learn.jersey.services.BufferedMutatorExample.java Source code

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Here is the source code for learn.jersey.services.BufferedMutatorExample.java

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package learn.jersey.services;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

/**
*
* 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.
*/

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.BufferedMutator;
import org.apache.hadoop.hbase.client.BufferedMutatorParams;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.RetriesExhaustedWithDetailsException;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;

/**
 * An example of using the {@link BufferedMutator} interface.
 */
public class BufferedMutatorExample extends Configured implements Tool {

    private static final Log LOG = LogFactory.getLog(BufferedMutatorExample.class);

    private static final int POOL_SIZE = 10;
    private static final int TASK_COUNT = 100;
    private static final TableName TABLE = TableName.valueOf("foo");
    private static final byte[] FAMILY = Bytes.toBytes("f");

    @Override
    public int run(String[] args) throws InterruptedException, ExecutionException, TimeoutException {

        /** a callback invoked when an asynchronous write fails. */
        final BufferedMutator.ExceptionListener listener = new BufferedMutator.ExceptionListener() {
            @Override
            public void onException(RetriesExhaustedWithDetailsException e, BufferedMutator mutator) {
                for (int i = 0; i < e.getNumExceptions(); i++) {
                    LOG.info("Failed to sent put " + e.getRow(i) + ".");
                }
            }
        };
        BufferedMutatorParams params = new BufferedMutatorParams(TABLE).listener(listener);

        //
        // step 1: create a single Connection and a BufferedMutator, shared by
        // all worker threads.
        //
        try (final Connection conn = ConnectionFactory.createConnection(getConf());
                final BufferedMutator mutator = conn.getBufferedMutator(params)) {

            /** worker pool that operates on BufferedTable instances */
            final ExecutorService workerPool = Executors.newFixedThreadPool(POOL_SIZE);
            List<Future<Void>> futures = new ArrayList<>(TASK_COUNT);

            for (int i = 0; i < TASK_COUNT; i++) {
                futures.add(workerPool.submit(new Callable<Void>() {
                    @Override
                    public Void call() throws Exception {
                        //
                        // step 2: each worker sends edits to the shared
                        // BufferedMutator instance. They all use
                        // the same backing buffer, call-back "listener", and
                        // RPC executor pool.
                        //
                        Put p = new Put(Bytes.toBytes("someRow"));
                        p.addColumn(FAMILY, Bytes.toBytes("someQualifier"), Bytes.toBytes("some value"));
                        mutator.mutate(p);
                        // do work... maybe you want to call mutator.flush()
                        // after many edits to ensure any of
                        // this worker's edits are sent before exiting the
                        // Callable
                        return null;
                    }
                }));
            }

            //
            // step 3: clean up the worker pool, shut down.
            //
            for (Future<Void> f : futures) {
                f.get(5, TimeUnit.MINUTES);
            }
            workerPool.shutdown();
        } catch (IOException e) {
            // exception while creating/destroying Connection or BufferedMutator
            LOG.info("exception while creating/destroying Connection or BufferedMutator", e);
        } // BufferedMutator.close() ensures all work is flushed. Could be the
          // custom listener is
          // invoked from here.
        return 0;
    }

    public static void main(String[] args) throws Exception {
        ToolRunner.run(new BufferedMutatorExample(), args);
    }
}