package apifest;

 import junit.framework.TestCase;

 import org.apidesign.apifest08.currency.CurrencyRate;

 import org.apidesign.apifest08.currency.CurrencyRateFactory;

 /** Write a test that works with version from task A and fails with version B.

  */

 public class CurrencyTest extends TestCase {

     public CurrencyTest(String n) {

         super(n);

     }

     public void testCompatibility() throws Exception {

         CurrencyRate rate = CurrencyRateFactory.getInstance().createCurrencyRate("CZK", "USD", 1, 2);

         assertEquals("Implements one interface", 1, rate.getClass().getInterfaces().length);

     }

 }