Resolves ip address and returns host name as a string
// Copyright (c) 2003-2009, Jodd Team (jodd.org). All Rights Reserved.
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.Inet4Address;
import java.net.InetAddress;
import java.net.URL;
import java.net.UnknownHostException;
/**
* Network utilities.
*/
public class NetUtil {
/**
* Resolves hostname and returns ip address as a string.
*/
public static String resolveHost(String hostname) {
try {
InetAddress addr = Inet4Address.getByName(hostname);
byte[] ipAddr = addr.getAddress();
StringBuilder ipAddrStr = new StringBuilder(15);
for (int i = 0; i < ipAddr.length; i++) {
if (i > 0) {
ipAddrStr.append('.');
}
ipAddrStr.append(ipAddr[i] & 0xFF);
}
return ipAddrStr.toString();
} catch (UnknownHostException uhex) {
return null;
}
}
/**
* Resolves string ip address and returns host name as a string.
*/
public static String resolveIp(String ip) {
try {
InetAddress addr = InetAddress.getByName(ip);
return addr.getHostName();
} catch (UnknownHostException uhex) {
return null;
}
}
/**
* Resolves ip address and returns host name as a string.
*/
public static String resolveIp(byte[] ip) {
try {
InetAddress addr = InetAddress.getByAddress(ip);
return addr.getHostName();
} catch (UnknownHostException uhex) {
return null;
}
}
}
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