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/**
* 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.server.blockmanagement;
import io.prestosql.hadoop.$internal.com.google.common.base.Preconditions;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.hdfs.protocol.Block;
import org.apache.hadoop.hdfs.protocol.BlockType;
/**
* Subclass of {@link BlockInfo}, used for a block with replication scheme.
*/
@InterfaceAudience.Private
public class BlockInfoContiguous extends BlockInfo {
public BlockInfoContiguous(short size) {
super(size);
}
public BlockInfoContiguous(Block blk, short size) {
super(blk, size);
}
/**
* Ensure that there is enough space to include num more storages.
* @return first free storage index.
*/
private int ensureCapacity(int num) {
assert this.storages != null : "BlockInfo is not initialized";
int last = numNodes();
if (storages.length >= (last+num)) {
return last;
}
/* Not enough space left. Create a new array. Should normally
* happen only when replication is manually increased by the user. */
DatanodeStorageInfo[] old = storages;
storages = new DatanodeStorageInfo[(last+num)];
System.arraycopy(old, 0, storages, 0, last);
return last;
}
@Override
boolean addStorage(DatanodeStorageInfo storage, Block reportedBlock) {
Preconditions.checkArgument(this.getBlockId() == reportedBlock.getBlockId(),
"reported blk_%s is different from stored blk_%s",
reportedBlock.getBlockId(), this.getBlockId());
// find the last null node
int lastNode = ensureCapacity(1);
setStorageInfo(lastNode, storage);
return true;
}
@Override
boolean removeStorage(DatanodeStorageInfo storage) {
int dnIndex = findStorageInfo(storage);
if (dnIndex < 0) { // the node is not found
return false;
}
// find the last not null node
int lastNode = numNodes()-1;
// replace current node entry by the lastNode one
setStorageInfo(dnIndex, getStorageInfo(lastNode));
// set the last entry to null
setStorageInfo(lastNode, null);
return true;
}
@Override
public int numNodes() {
assert this.storages != null : "BlockInfo is not initialized";
for (int idx = getCapacity()-1; idx >= 0; idx--) {
if (getDatanode(idx) != null) {
return idx + 1;
}
}
return 0;
}
@Override
public final boolean isStriped() {
return false;
}
@Override
public BlockType getBlockType() {
return BlockType.CONTIGUOUS;
}
@Override
final boolean hasNoStorage() {
return getStorageInfo(0) == null;
}
}