字符型ip地址与int型ip地址的互相转换

[java]代码库

/**
 * 字符型ip地址与int型ip的互相转换
 */
public class IpUtil
{

	/**
	 * 将字符串型ip转成int型ip
	 * @param strIp
	 * @return
	 */
	public static int Ip2Int ( String strIp )
	{
		String[] ss = strIp.split ( "\\." );
		if ( ss.length != 4 )
		{
			return 0;
		}
		byte[] bytes = new byte[ss.length];
		for ( int i = 0; i < bytes.length; i++ )
		{
			bytes[i] = ( byte ) Integer.parseInt ( ss[i] );
		}
		return byte2Int ( bytes );
	}
	/**
	 * 将int型ip转成String型ip
	 * @param intIp
	 * @return
	 */
	public static String int2Ip ( int intIp )
	{
		byte[] bytes = int2byte ( intIp );
		StringBuilder sb = new StringBuilder();
		for ( int i = 0; i < 4; i++ )
		{
			sb.append ( bytes[i] & 0xFF );
			if ( i < 3 )
			{
				sb.append ( "." );
			}
		}
		return sb.toString();
	}

	private static byte[] int2byte ( int i )
	{
		byte[] bytes = new byte[4];
		bytes[0] = ( byte ) ( 0xff & i );
		bytes[1] = ( byte ) ( ( 0xff00 & i ) >> 8 );
		bytes[2] = ( byte ) ( ( 0xff0000 & i ) >> 16 );
		bytes[3] = ( byte ) ( ( 0xff000000 & i ) >> 24 );
		return bytes;
	}
	private static int byte2Int ( byte[] bytes )
	{
		int n = bytes[0] & 0xFF;
		n |= ( ( bytes[1] << 8 ) & 0xFF00 );
		n |= ( ( bytes[2] << 16 ) & 0xFF0000 );
		n |= ( ( bytes[3] << 24 ) & 0xFF000000 );
		return n;
	}

	public static void main ( String[] args )
	{
		String ip1 = "192.168.0.1";
		int intIp = Ip2Int ( ip1 );
		String ip2 = int2Ip ( intIp );
		System.out.println ( ip2.equals ( ip1 ) );
	}
}