for (Planet planet : Planet.values()) {
TableRow row = new TableRow();
for (ColumnDescription selectionColumn : requiredColumns) {
String columnName = selectionColumn.getId();
if (columnName.equals(PLANET_COLUMN)) {
row.addCell(planet.name());
} else if (columnName.equals(MASS_COLUMN)) {
row.addCell(planet.getMass());
} else if (columnName.equals(GRAVITY_COLUMN)) {
row.addCell(planet.getSurfaceGravity());
} else if (columnName.equals(MOONS_COLUMN)) {