| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.hadoop.io.erasurecode; |
| |
| |
| import java.nio.ByteBuffer; |
| |
| /** |
| * An abstract buffer allocator used for test. |
| */ |
| public abstract class BufferAllocator { |
| private boolean usingDirect = false; |
| |
| public BufferAllocator(boolean usingDirect) { |
| this.usingDirect = usingDirect; |
| } |
| |
| protected boolean isUsingDirect() { |
| return usingDirect; |
| } |
| |
| /** |
| * Allocate and return a ByteBuffer of specified length. |
| * @param bufferLen |
| * @return |
| */ |
| public abstract ByteBuffer allocate(int bufferLen); |
| |
| /** |
| * A simple buffer allocator that just uses ByteBuffer's |
| * allocate/allocateDirect API. |
| */ |
| public static class SimpleBufferAllocator extends BufferAllocator { |
| |
| public SimpleBufferAllocator(boolean usingDirect) { |
| super(usingDirect); |
| } |
| |
| @Override |
| public ByteBuffer allocate(int bufferLen) { |
| return isUsingDirect() ? ByteBuffer.allocateDirect(bufferLen) : |
| ByteBuffer.allocate(bufferLen); |
| } |
| } |
| |
| /** |
| * A buffer allocator that allocates a buffer from an existing large buffer by |
| * slice calling, but if no available space just degrades as |
| * SimpleBufferAllocator. So please ensure enough space for it. |
| */ |
| public static class SlicedBufferAllocator extends BufferAllocator { |
| private ByteBuffer overallBuffer; |
| |
| public SlicedBufferAllocator(boolean usingDirect, int totalBufferLen) { |
| super(usingDirect); |
| overallBuffer = isUsingDirect() ? |
| ByteBuffer.allocateDirect(totalBufferLen) : |
| ByteBuffer.allocate(totalBufferLen); |
| } |
| |
| @Override |
| public ByteBuffer allocate(int bufferLen) { |
| if (bufferLen > overallBuffer.capacity() - overallBuffer.position()) { |
| // If no available space for the requested length, then allocate new |
| return isUsingDirect() ? ByteBuffer.allocateDirect(bufferLen) : |
| ByteBuffer.allocate(bufferLen); |
| } |
| |
| overallBuffer.limit(overallBuffer.position() + bufferLen); |
| ByteBuffer result = overallBuffer.slice(); |
| overallBuffer.position(overallBuffer.position() + bufferLen); |
| return result; |
| } |
| } |
| |
| } |