/**
* 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));
}
}
}
/**
* 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;
}
/**
* 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;
}
/**
* Try to open the file.
*
* @param fileName the file name
* @param readOnly whether the file should only be opened in read-only mode, even if the file is
* writable
* @param encryptionKey the encryption key, or null if encryption is not used
*/
public void open(String fileName, boolean readOnly, char[] encryptionKey) {
if (file != null) {
return;
}
if (fileName != null) {
FilePath p = FilePath.get(fileName);
// if no explicit scheme was specified, NIO is used
if (p instanceof FilePathDisk && !fileName.startsWith(p.getScheme() + ":")) {
// ensure the NIO file system is registered
FilePathNio.class.getName();
fileName = "nio:" + fileName;
}
}
this.fileName = fileName;
FilePath f = FilePath.get(fileName);
FilePath parent = f.getParent();
if (parent != null && !parent.exists()) {
throw DataUtils.newIllegalArgumentException("Directory does not exist: {0}", parent);
}
if (f.exists() && !f.canWrite()) {
readOnly = true;
}
this.readOnly = readOnly;
try {
file = f.open(readOnly ? "r" : "rw");
if (encryptionKey != null) {
byte[] key = FilePathEncrypt.getPasswordBytes(encryptionKey);
encryptedFile = file;
file = new FilePathEncrypt.FileEncrypt(fileName, key, file);
}
file = FilePathCache.wrap(file);
try {
if (readOnly) {
fileLock = file.tryLock(0, Long.MAX_VALUE, true);
} else {
fileLock = file.tryLock();
}
} catch (OverlappingFileLockException e) {
throw DataUtils.newIllegalStateException(
DataUtils.ERROR_FILE_LOCKED, "The file is locked: {0}", fileName, e);
}
if (fileLock == null) {
throw DataUtils.newIllegalStateException(
DataUtils.ERROR_FILE_LOCKED, "The file is locked: {0}", fileName);
}
fileSize = file.size();
} catch (IOException e) {
throw DataUtils.newIllegalStateException(
DataUtils.ERROR_READING_FAILED, "Could not open file {0}", fileName, e);
}
}