Learning-Java/Java Sets/src/ProductCatalogue.java

import common.Product;
import common.Supplier;

import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;

public class ProductCatalogue implements Iterable<Product> {
    private final Set<Product> products = new HashSet<>();

    public void addSupplier(final Supplier supplier) {

        products.addAll(supplier.getProducts());
    }

    @Override
    public Iterator<Product> iterator() {
        return products.iterator();
    }
}