/**
* Compute the first few words of the XOR aggregate between two iterators.
*
* @param container where to write
* @param desiredrlwcount number of words to be written (max)
* @param rlwi first iterator to aggregate
* @param rlwj second iterator to aggregate
*/
public static void xorToContainer(
final BitmapStorage32 container,
int desiredrlwcount,
final IteratingRLW32 rlwi,
IteratingRLW32 rlwj) {
while ((rlwi.size() > 0) && (rlwj.size() > 0) && (desiredrlwcount-- > 0)) {
while ((rlwi.getRunningLength() > 0) || (rlwj.getRunningLength() > 0)) {
final boolean i_is_prey = rlwi.getRunningLength() < rlwj.getRunningLength();
final IteratingRLW32 prey = i_is_prey ? rlwi : rlwj;
final IteratingRLW32 predator = i_is_prey ? rlwj : rlwi;
if (!predator.getRunningBit()) {
int index = discharge(container, prey, predator.getRunningLength());
container.addStreamOfEmptyWords(false, predator.getRunningLength() - index);
predator.discardFirstWords(predator.getRunningLength());
} else {
int index = dischargeNegated(container, prey, predator.getRunningLength());
container.addStreamOfEmptyWords(true, predator.getRunningLength() - index);
predator.discardFirstWords(predator.getRunningLength());
}
}
final int nbre_literal =
Math.min(rlwi.getNumberOfLiteralWords(), rlwj.getNumberOfLiteralWords());
if (nbre_literal > 0) {
desiredrlwcount -= nbre_literal;
for (int k = 0; k < nbre_literal; ++k)
container.addWord(rlwi.getLiteralWordAt(k) ^ rlwj.getLiteralWordAt(k));
rlwi.discardFirstWords(nbre_literal);
rlwj.discardFirstWords(nbre_literal);
}
}
}
/**
* Compute the xor aggregate using a temporary uncompressed bitmap.
*
* @param container where the aggregate is written
* @param bufSize buffer size used during the computation in 64-bit words
* @param bitmaps the source bitmaps
*/
public static void bufferedxorWithContainer(
final BitmapStorage32 container, final int bufSize, final EWAHCompressedBitmap32... bitmaps) {
int range = 0;
EWAHCompressedBitmap32[] sbitmaps = bitmaps.clone();
Arrays.sort(
sbitmaps,
new Comparator<EWAHCompressedBitmap32>() {
@Override
public int compare(EWAHCompressedBitmap32 a, EWAHCompressedBitmap32 b) {
return b.sizeInBits() - a.sizeInBits();
}
});
java.util.ArrayList<IteratingBufferedRunningLengthWord32> al =
new java.util.ArrayList<IteratingBufferedRunningLengthWord32>();
for (EWAHCompressedBitmap32 bitmap : sbitmaps) {
if (bitmap.sizeInBits() > range) range = bitmap.sizeInBits();
al.add(new IteratingBufferedRunningLengthWord32(bitmap));
}
int[] hardbitmap = new int[bufSize];
int maxr = al.size();
while (maxr > 0) {
int effective = 0;
for (int k = 0; k < maxr; ++k) {
if (al.get(k).size() > 0) {
int eff = IteratorAggregation32.inplacexor(hardbitmap, al.get(k));
if (eff > effective) effective = eff;
} else maxr = k;
}
for (int k = 0; k < effective; ++k) container.addWord(hardbitmap[k]);
Arrays.fill(hardbitmap, 0);
}
container.setSizeInBitsWithinLastWord(range);
}
/**
* Compute the and aggregate using a temporary uncompressed bitmap.
*
* <p>This function does not seek to match the "sizeinbits" attributes of the input bitmaps.
*
* @param container where the aggregate is written
* @param bufSize buffer size used during the computation in 64-bit words (per input bitmap)
* @param bitmaps the source bitmaps
*/
public static void bufferedandWithContainer(
final BitmapStorage32 container, final int bufSize, final EWAHCompressedBitmap32... bitmaps) {
java.util.LinkedList<IteratingBufferedRunningLengthWord32> al =
new java.util.LinkedList<IteratingBufferedRunningLengthWord32>();
for (EWAHCompressedBitmap32 bitmap : bitmaps) {
al.add(new IteratingBufferedRunningLengthWord32(bitmap));
}
int[] hardbitmap = new int[bufSize * bitmaps.length];
for (IteratingRLW32 i : al)
if (i.size() == 0) {
al.clear();
break;
}
while (!al.isEmpty()) {
Arrays.fill(hardbitmap, ~0);
int effective = Integer.MAX_VALUE;
for (IteratingRLW32 i : al) {
int eff = IteratorAggregation32.inplaceand(hardbitmap, i);
if (eff < effective) effective = eff;
}
for (int k = 0; k < effective; ++k) container.addWord(hardbitmap[k]);
for (IteratingRLW32 i : al)
if (i.size() == 0) {
al.clear();
break;
}
}
}
/**
* Write out up to max words, returns how many were written
*
* @param container target for writes
* @param i source of data
* @param max maximal number of writes
* @return how many written
*/
protected static int discharge(final BitmapStorage32 container, IteratingRLW32 i, int max) {
int counter = 0;
while (i.size() > 0 && counter < max) {
int l1 = i.getRunningLength();
if (l1 > 0) {
if (l1 + counter > max) l1 = max - counter;
container.addStreamOfEmptyWords(i.getRunningBit(), l1);
counter += l1;
}
int l = i.getNumberOfLiteralWords();
if (l + counter > max) l = max - counter;
for (int k = 0; k < l; ++k) {
container.addWord(i.getLiteralWordAt(k));
}
counter += l;
i.discardFirstWords(l + l1);
}
return counter;
}
/**
* Write out the content of the iterator, but as if it were all zeros.
*
* @param container where we write
* @param i the iterator
*/
protected static void dischargeAsEmpty(final BitmapStorage32 container, final IteratingRLW32 i) {
while (i.size() > 0) {
container.addStreamOfEmptyWords(false, i.size());
i.next();
}
}
