@SuppressWarnings("unchecked")
    public static <L, M, R, S> Quartet<L, M, R, S>[] emptyArray() {
        return (QuarterAdapter<L, M, R, S>[]) EMPTY_ARRAY;
    }
Returns the empty array singleton that can be assigned without compiler warning.

@param <L> the f1 element type
@param <M> the f2 element type
@param <R> the f3 element type
@param <S> the f4 element type
@return the empty array singleton that can be assigned without compiler warning.
inlong-manager/manager-common/src/main/java/org/apache/inlong/manager/common/tool/excel/tuple/Quartet.java