/lib/src/org/apache/http/conn/OperatedClientConnection.java

  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
 28package org.apache.http.conn;
 29
 30import java.io.IOException;
 31import java.net.Socket;
 32
 33import org.apache.http.HttpClientConnection;
 34import org.apache.http.HttpHost;
 35import org.apache.http.HttpInetConnection;
 36import org.apache.http.params.HttpParams;
 37
 38/**
 39 * A client-side connection that relies on outside logic to connect sockets to the
 40 * appropriate hosts. It can be operated directly by an application, or through an
 41 * {@link ClientConnectionOperator operator}.
 42 *
 43 * @since 4.0
 44 */
 45public interface OperatedClientConnection extends HttpClientConnection, HttpInetConnection {
 46
 47    /**
 48     * Obtains the target host for this connection.
 49     * If the connection is to a proxy but not tunnelled, this is
 50     * the proxy. If the connection is tunnelled through a proxy,
 51     * this is the target of the tunnel.
 52     * <br/>
 53     * The return value is well-defined only while the connection is open.
 54     * It may change even while the connection is open,
 55     * because of an {@link #update update}.
 56     *
 57     * @return  the host to which this connection is opened
 58     */
 59    HttpHost getTargetHost();
 60
 61    /**
 62     * Indicates whether this connection is secure.
 63     * The return value is well-defined only while the connection is open.
 64     * It may change even while the connection is open,
 65     * because of an {@link #update update}.
 66     *
 67     * @return  <code>true</code> if this connection is secure,
 68     *          <code>false</code> otherwise
 69     */
 70    boolean isSecure();
 71
 72    /**
 73     * Obtains the socket for this connection.
 74     * The return value is well-defined only while the connection is open.
 75     * It may change even while the connection is open,
 76     * because of an {@link #update update}.
 77     *
 78     * @return  the socket for communicating with the
 79     *          {@link #getTargetHost target host}
 80     */
 81    Socket getSocket();
 82
 83    /**
 84     * Signals that this connection is in the process of being open.
 85     * <p>
 86     * By calling this method, the connection can be re-initialized
 87     * with a new Socket instance before {@link #openCompleted} is called.
 88     * This enabled the connection to close that socket if
 89     * {@link org.apache.http.HttpConnection#shutdown shutdown}
 90     * is called before it is fully open. Closing an unconnected socket
 91     * will interrupt a thread that is blocked on the connect.
 92     * Otherwise, that thread will either time out on the connect,
 93     * or it returns successfully and then opens this connection
 94     * which was just shut down.
 95     * <p>
 96     * This method can be called multiple times if the connection
 97     * is layered over another protocol. <b>Note:</b> This method
 98     * will <i>not</i> close the previously used socket. It is
 99     * the caller's responsibility to close that socket if it is
100     * no longer required.
101     * <p>
102     * The caller must invoke {@link #openCompleted} in order to complete
103     * the process.
104     *
105     * @param sock      the unconnected socket which is about to
106     *                  be connected.
107     * @param target    the target host of this connection
108     */
109    void opening(Socket sock, HttpHost target)
110        throws IOException;
111
112    /**
113     * Signals that the connection has been successfully open.
114     * An attempt to call this method on an open connection will cause
115     * an exception.
116     *
117     * @param secure    <code>true</code> if this connection is secure, for
118     *                  example if an <code>SSLSocket</code> is used, or
119     *                  <code>false</code> if it is not secure
120     * @param params    parameters for this connection. The parameters will
121     *                  be used when creating dependent objects, for example
122     *                  to determine buffer sizes.
123     */
124    void openCompleted(boolean secure, HttpParams params)
125        throws IOException;
126
127    /**
128     * Updates this connection.
129     * A connection can be updated only while it is open.
130     * Updates are used for example when a tunnel has been established,
131     * or when a TLS/SSL connection has been layered on top of a plain
132     * socket connection.
133     * <br/>
134     * <b>Note:</b> Updating the connection will <i>not</i> close the
135     * previously used socket. It is the caller's responsibility to close
136     * that socket if it is no longer required.
137     *
138     * @param sock      the new socket for communicating with the target host,
139     *                  or <code>null</code> to continue using the old socket.
140     *                  If <code>null</code> is passed, helper objects that
141     *                  depend on the socket should be re-used. In that case,
142     *                  some changes in the parameters will not take effect.
143     * @param target    the new target host of this connection
144     * @param secure    <code>true</code> if this connection is now secure,
145     *                  <code>false</code> if it is not secure
146     * @param params    new parameters for this connection
147     */
148    void update(Socket sock, HttpHost target,
149                boolean secure, HttpParams params)
150        throws IOException;
151
152}