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import com.googlecode.javaewah.EWAHCompressedBitmap;

import java.io.*;

/**

* @author lemire

*

*/

public class example {

/**

* @param args arguments from the command line

* @throws IOException if an IO error occurs

*/

public static void main(final String[] args) throws Exception {

EWAHCompressedBitmap ewahBitmap1 = EWAHCompressedBitmap.bitmapOf(0,2,55,64,1<<30);

EWAHCompressedBitmap ewahBitmap2 = EWAHCompressedBitmap.bitmapOf(1,3,64,1<<30);

System.out.println("bitmap 1: "+ewahBitmap1);

System.out.println("bitmap 2: "+ewahBitmap2);

// or

EWAHCompressedBitmap orbitmap = ewahBitmap1.or(ewahBitmap2);

System.out.println("bitmap 1 OR bitmap 2: "+orbitmap);

System.out.println("memory usage: " + orbitmap.sizeInBytes() + " bytes");

// and

EWAHCompressedBitmap andbitmap = ewahBitmap1.and(ewahBitmap2);

System.out.println("bitmap 1 AND bitmap 2: "+andbitmap);

System.out.println("memory usage: " + andbitmap.sizeInBytes() + " bytes");

// xor

EWAHCompressedBitmap xorbitmap = ewahBitmap1.xor(ewahBitmap2);

System.out.println("bitmap 1 XOR bitmap 2:"+xorbitmap);

System.out.println("memory usage: " + xorbitmap.sizeInBytes() + " bytes");

// fast aggregation over many bitmaps

EWAHCompressedBitmap ewahBitmap3 = EWAHCompressedBitmap.bitmapOf(5,55,1<<30);

EWAHCompressedBitmap ewahBitmap4 = EWAHCompressedBitmap.bitmapOf(4,66,1<<30);

System.out.println("bitmap 3: "+ewahBitmap3);

System.out.println("bitmap 4: "+ewahBitmap4);

andbitmap = EWAHCompressedBitmap.and(ewahBitmap1,ewahBitmap2,

ewahBitmap3,ewahBitmap4);

System.out.println("b1 AND b2 AND b3 AND b4: "+andbitmap);

// serialization

ByteArrayOutputStream bos = new ByteArrayOutputStream();

// Note: you could use a file output steam instead of ByteArrayOutputStream

ObjectOutputStream oo = new ObjectOutputStream(bos);

ewahBitmap1.writeExternal(oo);

oo.close();

ewahBitmap1 = null;

ewahBitmap1 = new EWAHCompressedBitmap();

ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());

ewahBitmap1.readExternal(new ObjectInputStream(bis));

System.out.println("bitmap 1 (recovered) : "+ewahBitmap1);

//

// support for threshold function (new as of version 0.8.0):

// mark as true a bit that occurs at least T times in the source

// bitmaps

//

EWAHCompressedBitmap threshold2 = EWAHCompressedBitmap.threshold(2, ewahBitmap1,ewahBitmap2,

ewahBitmap3,ewahBitmap4);

System.out.println("threshold 2 : "+threshold2);

}

}