import java.util.Arrays;

public class ConfigValidator {

public static void validateConfig(String[] args) {

// Validate the number of arguments

if (args == null || args.length < 2) {

System.err.println("Error: Incorrect number of arguments. Usage: <program> <input_file> <option1> <value1>");

System.exit(1); // Exit with an error code

}

String inputFile = args[1]; // Get the input file name

String option1 = args[2]; // Get the first option

String value1 = args[3]; // Get the value for the first option

// Validate the input file exists

if (!new java.io.File(inputFile).exists()) {

System.err.println("Error: Input file '" + inputFile + "' does not exist.");

System.exit(1);

}

// Validate option 1

if (!option1.equals("flag1") && !option1.equals("flag2")) {

System.err.println("Error: Invalid option. Must be 'flag1' or 'flag2'.");

System.exit(1);

}

// Validate value 1 - example: check if it's a number

try {

Double.parseDouble(value1); // Attempt to parse as a double

} catch (NumberFormatException e) {

System.err.println("Error: Value for option '" + option1 + "' must be a number.");

System.exit(1);

}

// Example of validating a range

if (option1.equals("flag2")) {

int value2 = Integer.parseInt(value1); // Get the value

if (value2 < 0 || value2 > 100) {

System.err.println("Error: Value for option 'flag2' must be between 0 and 100.");

System.exit(1);

}

}

// If all validations pass, the configuration is valid

System.out.println("Configuration is valid.");

}

public static void main(String[] args) {

//Example usage for testing

String[] validArgs = {"myprogram", "input.txt", "flag1", "123"};

String[] invalidArgs1 = {"myprogram", "input.txt", "invalid_flag", "abc"};

String[] invalidArgs2 = {"myprogram", "nonexistent.txt", "flag1", "123"};

validateConfig(validArgs);

//validateConfig(invalidArgs1);

//validateConfig(invalidArgs2);

}

}