assertEquals("unexpected cell contents (first visible row expected)",
"188", treeTable.getCell(189, 0).getText());
assertEquals("unexpected cell contents (first cached row expected)",
"158", treeTable.getCell(159, 0).getText());
assertEquals("elements found where there should be none", 0, treeTable
.findElements(By.vaadin("#row[158]/col[0]")).size());
assertEquals("elements found where there should be none", 0, treeTable
.findElements(By.vaadin("#row[204]/col[0]")).size());
// check the actual visibility