assertNull(announcement);
    public void testDeleteAllAnnouncements() {		IAnnouncement announcement = null;				//read something		Calendar calendar = Calendar.getInstance();		calendar.set(Calendar.YEAR, 2003);		calendar.set(Calendar.MONTH, Calendar.JANUARY);		calendar.set(Calendar.DATE, 21);		calendar.set(Calendar.HOUR_OF_DAY, 0);		calendar.set(Calendar.MINUTE, 0);		calendar.set(Calendar.SECOND, 0);		calendar.set(Calendar.MILLISECOND, 0);				Timestamp date = new Timestamp(calendar.getTime().getTime());				try {			persistentSupport.iniciarTransaccao();			announcement = persistentAnnouncement.readAnnouncementByTitleAndCreationDateAndSite("announcement1deTFCI", date, this.site);			persistentSupport.confirmarTransaccao();		} catch(ExcepcaoPersistencia excepcaoPersistencia) {			fail("testDeleteAllAnnouncements: readAnnouncementByTitleAndDateAndSite");		}		assertNotNull(announcement);		//erase all existing                try {            persistentSupport.iniciarTransaccao();            persistentAnnouncement.deleteAll();            persistentSupport.confirmarTransaccao();        } catch(ExcepcaoPersistencia ex2) {            fail("testDeleteAllAnnouncements: deleteAll");        }		//read something again		announcement = null;		try {			persistentSupport.iniciarTransaccao();			announcement = persistentAnnouncement.readAnnouncementByTitleAndCreationDateAndSite("announcement1deTFCI", date, this.site);			persistentSupport.confirmarTransaccao();		} catch(ExcepcaoPersistencia excepcaoPersistencia) {			fail("testDeleteAllAnnouncements: readAnnouncementByTitleAndDateAndSite");		}		assertNull(announcement);    }