/**
* Create a network file for the specified file
*
* @param params FileOpenParams
* @param fid int
* @param stid int
* @param did int
* @param create boolean
* @param dir boolean
* @exception IOException
* @exception FileNotFoundException
*/
public NetworkFile openFile(
FileOpenParams params, int fid, int stid, int did, boolean create, boolean dir)
throws IOException, FileNotFoundException {
// Split the file name to get the name only
String[] paths = FileName.splitPath(params.getPath());
String name = paths[1];
if (params.isStream()) name = name + params.getStreamName();
// Find, or create, the file state for the file/directory
FileState fstate = m_stateCache.findFileState(params.getFullPath(), true);
fstate.setExpiryTime(System.currentTimeMillis() + m_stateCache.getFileStateExpireInterval());
// Check if the file is a directory
DBNetworkFile netFile = null;
if (dir == false) {
// Create the network file and associated file segment
CachedNetworkFile cacheFile = createNetworkFile(fstate, params, name, fid, stid, did);
netFile = cacheFile;
// Check if the file is being opened for sequential access and the data has not yet been
// loaded
FileSegment fileSeg = cacheFile.getFileSegment();
if (create == true || params.isOverwrite() == true) {
// Indicate that the file data is available, this is a new file or the existing file is
// being
// overwritten so there is no data to load.
fileSeg.setStatus(FileSegmentInfo.Available);
} else if (params.isSequentialAccessOnly() && fileSeg.isDataLoading() == false) {
synchronized (cacheFile.getFileState()) {
// Create the temporary file
cacheFile.openFile(create);
cacheFile.closeFile();
// Queue a file data load request
if (fileSeg.isDataLoading() == false)
queueFileRequest(
new SingleFileRequest(
FileRequest.LOAD,
cacheFile.getFileId(),
cacheFile.getStreamId(),
fileSeg.getInfo(),
cacheFile.getFullName(),
fstate));
}
// DEBUG
if (Debug.EnableInfo && hasDebug())
Debug.println(
"ObjIdLoader Queued file load, SEQUENTIAL access, file=" + cacheFile.getFullName());
}
} else {
// Create a placeholder network file for the directory
netFile = new DirectoryNetworkFile(name, fid, did, m_stateCache.getFileStateProxy(fstate));
// Debug
if (Debug.EnableInfo && hasDebug())
Debug.println("ObjIdLoader.openFile() DIR name=" + name + ", state=" + fstate);
}
// Return the network file
return netFile;
}
/**
* Create a file segment to load/save the file data
*
* @param state FileState
* @param params FileOpenParams
* @param fname String
* @param fid int
* @param stid int
* @param did int
* @return CachedNetworkFile
* @exception IOException
*/
private final CachedNetworkFile createNetworkFile(
FileState state, FileOpenParams params, String fname, int fid, int stid, int did)
throws IOException {
// The file state is used to synchronize the creation of the file segment as there may be other
// sessions opening the file at the same time. We have to be careful that only one thread
// creates the
// file segment.
FileSegment fileSeg = null;
CachedNetworkFile netFile = null;
synchronized (state) {
// Check if the file segment has been attached to the file state
FileSegmentInfo fileSegInfo = (FileSegmentInfo) state.findAttribute(DBFileSegmentInfo);
if (fileSegInfo == null) {
// Check if we need to create a new temporary sub-drectory
if (m_tempCount++ >= m_tempMax) createNewTempDirectory();
// Create a unique temporary file name
StringBuffer tempName = new StringBuffer();
tempName.append(getTempFilePrefix());
tempName.append(fid);
if (stid > 0) {
tempName.append("_");
tempName.append(stid);
// DEBUG
if (Debug.EnableInfo && hasDebug()) Debug.println("## Temp file for stream ##");
}
tempName.append(".tmp");
// Create a new file segment
fileSegInfo = new FileSegmentInfo();
fileSeg =
FileSegment.createSegment(
fileSegInfo, tempName.toString(), m_curTempDir, params.isReadOnlyAccess() == false);
// Add the segment to the file state cache
state.addAttribute(DBFileSegmentInfo, fileSegInfo);
// Check if the file is zero length, if so then set the file segment state to indicate it is
// available
DBFileInfo finfo = (DBFileInfo) state.findAttribute(FileState.FileInformation);
if (finfo != null && finfo.getSize() == 0) fileSeg.setStatus(FileSegmentInfo.Available);
} else {
// Create the file segment to map to the existing temporary file
fileSeg = new FileSegment(fileSegInfo, params.isReadOnlyAccess() == false);
// Check if the temporary file exists, if not then create it
File tempFile = new File(fileSeg.getTemporaryFile());
if (tempFile.exists() == false) {
// Create the temporary file
tempFile.createNewFile();
// Reset the file segment state to indicate a file load is required
fileSeg.setStatus(FileSegmentInfo.Initial);
}
}
// Create the new network file
netFile =
new CachedNetworkFile(
fname, fid, stid, did, m_stateCache.getFileStateProxy(state), fileSeg, this);
netFile.setGrantedAccess(
params.isReadOnlyAccess() ? NetworkFile.READONLY : NetworkFile.READWRITE);
netFile.setSequentialOnly(params.isSequentialAccessOnly());
netFile.setAttributes(params.getAttributes());
netFile.setFullName(params.getPath());
if (stid != 0) netFile.setStreamName(params.getStreamName());
}
// Return the network file
return netFile;
}
