driver-core/src/main/com/mongodb/client/model/Filters.java
public static <TItem> Bson in(final String fieldName, final Iterable<TItem> values) {
        return new IterableOperatorFilter<TItem>(fieldName, "$in", values);
    }
public static <TItem> Bson in(final String fieldName, final Iterable<TItem> values) {
        return new IterableOperatorFilter<TItem>(fieldName, "$in", values);
    }
Creates a filter that matches all documents where the value of a field equals any value in the list of specified values.

@param fieldName the field name
@param values    the list of values
@param <TItem>   the value type
@return the filter
@mongodb.driver.manual reference/operator/query/in $in