JavaSE Host名

package com.snail.example;

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

public class HostNameExam {

  public static void main(String[] args) {
    try {
      InetAddress addr = InetAddress.getByName("hondou.homedns.org");
      byte[] ipaddr = addr.getAddress();
      dumpIpAddress(ipaddr);
      
      InetAddress whosAddress = InetAddress.getByAddress(ipaddr);
      System.out.println(whosAddress.getHostName());
    } catch (UnknownHostException e) {
      e.printStackTrace();
    }
  }
  
  public static void dumpIpAddress(byte[] bArray){
    for( byte b : bArray ){
      System.out.print((int)b & 0xff);
      System.out.print(" ");
    }
    System.out.print("\n");
  }
}

package com.snail.example;

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

public class HostNameExam {

  /**
   * @param args
   */
  public static void main(String[] args) {
    try {
      String asciiUrl = IDN.toASCII("日本語.jp");
      System.out.println(asciiUrl);
      InetAddress addr = InetAddress.getByName(asciiUrl);
      byte[] ipaddr = addr.getAddress();
      dumpIpAddress(ipaddr);
      
      InetAddress whosAddress = InetAddress.getByAddress(ipaddr);
      System.out.println(whosAddress.getHostName());
    } catch (UnknownHostException e) {
      e.printStackTrace();
    }
  }
  
  public static void dumpIpAddress(byte[] bArray){
    for( byte b : bArray ){
      System.out.print((int)b & 0xff);
      System.out.print(" ");
    }
    System.out.print("\n");
  }
}