| /* |
| * 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.jclouds.glacier.blobstore.strategy.internal; |
| |
| import static com.google.common.base.Preconditions.checkNotNull; |
| import static java.lang.Math.sqrt; |
| |
| import javax.inject.Singleton; |
| |
| import org.jclouds.glacier.blobstore.strategy.PayloadSlice; |
| import org.jclouds.glacier.blobstore.strategy.SlicingStrategy; |
| import org.jclouds.glacier.util.ContentRange; |
| import org.jclouds.io.Payload; |
| import org.jclouds.io.PayloadSlicer; |
| |
| import com.google.inject.Inject; |
| import com.google.inject.name.Named; |
| |
| /** |
| * This implementation slice a payload based on the (part size)/(number of parts) ratio. This ratio may be overriden. |
| */ |
| @Singleton |
| public class BaseSlicingStrategy implements SlicingStrategy { |
| |
| public static final double DEFAULT_RATIO = 0.32; // (part size/number of parts) ratio |
| |
| @Inject(optional = true) |
| @Named("jclouds.mpu.part.ratio") |
| private final double ratio = DEFAULT_RATIO; |
| |
| private final PayloadSlicer slicer; |
| private Payload payload; |
| private volatile long partSizeInMB; |
| private volatile long total; |
| private volatile long copied; |
| private volatile int part; |
| |
| @Inject |
| public BaseSlicingStrategy(PayloadSlicer slicer) { |
| this.slicer = checkNotNull(slicer, "slicer"); |
| this.total = 0; |
| this.copied = 0; |
| this.partSizeInMB = 0; |
| this.part = 0; |
| } |
| |
| protected long calculatePartSize(long length) { |
| long lengthInMB = (long) (length / (1L << 20)) + 1; |
| double fpPartSizeInMB = sqrt(ratio * lengthInMB); //Get the part size which matches the given ratio |
| long partSizeInMB = Long.highestOneBit((long) fpPartSizeInMB - 1) << 1; |
| if (partSizeInMB < 1) return 1; |
| else if (partSizeInMB > MAX_PART_SIZE) return MAX_PART_SIZE; |
| return partSizeInMB; |
| } |
| |
| public long getRemaining() { |
| return total - copied; |
| } |
| |
| @Override |
| public void startSlicing(Payload payload) { |
| this.payload = checkNotNull(payload, "payload"); |
| this.copied = 0; |
| this.total = checkNotNull(payload.getContentMetadata().getContentLength(), "contentLength"); |
| this.partSizeInMB = calculatePartSize(total); |
| this.part = 0; |
| } |
| |
| @Override |
| public PayloadSlice nextSlice() { |
| checkNotNull(this.payload, "payload"); |
| long sliceLength = Math.min(getRemaining(), partSizeInMB << 20); |
| Payload slicedPayload = slicer.slice(payload, copied, sliceLength); |
| ContentRange range = ContentRange.build(copied, copied + sliceLength - 1); |
| copied += sliceLength; |
| part++; |
| return new PayloadSlice(slicedPayload, range, part); |
| } |
| |
| @Override |
| public boolean hasNext() { |
| return this.getRemaining() != 0; |
| } |
| |
| @Override |
| public long getPartSizeInMB() { |
| return partSizeInMB; |
| } |
| } |