https://source.android.com/ 
/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * Licensed 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 android.net;

import android.annotation.NonNull;
import android.annotation.Nullable;
import android.os.Parcel;
import android.os.Parcelable;
import android.text.TextUtils;

import java.net.Inet4Address;
import java.net.Inet6Address;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Hashtable;
import java.util.List;
import java.util.Objects;


Describes the properties of a network link.
A link represents a connection to a network.
It may have multiple addresses and multiple gateways,
multiple dns servers but only one http proxy and one
network interface.
Note that this is just a holder of data.  Modifying it
does not affect live networks.

/**
 * Describes the properties of a network link.
 *
 * A link represents a connection to a network.
 * It may have multiple addresses and multiple gateways,
 * multiple dns servers but only one http proxy and one
 * network interface.
 *
 * Note that this is just a holder of data.  Modifying it
 * does not affect live networks.
 *
 */
public final class LinkProperties implements Parcelable {
    // The interface described by the network link.
    private String mIfaceName;
    private ArrayList<LinkAddress> mLinkAddresses = new ArrayList<LinkAddress>();
    private ArrayList<InetAddress> mDnses = new ArrayList<InetAddress>();
    private ArrayList<InetAddress> mValidatedPrivateDnses = new ArrayList<InetAddress>();
    private boolean mUsePrivateDns;
    private String mPrivateDnsServerName;
    private String mDomains;
    private ArrayList<RouteInfo> mRoutes = new ArrayList<RouteInfo>();
    private ProxyInfo mHttpProxy;
    private int mMtu;
    // in the format "rmem_min,rmem_def,rmem_max,wmem_min,wmem_def,wmem_max"
    private String mTcpBufferSizes;

    private static final int MIN_MTU    = 68;
    private static final int MIN_MTU_V6 = 1280;
    private static final int MAX_MTU    = 10000;

    // Stores the properties of links that are "stacked" above this link.
    // Indexed by interface name to allow modification and to prevent duplicates being added.
    private Hashtable<String, LinkProperties> mStackedLinks =
        new Hashtable<String, LinkProperties>();

    
@hide
/**
     * @hide
     */
    public static class CompareResult<T> {
        public final List<T> removed = new ArrayList<T>();
        public final List<T> added = new ArrayList<T>();

        public CompareResult() {}

        public CompareResult(Collection<T> oldItems, Collection<T> newItems) {
            if (oldItems != null) {
                removed.addAll(oldItems);
            }
            if (newItems != null) {
                for (T newItem : newItems) {
                    if (!removed.remove(newItem)) {
                        added.add(newItem);
                    }
                }
            }
        }

        @Override
        public String toString() {
            String retVal = "removed=[";
            for (T addr : removed) retVal += addr.toString() + ",";
            retVal += "] added=[";
            for (T addr : added) retVal += addr.toString() + ",";
            retVal += "]";
            return retVal;
        }
    }

    
@hide
/**
     * @hide
     */
    public enum ProvisioningChange {
        STILL_NOT_PROVISIONED,
        LOST_PROVISIONING,
        GAINED_PROVISIONING,
        STILL_PROVISIONED,
    }

    
Compare the provisioning states of two LinkProperties instances.

@hide
/**
     * Compare the provisioning states of two LinkProperties instances.
     *
     * @hide
     */
    public static ProvisioningChange compareProvisioning(
            LinkProperties before, LinkProperties after) {
        if (before.isProvisioned() && after.isProvisioned()) {
            // On dualstack networks, DHCPv4 renewals can occasionally fail.
            // When this happens, IPv6-reachable services continue to function
            // normally but IPv4-only services (naturally) fail.
            //
            // When an application using an IPv4-only service reports a bad
            // network condition to the framework, attempts to re-validate
            // the network succeed (since we support IPv6-only networks) and
            // nothing is changed.
            //
            // For users, this is confusing and unexpected behaviour, and is
            // not necessarily easy to diagnose.  Therefore, we treat changing
            // from a dualstack network to an IPv6-only network equivalent to
            // a total loss of provisioning.
            //
            // For one such example of this, see b/18867306.
            //
            // Additionally, losing IPv6 provisioning can result in TCP
            // connections getting stuck until timeouts fire and other
            // baffling failures. Therefore, loss of either IPv4 or IPv6 on a
            // previously dualstack network is deemed a lost of provisioning.
            if ((before.isIPv4Provisioned() && !after.isIPv4Provisioned()) ||
                (before.isIPv6Provisioned() && !after.isIPv6Provisioned())) {
                return ProvisioningChange.LOST_PROVISIONING;
            }
            return ProvisioningChange.STILL_PROVISIONED;
        } else if (before.isProvisioned() && !after.isProvisioned()) {
            return ProvisioningChange.LOST_PROVISIONING;
        } else if (!before.isProvisioned() && after.isProvisioned()) {
            return ProvisioningChange.GAINED_PROVISIONING;
        } else {  // !before.isProvisioned() && !after.isProvisioned()
            return ProvisioningChange.STILL_NOT_PROVISIONED;
        }
    }

    
@hide
/**
     * @hide
     */
    public LinkProperties() {
    }

    
@hide
/**
     * @hide
     */
    public LinkProperties(LinkProperties source) {
        if (source != null) {
            mIfaceName = source.getInterfaceName();
            for (LinkAddress l : source.getLinkAddresses()) mLinkAddresses.add(l);
            for (InetAddress i : source.getDnsServers()) mDnses.add(i);
            for (InetAddress i : source.getValidatedPrivateDnsServers()) {
                mValidatedPrivateDnses.add(i);
            }
            mUsePrivateDns = source.mUsePrivateDns;
            mPrivateDnsServerName = source.mPrivateDnsServerName;
            mDomains = source.getDomains();
            for (RouteInfo r : source.getRoutes()) mRoutes.add(r);
            mHttpProxy = (source.getHttpProxy() == null)  ?
                    null : new ProxyInfo(source.getHttpProxy());
            for (LinkProperties l: source.mStackedLinks.values()) {
                addStackedLink(l);
            }
            setMtu(source.getMtu());
            mTcpBufferSizes = source.mTcpBufferSizes;
        }
    }

    
Sets the interface name for this link. All RouteInfo already set for this will have their interface changed to match this new value. 
Params:
  • iface – The name of the network interface used for this link.
@hide
/**
     * Sets the interface name for this link.  All {@link RouteInfo} already set for this
     * will have their interface changed to match this new value.
     *
     * @param iface The name of the network interface used for this link.
     * @hide
     */
    public void setInterfaceName(String iface) {
        mIfaceName = iface;
        ArrayList<RouteInfo> newRoutes = new ArrayList<RouteInfo>(mRoutes.size());
        for (RouteInfo route : mRoutes) {
            newRoutes.add(routeWithInterface(route));
        }
        mRoutes = newRoutes;
    }

    
Gets the interface name for this link. May be null if not set. 
Returns:The interface name set for this link or null.
/**
     * Gets the interface name for this link.  May be {@code null} if not set.
     *
     * @return The interface name set for this link or {@code null}.
     */
    public @Nullable String getInterfaceName() {
        return mIfaceName;
    }

    
@hide
/**
     * @hide
     */
    public List<String> getAllInterfaceNames() {
        List<String> interfaceNames = new ArrayList<String>(mStackedLinks.size() + 1);
        if (mIfaceName != null) interfaceNames.add(new String(mIfaceName));
        for (LinkProperties stacked: mStackedLinks.values()) {
            interfaceNames.addAll(stacked.getAllInterfaceNames());
        }
        return interfaceNames;
    }

    
Returns all the addresses on this link. We often think of a link having a single address, however, particularly with Ipv6 several addresses are typical. Note that the LinkProperties actually contains LinkAddress objects which also include prefix lengths for each address. This is a simplified utility alternative to getLinkAddresses. 
Returns:An umodifiable List of InetAddress for this link.
@hide
/**
     * Returns all the addresses on this link.  We often think of a link having a single address,
     * however, particularly with Ipv6 several addresses are typical.  Note that the
     * {@code LinkProperties} actually contains {@link LinkAddress} objects which also include
     * prefix lengths for each address.  This is a simplified utility alternative to
     * {@link LinkProperties#getLinkAddresses}.
     *
     * @return An umodifiable {@link List} of {@link InetAddress} for this link.
     * @hide
     */
    public List<InetAddress> getAddresses() {
        List<InetAddress> addresses = new ArrayList<InetAddress>();
        for (LinkAddress linkAddress : mLinkAddresses) {
            addresses.add(linkAddress.getAddress());
        }
        return Collections.unmodifiableList(addresses);
    }

    
Returns all the addresses on this link and all the links stacked above it.

@hide
/**
     * Returns all the addresses on this link and all the links stacked above it.
     * @hide
     */
    public List<InetAddress> getAllAddresses() {
        List<InetAddress> addresses = new ArrayList<InetAddress>();
        for (LinkAddress linkAddress : mLinkAddresses) {
            addresses.add(linkAddress.getAddress());
        }
        for (LinkProperties stacked: mStackedLinks.values()) {
            addresses.addAll(stacked.getAllAddresses());
        }
        return addresses;
    }

    private int findLinkAddressIndex(LinkAddress address) {
        for (int i = 0; i < mLinkAddresses.size(); i++) {
            if (mLinkAddresses.get(i).isSameAddressAs(address)) {
                return i;
            }
        }
        return -1;
    }

    
Adds a LinkAddress to this LinkProperties if a LinkAddress of the same address/prefix does not already exist. If it does exist it is replaced. 
Params:
  • address – The LinkAddress to add.
Returns:true if address was added or updated, false otherwise.
@hide
/**
     * Adds a {@link LinkAddress} to this {@code LinkProperties} if a {@link LinkAddress} of the
     * same address/prefix does not already exist.  If it does exist it is replaced.
     * @param address The {@code LinkAddress} to add.
     * @return true if {@code address} was added or updated, false otherwise.
     * @hide
     */
    public boolean addLinkAddress(LinkAddress address) {
        if (address == null) {
            return false;
        }
        int i = findLinkAddressIndex(address);
        if (i < 0) {
            // Address was not present. Add it.
            mLinkAddresses.add(address);
            return true;
        } else if (mLinkAddresses.get(i).equals(address)) {
            // Address was present and has same properties. Do nothing.
            return false;
        } else {
            // Address was present and has different properties. Update it.
            mLinkAddresses.set(i, address);
            return true;
        }
    }

    
Removes a LinkAddress from this LinkProperties. Specifically, matches and LinkAddress with the same address and prefix. 
Params:
  • toRemove – A LinkAddress specifying the address to remove.
Returns:true if the address was removed, false if it did not exist.
@hide
/**
     * Removes a {@link LinkAddress} from this {@code LinkProperties}.  Specifically, matches
     * and {@link LinkAddress} with the same address and prefix.
     *
     * @param toRemove A {@link LinkAddress} specifying the address to remove.
     * @return true if the address was removed, false if it did not exist.
     * @hide
     */
    public boolean removeLinkAddress(LinkAddress toRemove) {
        int i = findLinkAddressIndex(toRemove);
        if (i >= 0) {
            mLinkAddresses.remove(i);
            return true;
        }
        return false;
    }

    
Returns all the LinkAddress on this link. Typically a link will have one IPv4 address and one or more IPv6 addresses. 
Returns:An unmodifiable List of LinkAddress for this link.
/**
     * Returns all the {@link LinkAddress} on this link.  Typically a link will have
     * one IPv4 address and one or more IPv6 addresses.
     *
     * @return An unmodifiable {@link List} of {@link LinkAddress} for this link.
     */
    public List<LinkAddress> getLinkAddresses() {
        return Collections.unmodifiableList(mLinkAddresses);
    }

    
Returns all the addresses on this link and all the links stacked above it.

@hide
/**
     * Returns all the addresses on this link and all the links stacked above it.
     * @hide
     */
    public List<LinkAddress> getAllLinkAddresses() {
        List<LinkAddress> addresses = new ArrayList<LinkAddress>();
        addresses.addAll(mLinkAddresses);
        for (LinkProperties stacked: mStackedLinks.values()) {
            addresses.addAll(stacked.getAllLinkAddresses());
        }
        return addresses;
    }

    
Replaces the LinkAddress in this LinkProperties with the given Collection of LinkAddress. 
Params:
@hide
/**
     * Replaces the {@link LinkAddress} in this {@code LinkProperties} with
     * the given {@link Collection} of {@link LinkAddress}.
     *
     * @param addresses The {@link Collection} of {@link LinkAddress} to set in this
     *                  object.
     * @hide
     */
    public void setLinkAddresses(Collection<LinkAddress> addresses) {
        mLinkAddresses.clear();
        for (LinkAddress address: addresses) {
            addLinkAddress(address);
        }
    }

    
Adds the given InetAddress to the list of DNS servers, if not present. 
Params:
  • dnsServer – The InetAddress to add to the list of DNS servers.
Returns:true if the DNS server was added, false if it was already present.
@hide
/**
     * Adds the given {@link InetAddress} to the list of DNS servers, if not present.
     *
     * @param dnsServer The {@link InetAddress} to add to the list of DNS servers.
     * @return true if the DNS server was added, false if it was already present.
     * @hide
     */
    public boolean addDnsServer(InetAddress dnsServer) {
        if (dnsServer != null && !mDnses.contains(dnsServer)) {
            mDnses.add(dnsServer);
            return true;
        }
        return false;
    }

    
Removes the given InetAddress from the list of DNS servers. 
Params:
  • dnsServer – The InetAddress to remove from the list of DNS servers.
Returns:true if the DNS server was removed, false if it did not exist.
@hide
/**
     * Removes the given {@link InetAddress} from the list of DNS servers.
     *
     * @param dnsServer The {@link InetAddress} to remove from the list of DNS servers.
     * @return true if the DNS server was removed, false if it did not exist.
     * @hide
     */
    public boolean removeDnsServer(InetAddress dnsServer) {
        if (dnsServer != null) {
            return mDnses.remove(dnsServer);
        }
        return false;
    }

    
Replaces the DNS servers in this LinkProperties with the given Collection of InetAddress objects. 
Params:
  • dnsServers – The Collection of DNS servers to set in this object.
@hide
/**
     * Replaces the DNS servers in this {@code LinkProperties} with
     * the given {@link Collection} of {@link InetAddress} objects.
     *
     * @param dnsServers The {@link Collection} of DNS servers to set in this object.
     * @hide
     */
    public void setDnsServers(Collection<InetAddress> dnsServers) {
        mDnses.clear();
        for (InetAddress dnsServer: dnsServers) {
            addDnsServer(dnsServer);
        }
    }

    
Returns all the InetAddress for DNS servers on this link. 
Returns:An umodifiable List of InetAddress for DNS servers on this link.
/**
     * Returns all the {@link InetAddress} for DNS servers on this link.
     *
     * @return An umodifiable {@link List} of {@link InetAddress} for DNS servers on
     *         this link.
     */
    public List<InetAddress> getDnsServers() {
        return Collections.unmodifiableList(mDnses);
    }

    
Set whether private DNS is currently in use on this network.

Params:
  • usePrivateDns – The private DNS state.
@hide
/**
     * Set whether private DNS is currently in use on this network.
     *
     * @param usePrivateDns The private DNS state.
     * @hide
     */
    public void setUsePrivateDns(boolean usePrivateDns) {
        mUsePrivateDns = usePrivateDns;
    }

    
Returns whether private DNS is currently in use on this network. When private DNS is in use, applications must not send unencrypted DNS queries as doing so could reveal private user information. Furthermore, if private DNS is in use and getPrivateDnsServerName is not null, DNS queries must be sent to the specified DNS server. 
Returns:true if private DNS is in use, false otherwise.
/**
     * Returns whether private DNS is currently in use on this network. When
     * private DNS is in use, applications must not send unencrypted DNS
     * queries as doing so could reveal private user information. Furthermore,
     * if private DNS is in use and {@link #getPrivateDnsServerName} is not
     * {@code null}, DNS queries must be sent to the specified DNS server.
     *
     * @return {@code true} if private DNS is in use, {@code false} otherwise.
     */
    public boolean isPrivateDnsActive() {
        return mUsePrivateDns;
    }

    
Set the name of the private DNS server to which private DNS queries should be sent when in strict mode. This value should be null when private DNS is off or in opportunistic mode. 
Params:
  • privateDnsServerName – The private DNS server name.
@hide
/**
     * Set the name of the private DNS server to which private DNS queries
     * should be sent when in strict mode. This value should be {@code null}
     * when private DNS is off or in opportunistic mode.
     *
     * @param privateDnsServerName The private DNS server name.
     * @hide
     */
    public void setPrivateDnsServerName(@Nullable String privateDnsServerName) {
        mPrivateDnsServerName = privateDnsServerName;
    }

    
Returns the private DNS server name that is in use. If not null, private DNS is in strict mode. In this mode, applications should ensure that all DNS queries are encrypted and sent to this hostname and that queries are only sent if the hostname's certificate is valid. If null and isPrivateDnsActive is true, private DNS is in opportunistic mode, and applications should ensure that DNS queries are encrypted and sent to a DNS server returned by getDnsServers. System DNS will handle each of these cases correctly, but applications implementing their own DNS lookups must make sure to follow these requirements. 
Returns:The private DNS server name.
/**
     * Returns the private DNS server name that is in use. If not {@code null},
     * private DNS is in strict mode. In this mode, applications should ensure
     * that all DNS queries are encrypted and sent to this hostname and that
     * queries are only sent if the hostname's certificate is valid. If
     * {@code null} and {@link #isPrivateDnsActive} is {@code true}, private
     * DNS is in opportunistic mode, and applications should ensure that DNS
     * queries are encrypted and sent to a DNS server returned by
     * {@link #getDnsServers}. System DNS will handle each of these cases
     * correctly, but applications implementing their own DNS lookups must make
     * sure to follow these requirements.
     *
     * @return The private DNS server name.
     */
    public @Nullable String getPrivateDnsServerName() {
        return mPrivateDnsServerName;
    }

    
Adds the given InetAddress to the list of validated private DNS servers, if not present. This is distinct from the server name in that these are actually resolved addresses. 
Params:
  • dnsServer – The InetAddress to add to the list of validated private DNS servers.
Returns:true if the DNS server was added, false if it was already present.
@hide
/**
     * Adds the given {@link InetAddress} to the list of validated private DNS servers,
     * if not present. This is distinct from the server name in that these are actually
     * resolved addresses.
     *
     * @param dnsServer The {@link InetAddress} to add to the list of validated private DNS servers.
     * @return true if the DNS server was added, false if it was already present.
     * @hide
     */
    public boolean addValidatedPrivateDnsServer(InetAddress dnsServer) {
        if (dnsServer != null && !mValidatedPrivateDnses.contains(dnsServer)) {
            mValidatedPrivateDnses.add(dnsServer);
            return true;
        }
        return false;
    }

    
Removes the given InetAddress from the list of validated private DNS servers. 
Params:
  • dnsServer – The InetAddress to remove from the list of validated private DNS servers.
Returns:true if the DNS server was removed, false if it did not exist.
@hide
/**
     * Removes the given {@link InetAddress} from the list of validated private DNS servers.
     *
     * @param dnsServer The {@link InetAddress} to remove from the list of validated private DNS
     *        servers.
     * @return true if the DNS server was removed, false if it did not exist.
     * @hide
     */
    public boolean removeValidatedPrivateDnsServer(InetAddress dnsServer) {
        if (dnsServer != null) {
            return mValidatedPrivateDnses.remove(dnsServer);
        }
        return false;
    }

    
Replaces the validated private DNS servers in this LinkProperties with the given Collection of InetAddress objects. 
Params:
  • dnsServers – The Collection of validated private DNS servers to set in this object.
@hide
/**
     * Replaces the validated private DNS servers in this {@code LinkProperties} with
     * the given {@link Collection} of {@link InetAddress} objects.
     *
     * @param dnsServers The {@link Collection} of validated private DNS servers to set in this
     *        object.
     * @hide
     */
    public void setValidatedPrivateDnsServers(Collection<InetAddress> dnsServers) {
        mValidatedPrivateDnses.clear();
        for (InetAddress dnsServer: dnsServers) {
            addValidatedPrivateDnsServer(dnsServer);
        }
    }

    
Returns all the InetAddress for validated private DNS servers on this link. These are resolved from the private DNS server name. 
Returns:An umodifiable List of InetAddress for validated private DNS servers on this link.
@hide
/**
     * Returns all the {@link InetAddress} for validated private DNS servers on this link.
     * These are resolved from the private DNS server name.
     *
     * @return An umodifiable {@link List} of {@link InetAddress} for validated private
     *         DNS servers on this link.
     * @hide
     */
    public List<InetAddress> getValidatedPrivateDnsServers() {
        return Collections.unmodifiableList(mValidatedPrivateDnses);
    }

    
Sets the DNS domain search path used on this link.

Params:
  • domains – A String listing in priority order the comma separated domains to search when resolving host names on this link.
@hide
/**
     * Sets the DNS domain search path used on this link.
     *
     * @param domains A {@link String} listing in priority order the comma separated
     *                domains to search when resolving host names on this link.
     * @hide
     */
    public void setDomains(String domains) {
        mDomains = domains;
    }

    
Get the DNS domains search path set for this link.

Returns:A String containing the comma separated domains to search when resolving host names on this link.
/**
     * Get the DNS domains search path set for this link.
     *
     * @return A {@link String} containing the comma separated domains to search when resolving
     *         host names on this link.
     */
    public String getDomains() {
        return mDomains;
    }

    
Sets the Maximum Transmission Unit size to use on this link.  This should not be used
unless the system default (1500) is incorrect.  Values less than 68 or greater than
10000 will be ignored.

Params:
  • mtu – The MTU to use for this link.
@hide
/**
     * Sets the Maximum Transmission Unit size to use on this link.  This should not be used
     * unless the system default (1500) is incorrect.  Values less than 68 or greater than
     * 10000 will be ignored.
     *
     * @param mtu The MTU to use for this link.
     * @hide
     */
    public void setMtu(int mtu) {
        mMtu = mtu;
    }

    
Gets any non-default MTU size set for this link.  Note that if the default is being used
this will return 0.

Returns:The mtu value set for this link.
@hide
/**
     * Gets any non-default MTU size set for this link.  Note that if the default is being used
     * this will return 0.
     *
     * @return The mtu value set for this link.
     * @hide
     */
    public int getMtu() {
        return mMtu;
    }

    
Sets the tcp buffers sizes to be used when this link is the system default.
Should be of the form "rmem_min,rmem_def,rmem_max,wmem_min,wmem_def,wmem_max".

Params:
  • tcpBufferSizes – The tcp buffers sizes to use.
@hide
/**
     * Sets the tcp buffers sizes to be used when this link is the system default.
     * Should be of the form "rmem_min,rmem_def,rmem_max,wmem_min,wmem_def,wmem_max".
     *
     * @param tcpBufferSizes The tcp buffers sizes to use.
     *
     * @hide
     */
    public void setTcpBufferSizes(String tcpBufferSizes) {
        mTcpBufferSizes = tcpBufferSizes;
    }

    
Gets the tcp buffer sizes.

Returns:the tcp buffer sizes to use when this link is the system default.
@hide
/**
     * Gets the tcp buffer sizes.
     *
     * @return the tcp buffer sizes to use when this link is the system default.
     *
     * @hide
     */
    public String getTcpBufferSizes() {
        return mTcpBufferSizes;
    }

    private RouteInfo routeWithInterface(RouteInfo route) {
        return new RouteInfo(
            route.getDestination(),
            route.getGateway(),
            mIfaceName,
            route.getType());
    }

    
Adds a RouteInfo to this LinkProperties, if not present. If the RouteInfo had an interface name set and that differs from the interface set for this LinkProperties an IllegalArgumentException will be thrown. The proper course is to add either un-named or properly named RouteInfo. 
Params:
Returns:false if the route was already present, true if it was added.
@hide
/**
     * Adds a {@link RouteInfo} to this {@code LinkProperties}, if not present. If the
     * {@link RouteInfo} had an interface name set and that differs from the interface set for this
     * {@code LinkProperties} an {@link IllegalArgumentException} will be thrown.  The proper
     * course is to add either un-named or properly named {@link RouteInfo}.
     *
     * @param route A {@link RouteInfo} to add to this object.
     * @return {@code false} if the route was already present, {@code true} if it was added.
     *
     * @hide
     */
    public boolean addRoute(RouteInfo route) {
        if (route != null) {
            String routeIface = route.getInterface();
            if (routeIface != null && !routeIface.equals(mIfaceName)) {
                throw new IllegalArgumentException(
                   "Route added with non-matching interface: " + routeIface +
                   " vs. " + mIfaceName);
            }
            route = routeWithInterface(route);
            if (!mRoutes.contains(route)) {
                mRoutes.add(route);
                return true;
            }
        }
        return false;
    }

    
Removes a RouteInfo from this LinkProperties, if present. The route must specify an interface and the interface must match the interface of this LinkProperties, or it will not be removed. 
Returns:true if the route was removed, false if it was not present.
@hide
/**
     * Removes a {@link RouteInfo} from this {@code LinkProperties}, if present. The route must
     * specify an interface and the interface must match the interface of this
     * {@code LinkProperties}, or it will not be removed.
     *
     * @return {@code true} if the route was removed, {@code false} if it was not present.
     *
     * @hide
     */
    public boolean removeRoute(RouteInfo route) {
        return route != null &&
                Objects.equals(mIfaceName, route.getInterface()) &&
                mRoutes.remove(route);
    }

    
Returns all the RouteInfo set on this link. 
Returns:An unmodifiable List of RouteInfo for this link.
/**
     * Returns all the {@link RouteInfo} set on this link.
     *
     * @return An unmodifiable {@link List} of {@link RouteInfo} for this link.
     */
    public List<RouteInfo> getRoutes() {
        return Collections.unmodifiableList(mRoutes);
    }

    
Make sure this LinkProperties instance contains routes that cover the local subnet
of its link addresses. Add any route that is missing.

@hide
/**
     * Make sure this LinkProperties instance contains routes that cover the local subnet
     * of its link addresses. Add any route that is missing.
     * @hide
     */
    public void ensureDirectlyConnectedRoutes() {
        for (LinkAddress addr: mLinkAddresses) {
            addRoute(new RouteInfo(addr, null, mIfaceName));
        }
    }

    
Returns all the routes on this link and all the links stacked above it.

@hide
/**
     * Returns all the routes on this link and all the links stacked above it.
     * @hide
     */
    public List<RouteInfo> getAllRoutes() {
        List<RouteInfo> routes = new ArrayList<>();
        routes.addAll(mRoutes);
        for (LinkProperties stacked: mStackedLinks.values()) {
            routes.addAll(stacked.getAllRoutes());
        }
        return routes;
    }

    
Sets the recommended ProxyInfo to use on this link, or null for none. Note that Http Proxies are only a hint - the system recommends their use, but it does not enforce it and applications may ignore them. 
Params:
  • proxy – A ProxyInfo defining the HTTP Proxy to use on this link.
@hide
/**
     * Sets the recommended {@link ProxyInfo} to use on this link, or {@code null} for none.
     * Note that Http Proxies are only a hint - the system recommends their use, but it does
     * not enforce it and applications may ignore them.
     *
     * @param proxy A {@link ProxyInfo} defining the HTTP Proxy to use on this link.
     * @hide
     */
    public void setHttpProxy(ProxyInfo proxy) {
        mHttpProxy = proxy;
    }

    
Gets the recommended ProxyInfo (or null) set on this link. 
Returns:The ProxyInfo set on this link
/**
     * Gets the recommended {@link ProxyInfo} (or {@code null}) set on this link.
     *
     * @return The {@link ProxyInfo} set on this link
     */
    public ProxyInfo getHttpProxy() {
        return mHttpProxy;
    }

    
Adds a stacked link.
If there is already a stacked link with the same interfacename as link,
that link is replaced with link. Otherwise, link is added to the list
of stacked links. If link is null, nothing changes.

Params:
  • link – The link to add.
Returns:true if the link was stacked, false otherwise.
@hide
/**
     * Adds a stacked link.
     *
     * If there is already a stacked link with the same interfacename as link,
     * that link is replaced with link. Otherwise, link is added to the list
     * of stacked links. If link is null, nothing changes.
     *
     * @param link The link to add.
     * @return true if the link was stacked, false otherwise.
     * @hide
     */
    public boolean addStackedLink(LinkProperties link) {
        if (link != null && link.getInterfaceName() != null) {
            mStackedLinks.put(link.getInterfaceName(), link);
            return true;
        }
        return false;
    }

    
Removes a stacked link.
If there is a stacked link with the given interface name, it is
removed. Otherwise, nothing changes.

Params:
  • iface – The interface name of the link to remove.
Returns:true if the link was removed, false otherwise.
@hide
/**
     * Removes a stacked link.
     *
     * If there is a stacked link with the given interface name, it is
     * removed. Otherwise, nothing changes.
     *
     * @param iface The interface name of the link to remove.
     * @return true if the link was removed, false otherwise.
     * @hide
     */
    public boolean removeStackedLink(String iface) {
        if (iface != null) {
            LinkProperties removed = mStackedLinks.remove(iface);
            return removed != null;
        }
        return false;
    }

    
Returns all the links stacked on top of this link.

@hide
/**
     * Returns all the links stacked on top of this link.
     * @hide
     */
    public @NonNull List<LinkProperties> getStackedLinks() {
        if (mStackedLinks.isEmpty()) {
            return Collections.EMPTY_LIST;
        }
        List<LinkProperties> stacked = new ArrayList<LinkProperties>();
        for (LinkProperties link : mStackedLinks.values()) {
            stacked.add(new LinkProperties(link));
        }
        return Collections.unmodifiableList(stacked);
    }

    
Clears this object to its initial state.

@hide
/**
     * Clears this object to its initial state.
     * @hide
     */
    public void clear() {
        mIfaceName = null;
        mLinkAddresses.clear();
        mDnses.clear();
        mUsePrivateDns = false;
        mPrivateDnsServerName = null;
        mDomains = null;
        mRoutes.clear();
        mHttpProxy = null;
        mStackedLinks.clear();
        mMtu = 0;
        mTcpBufferSizes = null;
    }

    
Implement the Parcelable interface

/**
     * Implement the Parcelable interface
     */
    public int describeContents() {
        return 0;
    }

    @Override
    public String toString() {
        String ifaceName = (mIfaceName == null ? "" : "InterfaceName: " + mIfaceName + " ");

        String linkAddresses = "LinkAddresses: [";
        for (LinkAddress addr : mLinkAddresses) linkAddresses += addr.toString() + ",";
        linkAddresses += "] ";

        String dns = "DnsAddresses: [";
        for (InetAddress addr : mDnses) dns += addr.getHostAddress() + ",";
        dns += "] ";

        String usePrivateDns = "UsePrivateDns: " + mUsePrivateDns + " ";

        String privateDnsServerName = "";
        if (privateDnsServerName != null) {
            privateDnsServerName = "PrivateDnsServerName: " + mPrivateDnsServerName + " ";
        }

        String validatedPrivateDns = "";
        if (!mValidatedPrivateDnses.isEmpty()) {
            validatedPrivateDns = "ValidatedPrivateDnsAddresses: [";
            for (InetAddress addr : mValidatedPrivateDnses) {
                validatedPrivateDns += addr.getHostAddress() + ",";
            }
            validatedPrivateDns += "] ";
        }

        String domainName = "Domains: " + mDomains;

        String mtu = " MTU: " + mMtu;

        String tcpBuffSizes = "";
        if (mTcpBufferSizes != null) {
            tcpBuffSizes = " TcpBufferSizes: " + mTcpBufferSizes;
        }

        String routes = " Routes: [";
        for (RouteInfo route : mRoutes) routes += route.toString() + ",";
        routes += "] ";
        String proxy = (mHttpProxy == null ? "" : " HttpProxy: " + mHttpProxy.toString() + " ");

        String stacked = "";
        if (mStackedLinks.values().size() > 0) {
            stacked += " Stacked: [";
            for (LinkProperties link: mStackedLinks.values()) {
                stacked += " [" + link.toString() + " ],";
            }
            stacked += "] ";
        }
        return "{" + ifaceName + linkAddresses + routes + dns + usePrivateDns
            + privateDnsServerName + domainName + mtu + tcpBuffSizes + proxy
            + stacked + "}";
    }

    
Returns true if this link has an IPv4 address.

Returns:true if there is an IPv4 address, false otherwise.
@hide
/**
     * Returns true if this link has an IPv4 address.
     *
     * @return {@code true} if there is an IPv4 address, {@code false} otherwise.
     * @hide
     */
    public boolean hasIPv4Address() {
        for (LinkAddress address : mLinkAddresses) {
            if (address.getAddress() instanceof Inet4Address) {
                return true;
            }
        }
        return false;
    }

    
Returns true if this link or any of its stacked interfaces has an IPv4 address.

Returns:true if there is an IPv4 address, false otherwise.
/**
     * Returns true if this link or any of its stacked interfaces has an IPv4 address.
     *
     * @return {@code true} if there is an IPv4 address, {@code false} otherwise.
     */
    private boolean hasIPv4AddressOnInterface(String iface) {
        // mIfaceName can be null.
        return (Objects.equals(iface, mIfaceName) && hasIPv4Address()) ||
                (iface != null && mStackedLinks.containsKey(iface) &&
                        mStackedLinks.get(iface).hasIPv4Address());
    }

    
Returns true if this link has a global preferred IPv6 address.

Returns:true if there is a global preferred IPv6 address, false otherwise.
@hide
/**
     * Returns true if this link has a global preferred IPv6 address.
     *
     * @return {@code true} if there is a global preferred IPv6 address, {@code false} otherwise.
     * @hide
     */
    public boolean hasGlobalIPv6Address() {
        for (LinkAddress address : mLinkAddresses) {
          if (address.getAddress() instanceof Inet6Address && address.isGlobalPreferred()) {
            return true;
          }
        }
        return false;
    }

    
Returns true if this link has an IPv4 default route.

Returns:true if there is an IPv4 default route, false otherwise.
@hide
/**
     * Returns true if this link has an IPv4 default route.
     *
     * @return {@code true} if there is an IPv4 default route, {@code false} otherwise.
     * @hide
     */
    public boolean hasIPv4DefaultRoute() {
        for (RouteInfo r : mRoutes) {
            if (r.isIPv4Default()) {
                return true;
            }
        }
        return false;
    }

    
Returns true if this link has an IPv6 default route.

Returns:true if there is an IPv6 default route, false otherwise.
@hide
/**
     * Returns true if this link has an IPv6 default route.
     *
     * @return {@code true} if there is an IPv6 default route, {@code false} otherwise.
     * @hide
     */
    public boolean hasIPv6DefaultRoute() {
        for (RouteInfo r : mRoutes) {
            if (r.isIPv6Default()) {
                return true;
            }
        }
        return false;
    }

    
Returns true if this link has an IPv4 DNS server.

Returns:true if there is an IPv4 DNS server, false otherwise.
@hide
/**
     * Returns true if this link has an IPv4 DNS server.
     *
     * @return {@code true} if there is an IPv4 DNS server, {@code false} otherwise.
     * @hide
     */
    public boolean hasIPv4DnsServer() {
        for (InetAddress ia : mDnses) {
            if (ia instanceof Inet4Address) {
                return true;
            }
        }
        return false;
    }

    
Returns true if this link has an IPv6 DNS server.

Returns:true if there is an IPv6 DNS server, false otherwise.
@hide
/**
     * Returns true if this link has an IPv6 DNS server.
     *
     * @return {@code true} if there is an IPv6 DNS server, {@code false} otherwise.
     * @hide
     */
    public boolean hasIPv6DnsServer() {
        for (InetAddress ia : mDnses) {
            if (ia instanceof Inet6Address) {
                return true;
            }
        }
        return false;
    }

    
Returns true if this link is provisioned for global IPv4 connectivity.
This requires an IP address, default route, and DNS server.

Returns:true if the link is provisioned, false otherwise.
@hide
/**
     * Returns true if this link is provisioned for global IPv4 connectivity.
     * This requires an IP address, default route, and DNS server.
     *
     * @return {@code true} if the link is provisioned, {@code false} otherwise.
     * @hide
     */
    public boolean isIPv4Provisioned() {
        return (hasIPv4Address() &&
                hasIPv4DefaultRoute() &&
                hasIPv4DnsServer());
    }

    
Returns true if this link is provisioned for global IPv6 connectivity.
This requires an IP address, default route, and DNS server.

Returns:true if the link is provisioned, false otherwise.
@hide
/**
     * Returns true if this link is provisioned for global IPv6 connectivity.
     * This requires an IP address, default route, and DNS server.
     *
     * @return {@code true} if the link is provisioned, {@code false} otherwise.
     * @hide
     */
    public boolean isIPv6Provisioned() {
        return (hasGlobalIPv6Address() &&
                hasIPv6DefaultRoute() &&
                hasIPv6DnsServer());
    }

    
Returns true if this link is provisioned for global connectivity,
for at least one Internet Protocol family.

Returns:true if the link is provisioned, false otherwise.
@hide
/**
     * Returns true if this link is provisioned for global connectivity,
     * for at least one Internet Protocol family.
     *
     * @return {@code true} if the link is provisioned, {@code false} otherwise.
     * @hide
     */
    public boolean isProvisioned() {
        return (isIPv4Provisioned() || isIPv6Provisioned());
    }

    
Evaluate whether the InetAddress is considered reachable. 
Returns:true if the given InetAddress is considered reachable, false otherwise.
@hide
/**
     * Evaluate whether the {@link InetAddress} is considered reachable.
     *
     * @return {@code true} if the given {@link InetAddress} is considered reachable,
     *         {@code false} otherwise.
     * @hide
     */
    public boolean isReachable(InetAddress ip) {
        final List<RouteInfo> allRoutes = getAllRoutes();
        // If we don't have a route to this IP address, it's not reachable.
        final RouteInfo bestRoute = RouteInfo.selectBestRoute(allRoutes, ip);
        if (bestRoute == null) {
            return false;
        }

        // TODO: better source address evaluation for destination addresses.

        if (ip instanceof Inet4Address) {
            // For IPv4, it suffices for now to simply have any address.
            return hasIPv4AddressOnInterface(bestRoute.getInterface());
        } else if (ip instanceof Inet6Address) {
            if (ip.isLinkLocalAddress()) {
                // For now, just make sure link-local destinations have
                // scopedIds set, since transmits will generally fail otherwise.
                // TODO: verify it matches the ifindex of one of the interfaces.
                return (((Inet6Address)ip).getScopeId() != 0);
            }  else {
                // For non-link-local destinations check that either the best route
                // is directly connected or that some global preferred address exists.
                // TODO: reconsider all cases (disconnected ULA networks, ...).
                return (!bestRoute.hasGateway() || hasGlobalIPv6Address());
            }
        }

        return false;
    }

    
Compares this LinkProperties interface name against the target 
Params:
  • target – LinkProperties to compare.
Returns:true if both are identical, false otherwise.
@hide
/**
     * Compares this {@code LinkProperties} interface name against the target
     *
     * @param target LinkProperties to compare.
     * @return {@code true} if both are identical, {@code false} otherwise.
     * @hide
     */
    public boolean isIdenticalInterfaceName(LinkProperties target) {
        return TextUtils.equals(getInterfaceName(), target.getInterfaceName());
    }

    
Compares this LinkProperties interface addresses against the target 
Params:
  • target – LinkProperties to compare.
Returns:true if both are identical, false otherwise.
@hide
/**
     * Compares this {@code LinkProperties} interface addresses against the target
     *
     * @param target LinkProperties to compare.
     * @return {@code true} if both are identical, {@code false} otherwise.
     * @hide
     */
    public boolean isIdenticalAddresses(LinkProperties target) {
        Collection<InetAddress> targetAddresses = target.getAddresses();
        Collection<InetAddress> sourceAddresses = getAddresses();
        return (sourceAddresses.size() == targetAddresses.size()) ?
                    sourceAddresses.containsAll(targetAddresses) : false;
    }

    
Compares this LinkProperties DNS addresses against the target 
Params:
  • target – LinkProperties to compare.
Returns:true if both are identical, false otherwise.
@hide
/**
     * Compares this {@code LinkProperties} DNS addresses against the target
     *
     * @param target LinkProperties to compare.
     * @return {@code true} if both are identical, {@code false} otherwise.
     * @hide
     */
    public boolean isIdenticalDnses(LinkProperties target) {
        Collection<InetAddress> targetDnses = target.getDnsServers();
        String targetDomains = target.getDomains();
        if (mDomains == null) {
            if (targetDomains != null) return false;
        } else {
            if (mDomains.equals(targetDomains) == false) return false;
        }
        return (mDnses.size() == targetDnses.size()) ?
                mDnses.containsAll(targetDnses) : false;
    }

    
Compares this LinkProperties private DNS settings against the target. 
Params:
  • target – LinkProperties to compare.
Returns:true if both are identical, false otherwise.
@hide
/**
     * Compares this {@code LinkProperties} private DNS settings against the
     * target.
     *
     * @param target LinkProperties to compare.
     * @return {@code true} if both are identical, {@code false} otherwise.
     * @hide
     */
    public boolean isIdenticalPrivateDns(LinkProperties target) {
        return (isPrivateDnsActive() == target.isPrivateDnsActive()
                && TextUtils.equals(getPrivateDnsServerName(),
                target.getPrivateDnsServerName()));
    }

    
Compares this LinkProperties validated private DNS addresses against the target 
Params:
  • target – LinkProperties to compare.
Returns:true if both are identical, false otherwise.
@hide
/**
     * Compares this {@code LinkProperties} validated private DNS addresses against
     * the target
     *
     * @param target LinkProperties to compare.
     * @return {@code true} if both are identical, {@code false} otherwise.
     * @hide
     */
    public boolean isIdenticalValidatedPrivateDnses(LinkProperties target) {
        Collection<InetAddress> targetDnses = target.getValidatedPrivateDnsServers();
        return (mValidatedPrivateDnses.size() == targetDnses.size())
                ? mValidatedPrivateDnses.containsAll(targetDnses) : false;
    }

    
Compares this LinkProperties Routes against the target 
Params:
  • target – LinkProperties to compare.
Returns:true if both are identical, false otherwise.
@hide
/**
     * Compares this {@code LinkProperties} Routes against the target
     *
     * @param target LinkProperties to compare.
     * @return {@code true} if both are identical, {@code false} otherwise.
     * @hide
     */
    public boolean isIdenticalRoutes(LinkProperties target) {
        Collection<RouteInfo> targetRoutes = target.getRoutes();
        return (mRoutes.size() == targetRoutes.size()) ?
                mRoutes.containsAll(targetRoutes) : false;
    }

    
Compares this LinkProperties HttpProxy against the target 
Params:
  • target – LinkProperties to compare.
Returns:true if both are identical, false otherwise.
@hide
/**
     * Compares this {@code LinkProperties} HttpProxy against the target
     *
     * @param target LinkProperties to compare.
     * @return {@code true} if both are identical, {@code false} otherwise.
     * @hide
     */
    public boolean isIdenticalHttpProxy(LinkProperties target) {
        return getHttpProxy() == null ? target.getHttpProxy() == null :
                getHttpProxy().equals(target.getHttpProxy());
    }

    
Compares this LinkProperties stacked links against the target 
Params:
  • target – LinkProperties to compare.
Returns:true if both are identical, false otherwise.
@hide
/**
     * Compares this {@code LinkProperties} stacked links against the target
     *
     * @param target LinkProperties to compare.
     * @return {@code true} if both are identical, {@code false} otherwise.
     * @hide
     */
    public boolean isIdenticalStackedLinks(LinkProperties target) {
        if (!mStackedLinks.keySet().equals(target.mStackedLinks.keySet())) {
            return false;
        }
        for (LinkProperties stacked : mStackedLinks.values()) {
            // Hashtable values can never be null.
            String iface = stacked.getInterfaceName();
            if (!stacked.equals(target.mStackedLinks.get(iface))) {
                return false;
            }
        }
        return true;
    }

    
Compares this LinkProperties MTU against the target 
Params:
  • target – LinkProperties to compare.
Returns:true if both are identical, false otherwise.
@hide
/**
     * Compares this {@code LinkProperties} MTU against the target
     *
     * @param target LinkProperties to compare.
     * @return {@code true} if both are identical, {@code false} otherwise.
     * @hide
     */
    public boolean isIdenticalMtu(LinkProperties target) {
        return getMtu() == target.getMtu();
    }

    
Compares this LinkProperties Tcp buffer sizes against the target. 
Params:
  • target – LinkProperties to compare.
Returns:true if both are identical, false otherwise.
@hide
/**
     * Compares this {@code LinkProperties} Tcp buffer sizes against the target.
     *
     * @param target LinkProperties to compare.
     * @return {@code true} if both are identical, {@code false} otherwise.
     * @hide
     */
    public boolean isIdenticalTcpBufferSizes(LinkProperties target) {
        return Objects.equals(mTcpBufferSizes, target.mTcpBufferSizes);
    }

    @Override
    /**
     * Compares this {@code LinkProperties} instance against the target
     * LinkProperties in {@code obj}. Two LinkPropertieses are equal if
     * all their fields are equal in values.
     *
     * For collection fields, such as mDnses, containsAll() is used to check
     * if two collections contains the same elements, independent of order.
     * There are two thoughts regarding containsAll()
     * 1. Duplicated elements. eg, (A, B, B) and (A, A, B) are equal.
     * 2. Worst case performance is O(n^2).
     *
     * @param obj the object to be tested for equality.
     * @return {@code true} if both objects are equal, {@code false} otherwise.
     */
    public boolean equals(Object obj) {
        if (this == obj) return true;

        if (!(obj instanceof LinkProperties)) return false;

        LinkProperties target = (LinkProperties) obj;
        /**
         * This method does not check that stacked interfaces are equal, because
         * stacked interfaces are not so much a property of the link as a
         * description of connections between links.
         */
        return isIdenticalInterfaceName(target)
                && isIdenticalAddresses(target)
                && isIdenticalDnses(target)
                && isIdenticalPrivateDns(target)
                && isIdenticalValidatedPrivateDnses(target)
                && isIdenticalRoutes(target)
                && isIdenticalHttpProxy(target)
                && isIdenticalStackedLinks(target)
                && isIdenticalMtu(target)
                && isIdenticalTcpBufferSizes(target);
    }

    
Compares the addresses in this LinkProperties with another
LinkProperties, examining only addresses on the base link.

Params:
  • target – a LinkProperties with the new list of addresses
Returns:the differences between the addresses.
@hide
/**
     * Compares the addresses in this LinkProperties with another
     * LinkProperties, examining only addresses on the base link.
     *
     * @param target a LinkProperties with the new list of addresses
     * @return the differences between the addresses.
     * @hide
     */
    public CompareResult<LinkAddress> compareAddresses(LinkProperties target) {
        /*
         * Duplicate the LinkAddresses into removed, we will be removing
         * address which are common between mLinkAddresses and target
         * leaving the addresses that are different. And address which
         * are in target but not in mLinkAddresses are placed in the
         * addedAddresses.
         */
        return new CompareResult<>(mLinkAddresses,
                target != null ? target.getLinkAddresses() : null);
    }

    
Compares the DNS addresses in this LinkProperties with another
LinkProperties, examining only DNS addresses on the base link.

Params:
  • target – a LinkProperties with the new list of dns addresses
Returns:the differences between the DNS addresses.
@hide
/**
     * Compares the DNS addresses in this LinkProperties with another
     * LinkProperties, examining only DNS addresses on the base link.
     *
     * @param target a LinkProperties with the new list of dns addresses
     * @return the differences between the DNS addresses.
     * @hide
     */
    public CompareResult<InetAddress> compareDnses(LinkProperties target) {
        /*
         * Duplicate the InetAddresses into removed, we will be removing
         * dns address which are common between mDnses and target
         * leaving the addresses that are different. And dns address which
         * are in target but not in mDnses are placed in the
         * addedAddresses.
         */
        return new CompareResult<>(mDnses, target != null ? target.getDnsServers() : null);
    }

    
Compares the validated private DNS addresses in this LinkProperties with another
LinkProperties.

Params:
  • target – a LinkProperties with the new list of validated private dns addresses
Returns:the differences between the DNS addresses.
@hide
/**
     * Compares the validated private DNS addresses in this LinkProperties with another
     * LinkProperties.
     *
     * @param target a LinkProperties with the new list of validated private dns addresses
     * @return the differences between the DNS addresses.
     * @hide
     */
    public CompareResult<InetAddress> compareValidatedPrivateDnses(LinkProperties target) {
        return new CompareResult<>(mValidatedPrivateDnses,
                target != null ? target.getValidatedPrivateDnsServers() : null);
    }

    
Compares all routes in this LinkProperties with another LinkProperties,
examining both the the base link and all stacked links.

Params:
  • target – a LinkProperties with the new list of routes
Returns:the differences between the routes.
@hide
/**
     * Compares all routes in this LinkProperties with another LinkProperties,
     * examining both the the base link and all stacked links.
     *
     * @param target a LinkProperties with the new list of routes
     * @return the differences between the routes.
     * @hide
     */
    public CompareResult<RouteInfo> compareAllRoutes(LinkProperties target) {
        /*
         * Duplicate the RouteInfos into removed, we will be removing
         * routes which are common between mRoutes and target
         * leaving the routes that are different. And route address which
         * are in target but not in mRoutes are placed in added.
         */
        return new CompareResult<>(getAllRoutes(), target != null ? target.getAllRoutes() : null);
    }

    
Compares all interface names in this LinkProperties with another
LinkProperties, examining both the the base link and all stacked links.

Params:
  • target – a LinkProperties with the new list of interface names
Returns:the differences between the interface names.
@hide
/**
     * Compares all interface names in this LinkProperties with another
     * LinkProperties, examining both the the base link and all stacked links.
     *
     * @param target a LinkProperties with the new list of interface names
     * @return the differences between the interface names.
     * @hide
     */
    public CompareResult<String> compareAllInterfaceNames(LinkProperties target) {
        /*
         * Duplicate the interface names into removed, we will be removing
         * interface names which are common between this and target
         * leaving the interface names that are different. And interface names which
         * are in target but not in this are placed in added.
         */
        return new CompareResult<>(getAllInterfaceNames(),
                target != null ? target.getAllInterfaceNames() : null);
    }


    @Override
    /**
     * generate hashcode based on significant fields
     * Equal objects must produce the same hash code, while unequal objects
     * may have the same hash codes.
     */
    public int hashCode() {
        return ((null == mIfaceName) ? 0 : mIfaceName.hashCode()
                + mLinkAddresses.size() * 31
                + mDnses.size() * 37
                + mValidatedPrivateDnses.size() * 61
                + ((null == mDomains) ? 0 : mDomains.hashCode())
                + mRoutes.size() * 41
                + ((null == mHttpProxy) ? 0 : mHttpProxy.hashCode())
                + mStackedLinks.hashCode() * 47)
                + mMtu * 51
                + ((null == mTcpBufferSizes) ? 0 : mTcpBufferSizes.hashCode())
                + (mUsePrivateDns ? 57 : 0)
                + ((null == mPrivateDnsServerName) ? 0 : mPrivateDnsServerName.hashCode());
    }

    
Implement the Parcelable interface.

/**
     * Implement the Parcelable interface.
     */
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeString(getInterfaceName());
        dest.writeInt(mLinkAddresses.size());
        for (LinkAddress linkAddress : mLinkAddresses) {
            dest.writeParcelable(linkAddress, flags);
        }

        dest.writeInt(mDnses.size());
        for (InetAddress d : mDnses) {
            dest.writeByteArray(d.getAddress());
        }
        dest.writeInt(mValidatedPrivateDnses.size());
        for (InetAddress d : mValidatedPrivateDnses) {
            dest.writeByteArray(d.getAddress());
        }
        dest.writeBoolean(mUsePrivateDns);
        dest.writeString(mPrivateDnsServerName);
        dest.writeString(mDomains);
        dest.writeInt(mMtu);
        dest.writeString(mTcpBufferSizes);
        dest.writeInt(mRoutes.size());
        for (RouteInfo route : mRoutes) {
            dest.writeParcelable(route, flags);
        }

        if (mHttpProxy != null) {
            dest.writeByte((byte)1);
            dest.writeParcelable(mHttpProxy, flags);
        } else {
            dest.writeByte((byte)0);
        }
        ArrayList<LinkProperties> stackedLinks = new ArrayList(mStackedLinks.values());
        dest.writeList(stackedLinks);
    }

    
Implement the Parcelable interface.

/**
     * Implement the Parcelable interface.
     */
    public static final Creator<LinkProperties> CREATOR =
        new Creator<LinkProperties>() {
            public LinkProperties createFromParcel(Parcel in) {
                LinkProperties netProp = new LinkProperties();

                String iface = in.readString();
                if (iface != null) {
                    netProp.setInterfaceName(iface);
                }
                int addressCount = in.readInt();
                for (int i = 0; i < addressCount; i++) {
                    netProp.addLinkAddress((LinkAddress) in.readParcelable(null));
                }
                addressCount = in.readInt();
                for (int i = 0; i < addressCount; i++) {
                    try {
                        netProp.addDnsServer(InetAddress.getByAddress(in.createByteArray()));
                    } catch (UnknownHostException e) { }
                }
                addressCount = in.readInt();
                for (int i = 0; i < addressCount; i++) {
                    try {
                        netProp.addValidatedPrivateDnsServer(
                                InetAddress.getByAddress(in.createByteArray()));
                    } catch (UnknownHostException e) { }
                }
                netProp.setUsePrivateDns(in.readBoolean());
                netProp.setPrivateDnsServerName(in.readString());
                netProp.setDomains(in.readString());
                netProp.setMtu(in.readInt());
                netProp.setTcpBufferSizes(in.readString());
                addressCount = in.readInt();
                for (int i = 0; i < addressCount; i++) {
                    netProp.addRoute((RouteInfo) in.readParcelable(null));
                }
                if (in.readByte() == 1) {
                    netProp.setHttpProxy((ProxyInfo) in.readParcelable(null));
                }
                ArrayList<LinkProperties> stackedLinks = new ArrayList<LinkProperties>();
                in.readList(stackedLinks, LinkProperties.class.getClassLoader());
                for (LinkProperties stackedLink: stackedLinks) {
                    netProp.addStackedLink(stackedLink);
                }
                return netProp;
            }

            public LinkProperties[] newArray(int size) {
                return new LinkProperties[size];
            }
        };

    
Check the valid MTU range based on IPv4 or IPv6.

@hide
/**
     * Check the valid MTU range based on IPv4 or IPv6.
     * @hide
     */
    public static boolean isValidMtu(int mtu, boolean ipv6) {
        if (ipv6) {
            if (mtu >= MIN_MTU_V6 && mtu <= MAX_MTU) return true;
        } else {
            if (mtu >= MIN_MTU && mtu <= MAX_MTU) return true;
        }
        return false;
    }
}