1 /*
2  * Copyright (C) 2009 Google Inc.  All rights reserved.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.google.polo.wire;
18 
19 import java.io.IOException;
20 
21 import com.google.polo.exception.PoloException;
22 import com.google.polo.pairing.message.PoloMessage;
23 
24 /**
25  * Public interface for transport-layer implementations of the pairing
26  * protocol.
27  */
28 public interface PoloWireInterface {
29 
30   /**
31    * Returns the next message from the wire.
32    *
33    * @return a new PoloMessage instance
34    * @throws IOException  if an error occurred while reading
35    * @throws PoloException  if a protocol fault occurred
36    */
getNextMessage()37   public PoloMessage getNextMessage() throws IOException, PoloException;
38 
39   /**
40    * Returns the next message from the wire.
41    *
42    * @param type  the required message type to be read
43    * @return a new PoloMessage instance
44    * @throws IOException  if an error occurred while reading
45    * @throws PoloException  if the next message did not match the requested
46    *                        type.
47    */
getNextMessage(PoloMessage.PoloMessageType type)48   public PoloMessage getNextMessage(PoloMessage.PoloMessageType type)
49       throws IOException, PoloException;
50 
51   /**
52    * Send a normal message out on the wire.
53    *
54    * @param message  the message to send
55    * @throws IOException  if an error occurred while sending
56    * @throws PoloException  if the message was not well formed
57    */
sendMessage(PoloMessage message)58   public void sendMessage(PoloMessage message)
59       throws IOException, PoloException;
60 
61   /**
62    * Send an error message out on the wire, based on an exception.
63    *
64    * @param e  the exception causing the error
65    * @throws IOException  if an error occurred while sending
66    */
sendErrorMessage(Exception e)67   public void sendErrorMessage(Exception e) throws IOException;
68 
69 }
70