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 * An {@link IoFuture} for asynchronous write requests.
24 *
25 * <h3>Example</h3>
26 * <pre>
27 * IoSession session = ...;
28 * WriteFuture future = session.write(...);
29 * // Wait until the message is completely written out to the O/S buffer.
30 * future.join();
31 * if( future.isWritten() )
32 * {
33 * // The message has been written successfully.
34 * }
35 * else
36 * {
37 * // The messsage couldn't be written out completely for some reason.
38 * // (e.g. Connection is closed)
39 * }
40 * </pre>
41 *
42 * @author <a href="http://mina.apache.org">Apache MINA Project</a>
43 */
44 public interface WriteFuture extends IoFuture {
45 /**
46 * Returns <tt>true</tt> if the write operation is finished successfully.
47 */
48 boolean isWritten();
49
50 /**
51 * Returns the cause of the write failure if and only if the write
52 * operation has failed due to an {@link Exception}. Otherwise,
53 * <tt>null</tt> is returned.
54 */
55 Throwable getException();
56
57 /**
58 * Sets the message is written, and notifies all threads waiting for
59 * this future. This method is invoked by MINA internally. Please do
60 * not call this method directly.
61 */
62 void setWritten();
63
64 /**
65 * Sets the cause of the write failure, and notifies all threads waiting
66 * for this future. This method is invoked by MINA internally. Please
67 * do not call this method directly.
68 */
69 void setException(Throwable cause);
70
71 /**
72 * Wait for the asynchronous operation to complete.
73 * The attached listeners will be notified when the operation is
74 * completed.
75 *
76 * @return the created {@link WriteFuture}
77 * @throws InterruptedException
78 */
79 WriteFuture await() throws InterruptedException;
80
81 /**
82 * {@inheritDoc}
83 */
84 WriteFuture awaitUninterruptibly();
85
86 /**
87 * {@inheritDoc}
88 */
89 WriteFuture addListener(IoFutureListener<?> listener);
90
91 /**
92 * {@inheritDoc}
93 */
94 WriteFuture removeListener(IoFutureListener<?> listener);
95 }