1 /*
2 * Copyright 2012 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. 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, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package org.jboss.netty.channel.socket.nio;
17
18 import java.nio.ByteBuffer;
19 import java.nio.channels.WritableByteChannel;
20
21 import org.jboss.netty.channel.Channel;
22 import org.jboss.netty.channel.ChannelConfig;
23
24 /**
25 * Special {@link ChannelConfig} sub-type which offers extra methods which are useful for NIO.
26 *
27 */
28 public interface NioChannelConfig extends ChannelConfig {
29
30 /**
31 * Returns the high water mark of the write buffer. If the number of bytes
32 * queued in the write buffer exceeds this value, {@link Channel#isWritable()}
33 * will start to return {@code false}.
34 */
35 int getWriteBufferHighWaterMark();
36
37 /**
38 * Sets the high water mark of the write buffer. If the number of bytes
39 * queued in the write buffer exceeds this value, {@link Channel#isWritable()}
40 * will start to return {@code false}.
41 */
42 void setWriteBufferHighWaterMark(int writeBufferHighWaterMark);
43
44 /**
45 * Returns the low water mark of the write buffer. Once the number of bytes
46 * queued in the write buffer exceeded the
47 * {@linkplain #setWriteBufferHighWaterMark(int) high water mark} and then
48 * dropped down below this value, {@link Channel#isWritable()} will start to return
49 * {@code true} again.
50 */
51 int getWriteBufferLowWaterMark();
52
53 /**
54 * Sets the low water mark of the write buffer. Once the number of bytes
55 * queued in the write buffer exceeded the
56 * {@linkplain #setWriteBufferHighWaterMark(int) high water mark} and then
57 * dropped down below this value, {@link Channel#isWritable()} will start toreturn
58 * {@code true} again.
59 */
60 void setWriteBufferLowWaterMark(int writeBufferLowWaterMark);
61
62 /**
63 * Returns the maximum loop count for a write operation until
64 * {@link WritableByteChannel#write(ByteBuffer)} returns a non-zero value.
65 * It is similar to what a spin lock is used for in concurrency programming.
66 * It improves memory utilization and write throughput depending on
67 * the platform that JVM runs on. The default value is {@code 16}.
68 */
69 int getWriteSpinCount();
70
71 /**
72 * Sets the maximum loop count for a write operation until
73 * {@link WritableByteChannel#write(ByteBuffer)} returns a non-zero value.
74 * It is similar to what a spin lock is used for in concurrency programming.
75 * It improves memory utilization and write throughput depending on
76 * the platform that JVM runs on. The default value is {@code 16}.
77 *
78 * @throws IllegalArgumentException
79 * if the specified value is {@code 0} or less than {@code 0}
80 */
81 void setWriteSpinCount(int writeSpinCount);
82 }