Task: Just in time processing on a character stream



C#: using System;
using System.Collections.Generic;
using System.Linq;

namespace JustInTimeProcessing {
    struct UserInput {
        public UserInput(string ff, string lf, string tb, string sp) {
            FormFeed = (char)int.Parse(ff);
            LineFeed = (char)int.Parse(lf);
            Tab = (char)int.Parse(tb);
            Space = (char)int.Parse(sp);
        }

        public char FormFeed { get; }
        public char LineFeed { get; }
        public char Tab { get; }
        public char Space { get; }
    }

    class Program {
        static List<UserInput> GetUserInput() {
            string h = "0 18 0 0 0 68 0 1 0 100 0 32 0 114 0 45 0 38 0 26 0 16 0 21 0 17 0 59 0 11 "
                + "0 29 0 102 0 0 0 10 0 50 0 39 0 42 0 33 0 50 0 46 0 54 0 76 0 47 0 84 2 28";
            return h.Split(' ')
                .Select((x, idx) => new { x, idx })
                .GroupBy(x => x.idx / 4)
                
                .Select(g => {
                    var ge = g.Select(a => a.x).ToArray();
                    return new UserInput(ge[0], ge[1], ge[2], ge[3]);
                })
                .ToList();
        }

        static void Decode(string filename, List<UserInput> uiList) {
            string text = System.IO.File.ReadAllText(filename);

            bool Decode2(UserInput ui) {
                char f = (char)0;
                char l = (char)0;
                char t = (char)0;
                char s = (char)0;

                foreach (char c in text) {
                    if (f == ui.FormFeed && l == ui.LineFeed && t == ui.Tab && s == ui.Space) {
                        if (c == '!') return false;
                        Console.Write(c);
                        return true;
                    }
                    if (c == '\u000c') {
                        f++; l = (char)0; t = (char)0; s = (char)0;
                    } else if (c == '\n') {
                        l++; t = (char)0; s = (char)0;
                    } else if (c == '\t') {
                        t++; s = (char)0;
                    } else {
                        s++;
                    }
                }

                return false;
            }

            foreach (UserInput ui in uiList) {
                if (!Decode2(ui)) {
                    break;
                }
            }
            Console.WriteLine();
        }

        static void Main(string[] args) {
            var uiList = GetUserInput();
            Decode("theraven.txt", uiList);

            Console.ReadLine();
        }
    }
}



Java: import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;
import java.util.function.Predicate;

public class Processing {
    private static class UserInput {
        private char formFeed;
        private char lineFeed;
        private char tab;
        private char space;

        private UserInput(char formFeed, char lineFeed, char tab, char space) {
            this.formFeed = formFeed;
            this.lineFeed = lineFeed;
            this.tab = tab;
            this.space = space;
        }

        char getFormFeed() {
            return formFeed;
        }

        char getLineFeed() {
            return lineFeed;
        }

        char getTab() {
            return tab;
        }

        char getSpace() {
            return space;
        }
    }

    private static List<UserInput> getUserInput() {
        String h = "0 18 0 0 0 68 0 1 0 100 0 32 0 114 0 45 0 38 0 26 0 16 0 21 0 17 0 59 0 11 " +
            "0 29 0 102 0 0 0 10 0 50 0 39 0 42 0 33 0 50 0 46 0 54 0 76 0 47 0 84 2 28";
        String[] s = h.split(" ");

        List<UserInput> uiList = new ArrayList<>();
        for (int idx = 0; idx + 3 < s.length; idx += 4) {
            char c0 = (char) Integer.parseInt(s[idx + 0]);
            char c1 = (char) Integer.parseInt(s[idx + 1]);
            char c2 = (char) Integer.parseInt(s[idx + 2]);
            char c3 = (char) Integer.parseInt(s[idx + 3]);

            UserInput userInput = new UserInput(c0, c1, c2, c3);
            uiList.add(userInput);
        }
        return uiList;
    }

    private static void decode(String fileName, List<UserInput> uiList) throws IOException {
        Path path = Paths.get(fileName);
        byte[] bytes = Files.readAllBytes(path);
        String text = new String(bytes, StandardCharsets.UTF_8);

        Predicate<UserInput> decode2 = (UserInput ui) -> {
            char f = 0;
            char l = 0;
            char t = 0;
            char s = 0;
            char ff = ui.getFormFeed();
            char lf = ui.getLineFeed();
            char tb = ui.getTab();
            char sp = ui.getSpace();

            for (char c : text.toCharArray()) {
                if (f == ff && l == lf && t == tb && s == sp) {
                    if (c == '!') {
                        return false;
                    }
                    System.out.print(c);
                    return true;
                }
                switch (c) {
                    case '\u000c':
                        f++;
                        l = 0;
                        t = 0;
                        s = 0;
                        break;
                    case '\n':
                        l++;
                        t = 0;
                        s = 0;
                        break;
                    case '\t':
                        t++;
                        s = 0;
                        break;
                    default:
                        s++;
                        break;
                }
            }

            return false;
        };

        for (UserInput ui : uiList) {
            if (!decode2.test(ui)) {
                break;
            }
        }
        System.out.println();
    }

    public static void main(String[] args) throws IOException {
        List<UserInput> uiList = getUserInput();
        decode("theRaven.txt", uiList);
    }
}