ip2long

package com.juanpi.order.common;

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

/**
 * @author [e-mail]
 *
 */
public class Ip2Number {

	/**
	 * @param ip
	 * @return 有符号的整形数；当ip>128.0.0.0时为负数；
	 * @throws UnknownHostException
	 * @author wenc
	 */
	public static int ip2Int(String ip) throws Exception {
		InetAddress address = InetAddress.getByName(ip);// 在给定主机名的情况下确定主机的 IP 址。
		byte[] bytes = address.getAddress();// 返回此 InetAddress 对象的原始 IP 地址
		int a, b, c, d;
		a = byte2int(bytes[0]);
		b = byte2int(bytes[1]);
		c = byte2int(bytes[2]);
		d = byte2int(bytes[3]);
		int result = (a << 24) | (b << 16) | (c << 8) | d;
		return result;
	}

	public static int byte2int(byte b) {
		int l = b & 0x07f;
		if (b < 0) {
			l |= 0x80;
		}
		return l;
	}

	/**
	 * @param ip
	 * @return IP转化为长整形数值
	 * @throws UnknownHostException
	 * @author wenc
	 */
	public static long ip2long(String ip) throws Exception {
		int ipNum = ip2Int(ip);
		return int2long(ipNum);
	}

	public static long int2long(int i) {
		long l = i & 0x7fffffffL;
		if (i < 0) {
			l |= 0x080000000L;
		}
		return l;
	}

	/**
	 * @param ip
	 * @return 长整形数值转化为ip地址
	 * @author wenc
	 */
	public static String long2ip(long ip) {
		int[] b = new int[4];
		b[0] = (int) ((ip >> 24) & 0xff);
		b[1] = (int) ((ip >> 16) & 0xff);
		b[2] = (int) ((ip >> 8) & 0xff);
		b[3] = (int) (ip & 0xff);
		String x = Integer.toString(b[0]) + "." + Integer.toString(b[1]) + "." + Integer.toString(b[2]) + "." + Integer.toString(b[3]);
		return x;
	}

}