org.apache.hadoop.hbase.client.BufferedMutator Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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*
* 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,
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*/
package org.apache.hadoop.hbase.client;
import java.io.Closeable;
import java.io.IOException;
import java.util.List;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.TableName;
import org.apache.yetus.audience.InterfaceAudience;
/**
*
* 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
* HTable#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
public interface BufferedMutator extends Closeable {
/**
* Key to use setting non-default BufferedMutator implementation in Configuration.
*/
String CLASSNAME_KEY = "hbase.client.bufferedmutator.classname";
/**
* Having the timer tick run more often that once every 100ms is needless and will probably cause
* too many timer events firing having a negative impact on performance.
*/
long MIN_WRITE_BUFFER_PERIODIC_FLUSH_TIMERTICK_MS = 100;
/**
* 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;
/**
* Sets the maximum time before the buffer is automatically flushed checking once per second.
* @param timeoutMs The maximum number of milliseconds how long records may be buffered before
* they are flushed. Set to 0 to disable.
*/
default void setWriteBufferPeriodicFlush(long timeoutMs) {
setWriteBufferPeriodicFlush(timeoutMs, 1000L);
}
/**
* Sets the maximum time before the buffer is automatically flushed.
* @param timeoutMs The maximum number of milliseconds how long records may be buffered before
* they are flushed. Set to 0 to disable.
* @param timerTickMs The number of milliseconds between each check if the timeout has been
* exceeded. Must be 100ms (as defined in
* {@link #MIN_WRITE_BUFFER_PERIODIC_FLUSH_TIMERTICK_MS}) or larger to avoid
* performance problems.
*/
default void setWriteBufferPeriodicFlush(long timeoutMs, long timerTickMs) {
throw new UnsupportedOperationException(
"The BufferedMutator::setWriteBufferPeriodicFlush has not been implemented");
}
/**
* Disable periodic flushing of the write buffer.
*/
default void disableWriteBufferPeriodicFlush() {
setWriteBufferPeriodicFlush(0, MIN_WRITE_BUFFER_PERIODIC_FLUSH_TIMERTICK_MS);
}
/**
* Returns the current periodic flush timeout value in milliseconds.
* @return The maximum number of milliseconds how long records may be buffered before they are
* flushed. The value 0 means this is disabled.
*/
default long getWriteBufferPeriodicFlushTimeoutMs() {
throw new UnsupportedOperationException(
"The BufferedMutator::getWriteBufferPeriodicFlushTimeoutMs has not been implemented");
}
/**
* Returns the current periodic flush timertick interval in milliseconds.
* @return The number of milliseconds between each check if the timeout has been exceeded. This
* value only has a real meaning if the timeout has been set to > 0
*/
default long getWriteBufferPeriodicFlushTimerTickMs() {
throw new UnsupportedOperationException(
"The BufferedMutator::getWriteBufferPeriodicFlushTimerTickMs has not been implemented");
}
/**
* 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.
*/
default long getWriteBufferSize() {
throw new UnsupportedOperationException(
"The BufferedMutator::getWriteBufferSize has not been implemented");
}
/**
* Set rpc timeout for this mutator instance
*/
default void setRpcTimeout(int timeout) {
throw new UnsupportedOperationException(
"The BufferedMutator::setRpcTimeout has not been implemented");
}
/**
* Set operation timeout for this mutator instance
*/
default void setOperationTimeout(int timeout) {
throw new UnsupportedOperationException(
"The BufferedMutator::setOperationTimeout has not been implemented");
}
/**
* Listens for asynchronous exceptions on a {@link BufferedMutator}.
*/
@InterfaceAudience.Public
interface ExceptionListener {
public void onException(RetriesExhaustedWithDetailsException exception, BufferedMutator mutator)
throws RetriesExhaustedWithDetailsException;
}
}