有没有什么命令行函数可以从一个巨大的Java文件中返回主类的名称？

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class MainClassFinder {
    public static void main(String[] args) {
        String filename = "your_huge_java_file.java";
        String mainClassName = findMainClass(filename);
        System.out.println("Main class name: " + mainClassName);
    }

    public static String findMainClass(String filename) {
        String mainClassName = null;
        try {
            BufferedReader reader = new BufferedReader(new FileReader(filename));
            String line;
            while ((line = reader.readLine()) != null) {
                Pattern pattern = Pattern.compile("public\\s+class\\s+(\\w+)\\s*\\{");
                Matcher matcher = pattern.matcher(line);
                if (matcher.find()) {
                    mainClassName = matcher.group(1);
                    break;
                }
            }
            reader.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return mainClassName;
    }
}