org.apache.hadoop.hdfs.server.datanode.ReplicaInPipeline Maven / Gradle / Ivy
/**
* 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.datanode;
import java.io.IOException;
import java.io.OutputStream;
import java.util.concurrent.TimeUnit;
import org.apache.hadoop.hdfs.server.datanode.fsdataset.ReplicaOutputStreams;
import org.apache.hadoop.util.DataChecksum;
/**
* This defines the interface of a replica in Pipeline that's being written to
*/
public interface ReplicaInPipeline extends Replica {
/**
* Set the number of bytes received
* @param bytesReceived number of bytes received
*/
void setNumBytes(long bytesReceived);
/**
* Get the number of bytes acked
* @return the number of bytes acked
*/
long getBytesAcked();
/**
* Set the number bytes that have acked
* @param bytesAcked number bytes acked
*/
void setBytesAcked(long bytesAcked);
/**
* Release any disk space reserved for this replica.
*/
public void releaseAllBytesReserved();
/**
* store the checksum for the last chunk along with the data length
* @param dataLength number of bytes on disk
* @param lastChecksum - checksum bytes for the last chunk
*/
public void setLastChecksumAndDataLen(long dataLength, byte[] lastChecksum);
/**
* gets the last chunk checksum and the length of the block corresponding
* to that checksum
*/
public ChunkChecksum getLastChecksumAndDataLen();
/**
* Create output streams for writing to this replica,
* one for block file and one for CRC file
*
* @param isCreate if it is for creation
* @param requestedChecksum the checksum the writer would prefer to use
* @return output streams for writing
* @throws IOException if any error occurs
*/
public ReplicaOutputStreams createStreams(boolean isCreate,
DataChecksum requestedChecksum) throws IOException;
/**
* Create an output stream to write restart metadata in case of datanode
* shutting down for quick restart.
*
* @return output stream for writing.
* @throws IOException if any error occurs
*/
public OutputStream createRestartMetaStream() throws IOException;
ReplicaInfo getReplicaInfo();
/**
* Set the thread that is writing to this replica
* @param writer a thread writing to this replica
*/
void setWriter(Thread writer);
void interruptThread();
/**
* Attempt to set the writer to a new value.
*/
boolean attemptToSetWriter(Thread prevWriter, Thread newWriter);
/**
* Interrupt the writing thread and wait until it dies.
* @throws IOException the waiting is interrupted
*/
void stopWriter(long xceiverStopTimeout) throws IOException;
/**
* Causes the current thread to wait until a minimum length is reached, the
* thread is interrupted, or the specified waiting time elapses.
*
* @param minLength The minimum length to achieve
* @param time the maximum time to wait
* @param unit the time unit of the time argument
* @throws IOException if the current thread is interrupted or the minimum
* length is not achieved within the time allowed.
*/
void waitForMinLength(long minLength, long time, TimeUnit unit)
throws IOException;
}