org.apache.carbondata.hadoop.api.DistributableDataMapFormat.java Source code

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Here is the source code for org.apache.carbondata.hadoop.api.DistributableDataMapFormat.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 org.apache.carbondata.hadoop.api;

import java.io.IOException;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.apache.carbondata.core.datamap.DataMapDistributable;
import org.apache.carbondata.core.datamap.DataMapStoreManager;
import org.apache.carbondata.core.datamap.TableDataMap;
import org.apache.carbondata.core.indexstore.Blocklet;
import org.apache.carbondata.core.metadata.AbsoluteTableIdentifier;
import org.apache.carbondata.core.scan.filter.resolver.FilterResolverIntf;
import org.apache.carbondata.hadoop.util.ObjectSerializationUtil;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.JobContext;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;

/**
 * Input format for datamaps, it makes the datamap pruning distributable.
 */
public class DistributableDataMapFormat extends FileInputFormat<Void, Blocklet> implements Serializable {

    private static final String FILTER_EXP = "mapreduce.input.distributed.datamap.filter";

    private AbsoluteTableIdentifier identifier;

    private String dataMapName;

    private List<String> validSegments;

    private String className;

    public DistributableDataMapFormat(AbsoluteTableIdentifier identifier, String dataMapName,
            List<String> validSegments, String className) {
        this.identifier = identifier;
        this.dataMapName = dataMapName;
        this.validSegments = validSegments;
        this.className = className;
    }

    public static void setFilterExp(Configuration configuration, FilterResolverIntf filterExp) throws IOException {
        if (filterExp != null) {
            String string = ObjectSerializationUtil.convertObjectToString(filterExp);
            configuration.set(FILTER_EXP, string);
        }
    }

    private static FilterResolverIntf getFilterExp(Configuration configuration) throws IOException {
        String filterString = configuration.get(FILTER_EXP);
        if (filterString != null) {
            Object toObject = ObjectSerializationUtil.convertStringToObject(filterString);
            return (FilterResolverIntf) toObject;
        }
        return null;
    }

    @Override
    public List<InputSplit> getSplits(JobContext job) throws IOException {
        TableDataMap dataMap = DataMapStoreManager.getInstance().getDataMap(identifier, dataMapName, className);
        List<DataMapDistributable> distributables = dataMap.toDistributable(validSegments);
        List<InputSplit> inputSplits = new ArrayList<>(distributables.size());
        inputSplits.addAll(distributables);
        return inputSplits;
    }

    @Override
    public RecordReader<Void, Blocklet> createRecordReader(InputSplit inputSplit,
            TaskAttemptContext taskAttemptContext) throws IOException, InterruptedException {
        return new RecordReader<Void, Blocklet>() {
            private Iterator<Blocklet> blockletIterator;
            private Blocklet currBlocklet;

            @Override
            public void initialize(InputSplit inputSplit, TaskAttemptContext taskAttemptContext)
                    throws IOException, InterruptedException {
                DataMapDistributable distributable = (DataMapDistributable) inputSplit;
                AbsoluteTableIdentifier identifier = AbsoluteTableIdentifier
                        .fromTablePath(distributable.getTablePath());
                TableDataMap dataMap = DataMapStoreManager.getInstance().getDataMap(identifier,
                        distributable.getDataMapName(), distributable.getDataMapFactoryClass());
                blockletIterator = dataMap.prune(distributable, getFilterExp(taskAttemptContext.getConfiguration()))
                        .iterator();
            }

            @Override
            public boolean nextKeyValue() throws IOException, InterruptedException {
                boolean hasNext = blockletIterator.hasNext();
                if (hasNext) {
                    currBlocklet = blockletIterator.next();
                }
                return hasNext;
            }

            @Override
            public Void getCurrentKey() throws IOException, InterruptedException {
                return null;
            }

            @Override
            public Blocklet getCurrentValue() throws IOException, InterruptedException {
                return currBlocklet;
            }

            @Override
            public float getProgress() throws IOException, InterruptedException {
                return 0;
            }

            @Override
            public void close() throws IOException {

            }
        };
    }

}