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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 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: "+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(55,5,1<<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);
}
}
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