1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 *
19 */
20 package org.apache.mina.core.future;
21
22
23 /**
24 * An {@link IoFuture} for asynchronous write requests.
25 *
26 * <h3>Example</h3>
27 * <pre>
28 * IoSession session = ...;
29 * WriteFuture future = session.write(...);
30 * // Wait until the message is completely written out to the O/S buffer.
31 * future.join();
32 * if( future.isWritten() )
33 * {
34 * // The message has been written successfully.
35 * }
36 * else
37 * {
38 * // The messsage couldn't be written out completely for some reason.
39 * // (e.g. Connection is closed)
40 * }
41 * </pre>
42 *
43 * @author The Apache MINA Project (dev@mina.apache.org)
44 */
45 public interface WriteFuture extends IoFuture {
46 /**
47 * Returns <tt>true</tt> if the write operation is finished successfully.
48 */
49 boolean isWritten();
50
51 /**
52 * Returns the cause of the write failure if and only if the write
53 * operation has failed due to an {@link Exception}. Otherwise,
54 * <tt>null</tt> is returned.
55 */
56 Throwable getException();
57
58 /**
59 * Sets the message is written, and notifies all threads waiting for
60 * this future. This method is invoked by MINA internally. Please do
61 * not call this method directly.
62 */
63 void setWritten();
64
65 /**
66 * Sets the cause of the write failure, and notifies all threads waiting
67 * for this future. This method is invoked by MINA internally. Please
68 * do not call this method directly.
69 */
70 void setException(Throwable cause);
71
72 /**
73 * Wait for the asynchronous operation to complete.
74 * The attached listeners will be notified when the operation is
75 * completed.
76 *
77 * @return the created {@link WriteFuture}
78 * @throws InterruptedException
79 */
80 WriteFuture await() throws InterruptedException;
81
82 /**
83 * {@inheritDoc}
84 */
85 WriteFuture awaitUninterruptibly();
86
87 /**
88 * {@inheritDoc}
89 */
90 WriteFuture addListener(IoFutureListener<?> listener);
91
92 /**
93 * {@inheritDoc}
94 */
95 WriteFuture removeListener(IoFutureListener<?> listener);
96 }