public void testPutContainsRetreive() {
SimpleHTTPMessageEntities entities =
new SimpleHTTPMessageEntities();
String headerName = "header";
HeaderImpl header = new HeaderImpl(headerName);
entities.put(header);
assertTrue("The header that was put is not contained in this entities",
entities.containsIdentity(header.getIdentity()));
HTTPMessageEntity retrieved [] =
entities.retrieve(header.getIdentity());
assertEquals("There can be only one", 1, retrieved.length);
assertEquals("The retreived HTTPMessageEntity is not equal to the" +
" entity that was put", header, retrieved[0]);