Mega Code Archive
Converts IPv4 address in its textual presentation form into its numeric binary form
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/*
* Copyright 2004-2005 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
//package sun.net.util;
public class IPAddressUtil {
private final static int INADDR4SZ = 4;
private final static int INADDR16SZ = 16;
private final static int INT16SZ = 2;
/*
* Converts IPv4 address in its textual presentation form
* into its numeric binary form.
*
* @param src a String representing an IPv4 address in standard format
* @return a byte array representing the IPv4 numeric address
*/
public static byte[] textToNumericFormatV4(String src)
{
if (src.length() == 0) {
return null;
}
byte[] res = new byte[INADDR4SZ];
String[] s = src.split("\\.", -1);
long val;
try {
switch(s.length) {
case 1:
/*
* When only one part is given, the value is stored directly in
* the network address without any byte rearrangement.
*/
val = Long.parseLong(s[0]);
if (val < 0 || val > 0xffffffffL)
return null;
res[0] = (byte) ((val >> 24) & 0xff);
res[1] = (byte) (((val & 0xffffff) >> 16) & 0xff);
res[2] = (byte) (((val & 0xffff) >> 8) & 0xff);
res[3] = (byte) (val & 0xff);
break;
case 2:
/*
* When a two part address is supplied, the last part is
* interpreted as a 24-bit quantity and placed in the right
* most three bytes of the network address. This makes the
* two part address format convenient for specifying Class A
* network addresses as net.host.
*/
val = Integer.parseInt(s[0]);
if (val < 0 || val > 0xff)
return null;
res[0] = (byte) (val & 0xff);
val = Integer.parseInt(s[1]);
if (val < 0 || val > 0xffffff)
return null;
res[1] = (byte) ((val >> 16) & 0xff);
res[2] = (byte) (((val & 0xffff) >> 8) &0xff);
res[3] = (byte) (val & 0xff);
break;
case 3:
/*
* When a three part address is specified, the last part is
* interpreted as a 16-bit quantity and placed in the right
* most two bytes of the network address. This makes the
* three part address format convenient for specifying
* Class B net- work addresses as 128.net.host.
*/
for (int i = 0; i < 2; i++) {
val = Integer.parseInt(s[i]);
if (val < 0 || val > 0xff)
return null;
res[i] = (byte) (val & 0xff);
}
val = Integer.parseInt(s[2]);
if (val < 0 || val > 0xffff)
return null;
res[2] = (byte) ((val >> 8) & 0xff);
res[3] = (byte) (val & 0xff);
break;
case 4:
/*
* When four parts are specified, each is interpreted as a
* byte of data and assigned, from left to right, to the
* four bytes of an IPv4 address.
*/
for (int i = 0; i < 4; i++) {
val = Integer.parseInt(s[i]);
if (val < 0 || val > 0xff)
return null;
res[i] = (byte) (val & 0xff);
}
break;
default:
return null;
}
} catch(NumberFormatException e) {
return null;
}
return res;
}
}
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