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import com.googlecode.javaewah.EWAHCompressedBitmap;

import java.io.*;

public class example {

public static String toSetBitString(EWAHCompressedBitmap b) {

String s = "";

for (int k : b)

s+= k+" ";

return s;

}

public static void main(String[] args) throws java.io.IOException {

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

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

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

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

// or

EWAHCompressedBitmap orbitmap = ewahBitmap1.or(ewahBitmap2);

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

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

// and

EWAHCompressedBitmap andbitmap = ewahBitmap1.and(ewahBitmap2);

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

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

// xor

EWAHCompressedBitmap xorbitmap = ewahBitmap1.xor(ewahBitmap2);

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

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

// fast aggregation over many bitmaps

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

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

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

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

andbitmap = EWAHCompressedBitmap.and(ewahBitmap1,ewahBitmap2,

ewahBitmap3,ewahBitmap4);

System.out.println("b1 AND b2 AND b3 AND b4: "+toSetBitString(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) : "+toSetBitString(ewahBitmap1));

}

}