@Test
public void testMissingValues() throws Exception {

	assertEquals("<div>-missing value-</div>-missing value-", helper.replace("<div>{{key2}}</div>{{key3}}", null));
	assertEquals("<div>-missing value-</div>-missing value-", helper.replace("<div>{{key2}}</div>{{key3}}", ""));
	assertEquals("<div>/ui/img/image_preview.png</div>-missing value-",
			helper.replace("<div>{{key1}}</div>{{key3}}", null));
}