import org.junit.Test;

import regex.NFA;

import regex.Parser;

import java.util.Scanner;

import java.util.function.Function;

import static org.junit.Assert.assertFalse;

import static org.junit.Assert.assertTrue;

public class RegexTest {

@Test

public void Test() {

Function<String, Boolean> match = createMatch("(a|b)*c");

assertTrue(match.apply("aabbbc"));

assertTrue(match.apply("c"));

assertFalse(match.apply("aabbb"));

match = createMatch(".\\d{3,4}c?");

assertTrue(match.apply("w123"));

assertTrue(match.apply("c0000c"));

assertFalse(match.apply("000c"));

assertFalse(match.apply("a00ac"));

assertFalse(match.apply("b000b"));

}

public static void main(String[] args) {

repl();

}

private static void repl() {

Scanner scanner = new Scanner(System.in);

System.out.println("输入正则表达式:");

Function<String, Boolean> match = createMatch(scanner.nextLine());

while (true) {

System.out.println("输入要匹配的字符串:");

String word = scanner.nextLine();

if (word.equals("exit")) {

System.out.println("bye");

break;

}

System.out.println("匹配结果:" + match.apply(word));

}

}

public static Function<String, Boolean> createMatch(String s) {

var exp = Parser.toPostfix(Parser.insertExplicitConcatOperator(s));

NFA nfa = NFA.toNFA(exp);

return string -> NFA.search(nfa, string);

}

}