import java.io.BufferedReader;

import java.io.FileReader;

import java.io.IOException;

import java.util.HashMap;

import java.util.Map;

public class HeaderValidator {

public static void main(String[] args) {

if (args.length != 1) {

System.out.println("Usage: java HeaderValidator <header_file>");

return;

}

String headerFilePath = args[0];

validateHeaders(headerFilePath);

}

public static void validateHeaders(String headerFilePath) {

try (BufferedReader reader = new BufferedReader(new FileReader(headerFilePath))) {

String line;

Map<String, String> headers = new HashMap<>();

while ((line = reader.readLine()) != null) {

// Basic validation: check for "key: value" format

if (line.contains(":")) {

String[] parts = line.split(":", 2); // Split only at the first colon

if (parts.length == 2) {

String key = parts[0].trim();

String value = parts[1].trim();

// Simple validation: check for empty key or value

if (key.isEmpty() || value.isEmpty()) {

System.err.println("Invalid header format: " + line + " - Key or value cannot be empty.");

return;

}

headers.put(key, value);

} else {

System.err.println("Invalid header format: " + line);

return;

}

} else {

System.err.println("Invalid header format: " + line);

return;

}

}

// Print the validated headers

System.out.println("Valid Headers:");

for (Map.Entry<String, String> entry : headers.entrySet()) {

System.out.println(entry.getKey() + ": " + entry.getValue());

}

} catch (IOException e) {

System.err.println("Error reading header file: " + e.getMessage());

}

}

}