/**
* Returns the length in bytes of a file in the directory.
*
* @throws IOException if the file does not exist
*/
@Override
public final long fileLength(String name) throws IOException {
ensureOpen();
RAMFile file = fileMap.get(name);
if (file == null) {
throw new FileNotFoundException(name);
}
return file.getLength();
}
private final void switchCurrentBuffer() throws IOException {
if (currentBufferIndex == file.numBuffers()) {
currentBuffer = file.addBuffer(BUFFER_SIZE);
} else {
currentBuffer = file.getBuffer(currentBufferIndex);
}
bufferPosition = 0;
bufferStart = (long) BUFFER_SIZE * (long) currentBufferIndex;
bufferLength = currentBuffer.length;
}
@Override
public void deleteFile(String name) throws IOException {
ensureOpen();
RAMFile file = fileMap.remove(name);
if (file != null) {
file.directory = null;
sizeInBytes.addAndGet(-file.sizeInBytes);
} else {
throw new FileNotFoundException(name);
}
}
@Override
public IndexOutput createOutput(String name, IOContext context) throws IOException {
ensureOpen();
RAMFile file = newRAMFile();
RAMFile existing = fileMap.remove(name);
if (existing != null) {
sizeInBytes.addAndGet(-existing.sizeInBytes);
existing.directory = null;
}
fileMap.put(name, file);
return new RAMOutputStream(name, file, true);
}
/** Resets this to an empty file. */
public void reset() {
currentBuffer = null;
currentBufferIndex = -1;
bufferPosition = 0;
bufferStart = 0;
bufferLength = 0;
file.setLength(0);
}
private final void switchCurrentBuffer(boolean enforceEOF) throws IOException {
bufferStart = (long) BUFFER_SIZE * (long) currentBufferIndex;
if (currentBufferIndex >= file.numBuffers()) {
// end of file reached, no more buffers left
if (enforceEOF) {
throw new EOFException("Read past EOF (resource: " + this + ")");
} else {
// Force EOF if a read takes place at this position
currentBufferIndex--;
bufferPosition = BUFFER_SIZE;
}
} else {
currentBuffer = file.getBuffer(currentBufferIndex);
bufferPosition = 0;
long buflen = length - bufferStart;
bufferLength = buflen > BUFFER_SIZE ? BUFFER_SIZE : (int) buflen;
}
}
/** Copy the current contents of this buffer to the named output. */
public void writeTo(IndexOutput out) throws IOException {
flush();
final long end = file.length;
long pos = 0;
int buffer = 0;
while (pos < end) {
int length = BUFFER_SIZE;
long nextPos = pos + length;
if (nextPos > end) { // at the last buffer
length = (int) (end - pos);
}
out.writeBytes(file.getBuffer(buffer++), length);
pos = nextPos;
}
}
/** Copy the current contents of this buffer to output byte array */
public void writeTo(byte[] bytes, int offset) throws IOException {
flush();
final long end = file.length;
long pos = 0;
int buffer = 0;
int bytesUpto = offset;
while (pos < end) {
int length = BUFFER_SIZE;
long nextPos = pos + length;
if (nextPos > end) { // at the last buffer
length = (int) (end - pos);
}
System.arraycopy(file.getBuffer(buffer++), 0, bytes, bytesUpto, length);
bytesUpto += length;
pos = nextPos;
}
}
/** @return size in bytes */
public long getSizeInBytes() {
return buffer.getSizeInBytes();
}
/** Returns byte usage of all buffers. */
public long sizeInBytes() {
return file.numBuffers() * BUFFER_SIZE;
}
private void setFileLength() {
long pointer = bufferStart + bufferPosition;
if (pointer > file.length) {
file.setLength(pointer);
}
}