64     static final class NullComparator<T> implements Comparator<T>, Serializable {

    64     static final class NullComparator<T> implements Comparator<T>, Serializable {

    65         @java.io.Serial

    65         @java.io.Serial

    66         private static final long serialVersionUID = -7569533591570686392L;

    66         private static final long serialVersionUID = -7569533591570686392L;

    67         private final boolean nullFirst;

    67         private final boolean nullFirst;

    68         // if null, non-null Ts are considered equal

    68         // if null, non-null Ts are considered equal

    69         private final Comparator<T> real;

    70         private final Comparator<T> real;

    70 

    71 

    71         @SuppressWarnings("unchecked")

    72         @SuppressWarnings("unchecked")

    72         NullComparator(boolean nullFirst, Comparator<? super T> real) {

    73         NullComparator(boolean nullFirst, Comparator<? super T> real) {

    73             this.nullFirst = nullFirst;

    74             this.nullFirst = nullFirst;