if (operation == null) {
} else if (operation.equals("add")) {
FilterRow filterRow = compositeFilter.addFilterRow();
filterRow.encodeRow(context, compositeFilter);
} else if (operation.equals("clear")) {
compositeFilter.clear();
encodeNoFilterRow(context, compositeFilter);
} else if (operation.equals("remove")) {
int index = (Integer) jsonParam.get("index");
compositeFilter.removeFilterRow(index);
if (compositeFilter.isEmpty()) {