package p; import java.util.Enumeration; import java.util.Vector; public class A { private void createTestList(TestCollector collector) { Enumeration each= collector.collectTests(); while (each.hasMoreElements()) { String s= (String) each.nextElement(); } } } interface TestCollector { public Enumeration collectTests(); } class Collector implements TestCollector { public Enumeration collectTests() { Vector v= new Vector(); v.add("Test1"); return v.elements(); } }