### Question:
SqlMapClientDaoAdapter implements MappingDao<Object>, Locator { public Object update(String id, Object entity) { try { sqlMapClient.update(id, entity); } catch (SQLException e) { throw new DaoException("Exception throw while executing update with statement id '" + id + "' and entity '" + entity + "'", e); } return null; } SqlMapClientDaoAdapter(SqlMapClient sqlMapClient); Object update(String id, Object entity); Object insert(String id, Object entity); Object delete(String id, Object entity); @SuppressWarnings("unchecked") Collection<Object> lookup(String id, Map<String, ?> parameters); @SuppressWarnings("unchecked") Collection<Object> lookup(String id, Object ... parameters); SqlMapClient getSqlMapClient();  }### Answer:
@Test(groups = "unit") public void test_merge() throws SQLException { Object toMerge = new Object(); Object merged = adapter.update("id", toMerge); verify(sqlMapClient).update(eq("id"), same(toMerge)); assertNull(merged); }