How to validate an IP address in Java?

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import java.net.InetAddress;
import java.net.UnknownHostException;

public class Main {
    public static void main(String[] args) throws UnknownHostException {
        // IP address to validate
        String ip = "192.168.0.1";

        // Use the InetAddress#getByName method to check if the IP address is valid
        InetAddress address = InetAddress.getByName(ip);

        // Check if the address is an instance of InetAddress
        if (address != null) {
            System.out.println("Valid IP address");
        } else {
            System.out.println("Invalid IP address");
        }
        // Output: Valid IP address
    }
}

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import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Main {
    public static void main(String[] args) {
        // IP address to validate
        String ip = "192.168.0.1";

        // Regular expression pattern for IP address validation
        String pattern = "^([01]?\d\d?|2[0-4]\d|25[0-5])\." +
                        "([01]?\d\d?|2[0-4]\d|25[0-5])\." +
                        "([01]?\d\d?|2[0-4]\d|25[0-5])\." +
                        "([01]?\d\d?|2[0-4]\d|25[0-5])$";

        // Create a Pattern object with the regex pattern
        Pattern p = Pattern.compile(pattern);

        // Create a Matcher object to match the pattern against the IP address
        Matcher m = p.matcher(ip);

        // Check if the IP address matches the regex pattern
        if (m.matches()) {
            System.out.println("Valid IP address");
        } else {
            System.out.println("Invalid IP address");
        }
        // Output: Valid IP address
    }
}