TDD For Professionals - Mocks

Invoice.java

package module2.exercise.mocks;

import java.util.Calendar;

public class Invoice {

	private Calendar date;
	private String customer;
	private double amount;
	public Invoice(Calendar date, String customer, double amount) {
		this.date = date;
		this.customer = customer;
		this.amount = amount;
	}
	public Calendar getDate() {
		return date;
	}
	public String getCustomer() {
		return customer;
	}
	public double getAmount() {
		return amount;
	}
	
	
}

InvoiceFilter.java

package module2.exercise.mocks;

import java.util.ArrayList;
import java.util.Calendar;
import java.util.List;

public class InvoiceFilter {

	private final InvoiceRepository invoices;

	public InvoiceFilter(InvoiceRepository invoiced) {
		this.invoices = invoiced;
	}
	
	public List<Invoice> filter() {
		
		List<Invoice> filtered = new ArrayList<Invoice>();
		
		for(Invoice invoice : invoices.all()) {
			if (invoice.getAmount() > 2000) filtered.add(invoice);
			else if (invoice.getAmount() < 2000 && invoice.getCustomer().equals("MICROSOFT")) filtered.add(invoice);
			else if (invoice.getDate().get(Calendar.YEAR) < 1999) filtered.add(invoice);
		}
		
		return filtered;
	}
}

InvoiceRepository.java

package module2.exercise.mocks;

import java.util.List;

public interface InvoiceRepository {
	List<Invoice> all();
}

Thank you for the code for better explanation..