001/**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.activemq.transport;
018
019import java.io.IOException;
020import java.net.URI;
021import org.apache.activemq.Service;
022
023/**
024 * Represents the client side of a transport allowing messages to be sent
025 * synchronously, asynchronously and consumed.
026 */
027public interface Transport extends Service {
028
029    /**
030     * A one way asynchronous send
031     *
032     * @param command
033     * @throws IOException
034     */
035    void oneway(Object command) throws IOException;
036
037    /**
038     * An asynchronous request response where the Receipt will be returned in
039     * the future. If responseCallback is not null, then it will be called when
040     * the response has been completed.
041     *
042     * @param command
043     * @param responseCallback TODO
044     * @return the FutureResponse
045     * @throws IOException
046     */
047    FutureResponse asyncRequest(Object command, ResponseCallback responseCallback) throws IOException;
048
049    /**
050     * A synchronous request response
051     *
052     * @param command
053     * @return the response
054     * @throws IOException
055     */
056    Object request(Object command) throws IOException;
057
058    /**
059     * A synchronous request response
060     *
061     * @param command
062     * @param timeout
063     * @return the repsonse or null if timeout
064     * @throws IOException
065     */
066    Object request(Object command, int timeout) throws IOException;
067
068    /**
069     * Returns the current transport listener
070     *
071     * @return
072     */
073    TransportListener getTransportListener();
074
075    /**
076     * Registers an inbound command listener
077     *
078     * @param commandListener
079     */
080    void setTransportListener(TransportListener commandListener);
081
082    /**
083     * @param target
084     * @return the target
085     */
086    <T> T narrow(Class<T> target);
087
088    /**
089     * @return the remote address for this connection
090     */
091    String getRemoteAddress();
092
093    /**
094     * Indicates if the transport can handle faults
095     *
096     * @return true if fault tolerant
097     */
098    boolean isFaultTolerant();
099
100    /**
101     * @return true if the transport is disposed
102     */
103    boolean isDisposed();
104
105    /**
106     * @return true if the transport is connected
107     */
108    boolean isConnected();
109
110    /**
111     * @return true if reconnect is supported
112     */
113    boolean isReconnectSupported();
114
115    /**
116     * @return true if updating uris is supported
117     */
118    boolean isUpdateURIsSupported();
119    /**
120     * reconnect to another location
121     * @param uri
122     * @throws IOException on failure of if not supported
123     */
124    void reconnect(URI uri) throws IOException;
125
126    /**
127     * Provide a list of available alternative locations
128     * @param rebalance
129     * @param uris
130     * @throws IOException
131     */
132    void updateURIs(boolean rebalance,URI[] uris) throws IOException;
133
134    /**
135     * Returns a counter which gets incremented as data is read from the transport.
136     * It should only be used to determine if there is progress being made in reading the next command from the transport.
137     * The value may wrap into the negative numbers.
138     *
139     * @return a counter which gets incremented as data is read from the transport.
140     */
141    int getReceiveCounter();
142}