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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();
}
}
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