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.nio.reactor;
29
30 import java.net.SocketAddress;
31
32 /**
33 * ConnectingIOReactor represents an I/O reactor capable of establishing
34 * connections to remote hosts.
35 *
36 * @since 4.0
37 */
38 public interface ConnectingIOReactor extends IOReactor {
39
40 /**
41 * Requests a connection to a remote host.
42 * <p>
43 * Opening a connection to a remote host usually tends to be a time
44 * consuming process and may take a while to complete. One can monitor and
45 * control the process of session initialization by means of the
46 * {@link SessionRequest} interface.
47 * <p>
48 * There are several parameters one can use to exert a greater control over
49 * the process of session initialization:
50 * <p>
51 * A non-null local socket address parameter can be used to bind the socket
52 * to a specific local address.
53 * <p>
54 * An attachment object can added to the new session's context upon
55 * initialization. This object can be used to pass an initial processing
56 * state to the protocol handler.
57 * <p>
58 * It is often desirable to be able to react to the completion of a session
59 * request asynchronously without having to wait for it, blocking the
60 * current thread of execution. One can optionally provide an implementation
61 * {@link SessionRequestCallback} instance to get notified of events related
62 * to session requests, such as request completion, cancellation, failure or
63 * timeout.
64 *
65 * @param remoteAddress the socket address of the remote host.
66 * @param localAddress the local socket address. Can be <code>null</code>,
67 * in which can the default local address and a random port will be used.
68 * @param attachment the attachment object. Can be <code>null</code>.
69 * @param callback interface. Can be <code>null</code>.
70 * @return session request object.
71 */
72 SessionRequest connect(
73 SocketAddress remoteAddress,
74 SocketAddress localAddress,
75 Object attachment,
76 SessionRequestCallback callback);
77
78 }