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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* Copyright 2012 The Netty Project
*
* The Netty Project licenses this file to you under the Apache License,
* version 2.0 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package io.netty.util;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.net.Inet4Address;
import java.net.Inet6Address;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;
import java.util.StringTokenizer;
/**
* A class that holds a number of network-related constants.
*
* This class borrowed some of its methods from a modified fork of the
* Inet6Util class which was part of Apache Harmony.
*/
public final class NetUtil {
/**
* The {@link Inet4Address} that represents the IPv4 loopback address '127.0.0.1'
*/
public static final Inet4Address LOCALHOST4;
/**
* The {@link Inet6Address} that represents the IPv6 loopback address '::1'
*/
public static final Inet6Address LOCALHOST6;
/**
* The {@link InetAddress} that represents the loopback address. If IPv6 stack is available, it will refer to
* {@link #LOCALHOST6}. Otherwise, {@link #LOCALHOST4}.
*/
public static final InetAddress LOCALHOST;
/**
* The loopback {@link NetworkInterface} of the current machine
*/
public static final NetworkInterface LOOPBACK_IF;
/**
* The SOMAXCONN value of the current machine. If failed to get the value, {@code 200} is used as a
* default value for Windows or {@code 128} for others.
*/
public static final int SOMAXCONN;
/**
* This defines how many words (represented as ints) are needed to represent an IPv6 address
*/
private static final int IPV6_WORD_COUNT = 8;
/**
* The maximum number of characters for an IPV6 string with no scope
*/
private static final int IPV6_MAX_CHAR_COUNT = 39;
/**
* Number of bytes needed to represent and IPV6 value
*/
private static final int IPV6_BYTE_COUNT = 16;
/**
* Maximum amount of value adding characters in between IPV6 separators
*/
private static final int IPV6_MAX_CHAR_BETWEEN_SEPARATOR = 4;
/**
* Minimum number of separators that must be present in an IPv6 string
*/
private static final int IPV6_MIN_SEPARATORS = 2;
/**
* Maximum number of separators that must be present in an IPv6 string
*/
private static final int IPV6_MAX_SEPARATORS = 8;
/**
* Number of bytes needed to represent and IPV4 value
*/
private static final int IPV4_BYTE_COUNT = 4;
/**
* Maximum amount of value adding characters in between IPV4 separators
*/
private static final int IPV4_MAX_CHAR_BETWEEN_SEPARATOR = 3;
/**
* Number of separators that must be present in an IPv4 string
*/
private static final int IPV4_SEPARATORS = 3;
/**
* The logger being used by this class
*/
private static final InternalLogger logger = InternalLoggerFactory.getInstance(NetUtil.class);
static {
byte[] LOCALHOST4_BYTES = {127, 0, 0, 1};
byte[] LOCALHOST6_BYTES = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1};
// Create IPv4 loopback address.
Inet4Address localhost4 = null;
try {
localhost4 = (Inet4Address) InetAddress.getByAddress(LOCALHOST4_BYTES);
} catch (Exception e) {
// We should not get here as long as the length of the address is correct.
PlatformDependent.throwException(e);
}
LOCALHOST4 = localhost4;
// Create IPv6 loopback address.
Inet6Address localhost6 = null;
try {
localhost6 = (Inet6Address) InetAddress.getByAddress(LOCALHOST6_BYTES);
} catch (Exception e) {
// We should not get here as long as the length of the address is correct.
PlatformDependent.throwException(e);
}
LOCALHOST6 = localhost6;
// Retrieve the list of available network interfaces.
List ifaces = new ArrayList();
try {
for (Enumeration i = NetworkInterface.getNetworkInterfaces(); i.hasMoreElements();) {
NetworkInterface iface = i.nextElement();
// Use the interface with proper INET addresses only.
if (iface.getInetAddresses().hasMoreElements()) {
ifaces.add(iface);
}
}
} catch (SocketException e) {
logger.warn("Failed to retrieve the list of available network interfaces", e);
}
// Find the first loopback interface available from its INET address (127.0.0.1 or ::1)
// Note that we do not use NetworkInterface.isLoopback() in the first place because it takes long time
// on a certain environment. (e.g. Windows with -Djava.net.preferIPv4Stack=true)
NetworkInterface loopbackIface = null;
InetAddress loopbackAddr = null;
loop: for (NetworkInterface iface: ifaces) {
for (Enumeration i = iface.getInetAddresses(); i.hasMoreElements();) {
InetAddress addr = i.nextElement();
if (addr.isLoopbackAddress()) {
// Found
loopbackIface = iface;
loopbackAddr = addr;
break loop;
}
}
}
// If failed to find the loopback interface from its INET address, fall back to isLoopback().
if (loopbackIface == null) {
try {
for (NetworkInterface iface: ifaces) {
if (iface.isLoopback()) {
Enumeration i = iface.getInetAddresses();
if (i.hasMoreElements()) {
// Found the one with INET address.
loopbackIface = iface;
loopbackAddr = i.nextElement();
break;
}
}
}
if (loopbackIface == null) {
logger.warn("Failed to find the loopback interface");
}
} catch (SocketException e) {
logger.warn("Failed to find the loopback interface", e);
}
}
if (loopbackIface != null) {
// Found the loopback interface with an INET address.
logger.debug(
"Loopback interface: {} ({}, {})",
loopbackIface.getName(), loopbackIface.getDisplayName(), loopbackAddr.getHostAddress());
} else {
// Could not find the loopback interface, but we can't leave LOCALHOST as null.
// Use LOCALHOST6 or LOCALHOST4, preferably the IPv6 one.
if (loopbackAddr == null) {
try {
if (NetworkInterface.getByInetAddress(LOCALHOST6) != null) {
logger.debug("Using hard-coded IPv6 localhost address: {}", localhost6);
loopbackAddr = localhost6;
}
} catch (Exception e) {
// Ignore
} finally {
if (loopbackAddr == null) {
logger.debug("Using hard-coded IPv4 localhost address: {}", localhost4);
loopbackAddr = localhost4;
}
}
}
}
LOOPBACK_IF = loopbackIface;
LOCALHOST = loopbackAddr;
// Determine the default somaxconn (server socket backlog) value of the platform.
// The known defaults:
// - Windows NT Server 4.0+: 200
// - Linux and Mac OS X: 128
int somaxconn = PlatformDependent.isWindows() ? 200 : 128;
File file = new File("/proc/sys/net/core/somaxconn");
if (file.exists()) {
BufferedReader in = null;
try {
in = new BufferedReader(new FileReader(file));
somaxconn = Integer.parseInt(in.readLine());
if (logger.isDebugEnabled()) {
logger.debug("{}: {}", file, somaxconn);
}
} catch (Exception e) {
logger.debug("Failed to get SOMAXCONN from: {}", file, e);
} finally {
if (in != null) {
try {
in.close();
} catch (Exception e) {
// Ignored.
}
}
}
} else {
if (logger.isDebugEnabled()) {
logger.debug("{}: {} (non-existent)", file, somaxconn);
}
}
SOMAXCONN = somaxconn;
}
/**
* Creates an byte[] based on an ipAddressString. No error handling is
* performed here.
*/
public static byte[] createByteArrayFromIpAddressString(String ipAddressString) {
if (isValidIpV4Address(ipAddressString)) {
StringTokenizer tokenizer = new StringTokenizer(ipAddressString, ".");
String token;
int tempInt;
byte[] byteAddress = new byte[IPV4_BYTE_COUNT];
for (int i = 0; i < IPV4_BYTE_COUNT; i ++) {
token = tokenizer.nextToken();
tempInt = Integer.parseInt(token);
byteAddress[i] = (byte) tempInt;
}
return byteAddress;
}
if (isValidIpV6Address(ipAddressString)) {
if (ipAddressString.charAt(0) == '[') {
ipAddressString = ipAddressString.substring(1, ipAddressString.length() - 1);
}
int percentPos = ipAddressString.indexOf('%');
if (percentPos >= 0) {
ipAddressString = ipAddressString.substring(0, percentPos);
}
StringTokenizer tokenizer = new StringTokenizer(ipAddressString, ":.", true);
ArrayList hexStrings = new ArrayList();
ArrayList decStrings = new ArrayList();
String token = "";
String prevToken = "";
int doubleColonIndex = -1; // If a double colon exists, we need to
// insert 0s.
// Go through the tokens, including the seperators ':' and '.'
// When we hit a : or . the previous token will be added to either
// the hex list or decimal list. In the case where we hit a ::
// we will save the index of the hexStrings so we can add zeros
// in to fill out the string
while (tokenizer.hasMoreTokens()) {
prevToken = token;
token = tokenizer.nextToken();
if (":".equals(token)) {
if (":".equals(prevToken)) {
doubleColonIndex = hexStrings.size();
} else if (!prevToken.isEmpty()) {
hexStrings.add(prevToken);
}
} else if (".".equals(token)) {
decStrings.add(prevToken);
}
}
if (":".equals(prevToken)) {
if (":".equals(token)) {
doubleColonIndex = hexStrings.size();
} else {
hexStrings.add(token);
}
} else if (".".equals(prevToken)) {
decStrings.add(token);
}
// figure out how many hexStrings we should have
// also check if it is a IPv4 address
int hexStringsLength = 8;
// If we have an IPv4 address tagged on at the end, subtract
// 4 bytes, or 2 hex words from the total
if (!decStrings.isEmpty()) {
hexStringsLength -= 2;
}
// if we hit a double Colon add the appropriate hex strings
if (doubleColonIndex != -1) {
int numberToInsert = hexStringsLength - hexStrings.size();
for (int i = 0; i < numberToInsert; i ++) {
hexStrings.add(doubleColonIndex, "0");
}
}
byte[] ipByteArray = new byte[IPV6_BYTE_COUNT];
// Finally convert these strings to bytes...
for (int i = 0; i < hexStrings.size(); i ++) {
convertToBytes(hexStrings.get(i), ipByteArray, i << 1);
}
// Now if there are any decimal values, we know where they go...
for (int i = 0; i < decStrings.size(); i ++) {
ipByteArray[i + 12] = (byte) (Integer.parseInt(decStrings.get(i)) & 255);
}
return ipByteArray;
}
return null;
}
/**
* Converts a 4 character hex word into a 2 byte word equivalent
*/
private static void convertToBytes(String hexWord, byte[] ipByteArray, int byteIndex) {
int hexWordLength = hexWord.length();
int hexWordIndex = 0;
ipByteArray[byteIndex] = 0;
ipByteArray[byteIndex + 1] = 0;
int charValue;
// high order 4 bits of first byte
if (hexWordLength > 3) {
charValue = getIntValue(hexWord.charAt(hexWordIndex ++));
ipByteArray[byteIndex] |= charValue << 4;
}
// low order 4 bits of the first byte
if (hexWordLength > 2) {
charValue = getIntValue(hexWord.charAt(hexWordIndex ++));
ipByteArray[byteIndex] |= charValue;
}
// high order 4 bits of second byte
if (hexWordLength > 1) {
charValue = getIntValue(hexWord.charAt(hexWordIndex ++));
ipByteArray[byteIndex + 1] |= charValue << 4;
}
// low order 4 bits of the first byte
charValue = getIntValue(hexWord.charAt(hexWordIndex));
ipByteArray[byteIndex + 1] |= charValue & 15;
}
static int getIntValue(char c) {
switch (c) {
case '0':
return 0;
case '1':
return 1;
case '2':
return 2;
case '3':
return 3;
case '4':
return 4;
case '5':
return 5;
case '6':
return 6;
case '7':
return 7;
case '8':
return 8;
case '9':
return 9;
}
c = Character.toLowerCase(c);
switch (c) {
case 'a':
return 10;
case 'b':
return 11;
case 'c':
return 12;
case 'd':
return 13;
case 'e':
return 14;
case 'f':
return 15;
}
return 0;
}
public static boolean isValidIpV6Address(String ipAddress) {
int length = ipAddress.length();
boolean doubleColon = false;
int numberOfColons = 0;
int numberOfPeriods = 0;
StringBuilder word = new StringBuilder();
char c = 0;
char prevChar;
int startOffset = 0; // offset for [] ip addresses
int endOffset = ipAddress.length();
if (endOffset < 2) {
return false;
}
// Strip []
if (ipAddress.charAt(0) == '[') {
if (ipAddress.charAt(endOffset - 1) != ']') {
return false; // must have a close ]
}
startOffset = 1;
endOffset --;
}
// Strip the interface name/index after the percent sign.
int percentIdx = ipAddress.indexOf('%', startOffset);
if (percentIdx >= 0) {
endOffset = percentIdx;
}
for (int i = startOffset; i < endOffset; i ++) {
prevChar = c;
c = ipAddress.charAt(i);
switch (c) {
// case for the last 32-bits represented as IPv4 x:x:x:x:x:x:d.d.d.d
case '.':
numberOfPeriods ++;
if (numberOfPeriods > 3) {
return false;
}
if (!isValidIp4Word(word.toString())) {
return false;
}
if (numberOfColons != 6 && !doubleColon) {
return false;
}
// a special case ::1:2:3:4:5:d.d.d.d allows 7 colons with an
// IPv4 ending, otherwise 7 :'s is bad
if (numberOfColons == 7 && ipAddress.charAt(startOffset) != ':' &&
ipAddress.charAt(1 + startOffset) != ':') {
return false;
}
word.delete(0, word.length());
break;
case ':':
// FIX "IP6 mechanism syntax #ip6-bad1"
// An IPV6 address cannot start with a single ":".
// Either it can starti with "::" or with a number.
if (i == startOffset && (ipAddress.length() <= i || ipAddress.charAt(i + 1) != ':')) {
return false;
}
// END FIX "IP6 mechanism syntax #ip6-bad1"
numberOfColons ++;
if (numberOfColons > 7) {
return false;
}
if (numberOfPeriods > 0) {
return false;
}
if (prevChar == ':') {
if (doubleColon) {
return false;
}
doubleColon = true;
}
word.delete(0, word.length());
break;
default:
if (word != null && word.length() > 3) {
return false;
}
if (!isValidHexChar(c)) {
return false;
}
word.append(c);
}
}
// Check if we have an IPv4 ending
if (numberOfPeriods > 0) {
// There is a test case with 7 colons and valid ipv4 this should resolve it
if (numberOfPeriods != 3 || !(isValidIp4Word(word.toString()) && numberOfColons < 7)) {
return false;
}
} else {
// If we're at then end and we haven't had 7 colons then there is a
// problem unless we encountered a doubleColon
if (numberOfColons != 7 && !doubleColon) {
return false;
}
// If we have an empty word at the end, it means we ended in either
// a : or a .
// If we did not end in :: then this is invalid
if (word.length() == 0 && ipAddress.charAt(length - 1 - startOffset) == ':' &&
ipAddress.charAt(length - 2 - startOffset) != ':') {
return false;
}
}
return true;
}
/**
* @deprecated Do not use; published by mistake.
*/
@Deprecated
public static boolean isValidIp4Word(String word) {
char c;
if (word.length() < 1 || word.length() > 3) {
return false;
}
for (int i = 0; i < word.length(); i ++) {
c = word.charAt(i);
if (!(c >= '0' && c <= '9')) {
return false;
}
}
return Integer.parseInt(word) <= 255;
}
private static boolean isValidHexChar(char c) {
return c >= '0' && c <= '9' || c >= 'A' && c <= 'F' || c >= 'a' && c <= 'f';
}
private static boolean isValidNumericChar(char c) {
return c >= '0' && c <= '9';
}
/**
* Takes a string and parses it to see if it is a valid IPV4 address.
*
* @return true, if the string represents an IPV4 address in dotted
* notation, false otherwise
*/
public static boolean isValidIpV4Address(String value) {
int periods = 0;
int i;
int length = value.length();
if (length > 15) {
return false;
}
char c;
StringBuilder word = new StringBuilder();
for (i = 0; i < length; i ++) {
c = value.charAt(i);
if (c == '.') {
periods ++;
if (periods > 3) {
return false;
}
if (word.length() == 0) {
return false;
}
if (Integer.parseInt(word.toString()) > 255) {
return false;
}
word.delete(0, word.length());
} else if (!Character.isDigit(c)) {
return false;
} else {
if (word.length() > 2) {
return false;
}
word.append(c);
}
}
if (word.length() == 0 || Integer.parseInt(word.toString()) > 255) {
return false;
}
return periods == 3;
}
/**
* Returns the {@link Inet6Address} representation of a {@link CharSequence} IP address.
*
* This method will treat all IPv4 type addresses as "IPv4 mapped" (see {@link #getByName(CharSequence, boolean)})
* @param ip {@link CharSequence} IP address to be converted to a {@link Inet6Address}
* @return {@link Inet6Address} representation of the {@code ip} or {@code null} if not a valid IP address.
*/
public static Inet6Address getByName(CharSequence ip) {
return getByName(ip, true);
}
/**
* Returns the {@link Inet6Address} representation of a {@link CharSequence} IP address.
*
* The {@code ipv4Mapped} parameter specifies how IPv4 addresses should be treated.
* "IPv4 mapped" format as
* defined in rfc 4291 section 2 is supported.
* @param ip {@link CharSequence} IP address to be converted to a {@link Inet6Address}
* @param ipv4Mapped
*
* - {@code true} To allow IPv4 mapped inputs to be translated into {@link Inet6Address}
* - {@code false} Don't turn IPv4 addressed to mapped addresses
*
* @return {@link Inet6Address} representation of the {@code ip} or {@code null} if not a valid IP address.
*/
public static Inet6Address getByName(CharSequence ip, boolean ipv4Mapped) {
final byte[] bytes = new byte[IPV6_BYTE_COUNT];
final int ipLength = ip.length();
int compressBegin = 0;
int compressLength = 0;
int currentIndex = 0;
int value = 0;
int begin = -1;
int i = 0;
int ipv6Seperators = 0;
int ipv4Seperators = 0;
int tmp;
boolean needsShift = false;
for (; i < ipLength; ++i) {
final char c = ip.charAt(i);
switch (c) {
case ':':
++ipv6Seperators;
if (i - begin > IPV6_MAX_CHAR_BETWEEN_SEPARATOR ||
ipv4Seperators > 0 || ipv6Seperators > IPV6_MAX_SEPARATORS ||
currentIndex + 1 >= bytes.length) {
return null;
}
value <<= (IPV6_MAX_CHAR_BETWEEN_SEPARATOR - (i - begin)) << 2;
if (compressLength > 0) {
compressLength -= 2;
}
// The value integer holds at most 4 bytes from right (most significant) to left (least significant).
// The following bit shifting is used to extract and re-order the individual bytes to achieve a
// left (most significant) to right (least significant) ordering.
bytes[currentIndex++] = (byte) (((value & 0xf) << 4) | ((value >> 4) & 0xf));
bytes[currentIndex++] = (byte) ((((value >> 8) & 0xf) << 4) | ((value >> 12) & 0xf));
tmp = i + 1;
if (tmp < ipLength && ip.charAt(tmp) == ':') {
++tmp;
if (compressBegin != 0 || (tmp < ipLength && ip.charAt(tmp) == ':')) {
return null;
}
++ipv6Seperators;
needsShift = ipv6Seperators == 2 && value == 0;
compressBegin = currentIndex;
compressLength = bytes.length - compressBegin - 2;
++i;
}
value = 0;
begin = -1;
break;
case '.':
++ipv4Seperators;
if (i - begin > IPV4_MAX_CHAR_BETWEEN_SEPARATOR
|| ipv4Seperators > IPV4_SEPARATORS
|| (ipv6Seperators > 0 && (currentIndex + compressLength < 12))
|| i + 1 >= ipLength
|| currentIndex >= bytes.length
|| begin < 0
|| (begin == 0 && (i == 3 && (!isValidNumericChar(ip.charAt(2)) ||
!isValidNumericChar(ip.charAt(1)) ||
!isValidNumericChar(ip.charAt(0))) ||
i == 2 && (!isValidNumericChar(ip.charAt(1)) ||
!isValidNumericChar(ip.charAt(0))) ||
i == 1 && !isValidNumericChar(ip.charAt(0))))) {
return null;
}
value <<= (IPV4_MAX_CHAR_BETWEEN_SEPARATOR - (i - begin)) << 2;
// The value integer holds at most 3 bytes from right (most significant) to left (least significant).
// The following bit shifting is to restructure the bytes to be left (most significant) to
// right (least significant) while also accounting for each IPv4 digit is base 10.
begin = (value & 0xf) * 100 + ((value >> 4) & 0xf) * 10 + ((value >> 8) & 0xf);
if (begin < 0 || begin > 255) {
return null;
}
bytes[currentIndex++] = (byte) begin;
value = 0;
begin = -1;
break;
default:
if (!isValidHexChar(c) || (ipv4Seperators > 0 && !isValidNumericChar(c))) {
return null;
}
if (begin < 0) {
begin = i;
} else if (i - begin > IPV6_MAX_CHAR_BETWEEN_SEPARATOR) {
return null;
}
// The value is treated as a sort of array of numbers because we are dealing with
// at most 4 consecutive bytes we can use bit shifting to accomplish this.
// The most significant byte will be encountered first, and reside in the right most
// position of the following integer
value += getIntValue(c) << ((i - begin) << 2);
break;
}
}
final boolean isCompressed = compressBegin > 0;
// Finish up last set of data that was accumulated in the loop (or before the loop)
if (ipv4Seperators > 0) {
if (begin > 0 && i - begin > IPV4_MAX_CHAR_BETWEEN_SEPARATOR ||
ipv4Seperators != IPV4_SEPARATORS ||
currentIndex >= bytes.length) {
return null;
}
if (ipv6Seperators == 0) {
compressLength = 12;
} else if (ipv6Seperators >= IPV6_MIN_SEPARATORS &&
ip.charAt(ipLength - 1) != ':' &&
(!isCompressed && (ipv6Seperators == 6 && ip.charAt(0) != ':') ||
isCompressed && (ipv6Seperators + 1 < IPV6_MAX_SEPARATORS &&
(ip.charAt(0) != ':' || compressBegin <= 2)))) {
compressLength -= 2;
} else {
return null;
}
value <<= (IPV4_MAX_CHAR_BETWEEN_SEPARATOR - (i - begin)) << 2;
// The value integer holds at most 3 bytes from right (most significant) to left (least significant).
// The following bit shifting is to restructure the bytes to be left (most significant) to
// right (least significant) while also accounting for each IPv4 digit is base 10.
begin = (value & 0xf) * 100 + ((value >> 4) & 0xf) * 10 + ((value >> 8) & 0xf);
if (begin < 0 || begin > 255) {
return null;
}
bytes[currentIndex++] = (byte) begin;
} else {
tmp = ipLength - 1;
if (begin > 0 && i - begin > IPV6_MAX_CHAR_BETWEEN_SEPARATOR ||
ipv6Seperators < IPV6_MIN_SEPARATORS ||
!isCompressed && (ipv6Seperators + 1 != IPV6_MAX_SEPARATORS ||
ip.charAt(0) == ':' || ip.charAt(tmp) == ':') ||
isCompressed && (ipv6Seperators > IPV6_MAX_SEPARATORS ||
(ipv6Seperators == IPV6_MAX_SEPARATORS &&
(compressBegin <= 2 && ip.charAt(0) != ':' ||
compressBegin >= 14 && ip.charAt(tmp) != ':'))) ||
currentIndex + 1 >= bytes.length) {
return null;
}
if (begin >= 0 && i - begin <= IPV6_MAX_CHAR_BETWEEN_SEPARATOR) {
value <<= (IPV6_MAX_CHAR_BETWEEN_SEPARATOR - (i - begin)) << 2;
}
// The value integer holds at most 4 bytes from right (most significant) to left (least significant).
// The following bit shifting is used to extract and re-order the individual bytes to achieve a
// left (most significant) to right (least significant) ordering.
bytes[currentIndex++] = (byte) (((value & 0xf) << 4) | ((value >> 4) & 0xf));
bytes[currentIndex++] = (byte) ((((value >> 8) & 0xf) << 4) | ((value >> 12) & 0xf));
}
i = currentIndex + compressLength;
if (needsShift || i >= bytes.length) {
// Right shift array
if (i >= bytes.length) {
++compressBegin;
}
for (i = currentIndex; i < bytes.length; ++i) {
for (begin = bytes.length - 1; begin >= compressBegin; --begin) {
bytes[begin] = bytes[begin - 1];
}
bytes[begin] = 0;
++compressBegin;
}
} else {
// Selectively move elements
for (i = 0; i < compressLength; ++i) {
begin = i + compressBegin;
currentIndex = begin + compressLength;
if (currentIndex < bytes.length) {
bytes[currentIndex] = bytes[begin];
bytes[begin] = 0;
} else {
break;
}
}
}
if (ipv4Mapped && ipv4Seperators > 0 &&
bytes[0] == 0 && bytes[1] == 0 && bytes[2] == 0 && bytes[3] == 0 && bytes[4] == 0 &&
bytes[5] == 0 && bytes[6] == 0 && bytes[7] == 0 && bytes[8] == 0 && bytes[9] == 0) {
bytes[10] = bytes[11] = (byte) 0xff;
}
try {
return Inet6Address.getByAddress(null, bytes, -1);
} catch (UnknownHostException e) {
throw new RuntimeException(e); // Should never happen
}
}
/**
* Returns the {@link String} representation of an {@link InetAddress}.
*
* - Inet4Address results are identical to {@link InetAddress#getHostAddress()}
* - Inet6Address results adhere to
* rfc 5952 section 4
*
*
* The output does not include Scope ID.
* @param ip {@link InetAddress} to be converted to an address string
* @return {@code String} containing the text-formatted IP address
*/
public static String toAddressString(InetAddress ip) {
return toAddressString(ip, false);
}
/**
* Returns the {@link String} representation of an {@link InetAddress}.
*
* - Inet4Address results are identical to {@link InetAddress#getHostAddress()}
* - Inet6Address results adhere to
* rfc 5952 section 4 if
* {@code ipv4Mapped} is false. If {@code ipv4Mapped} is true then "IPv4 mapped" format
* from rfc 4291 section 2 will be supported.
* The compressed result will always obey the compression rules defined in
* rfc 5952 section 4
*
*
* The output does not include Scope ID.
* @param ip {@link InetAddress} to be converted to an address string
* @param ipv4Mapped
*
* - {@code true} to stray from strict rfc 5952 and support the "IPv4 mapped" format
* defined in rfc 4291 section 2 while still
* following the updated guidelines in
* rfc 5952 section 4
* - {@code false} to strictly follow rfc 5952
*
* @return {@code String} containing the text-formatted IP address
*/
public static String toAddressString(InetAddress ip, boolean ipv4Mapped) {
if (ip instanceof Inet4Address) {
return ip.getHostAddress();
}
if (!(ip instanceof Inet6Address)) {
throw new IllegalArgumentException("Unhandled type: " + ip.getClass());
}
final byte[] bytes = ip.getAddress();
final int[] words = new int[IPV6_WORD_COUNT];
int i;
for (i = 0; i < words.length; ++i) {
words[i] = ((bytes[i << 1] & 0xff) << 8) | (bytes[(i << 1) + 1] & 0xff);
}
// Find longest run of 0s, tie goes to first found instance
int currentStart = -1;
int currentLength = 0;
int shortestStart = -1;
int shortestLength = 0;
for (i = 0; i < words.length; ++i) {
if (words[i] == 0) {
if (currentStart < 0) {
currentStart = i;
}
} else if (currentStart >= 0) {
currentLength = i - currentStart;
if (currentLength > shortestLength) {
shortestStart = currentStart;
shortestLength = currentLength;
}
currentStart = -1;
}
}
// If the array ends on a streak of zeros, make sure we account for it
if (currentStart >= 0) {
currentLength = i - currentStart;
if (currentLength > shortestLength) {
shortestStart = currentStart;
shortestLength = currentLength;
}
}
// Ignore the longest streak if it is only 1 long
if (shortestLength == 1) {
shortestLength = 0;
shortestStart = -1;
}
// Translate to string taking into account longest consecutive 0s
final int shortestEnd = shortestStart + shortestLength;
final StringBuilder b = new StringBuilder(IPV6_MAX_CHAR_COUNT);
if (shortestEnd < 0) { // Optimization when there is no compressing needed
b.append(Integer.toHexString(words[0]));
for (i = 1; i < words.length; ++i) {
b.append(':');
b.append(Integer.toHexString(words[i]));
}
} else { // General case that can handle compressing (and not compressing)
// Loop unroll the first index (so we don't constantly check i==0 cases in loop)
final boolean isIpv4Mapped;
if (inRangeEndExclusive(0, shortestStart, shortestEnd)) {
b.append("::");
isIpv4Mapped = ipv4Mapped && (shortestEnd == 5 && words[5] == 0xffff);
} else {
b.append(Integer.toHexString(words[0]));
isIpv4Mapped = false;
}
for (i = 1; i < words.length; ++i) {
if (!inRangeEndExclusive(i, shortestStart, shortestEnd)) {
if (!inRangeEndExclusive(i - 1, shortestStart, shortestEnd)) {
// If the last index was not part of the shortened sequence
if (!isIpv4Mapped || i == 6) {
b.append(':');
} else {
b.append('.');
}
}
if (isIpv4Mapped && i > 5) {
b.append(words[i] >> 8);
b.append('.');
b.append(words[i] & 0xff);
} else {
b.append(Integer.toHexString(words[i]));
}
} else if (!inRangeEndExclusive(i - 1, shortestStart, shortestEnd)) {
// If we are in the shortened sequence and the last index was not
b.append("::");
}
}
}
return b.toString();
}
/**
* Does a range check on {@code value} if is within {@code start} (inclusive) and {@code end} (exclusive).
* @param value The value to checked if is within {@code start} (inclusive) and {@code end} (exclusive)
* @param start The start of the range (inclusive)
* @param end The end of the range (exclusive)
* @return
*
* - {@code true} if {@code value} if is within {@code start} (inclusive) and {@code end} (exclusive)
* - {@code false} otherwise
*
*/
private static boolean inRangeEndExclusive(int value, int start, int end) {
return value >= start && value < end;
}
/**
* A constructor to stop this class being constructed.
*/
private NetUtil() {
// Unused
}
}