public static Bson regex(final String fieldName, final Pattern pattern) {
        notNull("pattern", pattern);
        return new SimpleEncodingFilter<Pattern>(fieldName, pattern);
    }
public static Bson regex(final String fieldName, final Pattern pattern) {
        notNull("pattern", pattern);
        return new SimpleEncodingFilter<Pattern>(fieldName, pattern);
    }
public static Bson regex ( final String fieldName , final Pattern pattern ) { notNull ( "pattern" , pattern ) ; return new SimpleEncodingFilter < Pattern > ( fieldName , pattern ) ; }
Creates a filter that matches all documents where the value of the field matches the given regular expression pattern with the given
options applied.

@param fieldName the field name
@param pattern   the pattern
@return the filter
@mongodb.driver.manual reference/operator/query/regex $regex
Creates a filter that matches all documents where the value of the field matches the given regular expression pattern with the given options applied .