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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.scheme;
29  
30  import java.io.IOException;
31  import java.net.InetSocketAddress;
32  import java.net.Socket;
33  import java.net.UnknownHostException;
34  
35  import org.apache.http.HttpHost;
36  import org.apache.http.conn.ConnectTimeoutException;
37  import org.apache.http.conn.HttpInetSocketAddress;
38  import org.apache.http.params.HttpParams;
39  
40  /**
41   * A factory for creating, initializing and connecting sockets. The factory encapsulates the logic
42   * for establishing a socket connection.
43   *
44   * @since 4.1
45   */
46  public interface SchemeSocketFactory {
47  
48      /**
49       * Creates a new, unconnected socket. The socket should subsequently be passed to
50       * {@link #connectSocket(Socket, InetSocketAddress, InetSocketAddress, HttpParams)}.
51       *
52       * @param params    Optional {@link HttpParams parameters}. In most cases these parameters
53       *                  will not be required and will have no effect, as usually socket
54       *                  initialization should take place in the
55       *                  {@link #connectSocket(Socket, InetSocketAddress, InetSocketAddress, HttpParams)}
56       *                  method. However, in rare cases one may want to pass additional parameters
57       *                  to this method in order to create a customized {@link Socket} instance,
58       *                  for instance bound to a SOCKS proxy server.
59       *
60       * @return  a new socket
61       *
62       * @throws IOException if an I/O error occurs while creating the socket
63       */
64      Socket createSocket(HttpParams params) throws IOException;
65  
66      /**
67       * Connects a socket to the target host with the given remote address.
68       * <p/>
69       * Please note that {@link HttpInetSocketAddress} class should be used in order to pass
70       * the target remote address along with the original {@link HttpHost} value used to resolve
71       * the address. The use of {@link HttpInetSocketAddress} can also ensure that no reverse
72       * DNS lookup will be performed if the target remote address was specified as an IP address.
73       *
74       * @param sock      the socket to connect, as obtained from
75       *                  {@link #createSocket(HttpParams) createSocket}.
76       *                  <code>null</code> indicates that a new socket
77       *                  should be created and connected.
78       * @param remoteAddress the remote address to connect to.
79       * @param localAddress the local address to bind the socket to, or
80       *                  <code>null</code> for any
81       * @param params    additional {@link HttpParams parameters} for connecting
82       *
83       * @return  the connected socket. The returned object may be different
84       *          from the <code>sock</code> argument if this factory supports
85       *          a layered protocol.
86       *
87       * @throws IOException if an I/O error occurs
88       * @throws UnknownHostException if the IP address of the target host
89       *          can not be determined
90       * @throws ConnectTimeoutException if the socket cannot be connected
91       *          within the time limit defined in the <code>params</code>
92       *
93       * @see HttpInetSocketAddress
94       */
95      Socket connectSocket(
96          Socket sock,
97          InetSocketAddress remoteAddress,
98          InetSocketAddress localAddress,
99          HttpParams params) throws IOException, UnknownHostException, ConnectTimeoutException;
100 
101     /**
102      * Checks whether a socket provides a secure connection. The socket must be
103      * {@link #connectSocket(Socket, InetSocketAddress, InetSocketAddress, HttpParams) connected}
104      * by this factory. The factory will <i>not</i> perform I/O operations in this method.
105      * <p>
106      * As a rule of thumb, plain sockets are not secure and TLS/SSL sockets are secure. However,
107      * there may be application specific deviations. For example, a plain socket to a host in the
108      * same intranet ("trusted zone") could be considered secure. On the other hand, a TLS/SSL
109      * socket could be considered insecure based on the cipher suite chosen for the connection.
110      *
111      * @param sock      the connected socket to check
112      *
113      * @return  <code>true</code> if the connection of the socket
114      *          should be considered secure, or
115      *          <code>false</code> if it should not
116      *
117      * @throws IllegalArgumentException
118      *  if the argument is invalid, for example because it is
119      *  not a connected socket or was created by a different
120      *  socket factory.
121      *  Note that socket factories are <i>not</i> required to
122      *  check these conditions, they may simply return a default
123      *  value when called with an invalid socket argument.
124      */
125     boolean isSecure(Socket sock) throws IllegalArgumentException;
126 
127 }