--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.base/share/classes/java/net/InetAddress.java Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,1765 @@
+/*
+ * Copyright (c) 1995, 2017, Oracle and/or its affiliates. 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. Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package java.net;
+
+import java.util.NavigableSet;
+import java.util.ArrayList;
+import java.util.Objects;
+import java.util.Scanner;
+import java.security.AccessController;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.ObjectStreamException;
+import java.io.ObjectStreamField;
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectInputStream.GetField;
+import java.io.ObjectOutputStream;
+import java.io.ObjectOutputStream.PutField;
+import java.lang.annotation.Native;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.ConcurrentSkipListSet;
+import java.util.concurrent.atomic.AtomicLong;
+
+import jdk.internal.misc.JavaNetInetAddressAccess;
+import jdk.internal.misc.SharedSecrets;
+import sun.security.action.*;
+import sun.net.InetAddressCachePolicy;
+import sun.net.util.IPAddressUtil;
+
+/**
+ * This class represents an Internet Protocol (IP) address.
+ *
+ * <p> An IP address is either a 32-bit or 128-bit unsigned number
+ * used by IP, a lower-level protocol on which protocols like UDP and
+ * TCP are built. The IP address architecture is defined by <a
+ * href="http://www.ietf.org/rfc/rfc790.txt"><i>RFC 790:
+ * Assigned Numbers</i></a>, <a
+ * href="http://www.ietf.org/rfc/rfc1918.txt"> <i>RFC 1918:
+ * Address Allocation for Private Internets</i></a>, <a
+ * href="http://www.ietf.org/rfc/rfc2365.txt"><i>RFC 2365:
+ * Administratively Scoped IP Multicast</i></a>, and <a
+ * href="http://www.ietf.org/rfc/rfc2373.txt"><i>RFC 2373: IP
+ * Version 6 Addressing Architecture</i></a>. An instance of an
+ * InetAddress consists of an IP address and possibly its
+ * corresponding host name (depending on whether it is constructed
+ * with a host name or whether it has already done reverse host name
+ * resolution).
+ *
+ * <h3> Address types </h3>
+ *
+ * <table class="striped" style="margin-left:2em">
+ * <caption style="display:none">Description of unicast and multicast address types</caption>
+ * <thead>
+ * <tr><th scope="col">Address Type</th><th scope="col">Description</th></tr>
+ * </thead>
+ * <tbody>
+ * <tr><th scope="row" style="vertical-align:top">unicast</th>
+ * <td>An identifier for a single interface. A packet sent to
+ * a unicast address is delivered to the interface identified by
+ * that address.
+ *
+ * <p> The Unspecified Address -- Also called anylocal or wildcard
+ * address. It must never be assigned to any node. It indicates the
+ * absence of an address. One example of its use is as the target of
+ * bind, which allows a server to accept a client connection on any
+ * interface, in case the server host has multiple interfaces.
+ *
+ * <p> The <i>unspecified</i> address must not be used as
+ * the destination address of an IP packet.
+ *
+ * <p> The <i>Loopback</i> Addresses -- This is the address
+ * assigned to the loopback interface. Anything sent to this
+ * IP address loops around and becomes IP input on the local
+ * host. This address is often used when testing a
+ * client.</td></tr>
+ * <tr><th scope="row" style="vertical-align:top">multicast</th>
+ * <td>An identifier for a set of interfaces (typically belonging
+ * to different nodes). A packet sent to a multicast address is
+ * delivered to all interfaces identified by that address.</td></tr>
+ * </tbody>
+ * </table>
+ *
+ * <h4> IP address scope </h4>
+ *
+ * <p> <i>Link-local</i> addresses are designed to be used for addressing
+ * on a single link for purposes such as auto-address configuration,
+ * neighbor discovery, or when no routers are present.
+ *
+ * <p> <i>Site-local</i> addresses are designed to be used for addressing
+ * inside of a site without the need for a global prefix.
+ *
+ * <p> <i>Global</i> addresses are unique across the internet.
+ *
+ * <h4> Textual representation of IP addresses </h4>
+ *
+ * The textual representation of an IP address is address family specific.
+ *
+ * <p>
+ *
+ * For IPv4 address format, please refer to <A
+ * HREF="Inet4Address.html#format">Inet4Address#format</A>; For IPv6
+ * address format, please refer to <A
+ * HREF="Inet6Address.html#format">Inet6Address#format</A>.
+ *
+ * <P>There is a <a href="doc-files/net-properties.html#Ipv4IPv6">couple of
+ * System Properties</a> affecting how IPv4 and IPv6 addresses are used.</P>
+ *
+ * <h4> Host Name Resolution </h4>
+ *
+ * Host name-to-IP address <i>resolution</i> is accomplished through
+ * the use of a combination of local machine configuration information
+ * and network naming services such as the Domain Name System (DNS)
+ * and Network Information Service(NIS). The particular naming
+ * services(s) being used is by default the local machine configured
+ * one. For any host name, its corresponding IP address is returned.
+ *
+ * <p> <i>Reverse name resolution</i> means that for any IP address,
+ * the host associated with the IP address is returned.
+ *
+ * <p> The InetAddress class provides methods to resolve host names to
+ * their IP addresses and vice versa.
+ *
+ * <h4> InetAddress Caching </h4>
+ *
+ * The InetAddress class has a cache to store successful as well as
+ * unsuccessful host name resolutions.
+ *
+ * <p> By default, when a security manager is installed, in order to
+ * protect against DNS spoofing attacks,
+ * the result of positive host name resolutions are
+ * cached forever. When a security manager is not installed, the default
+ * behavior is to cache entries for a finite (implementation dependent)
+ * period of time. The result of unsuccessful host
+ * name resolution is cached for a very short period of time (10
+ * seconds) to improve performance.
+ *
+ * <p> If the default behavior is not desired, then a Java security property
+ * can be set to a different Time-to-live (TTL) value for positive
+ * caching. Likewise, a system admin can configure a different
+ * negative caching TTL value when needed.
+ *
+ * <p> Two Java security properties control the TTL values used for
+ * positive and negative host name resolution caching:
+ *
+ * <dl style="margin-left:2em">
+ * <dt><b>networkaddress.cache.ttl</b></dt>
+ * <dd>Indicates the caching policy for successful name lookups from
+ * the name service. The value is specified as an integer to indicate
+ * the number of seconds to cache the successful lookup. The default
+ * setting is to cache for an implementation specific period of time.
+ * <p>
+ * A value of -1 indicates "cache forever".
+ * </dd>
+ * <dt><b>networkaddress.cache.negative.ttl</b> (default: 10)</dt>
+ * <dd>Indicates the caching policy for un-successful name lookups
+ * from the name service. The value is specified as an integer to
+ * indicate the number of seconds to cache the failure for
+ * un-successful lookups.
+ * <p>
+ * A value of 0 indicates "never cache".
+ * A value of -1 indicates "cache forever".
+ * </dd>
+ * </dl>
+ *
+ * @author Chris Warth
+ * @see java.net.InetAddress#getByAddress(byte[])
+ * @see java.net.InetAddress#getByAddress(java.lang.String, byte[])
+ * @see java.net.InetAddress#getAllByName(java.lang.String)
+ * @see java.net.InetAddress#getByName(java.lang.String)
+ * @see java.net.InetAddress#getLocalHost()
+ * @since 1.0
+ */
+public
+class InetAddress implements java.io.Serializable {
+
+ @Native static final int PREFER_IPV4_VALUE = 0;
+ @Native static final int PREFER_IPV6_VALUE = 1;
+ @Native static final int PREFER_SYSTEM_VALUE = 2;
+
+ /**
+ * Specify the address family: Internet Protocol, Version 4
+ * @since 1.4
+ */
+ @Native static final int IPv4 = 1;
+
+ /**
+ * Specify the address family: Internet Protocol, Version 6
+ * @since 1.4
+ */
+ @Native static final int IPv6 = 2;
+
+ /* Specify address family preference */
+ static transient final int preferIPv6Address;
+
+ static class InetAddressHolder {
+ /**
+ * Reserve the original application specified hostname.
+ *
+ * The original hostname is useful for domain-based endpoint
+ * identification (see RFC 2818 and RFC 6125). If an address
+ * was created with a raw IP address, a reverse name lookup
+ * may introduce endpoint identification security issue via
+ * DNS forging.
+ *
+ * Oracle JSSE provider is using this original hostname, via
+ * jdk.internal.misc.JavaNetAccess, for SSL/TLS endpoint identification.
+ *
+ * Note: May define a new public method in the future if necessary.
+ */
+ String originalHostName;
+
+ InetAddressHolder() {}
+
+ InetAddressHolder(String hostName, int address, int family) {
+ this.originalHostName = hostName;
+ this.hostName = hostName;
+ this.address = address;
+ this.family = family;
+ }
+
+ void init(String hostName, int family) {
+ this.originalHostName = hostName;
+ this.hostName = hostName;
+ if (family != -1) {
+ this.family = family;
+ }
+ }
+
+ String hostName;
+
+ String getHostName() {
+ return hostName;
+ }
+
+ String getOriginalHostName() {
+ return originalHostName;
+ }
+
+ /**
+ * Holds a 32-bit IPv4 address.
+ */
+ int address;
+
+ int getAddress() {
+ return address;
+ }
+
+ /**
+ * Specifies the address family type, for instance, '1' for IPv4
+ * addresses, and '2' for IPv6 addresses.
+ */
+ int family;
+
+ int getFamily() {
+ return family;
+ }
+ }
+
+ /* Used to store the serializable fields of InetAddress */
+ final transient InetAddressHolder holder;
+
+ InetAddressHolder holder() {
+ return holder;
+ }
+
+ /* Used to store the name service provider */
+ private static transient NameService nameService = null;
+
+ /* Used to store the best available hostname */
+ private transient String canonicalHostName = null;
+
+ /** use serialVersionUID from JDK 1.0.2 for interoperability */
+ private static final long serialVersionUID = 3286316764910316507L;
+
+ /*
+ * Load net library into runtime, and perform initializations.
+ */
+ static {
+ String str = java.security.AccessController.doPrivileged(
+ new GetPropertyAction("java.net.preferIPv6Addresses"));
+ if (str == null) {
+ preferIPv6Address = PREFER_IPV4_VALUE;
+ } else if (str.equalsIgnoreCase("true")) {
+ preferIPv6Address = PREFER_IPV6_VALUE;
+ } else if (str.equalsIgnoreCase("false")) {
+ preferIPv6Address = PREFER_IPV4_VALUE;
+ } else if (str.equalsIgnoreCase("system")) {
+ preferIPv6Address = PREFER_SYSTEM_VALUE;
+ } else {
+ preferIPv6Address = PREFER_IPV4_VALUE;
+ }
+ AccessController.doPrivileged(
+ new java.security.PrivilegedAction<>() {
+ public Void run() {
+ System.loadLibrary("net");
+ return null;
+ }
+ });
+ SharedSecrets.setJavaNetInetAddressAccess(
+ new JavaNetInetAddressAccess() {
+ public String getOriginalHostName(InetAddress ia) {
+ return ia.holder.getOriginalHostName();
+ }
+
+ public InetAddress getByName(String hostName,
+ InetAddress hostAddress)
+ throws UnknownHostException
+ {
+ return InetAddress.getByName(hostName, hostAddress);
+ }
+ }
+ );
+ init();
+ }
+
+ /**
+ * Constructor for the Socket.accept() method.
+ * This creates an empty InetAddress, which is filled in by
+ * the accept() method. This InetAddress, however, is not
+ * put in the address cache, since it is not created by name.
+ */
+ InetAddress() {
+ holder = new InetAddressHolder();
+ }
+
+ /**
+ * Replaces the de-serialized object with an Inet4Address object.
+ *
+ * @return the alternate object to the de-serialized object.
+ *
+ * @throws ObjectStreamException if a new object replacing this
+ * object could not be created
+ */
+ private Object readResolve() throws ObjectStreamException {
+ // will replace the deserialized 'this' object
+ return new Inet4Address(holder().getHostName(), holder().getAddress());
+ }
+
+ /**
+ * Utility routine to check if the InetAddress is an
+ * IP multicast address.
+ * @return a {@code boolean} indicating if the InetAddress is
+ * an IP multicast address
+ * @since 1.1
+ */
+ public boolean isMulticastAddress() {
+ return false;
+ }
+
+ /**
+ * Utility routine to check if the InetAddress is a wildcard address.
+ * @return a {@code boolean} indicating if the Inetaddress is
+ * a wildcard address.
+ * @since 1.4
+ */
+ public boolean isAnyLocalAddress() {
+ return false;
+ }
+
+ /**
+ * Utility routine to check if the InetAddress is a loopback address.
+ *
+ * @return a {@code boolean} indicating if the InetAddress is
+ * a loopback address; or false otherwise.
+ * @since 1.4
+ */
+ public boolean isLoopbackAddress() {
+ return false;
+ }
+
+ /**
+ * Utility routine to check if the InetAddress is an link local address.
+ *
+ * @return a {@code boolean} indicating if the InetAddress is
+ * a link local address; or false if address is not a link local unicast address.
+ * @since 1.4
+ */
+ public boolean isLinkLocalAddress() {
+ return false;
+ }
+
+ /**
+ * Utility routine to check if the InetAddress is a site local address.
+ *
+ * @return a {@code boolean} indicating if the InetAddress is
+ * a site local address; or false if address is not a site local unicast address.
+ * @since 1.4
+ */
+ public boolean isSiteLocalAddress() {
+ return false;
+ }
+
+ /**
+ * Utility routine to check if the multicast address has global scope.
+ *
+ * @return a {@code boolean} indicating if the address has
+ * is a multicast address of global scope, false if it is not
+ * of global scope or it is not a multicast address
+ * @since 1.4
+ */
+ public boolean isMCGlobal() {
+ return false;
+ }
+
+ /**
+ * Utility routine to check if the multicast address has node scope.
+ *
+ * @return a {@code boolean} indicating if the address has
+ * is a multicast address of node-local scope, false if it is not
+ * of node-local scope or it is not a multicast address
+ * @since 1.4
+ */
+ public boolean isMCNodeLocal() {
+ return false;
+ }
+
+ /**
+ * Utility routine to check if the multicast address has link scope.
+ *
+ * @return a {@code boolean} indicating if the address has
+ * is a multicast address of link-local scope, false if it is not
+ * of link-local scope or it is not a multicast address
+ * @since 1.4
+ */
+ public boolean isMCLinkLocal() {
+ return false;
+ }
+
+ /**
+ * Utility routine to check if the multicast address has site scope.
+ *
+ * @return a {@code boolean} indicating if the address has
+ * is a multicast address of site-local scope, false if it is not
+ * of site-local scope or it is not a multicast address
+ * @since 1.4
+ */
+ public boolean isMCSiteLocal() {
+ return false;
+ }
+
+ /**
+ * Utility routine to check if the multicast address has organization scope.
+ *
+ * @return a {@code boolean} indicating if the address has
+ * is a multicast address of organization-local scope,
+ * false if it is not of organization-local scope
+ * or it is not a multicast address
+ * @since 1.4
+ */
+ public boolean isMCOrgLocal() {
+ return false;
+ }
+
+
+ /**
+ * Test whether that address is reachable. Best effort is made by the
+ * implementation to try to reach the host, but firewalls and server
+ * configuration may block requests resulting in a unreachable status
+ * while some specific ports may be accessible.
+ * A typical implementation will use ICMP ECHO REQUESTs if the
+ * privilege can be obtained, otherwise it will try to establish
+ * a TCP connection on port 7 (Echo) of the destination host.
+ * <p>
+ * The timeout value, in milliseconds, indicates the maximum amount of time
+ * the try should take. If the operation times out before getting an
+ * answer, the host is deemed unreachable. A negative value will result
+ * in an IllegalArgumentException being thrown.
+ *
+ * @param timeout the time, in milliseconds, before the call aborts
+ * @return a {@code boolean} indicating if the address is reachable.
+ * @throws IOException if a network error occurs
+ * @throws IllegalArgumentException if {@code timeout} is negative.
+ * @since 1.5
+ */
+ public boolean isReachable(int timeout) throws IOException {
+ return isReachable(null, 0 , timeout);
+ }
+
+ /**
+ * Test whether that address is reachable. Best effort is made by the
+ * implementation to try to reach the host, but firewalls and server
+ * configuration may block requests resulting in a unreachable status
+ * while some specific ports may be accessible.
+ * A typical implementation will use ICMP ECHO REQUESTs if the
+ * privilege can be obtained, otherwise it will try to establish
+ * a TCP connection on port 7 (Echo) of the destination host.
+ * <p>
+ * The {@code network interface} and {@code ttl} parameters
+ * let the caller specify which network interface the test will go through
+ * and the maximum number of hops the packets should go through.
+ * A negative value for the {@code ttl} will result in an
+ * IllegalArgumentException being thrown.
+ * <p>
+ * The timeout value, in milliseconds, indicates the maximum amount of time
+ * the try should take. If the operation times out before getting an
+ * answer, the host is deemed unreachable. A negative value will result
+ * in an IllegalArgumentException being thrown.
+ *
+ * @param netif the NetworkInterface through which the
+ * test will be done, or null for any interface
+ * @param ttl the maximum numbers of hops to try or 0 for the
+ * default
+ * @param timeout the time, in milliseconds, before the call aborts
+ * @throws IllegalArgumentException if either {@code timeout}
+ * or {@code ttl} are negative.
+ * @return a {@code boolean}indicating if the address is reachable.
+ * @throws IOException if a network error occurs
+ * @since 1.5
+ */
+ public boolean isReachable(NetworkInterface netif, int ttl,
+ int timeout) throws IOException {
+ if (ttl < 0)
+ throw new IllegalArgumentException("ttl can't be negative");
+ if (timeout < 0)
+ throw new IllegalArgumentException("timeout can't be negative");
+
+ return impl.isReachable(this, timeout, netif, ttl);
+ }
+
+ /**
+ * Gets the host name for this IP address.
+ *
+ * <p>If this InetAddress was created with a host name,
+ * this host name will be remembered and returned;
+ * otherwise, a reverse name lookup will be performed
+ * and the result will be returned based on the system
+ * configured name lookup service. If a lookup of the name service
+ * is required, call
+ * {@link #getCanonicalHostName() getCanonicalHostName}.
+ *
+ * <p>If there is a security manager, its
+ * {@code checkConnect} method is first called
+ * with the hostname and {@code -1}
+ * as its arguments to see if the operation is allowed.
+ * If the operation is not allowed, it will return
+ * the textual representation of the IP address.
+ *
+ * @return the host name for this IP address, or if the operation
+ * is not allowed by the security check, the textual
+ * representation of the IP address.
+ *
+ * @see InetAddress#getCanonicalHostName
+ * @see SecurityManager#checkConnect
+ */
+ public String getHostName() {
+ return getHostName(true);
+ }
+
+ /**
+ * Returns the hostname for this address.
+ * If the host is equal to null, then this address refers to any
+ * of the local machine's available network addresses.
+ * this is package private so SocketPermission can make calls into
+ * here without a security check.
+ *
+ * <p>If there is a security manager, this method first
+ * calls its {@code checkConnect} method
+ * with the hostname and {@code -1}
+ * as its arguments to see if the calling code is allowed to know
+ * the hostname for this IP address, i.e., to connect to the host.
+ * If the operation is not allowed, it will return
+ * the textual representation of the IP address.
+ *
+ * @return the host name for this IP address, or if the operation
+ * is not allowed by the security check, the textual
+ * representation of the IP address.
+ *
+ * @param check make security check if true
+ *
+ * @see SecurityManager#checkConnect
+ */
+ String getHostName(boolean check) {
+ if (holder().getHostName() == null) {
+ holder().hostName = InetAddress.getHostFromNameService(this, check);
+ }
+ return holder().getHostName();
+ }
+
+ /**
+ * Gets the fully qualified domain name for this IP address.
+ * Best effort method, meaning we may not be able to return
+ * the FQDN depending on the underlying system configuration.
+ *
+ * <p>If there is a security manager, this method first
+ * calls its {@code checkConnect} method
+ * with the hostname and {@code -1}
+ * as its arguments to see if the calling code is allowed to know
+ * the hostname for this IP address, i.e., to connect to the host.
+ * If the operation is not allowed, it will return
+ * the textual representation of the IP address.
+ *
+ * @return the fully qualified domain name for this IP address,
+ * or if the operation is not allowed by the security check,
+ * the textual representation of the IP address.
+ *
+ * @see SecurityManager#checkConnect
+ *
+ * @since 1.4
+ */
+ public String getCanonicalHostName() {
+ if (canonicalHostName == null) {
+ canonicalHostName =
+ InetAddress.getHostFromNameService(this, true);
+ }
+ return canonicalHostName;
+ }
+
+ /**
+ * Returns the hostname for this address.
+ *
+ * <p>If there is a security manager, this method first
+ * calls its {@code checkConnect} method
+ * with the hostname and {@code -1}
+ * as its arguments to see if the calling code is allowed to know
+ * the hostname for this IP address, i.e., to connect to the host.
+ * If the operation is not allowed, it will return
+ * the textual representation of the IP address.
+ *
+ * @return the host name for this IP address, or if the operation
+ * is not allowed by the security check, the textual
+ * representation of the IP address.
+ *
+ * @param check make security check if true
+ *
+ * @see SecurityManager#checkConnect
+ */
+ private static String getHostFromNameService(InetAddress addr, boolean check) {
+ String host = null;
+ try {
+ // first lookup the hostname
+ host = nameService.getHostByAddr(addr.getAddress());
+
+ /* check to see if calling code is allowed to know
+ * the hostname for this IP address, ie, connect to the host
+ */
+ if (check) {
+ SecurityManager sec = System.getSecurityManager();
+ if (sec != null) {
+ sec.checkConnect(host, -1);
+ }
+ }
+
+ /* now get all the IP addresses for this hostname,
+ * and make sure one of them matches the original IP
+ * address. We do this to try and prevent spoofing.
+ */
+
+ InetAddress[] arr = InetAddress.getAllByName0(host, check);
+ boolean ok = false;
+
+ if(arr != null) {
+ for(int i = 0; !ok && i < arr.length; i++) {
+ ok = addr.equals(arr[i]);
+ }
+ }
+
+ //XXX: if it looks a spoof just return the address?
+ if (!ok) {
+ host = addr.getHostAddress();
+ return host;
+ }
+ } catch (SecurityException e) {
+ host = addr.getHostAddress();
+ } catch (UnknownHostException e) {
+ host = addr.getHostAddress();
+ // let next provider resolve the hostname
+ }
+ return host;
+ }
+
+ /**
+ * Returns the raw IP address of this {@code InetAddress}
+ * object. The result is in network byte order: the highest order
+ * byte of the address is in {@code getAddress()[0]}.
+ *
+ * @return the raw IP address of this object.
+ */
+ public byte[] getAddress() {
+ return null;
+ }
+
+ /**
+ * Returns the IP address string in textual presentation.
+ *
+ * @return the raw IP address in a string format.
+ * @since 1.0.2
+ */
+ public String getHostAddress() {
+ return null;
+ }
+
+ /**
+ * Returns a hashcode for this IP address.
+ *
+ * @return a hash code value for this IP address.
+ */
+ public int hashCode() {
+ return -1;
+ }
+
+ /**
+ * Compares this object against the specified object.
+ * The result is {@code true} if and only if the argument is
+ * not {@code null} and it represents the same IP address as
+ * this object.
+ * <p>
+ * Two instances of {@code InetAddress} represent the same IP
+ * address if the length of the byte arrays returned by
+ * {@code getAddress} is the same for both, and each of the
+ * array components is the same for the byte arrays.
+ *
+ * @param obj the object to compare against.
+ * @return {@code true} if the objects are the same;
+ * {@code false} otherwise.
+ * @see java.net.InetAddress#getAddress()
+ */
+ public boolean equals(Object obj) {
+ return false;
+ }
+
+ /**
+ * Converts this IP address to a {@code String}. The
+ * string returned is of the form: hostname / literal IP
+ * address.
+ *
+ * If the host name is unresolved, no reverse name service lookup
+ * is performed. The hostname part will be represented by an empty string.
+ *
+ * @return a string representation of this IP address.
+ */
+ public String toString() {
+ String hostName = holder().getHostName();
+ return Objects.toString(hostName, "")
+ + "/" + getHostAddress();
+ }
+
+ // mapping from host name to Addresses - either NameServiceAddresses (while
+ // still being looked-up by NameService(s)) or CachedAddresses when cached
+ private static final ConcurrentMap<String, Addresses> cache =
+ new ConcurrentHashMap<>();
+
+ // CachedAddresses that have to expire are kept ordered in this NavigableSet
+ // which is scanned on each access
+ private static final NavigableSet<CachedAddresses> expirySet =
+ new ConcurrentSkipListSet<>();
+
+ // common interface
+ private interface Addresses {
+ InetAddress[] get() throws UnknownHostException;
+ }
+
+ // a holder for cached addresses with required metadata
+ private static final class CachedAddresses implements Addresses, Comparable<CachedAddresses> {
+ private static final AtomicLong seq = new AtomicLong();
+ final String host;
+ final InetAddress[] inetAddresses;
+ final long expiryTime; // time of expiry (in terms of System.nanoTime())
+ final long id = seq.incrementAndGet(); // each instance is unique
+
+ CachedAddresses(String host, InetAddress[] inetAddresses, long expiryTime) {
+ this.host = host;
+ this.inetAddresses = inetAddresses;
+ this.expiryTime = expiryTime;
+ }
+
+ @Override
+ public InetAddress[] get() throws UnknownHostException {
+ if (inetAddresses == null) {
+ throw new UnknownHostException(host);
+ }
+ return inetAddresses;
+ }
+
+ @Override
+ public int compareTo(CachedAddresses other) {
+ // natural order is expiry time -
+ // compare difference of expiry times rather than
+ // expiry times directly, to avoid possible overflow.
+ // (see System.nanoTime() recommendations...)
+ long diff = this.expiryTime - other.expiryTime;
+ if (diff < 0L) return -1;
+ if (diff > 0L) return 1;
+ // ties are broken using unique id
+ return Long.compare(this.id, other.id);
+ }
+ }
+
+ // a name service lookup based Addresses implementation which replaces itself
+ // in cache when the result is obtained
+ private static final class NameServiceAddresses implements Addresses {
+ private final String host;
+ private final InetAddress reqAddr;
+
+ NameServiceAddresses(String host, InetAddress reqAddr) {
+ this.host = host;
+ this.reqAddr = reqAddr;
+ }
+
+ @Override
+ public InetAddress[] get() throws UnknownHostException {
+ Addresses addresses;
+ // only one thread is doing lookup to name service
+ // for particular host at any time.
+ synchronized (this) {
+ // re-check that we are still us + re-install us if slot empty
+ addresses = cache.putIfAbsent(host, this);
+ if (addresses == null) {
+ // this can happen when we were replaced by CachedAddresses in
+ // some other thread, then CachedAddresses expired and were
+ // removed from cache while we were waiting for lock...
+ addresses = this;
+ }
+ // still us ?
+ if (addresses == this) {
+ // lookup name services
+ InetAddress[] inetAddresses;
+ UnknownHostException ex;
+ int cachePolicy;
+ try {
+ inetAddresses = getAddressesFromNameService(host, reqAddr);
+ ex = null;
+ cachePolicy = InetAddressCachePolicy.get();
+ } catch (UnknownHostException uhe) {
+ inetAddresses = null;
+ ex = uhe;
+ cachePolicy = InetAddressCachePolicy.getNegative();
+ }
+ // remove or replace us with cached addresses according to cachePolicy
+ if (cachePolicy == InetAddressCachePolicy.NEVER) {
+ cache.remove(host, this);
+ } else {
+ CachedAddresses cachedAddresses = new CachedAddresses(
+ host,
+ inetAddresses,
+ cachePolicy == InetAddressCachePolicy.FOREVER
+ ? 0L
+ // cachePolicy is in [s] - we need [ns]
+ : System.nanoTime() + 1000_000_000L * cachePolicy
+ );
+ if (cache.replace(host, this, cachedAddresses) &&
+ cachePolicy != InetAddressCachePolicy.FOREVER) {
+ // schedule expiry
+ expirySet.add(cachedAddresses);
+ }
+ }
+ if (inetAddresses == null) {
+ throw ex == null ? new UnknownHostException(host) : ex;
+ }
+ return inetAddresses;
+ }
+ // else addresses != this
+ }
+ // delegate to different addresses when we are already replaced
+ // but outside of synchronized block to avoid any chance of dead-locking
+ return addresses.get();
+ }
+ }
+
+ /**
+ * NameService provides host and address lookup service
+ *
+ * @since 9
+ */
+ private interface NameService {
+
+ /**
+ * Lookup a host mapping by name. Retrieve the IP addresses
+ * associated with a host
+ *
+ * @param host the specified hostname
+ * @return array of IP addresses for the requested host
+ * @throws UnknownHostException
+ * if no IP address for the {@code host} could be found
+ */
+ InetAddress[] lookupAllHostAddr(String host)
+ throws UnknownHostException;
+
+ /**
+ * Lookup the host corresponding to the IP address provided
+ *
+ * @param addr byte array representing an IP address
+ * @return {@code String} representing the host name mapping
+ * @throws UnknownHostException
+ * if no host found for the specified IP address
+ */
+ String getHostByAddr(byte[] addr) throws UnknownHostException;
+
+ }
+
+ /**
+ * The default NameService implementation, which delegates to the underlying
+ * OS network libraries to resolve host address mappings.
+ *
+ * @since 9
+ */
+ private static final class PlatformNameService implements NameService {
+
+ public InetAddress[] lookupAllHostAddr(String host)
+ throws UnknownHostException
+ {
+ return impl.lookupAllHostAddr(host);
+ }
+
+ public String getHostByAddr(byte[] addr)
+ throws UnknownHostException
+ {
+ return impl.getHostByAddr(addr);
+ }
+ }
+
+ /**
+ * The HostsFileNameService provides host address mapping
+ * by reading the entries in a hosts file, which is specified by
+ * {@code jdk.net.hosts.file} system property
+ *
+ * <p>The file format is that which corresponds with the /etc/hosts file
+ * IP Address host alias list.
+ *
+ * <p>When the file lookup is enabled it replaces the default NameService
+ * implementation
+ *
+ * @since 9
+ */
+ private static final class HostsFileNameService implements NameService {
+
+ private final String hostsFile;
+
+ public HostsFileNameService (String hostsFileName) {
+ this.hostsFile = hostsFileName;
+ }
+
+ private String addrToString(byte addr[]) {
+ String stringifiedAddress = null;
+
+ if (addr.length == Inet4Address.INADDRSZ) {
+ stringifiedAddress = Inet4Address.numericToTextFormat(addr);
+ } else { // treat as an IPV6 jobby
+ byte[] newAddr
+ = IPAddressUtil.convertFromIPv4MappedAddress(addr);
+ if (newAddr != null) {
+ stringifiedAddress = Inet4Address.numericToTextFormat(addr);
+ } else {
+ stringifiedAddress = Inet6Address.numericToTextFormat(addr);
+ }
+ }
+ return stringifiedAddress;
+ }
+
+ /**
+ * Lookup the host name corresponding to the IP address provided.
+ * Search the configured host file a host name corresponding to
+ * the specified IP address.
+ *
+ * @param addr byte array representing an IP address
+ * @return {@code String} representing the host name mapping
+ * @throws UnknownHostException
+ * if no host found for the specified IP address
+ */
+ @Override
+ public String getHostByAddr(byte[] addr) throws UnknownHostException {
+ String hostEntry;
+ String host = null;
+
+ String addrString = addrToString(addr);
+ try (Scanner hostsFileScanner = new Scanner(new File(hostsFile), "UTF-8")) {
+ while (hostsFileScanner.hasNextLine()) {
+ hostEntry = hostsFileScanner.nextLine();
+ if (!hostEntry.startsWith("#")) {
+ hostEntry = removeComments(hostEntry);
+ if (hostEntry.contains(addrString)) {
+ host = extractHost(hostEntry, addrString);
+ if (host != null) {
+ break;
+ }
+ }
+ }
+ }
+ } catch (FileNotFoundException e) {
+ throw new UnknownHostException("Unable to resolve address "
+ + addrString + " as hosts file " + hostsFile
+ + " not found ");
+ }
+
+ if ((host == null) || (host.equals("")) || (host.equals(" "))) {
+ throw new UnknownHostException("Requested address "
+ + addrString
+ + " resolves to an invalid entry in hosts file "
+ + hostsFile);
+ }
+ return host;
+ }
+
+ /**
+ * <p>Lookup a host mapping by name. Retrieve the IP addresses
+ * associated with a host.
+ *
+ * <p>Search the configured hosts file for the addresses assocaited with
+ * with the specified host name.
+ *
+ * @param host the specified hostname
+ * @return array of IP addresses for the requested host
+ * @throws UnknownHostException
+ * if no IP address for the {@code host} could be found
+ */
+ public InetAddress[] lookupAllHostAddr(String host)
+ throws UnknownHostException {
+ String hostEntry;
+ String addrStr = null;
+ InetAddress[] res = null;
+ byte addr[] = new byte[4];
+ ArrayList<InetAddress> inetAddresses = null;
+
+ // lookup the file and create a list InetAddress for the specfied host
+ try (Scanner hostsFileScanner = new Scanner(new File(hostsFile), "UTF-8")) {
+ while (hostsFileScanner.hasNextLine()) {
+ hostEntry = hostsFileScanner.nextLine();
+ if (!hostEntry.startsWith("#")) {
+ hostEntry = removeComments(hostEntry);
+ if (hostEntry.contains(host)) {
+ addrStr = extractHostAddr(hostEntry, host);
+ if ((addrStr != null) && (!addrStr.equals(""))) {
+ addr = createAddressByteArray(addrStr);
+ if (inetAddresses == null) {
+ inetAddresses = new ArrayList<>(1);
+ }
+ if (addr != null) {
+ inetAddresses.add(InetAddress.getByAddress(host, addr));
+ }
+ }
+ }
+ }
+ }
+ } catch (FileNotFoundException e) {
+ throw new UnknownHostException("Unable to resolve host " + host
+ + " as hosts file " + hostsFile + " not found ");
+ }
+
+ if (inetAddresses != null) {
+ res = inetAddresses.toArray(new InetAddress[inetAddresses.size()]);
+ } else {
+ throw new UnknownHostException("Unable to resolve host " + host
+ + " in hosts file " + hostsFile);
+ }
+ return res;
+ }
+
+ private String removeComments(String hostsEntry) {
+ String filteredEntry = hostsEntry;
+ int hashIndex;
+
+ if ((hashIndex = hostsEntry.indexOf("#")) != -1) {
+ filteredEntry = hostsEntry.substring(0, hashIndex);
+ }
+ return filteredEntry;
+ }
+
+ private byte [] createAddressByteArray(String addrStr) {
+ byte[] addrArray;
+ // check if IPV4 address - most likely
+ addrArray = IPAddressUtil.textToNumericFormatV4(addrStr);
+ if (addrArray == null) {
+ addrArray = IPAddressUtil.textToNumericFormatV6(addrStr);
+ }
+ return addrArray;
+ }
+
+ /** host to ip address mapping */
+ private String extractHostAddr(String hostEntry, String host) {
+ String[] mapping = hostEntry.split("\\s+");
+ String hostAddr = null;
+
+ if (mapping.length >= 2) {
+ // look at the host aliases
+ for (int i = 1; i < mapping.length; i++) {
+ if (mapping[i].equalsIgnoreCase(host)) {
+ hostAddr = mapping[0];
+ }
+ }
+ }
+ return hostAddr;
+ }
+
+ /**
+ * IP Address to host mapping
+ * use first host alias in list
+ */
+ private String extractHost(String hostEntry, String addrString) {
+ String[] mapping = hostEntry.split("\\s+");
+ String host = null;
+
+ if (mapping.length >= 2) {
+ if (mapping[0].equalsIgnoreCase(addrString)) {
+ host = mapping[1];
+ }
+ }
+ return host;
+ }
+ }
+
+ static final InetAddressImpl impl;
+
+ static {
+ // create the impl
+ impl = InetAddressImplFactory.create();
+
+ // create name service
+ nameService = createNameService();
+ }
+
+ /**
+ * Create an instance of the NameService interface based on
+ * the setting of the {@codejdk.net.hosts.file} system property.
+ *
+ * <p>The default NameService is the PlatformNameService, which typically
+ * delegates name and address resolution calls to the underlying
+ * OS network libraries.
+ *
+ * <p> A HostsFileNameService is created if the {@code jdk.net.hosts.file}
+ * system property is set. If the specified file doesn't exist, the name or
+ * address lookup will result in an UnknownHostException. Thus, non existent
+ * hosts file is handled as if the file is empty.
+ *
+ * @return a NameService
+ */
+ private static NameService createNameService() {
+
+ String hostsFileName =
+ GetPropertyAction.privilegedGetProperty("jdk.net.hosts.file");
+ NameService theNameService;
+ if (hostsFileName != null) {
+ theNameService = new HostsFileNameService(hostsFileName);
+ } else {
+ theNameService = new PlatformNameService();
+ }
+ return theNameService;
+ }
+
+ /**
+ * Creates an InetAddress based on the provided host name and IP address.
+ * No name service is checked for the validity of the address.
+ *
+ * <p> The host name can either be a machine name, such as
+ * "{@code java.sun.com}", or a textual representation of its IP
+ * address.
+ * <p> No validity checking is done on the host name either.
+ *
+ * <p> If addr specifies an IPv4 address an instance of Inet4Address
+ * will be returned; otherwise, an instance of Inet6Address
+ * will be returned.
+ *
+ * <p> IPv4 address byte array must be 4 bytes long and IPv6 byte array
+ * must be 16 bytes long
+ *
+ * @param host the specified host
+ * @param addr the raw IP address in network byte order
+ * @return an InetAddress object created from the raw IP address.
+ * @exception UnknownHostException if IP address is of illegal length
+ * @since 1.4
+ */
+ public static InetAddress getByAddress(String host, byte[] addr)
+ throws UnknownHostException {
+ if (host != null && host.length() > 0 && host.charAt(0) == '[') {
+ if (host.charAt(host.length()-1) == ']') {
+ host = host.substring(1, host.length() -1);
+ }
+ }
+ if (addr != null) {
+ if (addr.length == Inet4Address.INADDRSZ) {
+ return new Inet4Address(host, addr);
+ } else if (addr.length == Inet6Address.INADDRSZ) {
+ byte[] newAddr
+ = IPAddressUtil.convertFromIPv4MappedAddress(addr);
+ if (newAddr != null) {
+ return new Inet4Address(host, newAddr);
+ } else {
+ return new Inet6Address(host, addr);
+ }
+ }
+ }
+ throw new UnknownHostException("addr is of illegal length");
+ }
+
+
+ /**
+ * Determines the IP address of a host, given the host's name.
+ *
+ * <p> The host name can either be a machine name, such as
+ * "{@code java.sun.com}", or a textual representation of its
+ * IP address. If a literal IP address is supplied, only the
+ * validity of the address format is checked.
+ *
+ * <p> For {@code host} specified in literal IPv6 address,
+ * either the form defined in RFC 2732 or the literal IPv6 address
+ * format defined in RFC 2373 is accepted. IPv6 scoped addresses are also
+ * supported. See <a href="Inet6Address.html#scoped">here</a> for a description of IPv6
+ * scoped addresses.
+ *
+ * <p> If the host is {@code null} then an {@code InetAddress}
+ * representing an address of the loopback interface is returned.
+ * See <a href="http://www.ietf.org/rfc/rfc3330.txt">RFC 3330</a>
+ * section 2 and <a href="http://www.ietf.org/rfc/rfc2373.txt">RFC 2373</a>
+ * section 2.5.3. </p>
+ *
+ * @param host the specified host, or {@code null}.
+ * @return an IP address for the given host name.
+ * @exception UnknownHostException if no IP address for the
+ * {@code host} could be found, or if a scope_id was specified
+ * for a global IPv6 address.
+ * @exception SecurityException if a security manager exists
+ * and its checkConnect method doesn't allow the operation
+ */
+ public static InetAddress getByName(String host)
+ throws UnknownHostException {
+ return InetAddress.getAllByName(host)[0];
+ }
+
+ // called from deployment cache manager
+ private static InetAddress getByName(String host, InetAddress reqAddr)
+ throws UnknownHostException {
+ return InetAddress.getAllByName(host, reqAddr)[0];
+ }
+
+ /**
+ * Given the name of a host, returns an array of its IP addresses,
+ * based on the configured name service on the system.
+ *
+ * <p> The host name can either be a machine name, such as
+ * "{@code java.sun.com}", or a textual representation of its IP
+ * address. If a literal IP address is supplied, only the
+ * validity of the address format is checked.
+ *
+ * <p> For {@code host} specified in <i>literal IPv6 address</i>,
+ * either the form defined in RFC 2732 or the literal IPv6 address
+ * format defined in RFC 2373 is accepted. A literal IPv6 address may
+ * also be qualified by appending a scoped zone identifier or scope_id.
+ * The syntax and usage of scope_ids is described
+ * <a href="Inet6Address.html#scoped">here</a>.
+ * <p> If the host is {@code null} then an {@code InetAddress}
+ * representing an address of the loopback interface is returned.
+ * See <a href="http://www.ietf.org/rfc/rfc3330.txt">RFC 3330</a>
+ * section 2 and <a href="http://www.ietf.org/rfc/rfc2373.txt">RFC 2373</a>
+ * section 2.5.3. </p>
+ *
+ * <p> If there is a security manager and {@code host} is not
+ * null and {@code host.length() } is not equal to zero, the
+ * security manager's
+ * {@code checkConnect} method is called
+ * with the hostname and {@code -1}
+ * as its arguments to see if the operation is allowed.
+ *
+ * @param host the name of the host, or {@code null}.
+ * @return an array of all the IP addresses for a given host name.
+ *
+ * @exception UnknownHostException if no IP address for the
+ * {@code host} could be found, or if a scope_id was specified
+ * for a global IPv6 address.
+ * @exception SecurityException if a security manager exists and its
+ * {@code checkConnect} method doesn't allow the operation.
+ *
+ * @see SecurityManager#checkConnect
+ */
+ public static InetAddress[] getAllByName(String host)
+ throws UnknownHostException {
+ return getAllByName(host, null);
+ }
+
+ private static InetAddress[] getAllByName(String host, InetAddress reqAddr)
+ throws UnknownHostException {
+
+ if (host == null || host.length() == 0) {
+ InetAddress[] ret = new InetAddress[1];
+ ret[0] = impl.loopbackAddress();
+ return ret;
+ }
+
+ boolean ipv6Expected = false;
+ if (host.charAt(0) == '[') {
+ // This is supposed to be an IPv6 literal
+ if (host.length() > 2 && host.charAt(host.length()-1) == ']') {
+ host = host.substring(1, host.length() -1);
+ ipv6Expected = true;
+ } else {
+ // This was supposed to be a IPv6 address, but it's not!
+ throw new UnknownHostException(host + ": invalid IPv6 address");
+ }
+ }
+
+ // if host is an IP address, we won't do further lookup
+ if (Character.digit(host.charAt(0), 16) != -1
+ || (host.charAt(0) == ':')) {
+ byte[] addr = null;
+ int numericZone = -1;
+ String ifname = null;
+ // see if it is IPv4 address
+ addr = IPAddressUtil.textToNumericFormatV4(host);
+ if (addr == null) {
+ // This is supposed to be an IPv6 literal
+ // Check if a numeric or string zone id is present
+ int pos;
+ if ((pos=host.indexOf ('%')) != -1) {
+ numericZone = checkNumericZone (host);
+ if (numericZone == -1) { /* remainder of string must be an ifname */
+ ifname = host.substring (pos+1);
+ }
+ }
+ if ((addr = IPAddressUtil.textToNumericFormatV6(host)) == null && host.contains(":")) {
+ throw new UnknownHostException(host + ": invalid IPv6 address");
+ }
+ } else if (ipv6Expected) {
+ // Means an IPv4 litteral between brackets!
+ throw new UnknownHostException("["+host+"]");
+ }
+ InetAddress[] ret = new InetAddress[1];
+ if(addr != null) {
+ if (addr.length == Inet4Address.INADDRSZ) {
+ ret[0] = new Inet4Address(null, addr);
+ } else {
+ if (ifname != null) {
+ ret[0] = new Inet6Address(null, addr, ifname);
+ } else {
+ ret[0] = new Inet6Address(null, addr, numericZone);
+ }
+ }
+ return ret;
+ }
+ } else if (ipv6Expected) {
+ // We were expecting an IPv6 Litteral, but got something else
+ throw new UnknownHostException("["+host+"]");
+ }
+ return getAllByName0(host, reqAddr, true, true);
+ }
+
+ /**
+ * Returns the loopback address.
+ * <p>
+ * The InetAddress returned will represent the IPv4
+ * loopback address, 127.0.0.1, or the IPv6 loopback
+ * address, ::1. The IPv4 loopback address returned
+ * is only one of many in the form 127.*.*.*
+ *
+ * @return the InetAddress loopback instance.
+ * @since 1.7
+ */
+ public static InetAddress getLoopbackAddress() {
+ return impl.loopbackAddress();
+ }
+
+
+ /**
+ * check if the literal address string has %nn appended
+ * returns -1 if not, or the numeric value otherwise.
+ *
+ * %nn may also be a string that represents the displayName of
+ * a currently available NetworkInterface.
+ */
+ private static int checkNumericZone (String s) throws UnknownHostException {
+ int percent = s.indexOf ('%');
+ int slen = s.length();
+ int digit, zone=0;
+ if (percent == -1) {
+ return -1;
+ }
+ for (int i=percent+1; i<slen; i++) {
+ char c = s.charAt(i);
+ if (c == ']') {
+ if (i == percent+1) {
+ /* empty per-cent field */
+ return -1;
+ }
+ break;
+ }
+ if ((digit = Character.digit (c, 10)) < 0) {
+ return -1;
+ }
+ zone = (zone * 10) + digit;
+ }
+ return zone;
+ }
+
+ private static InetAddress[] getAllByName0 (String host)
+ throws UnknownHostException
+ {
+ return getAllByName0(host, true);
+ }
+
+ /**
+ * package private so SocketPermission can call it
+ */
+ static InetAddress[] getAllByName0 (String host, boolean check)
+ throws UnknownHostException {
+ return getAllByName0 (host, null, check, true);
+ }
+
+ /**
+ * Designated lookup method.
+ *
+ * @param host host name to look up
+ * @param reqAddr requested address to be the 1st in returned array
+ * @param check perform security check
+ * @param useCache use cached value if not expired else always
+ * perform name service lookup (and cache the result)
+ * @return array of InetAddress(es)
+ * @throws UnknownHostException if host name is not found
+ */
+ private static InetAddress[] getAllByName0(String host,
+ InetAddress reqAddr,
+ boolean check,
+ boolean useCache)
+ throws UnknownHostException {
+
+ /* If it gets here it is presumed to be a hostname */
+
+ /* make sure the connection to the host is allowed, before we
+ * give out a hostname
+ */
+ if (check) {
+ SecurityManager security = System.getSecurityManager();
+ if (security != null) {
+ security.checkConnect(host, -1);
+ }
+ }
+
+ // remove expired addresses from cache - expirySet keeps them ordered
+ // by expiry time so we only need to iterate the prefix of the NavigableSet...
+ long now = System.nanoTime();
+ for (CachedAddresses caddrs : expirySet) {
+ // compare difference of time instants rather than
+ // time instants directly, to avoid possible overflow.
+ // (see System.nanoTime() recommendations...)
+ if ((caddrs.expiryTime - now) < 0L) {
+ // ConcurrentSkipListSet uses weakly consistent iterator,
+ // so removing while iterating is OK...
+ if (expirySet.remove(caddrs)) {
+ // ... remove from cache
+ cache.remove(caddrs.host, caddrs);
+ }
+ } else {
+ // we encountered 1st element that expires in future
+ break;
+ }
+ }
+
+ // look-up or remove from cache
+ Addresses addrs;
+ if (useCache) {
+ addrs = cache.get(host);
+ } else {
+ addrs = cache.remove(host);
+ if (addrs != null) {
+ if (addrs instanceof CachedAddresses) {
+ // try removing from expirySet too if CachedAddresses
+ expirySet.remove(addrs);
+ }
+ addrs = null;
+ }
+ }
+
+ if (addrs == null) {
+ // create a NameServiceAddresses instance which will look up
+ // the name service and install it within cache...
+ Addresses oldAddrs = cache.putIfAbsent(
+ host,
+ addrs = new NameServiceAddresses(host, reqAddr)
+ );
+ if (oldAddrs != null) { // lost putIfAbsent race
+ addrs = oldAddrs;
+ }
+ }
+
+ // ask Addresses to get an array of InetAddress(es) and clone it
+ return addrs.get().clone();
+ }
+
+ static InetAddress[] getAddressesFromNameService(String host, InetAddress reqAddr)
+ throws UnknownHostException
+ {
+ InetAddress[] addresses = null;
+ UnknownHostException ex = null;
+
+ try {
+ addresses = nameService.lookupAllHostAddr(host);
+ } catch (UnknownHostException uhe) {
+ if (host.equalsIgnoreCase("localhost")) {
+ addresses = new InetAddress[] { impl.loopbackAddress() };
+ }
+ else {
+ ex = uhe;
+ }
+ }
+
+ if (addresses == null) {
+ throw ex == null ? new UnknownHostException(host) : ex;
+ }
+
+ // More to do?
+ if (reqAddr != null && addresses.length > 1 && !addresses[0].equals(reqAddr)) {
+ // Find it?
+ int i = 1;
+ for (; i < addresses.length; i++) {
+ if (addresses[i].equals(reqAddr)) {
+ break;
+ }
+ }
+ // Rotate
+ if (i < addresses.length) {
+ InetAddress tmp, tmp2 = reqAddr;
+ for (int j = 0; j < i; j++) {
+ tmp = addresses[j];
+ addresses[j] = tmp2;
+ tmp2 = tmp;
+ }
+ addresses[i] = tmp2;
+ }
+ }
+
+ return addresses;
+ }
+
+ /**
+ * Returns an {@code InetAddress} object given the raw IP address .
+ * The argument is in network byte order: the highest order
+ * byte of the address is in {@code getAddress()[0]}.
+ *
+ * <p> This method doesn't block, i.e. no reverse name service lookup
+ * is performed.
+ *
+ * <p> IPv4 address byte array must be 4 bytes long and IPv6 byte array
+ * must be 16 bytes long
+ *
+ * @param addr the raw IP address in network byte order
+ * @return an InetAddress object created from the raw IP address.
+ * @exception UnknownHostException if IP address is of illegal length
+ * @since 1.4
+ */
+ public static InetAddress getByAddress(byte[] addr)
+ throws UnknownHostException {
+ return getByAddress(null, addr);
+ }
+
+ private static final class CachedLocalHost {
+ final String host;
+ final InetAddress addr;
+ final long expiryTime = System.nanoTime() + 5000_000_000L; // now + 5s;
+
+ CachedLocalHost(String host, InetAddress addr) {
+ this.host = host;
+ this.addr = addr;
+ }
+ }
+
+ private static volatile CachedLocalHost cachedLocalHost;
+
+ /**
+ * Returns the address of the local host. This is achieved by retrieving
+ * the name of the host from the system, then resolving that name into
+ * an {@code InetAddress}.
+ *
+ * <P>Note: The resolved address may be cached for a short period of time.
+ * </P>
+ *
+ * <p>If there is a security manager, its
+ * {@code checkConnect} method is called
+ * with the local host name and {@code -1}
+ * as its arguments to see if the operation is allowed.
+ * If the operation is not allowed, an InetAddress representing
+ * the loopback address is returned.
+ *
+ * @return the address of the local host.
+ *
+ * @exception UnknownHostException if the local host name could not
+ * be resolved into an address.
+ *
+ * @see SecurityManager#checkConnect
+ * @see java.net.InetAddress#getByName(java.lang.String)
+ */
+ public static InetAddress getLocalHost() throws UnknownHostException {
+
+ SecurityManager security = System.getSecurityManager();
+ try {
+ // is cached data still valid?
+ CachedLocalHost clh = cachedLocalHost;
+ if (clh != null && (clh.expiryTime - System.nanoTime()) >= 0L) {
+ if (security != null) {
+ security.checkConnect(clh.host, -1);
+ }
+ return clh.addr;
+ }
+
+ String local = impl.getLocalHostName();
+
+ if (security != null) {
+ security.checkConnect(local, -1);
+ }
+
+ InetAddress localAddr;
+ if (local.equals("localhost")) {
+ // shortcut for "localhost" host name
+ localAddr = impl.loopbackAddress();
+ } else {
+ // call getAllByName0 without security checks and
+ // without using cached data
+ try {
+ localAddr = getAllByName0(local, null, false, false)[0];
+ } catch (UnknownHostException uhe) {
+ // Rethrow with a more informative error message.
+ UnknownHostException uhe2 =
+ new UnknownHostException(local + ": " +
+ uhe.getMessage());
+ uhe2.initCause(uhe);
+ throw uhe2;
+ }
+ }
+ cachedLocalHost = new CachedLocalHost(local, localAddr);
+ return localAddr;
+ } catch (java.lang.SecurityException e) {
+ return impl.loopbackAddress();
+ }
+ }
+
+ /**
+ * Perform class load-time initializations.
+ */
+ private static native void init();
+
+
+ /*
+ * Returns the InetAddress representing anyLocalAddress
+ * (typically 0.0.0.0 or ::0)
+ */
+ static InetAddress anyLocalAddress() {
+ return impl.anyLocalAddress();
+ }
+
+ /*
+ * Load and instantiate an underlying impl class
+ */
+ static InetAddressImpl loadImpl(String implName) {
+ Object impl = null;
+
+ /*
+ * Property "impl.prefix" will be prepended to the classname
+ * of the implementation object we instantiate, to which we
+ * delegate the real work (like native methods). This
+ * property can vary across implementations of the java.
+ * classes. The default is an empty String "".
+ */
+ String prefix = GetPropertyAction.privilegedGetProperty("impl.prefix", "");
+ try {
+ @SuppressWarnings("deprecation")
+ Object tmp = Class.forName("java.net." + prefix + implName).newInstance();
+ impl = tmp;
+ } catch (ClassNotFoundException e) {
+ System.err.println("Class not found: java.net." + prefix +
+ implName + ":\ncheck impl.prefix property " +
+ "in your properties file.");
+ } catch (InstantiationException e) {
+ System.err.println("Could not instantiate: java.net." + prefix +
+ implName + ":\ncheck impl.prefix property " +
+ "in your properties file.");
+ } catch (IllegalAccessException e) {
+ System.err.println("Cannot access class: java.net." + prefix +
+ implName + ":\ncheck impl.prefix property " +
+ "in your properties file.");
+ }
+
+ if (impl == null) {
+ try {
+ @SuppressWarnings("deprecation")
+ Object tmp = Class.forName(implName).newInstance();
+ impl = tmp;
+ } catch (Exception e) {
+ throw new Error("System property impl.prefix incorrect");
+ }
+ }
+
+ return (InetAddressImpl) impl;
+ }
+
+ private void readObjectNoData (ObjectInputStream s) throws
+ IOException, ClassNotFoundException {
+ if (getClass().getClassLoader() != null) {
+ throw new SecurityException ("invalid address type");
+ }
+ }
+
+ private static final jdk.internal.misc.Unsafe UNSAFE
+ = jdk.internal.misc.Unsafe.getUnsafe();
+ private static final long FIELDS_OFFSET
+ = UNSAFE.objectFieldOffset(InetAddress.class, "holder");
+
+ private void readObject (ObjectInputStream s) throws
+ IOException, ClassNotFoundException {
+ if (getClass().getClassLoader() != null) {
+ throw new SecurityException ("invalid address type");
+ }
+ GetField gf = s.readFields();
+ String host = (String)gf.get("hostName", null);
+ int address= gf.get("address", 0);
+ int family= gf.get("family", 0);
+ InetAddressHolder h = new InetAddressHolder(host, address, family);
+ UNSAFE.putObject(this, FIELDS_OFFSET, h);
+ }
+
+ /* needed because the serializable fields no longer exist */
+
+ /**
+ * @serialField hostName String
+ * @serialField address int
+ * @serialField family int
+ */
+ private static final ObjectStreamField[] serialPersistentFields = {
+ new ObjectStreamField("hostName", String.class),
+ new ObjectStreamField("address", int.class),
+ new ObjectStreamField("family", int.class),
+ };
+
+ private void writeObject (ObjectOutputStream s) throws
+ IOException {
+ if (getClass().getClassLoader() != null) {
+ throw new SecurityException ("invalid address type");
+ }
+ PutField pf = s.putFields();
+ pf.put("hostName", holder().getHostName());
+ pf.put("address", holder().getAddress());
+ pf.put("family", holder().getFamily());
+ s.writeFields();
+ }
+}
+
+/*
+ * Simple factory to create the impl
+ */
+class InetAddressImplFactory {
+
+ static InetAddressImpl create() {
+ return InetAddress.loadImpl(isIPv6Supported() ?
+ "Inet6AddressImpl" : "Inet4AddressImpl");
+ }
+
+ static native boolean isIPv6Supported();
+}