lab3 SysProg

/////////////////////////// Tokens.java
package LispRegexLab;

public enum Tokens {
    Keyword,
    Atom,
    Int,
    Hex,
    Double,
    Comment,
    String,
    Char,
    Directive,
    Operator,
    Punctuation
}
/////////////////////////// Main.java
package LispRegexLab;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.*;
import java.util.regex.*;


public class Main {
    static Map<Tokens , Pattern> regular = new HashMap<Tokens , Pattern>();
    static Map<Tokens , Integer> priority = new HashMap<Tokens , Integer>();

    static void InitRegex(){
        regular.put(Tokens.Atom , Pattern.compile("^(_|[a-z])([a-z]|[0-9]|-)*"));
        regular.put(Tokens.Keyword , Pattern.compile("^(eq|car|cdr|defun|defvar|setq|and|not|or|xor|atom|equal|nil|t|defmacro|cond|if|when|case|loop|do|return|let|list|do|length|setf|format|terpri|dotimes|write-char)"));
        regular.put(Tokens.Int , Pattern.compile("^(0|[1-9]\\d*)"));
        regular.put(Tokens.String, Pattern.compile("^((\"\"([^\\\"\"\\n\\r\\\\]*|\\\\[\\\\0abfnrtuUxv]|\\\\x[\\da-fA-F]{1,4}|\\\\u[\\da-fA-F]{4}|\\\\U[\\da-fA-F]{8})*\"\")|(@\"\"([^\\\"\"]|\"\"\"\")*\"\"))"));
        regular.put(Tokens.Comment, Pattern.compile("^(;+[^\n\r]*)"));
        regular.put(Tokens.Punctuation, Pattern.compile("^[():]"));
        regular.put(Tokens.Hex, Pattern.compile("^0[xX]((0|[1-9a-fA-F][\\da-fA-F]*))"));
        regular.put(Tokens.Operator, Pattern.compile("^\\+ |\\- |\\* |mod |rem |incf |decf |= |> |< |>= |<= |max |min "));
        regular.put(Tokens.Double, Pattern.compile("^(((0|[1-9]\\d*)?\\.\\d+([eE][+-]?\\d+)?[FfDdMm]?)|((0|[1-9]\\d*)([eE][+-]?\\d+)[FfDdMm]?)|((0|[1-9]\\d*)[FfDdMm]))"));
        regular.put(Tokens.Directive, Pattern.compile("^mp:.*"));
        regular.put(Tokens.Char , Pattern.compile("^'[a-z]*"));
    }

    static void InitPriority(){
        priority.put(Tokens.Operator, 1);
        priority.put(Tokens.Punctuation, 2);
        priority.put(Tokens.Double, 3);
        priority.put(Tokens.Int, 4);
        priority.put(Tokens.Hex, 4);
        priority.put(Tokens.Atom, 5);
        priority.put(Tokens.Keyword, 6);
        priority.put(Tokens.String, 7);
        priority.put(Tokens.Char, 7);
        priority.put(Tokens.Directive, 8);
        priority.put(Tokens.Comment, 9);
    }

    static void Tokenize(String text){
        String code = text;
        while(code.length() > 0 && (code.charAt(0) == ' ' || code.charAt(0) == '\n' || code.charAt(0) == '\t'))code = code.substring(1);
        while(code.length() > 0){
            Tokens tokType = Tokens.Comment;
            int len = -1;
            for(Tokens tok : regular.keySet()){
                Pattern trg = regular.get(tok);
                int t = 1 , tmax = 0;
                Matcher tmat = trg.matcher(code.substring(0, t));
                while(t <= code.length()){
                    Matcher m = trg.matcher(code.substring(0, t));
                    if(m.matches() == false){
                        if(t > 20)break;
                        ++t;
                        continue;
                    }
                    tmat = m;
                    tmax = t;
                    ++t;

                    if(t == code.length()){
                        break;
                    }
                }
                if(tmat.matches() == false)continue;
                int tlen = tmax;
                if(tlen > len || (tlen == len && priority.get(tokType) < priority.get(tok))){
                    tokType = tok;
                    len = tlen;
                }
            }
            if(len <= 0){
                System.out.println("Unknown lexeme " + code);
                return;
            }
            System.out.println(code.substring(0 , len) + " " + tokType.toString());
            code = code.substring(len);
            code = code.trim();
        }
    }

    public static void main(String[] args) {
        InitRegex();
        InitPriority();
        File file = new File("input.txt");
        try {
            FileInputStream fis = new FileInputStream(file);
            byte[] data = new byte[(int) file.length()];
            fis.read(data);
            fis.close();
            fis.close();
            String str = new String(data, "UTF-8");
            Tokenize(str);
        }catch(FileNotFoundException e){
            System.out.print("File not found");
        }catch(IOException e) {
            e.printStackTrace();
        }
    }
}