1、遞迴方法。

public class Main {
    
    public static boolean match(char[] str, char[] pattern) {
        return match(str, pattern, 0, 0);
    }

    public static boolean match(char[] str, char[] pattern, int s, int p) {
        if (s == str.length && p == pattern.length) {
            return true;
        }
        if (s < str.length && p >= pattern.length) {
            return false;
        }
        if (p < pattern.length - 1 && pattern[p + 1] == '*') {
            if (s < str.length && (pattern[p] == '.' || str[s] == pattern[p]))
                return match(str, pattern, s, p + 2) ||
                        match(str, pattern, s + 1, p + 2) ||
                        match(str, pattern, s + 1, p);
            else
                return match(str, pattern, s, p + 2);
        }
        if (s < str.length && (pattern[p] == '.' || pattern[p] == str[s]))
            return match(str, pattern, s + 1, p + 1);
        return false;
    }

    public static void main(String[] args) {
        String a = "";
        String b = ".*";
        System.out.println(match(a.toCharArray(), b.toCharArray()));
    }
}