/**
* Calculate the number of data bytes for the given id. As the length is encoded in the id, this
* operation does not cause any reads in the map.
*
* @param id the id
* @return the length
*/
public long length(byte[] id) {
ByteBuffer idBuffer = ByteBuffer.wrap(id);
long length = 0;
while (idBuffer.hasRemaining()) {
switch (idBuffer.get()) {
case 0:
// in-place: 0, len (int), data
int len = DataUtils.readVarInt(idBuffer);
idBuffer.position(idBuffer.position() + len);
length += len;
break;
case 1:
// block: 1, len (int), blockId (long)
length += DataUtils.readVarInt(idBuffer);
DataUtils.readVarLong(idBuffer);
break;
case 2:
// indirect: 2, total len (long), blockId (long)
length += DataUtils.readVarLong(idBuffer);
DataUtils.readVarLong(idBuffer);
break;
default:
throw DataUtils.newIllegalArgumentException("Unsupported id {0}", Arrays.toString(id));
}
}
return length;
}
/**
* Remove all stored blocks for the given id.
*
* @param id the id
*/
public void remove(byte[] id) {
ByteBuffer idBuffer = ByteBuffer.wrap(id);
while (idBuffer.hasRemaining()) {
switch (idBuffer.get()) {
case 0:
// in-place: 0, len (int), data
int len = DataUtils.readVarInt(idBuffer);
idBuffer.position(idBuffer.position() + len);
break;
case 1:
// block: 1, len (int), blockId (long)
DataUtils.readVarInt(idBuffer);
long k = DataUtils.readVarLong(idBuffer);
map.remove(k);
break;
case 2:
// indirect: 2, total len (long), blockId (long)
DataUtils.readVarLong(idBuffer);
long k2 = DataUtils.readVarLong(idBuffer);
// recurse
remove(map.get(k2));
map.remove(k2);
break;
default:
throw DataUtils.newIllegalArgumentException("Unsupported id {0}", Arrays.toString(id));
}
}
}
/**
* Get the key of the biggest block, of -1 for inline data. This method is used to garbage collect
* orphaned blocks.
*
* @param id the id
* @return the key, or -1
*/
public long getMaxBlockKey(byte[] id) {
long maxKey = -1;
ByteBuffer idBuffer = ByteBuffer.wrap(id);
while (idBuffer.hasRemaining()) {
switch (idBuffer.get()) {
case 0:
// in-place: 0, len (int), data
int len = DataUtils.readVarInt(idBuffer);
idBuffer.position(idBuffer.position() + len);
break;
case 1:
// block: 1, len (int), blockId (long)
DataUtils.readVarInt(idBuffer);
long k = DataUtils.readVarLong(idBuffer);
maxKey = Math.max(maxKey, k);
break;
case 2:
// indirect: 2, total len (long), blockId (long)
DataUtils.readVarLong(idBuffer);
long k2 = DataUtils.readVarLong(idBuffer);
// recurse
byte[] r = map.get(k2);
maxKey = Math.max(maxKey, getMaxBlockKey(r));
break;
default:
throw DataUtils.newIllegalArgumentException("Unsupported id {0}", Arrays.toString(id));
}
}
return maxKey;
}
private ByteArrayInputStream nextBuffer() {
while (idBuffer.hasRemaining()) {
switch (idBuffer.get()) {
case 0:
{
int len = DataUtils.readVarInt(idBuffer);
if (skip >= len) {
skip -= len;
idBuffer.position(idBuffer.position() + len);
continue;
}
int p = (int) (idBuffer.position() + skip);
int l = (int) (len - skip);
idBuffer.position(p + l);
return new ByteArrayInputStream(idBuffer.array(), p, l);
}
case 1:
{
int len = DataUtils.readVarInt(idBuffer);
long key = DataUtils.readVarLong(idBuffer);
if (skip >= len) {
skip -= len;
continue;
}
byte[] data = store.getBlock(key);
int s = (int) skip;
skip = 0;
return new ByteArrayInputStream(data, s, data.length - s);
}
case 2:
{
long len = DataUtils.readVarLong(idBuffer);
long key = DataUtils.readVarLong(idBuffer);
if (skip >= len) {
skip -= len;
continue;
}
byte[] k = store.getBlock(key);
ByteBuffer newBuffer =
ByteBuffer.allocate(k.length + idBuffer.limit() - idBuffer.position());
newBuffer.put(k);
newBuffer.put(idBuffer);
newBuffer.flip();
idBuffer = newBuffer;
return nextBuffer();
}
default:
throw DataUtils.newIllegalArgumentException(
"Unsupported id {0}", Arrays.toString(idBuffer.array()));
}
}
return null;
}
/**
* Convert the id to a human readable string.
*
* @param id the stream id
* @return the string
*/
public static String toString(byte[] id) {
StringBuilder buff = new StringBuilder();
ByteBuffer idBuffer = ByteBuffer.wrap(id);
long length = 0;
while (idBuffer.hasRemaining()) {
long block;
int len;
switch (idBuffer.get()) {
case 0:
// in-place: 0, len (int), data
len = DataUtils.readVarInt(idBuffer);
idBuffer.position(idBuffer.position() + len);
buff.append("data len=").append(len);
length += len;
break;
case 1:
// block: 1, len (int), blockId (long)
len = DataUtils.readVarInt(idBuffer);
length += len;
block = DataUtils.readVarLong(idBuffer);
buff.append("block ").append(block).append(" len=").append(len);
break;
case 2:
// indirect: 2, total len (long), blockId (long)
len = DataUtils.readVarInt(idBuffer);
length += DataUtils.readVarLong(idBuffer);
block = DataUtils.readVarLong(idBuffer);
buff.append("indirect block ").append(block).append(" len=").append(len);
break;
default:
buff.append("error");
}
buff.append(", ");
}
buff.append("length=").append(length);
return buff.toString();
}
