- /**
- * 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.hdfs.protocol;
- /**
- * This class provides an interface for accessing list of blocks that
- * has been implemented as long[].
- * This class is usefull for block report. Rather than send block reports
- * as a Block[] we can send it as a long[].
- *
- */
- public class BlockListAsLongs {
- /**
- * A block as 3 longs
- * block-id and block length and generation stamp
- */
- private static final int LONGS_PER_BLOCK = 3;
- private static int index2BlockId(int index) {
- return index*LONGS_PER_BLOCK;
- }
- private static int index2BlockLen(int index) {
- return (index*LONGS_PER_BLOCK) + 1;
- }
- private static int index2BlockGenStamp(int index) {
- return (index*LONGS_PER_BLOCK) + 2;
- }
- private long[] blockList;
- /**
- * Converting a block[] to a long[]
- * @param blockArray - the input array block[]
- * @return the output array of long[]
- */
- public static long[] convertToArrayLongs(final Block[] blockArray) {
- long[] blocksAsLongs = new long[blockArray.length * LONGS_PER_BLOCK];
- BlockListAsLongs bl = new BlockListAsLongs(blocksAsLongs);
- assert bl.getNumberOfBlocks() == blockArray.length;
- for (int i = 0; i < blockArray.length; i++) {
- bl.setBlock(i, blockArray[i]);
- }
- return blocksAsLongs;
- }
- /**
- * Constructor
- * @param iBlockList - BlockListALongs create from this long[] parameter
- */
- public BlockListAsLongs(final long[] iBlockList) {
- if (iBlockList == null) {
- blockList = new long[0];
- } else {
- if (iBlockList.length%LONGS_PER_BLOCK != 0) {
- // must be multiple of LONGS_PER_BLOCK
- throw new IllegalArgumentException();
- }
- blockList = iBlockList;
- }
- }
- /**
- * The number of blocks
- * @return - the number of blocks
- */
- public int getNumberOfBlocks() {
- return blockList.length/LONGS_PER_BLOCK;
- }
- /**
- * The block-id of the indexTh block
- * @param index - the block whose block-id is desired
- * @return the block-id
- */
- public long getBlockId(final int index) {
- return blockList[index2BlockId(index)];
- }
- /**
- * The block-len of the indexTh block
- * @param index - the block whose block-len is desired
- * @return - the block-len
- */
- public long getBlockLen(final int index) {
- return blockList[index2BlockLen(index)];
- }
- /**
- * The generation stamp of the indexTh block
- * @param index - the block whose block-len is desired
- * @return - the generation stamp
- */
- public long getBlockGenStamp(final int index) {
- return blockList[index2BlockGenStamp(index)];
- }
- /**
- * Set the indexTh block
- * @param index - the index of the block to set
- * @param b - the block is set to the value of the this block
- */
- void setBlock(final int index, final Block b) {
- blockList[index2BlockId(index)] = b.getBlockId();
- blockList[index2BlockLen(index)] = b.getNumBytes();
- blockList[index2BlockGenStamp(index)] = b.getGenerationStamp();
- }
- }