org.calrissian.accumulorecipes.commons.hadoop.AccumuloMultipleOuputs.java Source code

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Here is the source code for org.calrissian.accumulorecipes.commons.hadoop.AccumuloMultipleOuputs.java

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/*
 * Copyright (C) 2015 The Calrissian Authors
 *
 * Licensed 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.calrissian.accumulorecipes.commons.hadoop;

import java.io.IOException;

import org.apache.accumulo.core.client.mapred.AccumuloFileOutputFormat;
import org.apache.accumulo.core.data.Key;
import org.apache.accumulo.core.data.Value;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.RecordWriter;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.mapred.lib.MultipleOutputFormat;
import org.apache.hadoop.util.Progressable;

/**
 * A wrapper around the {@link org.apache.accumulo.core.client.mapred.AccumuloFileOutputFormat} that will output
 * each group into a separate folder in HDFS. This enables keys/values for multiple tables to be partitioned, sorted,
 * and output within the same mapreduce job.`
 */
public class AccumuloMultipleOuputs extends MultipleOutputFormat<GroupedKey, Value> {

    @Override
    protected RecordWriter<GroupedKey, Value> getBaseRecordWriter(FileSystem fileSystem, JobConf jobConf, String s,
            Progressable progressable) throws IOException {
        return new GroupedKeyRecordWriter(fileSystem, jobConf, s, progressable);
    }

    /**
     * Makes sure that a file for a specific grouped key is always placed in the folder of that group
     * @param key
     * @param value
     * @param name
     * @return
     */
    @Override
    protected String generateFileNameForKeyValue(GroupedKey key, Value value, String name) {
        return key.getGroup() + "/" + key.getGroup() + "-" + name;
    }

    protected static class GroupedKeyRecordWriter implements RecordWriter<GroupedKey, Value> {

        private final RecordWriter<Key, Value> internalRecordWriter;

        public GroupedKeyRecordWriter(FileSystem fileSystem, JobConf jobConf, String s, Progressable progressable)
                throws IOException {
            this.internalRecordWriter = new AccumuloFileOutputFormat().getRecordWriter(fileSystem, jobConf, s,
                    progressable);
        }

        @Override
        public void write(GroupedKey key, Value value) throws IOException {
            internalRecordWriter.write(key.getKey(), value);
        }

        @Override
        public void close(Reporter reporter) throws IOException {
            internalRecordWriter.close(reporter);
        }
    }
}