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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; } }