获取IP地址

参考CORE JAVA。

在JAVA中，InetAddress类用于操作与IP地址相关的内容，常用方法如下：

java.net.InetAddress 1.0
• static InetAddress getByName(String host)
• static InetAddress[] getAllByName(String host)
constructs an InetAddress, or an array of all Internetaddresses, for the given host name.
• static InetAddress getLocalHost()
constructs an InetAddress for the local host.
• byte[] getAddress()
returns an array of bytes that contains thenumerical address.
• String getHostAddress()
returns a string with decimal numbers,separated by periods, for example "132.163.4.102".
• String getHostName()
returns the host name.

package com.lujinhong.corejava;

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

public class InetAddressTest {

    public static void main(String[] args) {

        try {
			// Get the first argument as the hostname.
            if (args.length > 0) {
                InetAddress[] inetAddresses = InetAddress.getAllByName(args[0]);
                for(InetAddress ia : inetAddresses){
                    System.out.println(ia);
                }
            }else{
			//if No argument, get the localhost ip address.
                InetAddress localHostAddress = InetAddress.getLocalHost();
                System.out.println(localHostAddress);
                System.out.println(localHostAddress);
            }
        } catch (UnknownHostException e) {
            e.printStackTrace();
        }
    }
}