Mustafa's parse script

Main.java

package main;

import java.io.BufferedWriter;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.StandardOpenOption;
import java.util.Arrays;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Main {
    private static final Pattern usernamePattern = Pattern.compile("Username:\\s+(.+)");
    private static final Pattern passwordPattern = Pattern.compile("Password:\\s+(.+)");
    private static final String splitPattern = "===============";
    private static final Path outputFilePath = Path.of("./output.txt");

    public static void main(String[] args) throws IOException {
        if (args.length < 1) {
            System.out.println("Usage: java -jar <jar-file> <file-to-parse>");
            System.exit(1);
        }
        Path filePath = Path.of(args[0]);
        if (!Files.isReadable(filePath)) {
            throw new IllegalArgumentException("File not found or not readable");
        }
        String fileContent = Files.readString(filePath, StandardCharsets.UTF_8);
        Files.deleteIfExists(outputFilePath);
        BufferedWriter outputFile = Files.newBufferedWriter(outputFilePath, StandardOpenOption.CREATE,StandardOpenOption.APPEND);
        Arrays.stream(fileContent.split(splitPattern))
                .forEach(chunk -> {
                    Matcher usernameMatcher = usernamePattern.matcher(chunk);
                    Matcher passwordMatcher = passwordPattern.matcher(chunk);
                    if (usernameMatcher.find() && passwordMatcher.find()) {
                        String username = usernameMatcher.group(1);
                        String password = passwordMatcher.group(1);
                        try {
                            outputFile.append(username + ":" + password + "\n");
                        } catch (IOException e) {
                            throw new RuntimeException(e);
                        }
                    }
                });

    }
}