EWAHCompressedBitmap bitmapAnd = bitmapBop(bitmap1, bitmap2);
BitmapObjectOutput bitmapObjOut = new BitmapObjectOutput();
try {
bitmapAnd.writeExternal(bitmapObjOut);
} catch (IOException e) {
throw new RuntimeException(e);
}
ret.clear();
List<LongWritable> retList = bitmapToWordArray(bitmapAnd);