1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27
28 package org.apache.http.conn.routing;
29
30 /**
31 * Provides directions on establishing a route.
32 * Implementations of this interface compare a planned route with
33 * a tracked route and indicate the next step required.
34 *
35 * @since 4.0
36 */
37 public interface HttpRouteDirector {
38
39 /** Indicates that the route can not be established at all. */
40 int UNREACHABLE = -1;
41
42 /** Indicates that the route is complete. */
43 int COMPLETE = 0;
44
45 /** Step: open connection to target. */
46 int CONNECT_TARGET = 1;
47
48 /** Step: open connection to proxy. */
49 int CONNECT_PROXY = 2;
50
51 /** Step: tunnel through proxy to target. */
52 int TUNNEL_TARGET = 3;
53
54 /** Step: tunnel through proxy to other proxy. */
55 int TUNNEL_PROXY = 4;
56
57 /** Step: layer protocol (over tunnel). */
58 int LAYER_PROTOCOL = 5;
59
60
61 /**
62 * Provides the next step.
63 *
64 * @param plan the planned route
65 * @param fact the currently established route, or
66 * {@code null} if nothing is established
67 *
68 * @return one of the constants defined in this interface, indicating
69 * either the next step to perform, or success, or failure.
70 * 0 is for success, a negative value for failure.
71 */
72 int nextStep(RouteInfo"../../../../../org/apache/http/conn/routing/RouteInfo.html#RouteInfo">RouteInfo plan, RouteInfo fact);
73
74 }