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 io.netty.channel;
17
18 import io.netty.buffer.ByteBuf;
19 import io.netty.buffer.ByteBufAllocator;
20
21
22 /**
23 * The {@link RecvByteBufAllocator} that always yields the same buffer
24 * size prediction. This predictor ignores the feed back from the I/O thread.
25 */
26 public class FixedRecvByteBufAllocator implements RecvByteBufAllocator {
27
28 private static final class HandleImpl implements Handle {
29
30 private final int bufferSize;
31
32 HandleImpl(int bufferSize) {
33 this.bufferSize = bufferSize;
34 }
35
36 @Override
37 public ByteBuf allocate(ByteBufAllocator alloc) {
38 return alloc.ioBuffer(bufferSize);
39 }
40
41 @Override
42 public int guess() {
43 return bufferSize;
44 }
45
46 @Override
47 public void record(int actualReadBytes) { }
48 }
49
50 private final Handle handle;
51
52 /**
53 * Creates a new predictor that always returns the same prediction of
54 * the specified buffer size.
55 */
56 public FixedRecvByteBufAllocator(int bufferSize) {
57 if (bufferSize <= 0) {
58 throw new IllegalArgumentException(
59 "bufferSize must greater than 0: " + bufferSize);
60 }
61
62 handle = new HandleImpl(bufferSize);
63 }
64
65 @Override
66 public Handle newHandle() {
67 return handle;
68 }
69 }