LocatedBlock.java
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上传日期:2018-01-08
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文件大小:4k
- /**
- * 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;
- import org.apache.hadoop.io.*;
- import java.io.*;
- /****************************************************
- * A LocatedBlock is a pair of Block, DatanodeInfo[]
- * objects. It tells where to find a Block.
- *
- ****************************************************/
- public class LocatedBlock implements Writable {
- static { // register a ctor
- WritableFactories.setFactory
- (LocatedBlock.class,
- new WritableFactory() {
- public Writable newInstance() { return new LocatedBlock(); }
- });
- }
- private Block b;
- private long offset; // offset of the first byte of the block in the file
- private DatanodeInfo[] locs;
- // corrupt flag is true if all of the replicas of a block are corrupt.
- // else false. If block has few corrupt replicas, they are filtered and
- // their locations are not part of this object
- private boolean corrupt;
- /**
- */
- public LocatedBlock() {
- this(new Block(), new DatanodeInfo[0], 0L, false);
- }
- /**
- */
- public LocatedBlock(Block b, DatanodeInfo[] locs) {
- this(b, locs, -1, false); // startOffset is unknown
- }
- /**
- */
- public LocatedBlock(Block b, DatanodeInfo[] locs, long startOffset) {
- this(b, locs, startOffset, false);
- }
- /**
- */
- public LocatedBlock(Block b, DatanodeInfo[] locs, long startOffset,
- boolean corrupt) {
- this.b = b;
- this.offset = startOffset;
- this.corrupt = corrupt;
- if (locs==null) {
- this.locs = new DatanodeInfo[0];
- } else {
- this.locs = locs;
- }
- }
- /**
- */
- public Block getBlock() {
- return b;
- }
- /**
- */
- public DatanodeInfo[] getLocations() {
- return locs;
- }
-
- public long getStartOffset() {
- return offset;
- }
-
- public long getBlockSize() {
- return b.getNumBytes();
- }
- void setStartOffset(long value) {
- this.offset = value;
- }
- void setCorrupt(boolean corrupt) {
- this.corrupt = corrupt;
- }
-
- public boolean isCorrupt() {
- return this.corrupt;
- }
- ///////////////////////////////////////////
- // Writable
- ///////////////////////////////////////////
- public void write(DataOutput out) throws IOException {
- out.writeBoolean(corrupt);
- out.writeLong(offset);
- b.write(out);
- out.writeInt(locs.length);
- for (int i = 0; i < locs.length; i++) {
- locs[i].write(out);
- }
- }
- public void readFields(DataInput in) throws IOException {
- this.corrupt = in.readBoolean();
- offset = in.readLong();
- this.b = new Block();
- b.readFields(in);
- int count = in.readInt();
- this.locs = new DatanodeInfo[count];
- for (int i = 0; i < locs.length; i++) {
- locs[i] = new DatanodeInfo();
- locs[i].readFields(in);
- }
- }
- }