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;
29
30 import java.io.IOException;
31 import java.util.concurrent.TimeUnit;
32
33 import javax.net.ssl.SSLSession;
34
35 import org.apache.http.HttpClientConnection;
36 import org.apache.http.HttpHost;
37 import org.apache.http.params.HttpParams;
38 import org.apache.http.protocol.HttpContext;
39
40 import org.apache.http.conn.routing.HttpRoute;
41
42 /**
43 * A client-side connection with advanced connection logic.
44 * Instances are typically obtained from a connection manager.
45 *
46 * @since 4.0
47 */
48 public interface ManagedClientConnection extends
49 HttpClientConnection, HttpRoutedConnection, ConnectionReleaseTrigger {
50
51 /**
52 * Indicates whether this connection is secure.
53 * The return value is well-defined only while the connection is open.
54 * It may change even while the connection is open.
55 *
56 * @return <code>true</code> if this connection is secure,
57 * <code>false</code> otherwise
58 */
59 boolean isSecure();
60
61 /**
62 * Obtains the current route of this connection.
63 *
64 * @return the route established so far, or
65 * <code>null</code> if not connected
66 */
67 HttpRoute getRoute();
68
69 /**
70 * Obtains the SSL session of the underlying connection, if any.
71 * If this connection is open, and the underlying socket is an
72 * {@link javax.net.ssl.SSLSocket SSLSocket}, the SSL session of
73 * that socket is obtained. This is a potentially blocking operation.
74 * <br/>
75 * <b>Note:</b> Whether the underlying socket is an SSL socket
76 * can not necessarily be determined via {@link #isSecure}.
77 * Plain sockets may be considered secure, for example if they are
78 * connected to a known host in the same network segment.
79 * On the other hand, SSL sockets may be considered insecure,
80 * for example depending on the chosen cipher suite.
81 *
82 * @return the underlying SSL session if available,
83 * <code>null</code> otherwise
84 */
85 SSLSession getSSLSession();
86
87 /**
88 * Opens this connection according to the given route.
89 *
90 * @param route the route along which to open. It will be opened to
91 * the first proxy if present, or directly to the target.
92 * @param context the context for opening this connection
93 * @param params the parameters for opening this connection
94 *
95 * @throws IOException in case of a problem
96 */
97 void open(HttpRoute route, HttpContext context, HttpParams params)
98 throws IOException;
99
100 /**
101 * Indicates that a tunnel to the target has been established.
102 * The route is the one previously passed to {@link #open open}.
103 * Subsequently, {@link #layerProtocol layerProtocol} can be called
104 * to layer the TLS/SSL protocol on top of the tunnelled connection.
105 * <br/>
106 * <b>Note:</b> In HttpClient 3, a call to the corresponding method
107 * would automatically trigger the layering of the TLS/SSL protocol.
108 * This is not the case anymore, you can establish a tunnel without
109 * layering a new protocol over the connection.
110 *
111 * @param secure <code>true</code> if the tunnel should be considered
112 * secure, <code>false</code> otherwise
113 * @param params the parameters for tunnelling this connection
114 *
115 * @throws IOException in case of a problem
116 */
117 void tunnelTarget(boolean secure, HttpParams params)
118 throws IOException;
119
120 /**
121 * Indicates that a tunnel to an intermediate proxy has been established.
122 * This is used exclusively for so-called <i>proxy chains</i>, where
123 * a request has to pass through multiple proxies before reaching the
124 * target. In that case, all proxies but the last need to be tunnelled
125 * when establishing the connection. Tunnelling of the last proxy to the
126 * target is optional and would be indicated via {@link #tunnelTarget}.
127 *
128 * @param next the proxy to which the tunnel was established.
129 * This is <i>not</i> the proxy <i>through</i> which
130 * the tunnel was established, but the new end point
131 * of the tunnel. The tunnel does <i>not</i> yet
132 * reach to the target, use {@link #tunnelTarget}
133 * to indicate an end-to-end tunnel.
134 * @param secure <code>true</code> if the connection should be
135 * considered secure, <code>false</code> otherwise
136 * @param params the parameters for tunnelling this connection
137 *
138 * @throws IOException in case of a problem
139 */
140 void tunnelProxy(HttpHost next, boolean secure, HttpParams params)
141 throws IOException;
142
143 /**
144 * Layers a new protocol on top of a {@link #tunnelTarget tunnelled}
145 * connection. This is typically used to create a TLS/SSL connection
146 * through a proxy.
147 * The route is the one previously passed to {@link #open open}.
148 * It is not guaranteed that the layered connection is
149 * {@link #isSecure secure}.
150 *
151 * @param context the context for layering on top of this connection
152 * @param params the parameters for layering on top of this connection
153 *
154 * @throws IOException in case of a problem
155 */
156 void layerProtocol(HttpContext context, HttpParams params)
157 throws IOException;
158
159 /**
160 * Marks this connection as being in a reusable communication state.
161 * The checkpoints for reuseable communication states (in the absence
162 * of pipelining) are before sending a request and after receiving
163 * the response in its entirety.
164 * The connection will automatically clear the checkpoint when
165 * used for communication. A call to this method indicates that
166 * the next checkpoint has been reached.
167 * <br/>
168 * A reusable communication state is necessary but not sufficient
169 * for the connection to be reused.
170 * A {@link #getRoute route} mismatch, the connection being closed,
171 * or other circumstances might prevent reuse.
172 */
173 void markReusable();
174
175 /**
176 * Marks this connection as not being in a reusable state.
177 * This can be used immediately before releasing this connection
178 * to prevent its reuse. Reasons for preventing reuse include
179 * error conditions and the evaluation of a
180 * {@link org.apache.http.ConnectionReuseStrategy reuse strategy}.
181 * <br/>
182 * <b>Note:</b>
183 * It is <i>not</i> necessary to call here before writing to
184 * or reading from this connection. Communication attempts will
185 * automatically unmark the state as non-reusable. It can then
186 * be switched back using {@link #markReusable markReusable}.
187 */
188 void unmarkReusable();
189
190 /**
191 * Indicates whether this connection is in a reusable communication state.
192 * See {@link #markReusable markReusable} and
193 * {@link #unmarkReusable unmarkReusable} for details.
194 *
195 * @return <code>true</code> if this connection is marked as being in
196 * a reusable communication state,
197 * <code>false</code> otherwise
198 */
199 boolean isMarkedReusable();
200
201 /**
202 * Assigns a state object to this connection. Connection managers may make
203 * use of the connection state when allocating persistent connections.
204 *
205 * @param state The state object
206 */
207 void setState(Object state);
208
209 /**
210 * Returns the state object associated with this connection.
211 *
212 * @return The state object
213 */
214 Object getState();
215
216 /**
217 * Sets the duration that this connection can remain idle before it is
218 * reused. The connection should not be used again if this time elapses. The
219 * idle duration must be reset after each request sent over this connection.
220 * The elapsed time starts counting when the connection is released, which
221 * is typically after the headers (and any response body, if present) is
222 * fully consumed.
223 */
224 void setIdleDuration(long duration, TimeUnit unit);
225
226 }