michael@0: /*
michael@0:  * ====================================================================
michael@0:  * Licensed to the Apache Software Foundation (ASF) under one
michael@0:  * or more contributor license agreements.  See the NOTICE file
michael@0:  * distributed with this work for additional information
michael@0:  * regarding copyright ownership.  The ASF licenses this file
michael@0:  * to you under the Apache License, Version 2.0 (the
michael@0:  * "License"); you may not use this file except in compliance
michael@0:  * with the License.  You may obtain a copy of the License at
michael@0:  *
michael@0:  *   http://www.apache.org/licenses/LICENSE-2.0
michael@0:  *
michael@0:  * Unless required by applicable law or agreed to in writing,
michael@0:  * software distributed under the License is distributed on an
michael@0:  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
michael@0:  * KIND, either express or implied.  See the License for the
michael@0:  * specific language governing permissions and limitations
michael@0:  * under the License.
michael@0:  * ====================================================================
michael@0:  *
michael@0:  * This software consists of voluntary contributions made by many
michael@0:  * individuals on behalf of the Apache Software Foundation.  For more
michael@0:  * information on the Apache Software Foundation, please see
michael@0:  * <http://www.apache.org/>.
michael@0:  *
michael@0:  */
michael@0: 
michael@0: package ch.boye.httpclientandroidlib.conn.routing;
michael@0: 
michael@0: import java.net.InetAddress;
michael@0: 
michael@0: import ch.boye.httpclientandroidlib.HttpHost;
michael@0: 
michael@0: /**
michael@0:  * Read-only interface for route information.
michael@0:  *
michael@0:  * @since 4.0
michael@0:  */
michael@0: public interface RouteInfo {
michael@0: 
michael@0:     /**
michael@0:      * The tunnelling type of a route.
michael@0:      * Plain routes are established by   connecting to the target or
michael@0:      * the first proxy.
michael@0:      * Tunnelled routes are established by connecting to the first proxy
michael@0:      * and tunnelling through all proxies to the target.
michael@0:      * Routes without a proxy cannot be tunnelled.
michael@0:      */
michael@0:     public enum TunnelType { PLAIN, TUNNELLED }
michael@0: 
michael@0:     /**
michael@0:      * The layering type of a route.
michael@0:      * Plain routes are established by connecting or tunnelling.
michael@0:      * Layered routes are established by layering a protocol such as TLS/SSL
michael@0:      * over an existing connection.
michael@0:      * Protocols can only be layered over a tunnel to the target, or
michael@0:      * or over a direct connection without proxies.
michael@0:      * <br/>
michael@0:      * Layering a protocol
michael@0:      * over a direct connection makes little sense, since the connection
michael@0:      * could be established with the new protocol in the first place.
michael@0:      * But we don't want to exclude that use case.
michael@0:      */
michael@0:     public enum LayerType  { PLAIN, LAYERED }
michael@0: 
michael@0:     /**
michael@0:      * Obtains the target host.
michael@0:      *
michael@0:      * @return the target host
michael@0:      */
michael@0:     HttpHost getTargetHost();
michael@0: 
michael@0:     /**
michael@0:      * Obtains the local address to connect from.
michael@0:      *
michael@0:      * @return  the local address,
michael@0:      *          or <code>null</code>
michael@0:      */
michael@0:     InetAddress getLocalAddress();
michael@0: 
michael@0:     /**
michael@0:      * Obtains the number of hops in this route.
michael@0:      * A direct route has one hop. A route through a proxy has two hops.
michael@0:      * A route through a chain of <i>n</i> proxies has <i>n+1</i> hops.
michael@0:      *
michael@0:      * @return  the number of hops in this route
michael@0:      */
michael@0:     int getHopCount();
michael@0: 
michael@0:     /**
michael@0:      * Obtains the target of a hop in this route.
michael@0:      * The target of the last hop is the {@link #getTargetHost target host},
michael@0:      * the target of previous hops is the respective proxy in the chain.
michael@0:      * For a route through exactly one proxy, target of hop 0 is the proxy
michael@0:      * and target of hop 1 is the target host.
michael@0:      *
michael@0:      * @param hop       index of the hop for which to get the target,
michael@0:      *                  0 for first
michael@0:      *
michael@0:      * @return  the target of the given hop
michael@0:      *
michael@0:      * @throws IllegalArgumentException
michael@0:      *  if the argument is negative or not less than
michael@0:      *  {@link #getHopCount getHopCount()}
michael@0:      */
michael@0:     HttpHost getHopTarget(int hop);
michael@0: 
michael@0:     /**
michael@0:      * Obtains the first proxy host.
michael@0:      *
michael@0:      * @return the first proxy in the proxy chain, or
michael@0:      *         <code>null</code> if this route is direct
michael@0:      */
michael@0:     HttpHost getProxyHost();
michael@0: 
michael@0:     /**
michael@0:      * Obtains the tunnel type of this route.
michael@0:      * If there is a proxy chain, only end-to-end tunnels are considered.
michael@0:      *
michael@0:      * @return  the tunnelling type
michael@0:      */
michael@0:     TunnelType getTunnelType();
michael@0: 
michael@0:     /**
michael@0:      * Checks whether this route is tunnelled through a proxy.
michael@0:      * If there is a proxy chain, only end-to-end tunnels are considered.
michael@0:      *
michael@0:      * @return  <code>true</code> if tunnelled end-to-end through at least
michael@0:      *          one proxy,
michael@0:      *          <code>false</code> otherwise
michael@0:      */
michael@0:     boolean isTunnelled();
michael@0: 
michael@0:     /**
michael@0:      * Obtains the layering type of this route.
michael@0:      * In the presence of proxies, only layering over an end-to-end tunnel
michael@0:      * is considered.
michael@0:      *
michael@0:      * @return  the layering type
michael@0:      */
michael@0:     LayerType getLayerType();
michael@0: 
michael@0:     /**
michael@0:      * Checks whether this route includes a layered protocol.
michael@0:      * In the presence of proxies, only layering over an end-to-end tunnel
michael@0:      * is considered.
michael@0:      *
michael@0:      * @return  <code>true</code> if layered,
michael@0:      *          <code>false</code> otherwise
michael@0:      */
michael@0:     boolean isLayered();
michael@0: 
michael@0:     /**
michael@0:      * Checks whether this route is secure.
michael@0:      *
michael@0:      * @return  <code>true</code> if secure,
michael@0:      *          <code>false</code> otherwise
michael@0:      */
michael@0:     boolean isSecure();
michael@0: 
michael@0: }