题解 | #参数解析#

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
import java.util.stream.Collectors;

public class Main {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);

        while (in.hasNextLine()) {

            String commandString = in.nextLine();
            char[] chars = commandString.toCharArray();
            int length = chars.length;

            boolean leftQuote = false;
            int previousSpaceIndex = -1;

            List<String> params = new ArrayList<>();

            for (int i = 0; i < length; i++) {
                char c = chars[i];
                if (c == ' ' && !leftQuote) {
                    params.add(commandString.substring(previousSpaceIndex + 1, i));
                    previousSpaceIndex = i;
                }
                if (c == '"') {
                    if (!leftQuote) {
                        leftQuote = true;
                    } else {
                        leftQuote = false;
                    }
                }
                if (i == length - 1) {
                    params.add(commandString.substring(previousSpaceIndex + 1, length));
                }

            }

            params = params.stream().map(param -> {
                if (param.startsWith("\"") && param.endsWith("\"")) {
                    return param.substring(1, param.length() - 1);
                }
                return param;
            }).collect(Collectors.toList());

            System.out.println(params.size());
            params.forEach(System.out::println);

        }

        in.close();
    }

}