edu.umn.cs.spatialHadoop.indexing.RTreeLocalIndexer.java Source code

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Here is the source code for edu.umn.cs.spatialHadoop.indexing.RTreeLocalIndexer.java

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/***********************************************************************
* Copyright (c) 2015 by Regents of the University of Minnesota.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Apache License, Version 2.0 which 
* accompanies this distribution and is available at
* http://www.opensource.org/licenses/apache2.0.php.
*
*************************************************************************/
package edu.umn.cs.spatialHadoop.indexing;

import java.io.BufferedInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;

import edu.umn.cs.spatialHadoop.core.Shape;
import edu.umn.cs.spatialHadoop.core.SpatialSite;

/**
 * Indexes local files using R-tree.
 * @author Ahmed Eldawy
 *
 */
public class RTreeLocalIndexer implements LocalIndexer {
    private static final Log LOG = LogFactory.getLog(RTreeLocalIndexer.class);

    /**Configuration of the running job*/
    protected Configuration conf;

    @Override
    public void setup(Configuration conf) throws IOException, InterruptedException {
        this.conf = conf;
    }

    @Override
    public String getExtension() {
        return "rtree";
    }

    @Override
    public void buildLocalIndex(File nonIndexedFile, Path outputIndexedFile, Shape shape)
            throws IOException, InterruptedException {
        // Read all data of the written file in memory
        byte[] cellData = new byte[(int) nonIndexedFile.length()];
        InputStream cellIn = new BufferedInputStream(new FileInputStream(nonIndexedFile));
        cellIn.read(cellData);
        cellIn.close();

        // Build an RTree over the elements read from file
        // Create the output file
        FileSystem outFS = outputIndexedFile.getFileSystem(conf);
        DataOutputStream cellStream = outFS.create(outputIndexedFile);
        cellStream.writeLong(SpatialSite.RTreeFileMarker);
        int degree = 4096 / RTree.NodeSize;
        boolean fastAlgorithm = conf.get(SpatialSite.RTREE_BUILD_MODE, "fast").equals("fast");
        RTree.bulkLoadWrite(cellData, 0, cellData.length, degree, cellStream, shape.clone(), fastAlgorithm);
        cellStream.close();
    }

}