to expression type.

Here is my code:

/**
* Displays the number of houses that are sold.
*/
public void displaySoldHouses()
{
int count = 0;
for (Property property : properties) {
if (property instanceof House && property.isSold()) {
count = count + 1;
}
}
System.out.println("You own " + count + " houses");
}

OR because it's a hash map do I need to create a set like in this alternative method:

/**
* Displays the total number of houses which have been sold.
*/
public void displayHousesSold()
{
int count = 0;
if (!properties.isEmpty()) {
Set <String> keys = properties.keySet();
for (String id : keys) {
if (properties.get(id).isSold()) {
count = count + 1;
}
else {
System.out.println("There are no houses sold");
}
}
System.out.println("The number of sold houses are: " + count);
}
else {
System.out.println("There are no properties in the HashMap!");
}
}

I have tried the method above, it compiles perfectly but I don't know how to access just the House objects in the hash map as the hash map contains apartments too and I just need the house ones for this method. It just returns the number of properties sold overall but i only need to show the amount of sold houses.

Any help is appreciated.

[Junky]

The for each loop only works with classes that implement the Iterable interface. I believe HashMap doesn't. However you can get a Set from the Map which does implement Iterable.

[musiclover92]

Yeah that's what I was thinking thank you. So the second method I provided would be more correct then. But how do I only access the properties that are houses?

[Junky]

If House is a subclass of Property then you can use the instanceof operator.

[musiclover92]

Can I use the instanceof operator in the second method I did? Because it doesn't work in the first one, i keep getting an error.