org.apache.hadoop.hbase.client.BufferedMutator 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.hbase.client;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.classification.InterfaceStability;
import java.io.Closeable;
import java.io.IOException;
import java.util.List;
/**
* Used to communicate with a single HBase table similar to {@link Table} but meant for
* batched, asynchronous puts. Obtain an instance from a {@link Connection} and call
* {@link #close()} afterwards. Customizations can be applied to the {@code BufferedMutator} via
* the {@link BufferedMutatorParams}.
*
*
* Exception handling with asynchronously via the {@link BufferedMutator.ExceptionListener}.
* The default implementation is to throw the exception upon receipt. This behavior can be
* overridden with a custom implementation, provided as a parameter with
* {@link BufferedMutatorParams#listener(BufferedMutator.ExceptionListener)}.
*
* Map/Reduce jobs are good use cases for using {@code BufferedMutator}. Map/reduce jobs
* benefit from batching, but have no natural flush point. {@code BufferedMutator} receives the
* puts from the M/R job and will batch puts based on some heuristic, such as the accumulated size
* of the puts, and submit batches of puts asynchronously so that the M/R logic can continue
* without interruption.
*
*
* {@code BufferedMutator} can also be used on more exotic circumstances. Map/Reduce batch jobs
* will have a single {@code BufferedMutator} per thread. A single {@code BufferedMutator} can
* also be effectively used in high volume online systems to batch puts, with the caveat that
* extreme circumstances, such as JVM or machine failure, may cause some data loss.
*
* NOTE: This class replaces the functionality that used to be available via
* {@link HTableInterface#setAutoFlush(boolean)} set to {@code false}.
*
*
* See also the {@code BufferedMutatorExample} in the hbase-examples module.
* @see ConnectionFactory
* @see Connection
* @since 1.0.0
*/
@InterfaceAudience.Public
@InterfaceStability.Evolving
public interface BufferedMutator extends Closeable {
/**
* Gets the fully qualified table name instance of the table that this BufferedMutator writes to.
*/
TableName getName();
/**
* Returns the {@link org.apache.hadoop.conf.Configuration} object used by this instance.
*
* The reference returned is not a copy, so any change made to it will
* affect this instance.
*/
Configuration getConfiguration();
/**
* Sends a {@link Mutation} to the table. The mutations will be buffered and sent over the
* wire as part of a batch. Currently only supports {@link Put} and {@link Delete} mutations.
*
* @param mutation The data to send.
* @throws IOException if a remote or network exception occurs.
*/
void mutate(Mutation mutation) throws IOException;
/**
* Send some {@link Mutation}s to the table. The mutations will be buffered and sent over the
* wire as part of a batch. There is no guarantee of sending entire content of {@code mutations}
* in a single batch; it will be broken up according to the write buffer capacity.
*
* @param mutations The data to send.
* @throws IOException if a remote or network exception occurs.
*/
void mutate(List mutations) throws IOException;
/**
* Performs a {@link #flush()} and releases any resources held.
*
* @throws IOException if a remote or network exception occurs.
*/
@Override
void close() throws IOException;
/**
* Executes all the buffered, asynchronous {@link Mutation} operations and waits until they
* are done.
*
* @throws IOException if a remote or network exception occurs.
*/
void flush() throws IOException;
/**
* Returns the maximum size in bytes of the write buffer for this HTable.
*
* The default value comes from the configuration parameter {@code hbase.client.write.buffer}.
* @return The size of the write buffer in bytes.
*/
long getWriteBufferSize();
/**
* Listens for asynchronous exceptions on a {@link BufferedMutator}.
*/
@InterfaceAudience.Public
@InterfaceStability.Evolving
interface ExceptionListener {
public void onException(RetriesExhaustedWithDetailsException exception,
BufferedMutator mutator) throws RetriesExhaustedWithDetailsException;
}
}