com.aliyun.odps.mapred.local.MapOutputBuffer.java Source code

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Here is the source code for com.aliyun.odps.mapred.local.MapOutputBuffer.java

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/*
 * 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 com.aliyun.odps.mapred.local;

import java.util.ArrayList;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.PriorityQueue;
import java.util.Queue;

import org.apache.commons.lang.ArrayUtils;

import com.aliyun.odps.Column;
import com.aliyun.odps.data.Record;
import com.aliyun.odps.mapred.bridge.WritableRecord;
import com.aliyun.odps.mapred.conf.JobConf;
import com.aliyun.odps.mapred.conf.JobConf.SortOrder;
import com.aliyun.odps.mapred.local.utils.LocalColumnBasedRecordComparator;
import com.aliyun.odps.pipeline.Pipeline;
import com.aliyun.odps.pipeline.Pipeline.TransformNode;

public class MapOutputBuffer {

    int[] partColIdxs;
    int numReduce;
    private List<PriorityQueue<Object[]>> buffers;
    Comparator<Object[]> comparator;

    public MapOutputBuffer(JobConf conf, int reduceNum) {

        Column[] key = conf.getMapOutputKeySchema();
        if (key != null) {
            String[] partCols = conf.getPartitionColumns();
            this.partColIdxs = new int[partCols.length];
            Map<String, Integer> reverseLookupMap = new HashMap<String, Integer>();
            int i = 0;
            for (Column c : key) {
                reverseLookupMap.put(c.getName(), i);
                i++;
            }
            i = 0;
            for (String col : partCols) {
                partColIdxs[i] = reverseLookupMap.get(col);
            }

            numReduce = reduceNum;
            String[] sortColumns = conf.getOutputKeySortColumns();
            SortOrder[] sortOrders = conf.getOutputKeySortOrder();
            comparator = new LocalColumnBasedRecordComparator(sortColumns, key, sortOrders);
            buffers = new ArrayList<PriorityQueue<Object[]>>(numReduce);
            for (i = 0; i < numReduce; i++) {
                buffers.add(new PriorityQueue<Object[]>(16, comparator));
            }
        }

    }

    public MapOutputBuffer(JobConf conf, Pipeline pipeline, String taskId, int reduceNum) {
        int pipeIndex = Integer.parseInt(taskId.split("_")[0].substring(1)) - 1;
        TransformNode pipeNode = pipeline.getNode(pipeIndex);
        Column[] key = pipeNode.getOutputKeySchema();
        if (key != null) {
            String[] partCols = pipeNode.getPartitionColumns();
            this.partColIdxs = new int[partCols.length];
            Map<String, Integer> reverseLookupMap = new HashMap<String, Integer>();
            int i = 0;
            for (Column c : key) {
                reverseLookupMap.put(c.getName(), i);
                i++;
            }
            i = 0;
            for (String col : partCols) {
                partColIdxs[i] = reverseLookupMap.get(col);
            }

            // reduce copy count
            numReduce = reduceNum;
            String[] sortColumns = pipeNode.getOutputKeySortColumns();
            SortOrder[] sortOrders = pipeNode.getOutputKeySortOrder();
            comparator = new LocalColumnBasedRecordComparator(sortColumns, key, sortOrders);
            buffers = new ArrayList<PriorityQueue<Object[]>>(numReduce);
            for (i = 0; i < numReduce; i++) {
                buffers.add(new PriorityQueue<Object[]>(16, comparator));
            }
        }

    }

    /**
     * Hard coded partition strategy. Should be the same as FUXI hash function.
     *
     * @return
     */
    protected int getPartition(Record key) {
        int partition = 0;
        for (int i : partColIdxs) {
            Object o = key.get(i);
            if (o != null) {
                partition = partition * 32 + o.hashCode();
            } else {
                partition = partition * 32;
            }
        }
        return Math.abs(partition) % numReduce;
    }

    public void add(Record key, Record value) {
        int partition = getPartition(key);
        buffers.get(partition).offer(ArrayUtils.addAll(((WritableRecord) key).toWritableArray().clone(),
                ((WritableRecord) value).toWritableArray().clone()));
    }

    public void add(Record key, Record value, int partition) {
        buffers.get(partition).offer(ArrayUtils.addAll(((WritableRecord) key).toWritableArray().clone(),
                ((WritableRecord) value).toWritableArray().clone()));
    }

    public Queue<Object[]> getPartitionQueue(int partition) {
        return buffers.get(partition);
    }

    public Comparator<? super Object[]> getComparator() {
        return comparator;
    }

    public long getTotalRecordCount() {
        if (buffers == null) {
            return 0;
        }
        long totalCount = 0;
        for (PriorityQueue<Object[]> item : buffers) {
            if (item == null) {
                continue;
            }
            totalCount += item.size();
        }
        return totalCount;
    }

    public void add(Record record, String label) {
        // do nothing
    }
}