1 /*
2  * Copyright 2017 The Android Open Source Project
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 package org.conscrypt;
17 
18 import io.netty.buffer.ByteBuf;
19 import io.netty.buffer.ByteBufAllocator;
20 import io.netty.buffer.PooledByteBufAllocator;
21 import java.nio.ByteBuffer;
22 
23 /**
24  * A {@link BufferAllocator} that is backed by a Netty buffer pool.
25  */
26 final class NettyBufferAllocator extends BufferAllocator {
27     private static final ByteBufAllocator alloc = PooledByteBufAllocator.DEFAULT;
28     private static final NettyBufferAllocator instance = new NettyBufferAllocator();
29 
getInstance()30     static NettyBufferAllocator getInstance() {
31         return instance;
32     }
33 
NettyBufferAllocator()34     private NettyBufferAllocator() {}
35 
36     @Override
allocateDirectBuffer(int capacity)37     public AllocatedBuffer allocateDirectBuffer(int capacity) {
38         return new ByteBufAdapter(alloc.directBuffer(capacity));
39     }
40 
41     private static final class ByteBufAdapter extends AllocatedBuffer {
42         private final ByteBuf nettyBuffer;
43         private final ByteBuffer buffer;
44 
ByteBufAdapter(ByteBuf nettyBuffer)45         private ByteBufAdapter(ByteBuf nettyBuffer) {
46             this.nettyBuffer = nettyBuffer;
47             this.buffer = nettyBuffer.nioBuffer(0, nettyBuffer.capacity());
48         }
49 
50         @Override
nioBuffer()51         public ByteBuffer nioBuffer() {
52             return buffer;
53         }
54 
55         @Override
retain()56         public AllocatedBuffer retain() {
57             nettyBuffer.retain();
58             return this;
59         }
60 
61         @Override
release()62         public AllocatedBuffer release() {
63             nettyBuffer.release();
64             return this;
65         }
66     }
67 }
68