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import com.googlecode.javaewah.EWAHCompressedBitmap;

import java.io.*;

import java.nio.*;

import java.nio.channels.FileChannel;

public class MemoryMappingExample {

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

File tmpfile = File.createTempFile("javaewah", "bin");

tmpfile.deleteOnExit();

final FileOutputStream fos = new FileOutputStream(tmpfile);

EWAHCompressedBitmap ewahBitmap = EWAHCompressedBitmap.bitmapOf(0, 2, 55,

64, 1 << 30);

System.out.println("Created the bitmap "+ewahBitmap);

ewahBitmap.serialize(new DataOutputStream(fos));

long totalcount = fos.getChannel().position();

System.out.println("Serialized total count = "+totalcount+" bytes");

fos.close();

RandomAccessFile memoryMappedFile = new RandomAccessFile(tmpfile, "r");

ByteBuffer bb = memoryMappedFile.getChannel().map(FileChannel.MapMode.READ_ONLY, 0, totalcount);

EWAHCompressedBitmap mapped = new EWAHCompressedBitmap(bb);

System.out.println("Mapped the bitmap "+mapped);

memoryMappedFile.close();

}

}