How do I convert raw IP address to String?

This example show you how to convert a raw IP address, an array of byte, returned by InetAddress.getAddress() method call to its string representation.

package org.kodejava.net;

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

public class RawIPToString {
    public static void main(String[] args) {
        byte[] ip = new byte[0];
        try {
            InetAddress address = InetAddress.getLocalHost();
            ip = address.getAddress();
        } catch (UnknownHostException e) {
            e.printStackTrace();
        }
        String ipAddress = RawIPToString.getIpAddress(ip);
        System.out.println("IP Address = " + ipAddress);

        try {
            InetAddress address = InetAddress.getByName("google.com");
            ip = address.getAddress();
        } catch (UnknownHostException e) {
            e.printStackTrace();
        }
        ipAddress = RawIPToString.getIpAddress(ip);
        System.out.println("IP Address = " + ipAddress);
    }

    /**
     * Convert raw IP address to string.
     *
     * @param rawBytes raw IP address.
     * @return a string representation of the raw ip address.
     */
    private static String getIpAddress(byte[] rawBytes) {
        int i = 4;
        StringBuilder ipAddress = new StringBuilder();
        for (byte raw : rawBytes) {
            ipAddress.append(raw & 0xFF);
            if (--i > 0) {
                ipAddress.append(".");
            }
        }
        return ipAddress.toString();
    }
}

This example will print something like:

IP Address = 30.30.30.60
IP Address = 142.251.10.113

How do I get a localhost hostname?

package org.kodejava.network;

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

public class HostNameExample {
    public static void main(String[] args) {
        try {
            InetAddress address = InetAddress.getLocalHost();

            System.out.println("Hostname: " + address.getHostName());
        } catch (UnknownHostException e) {
            e.printStackTrace();
        }
    }
}

An example of output produce by the code snippet above is:

Hostname: Krakatau