/// <summary>
/// Saves records loaded in memory to disk.
/// </summary>
/// <remarks>
/// <see cref="IsamDataFileBase{T}.Save"/> is equivalent to <see cref="FileStream.Flush()"/> when records are not loaded in memory.
/// </remarks>
public override void Save()
{
if (m_legacyMode == MetadataFileLegacyMode.Enabled)
{
base.Save();
}
if (m_legacyMode == MetadataFileLegacyMode.Compatible)
{
SaveLegacyMetadataFile();
}
if (m_legacyMode == MetadataFileLegacyMode.Disabled || m_legacyMode == MetadataFileLegacyMode.Compatible)
{
if (!IsOpen)
{
throw new InvalidOperationException(string.Format("MetadataFile \"{0}\" is not open", FileName));
}
// Waits for any pending request to save records before completing.
SaveWaitHandle.Wait();
// Waits for any prior request to load records before completing.
LoadWaitHandle.Wait();
SaveWaitHandle.Reset();
try
{
OnDataSaving();
lock (FileDataLock)
{
FileData.SetLength(0);
BinaryWriter writer = new BinaryWriter(FileData);
writer.Write(m_records.Count);
foreach (MetadataRecord record in m_records.Values)
{
record.WriteImage(writer);
}
FileData.Flush();
File.SetLastWriteTime(FileName, DateTime.Now);
}
OnDataSaved();
}
finally
{
SaveWaitHandle.Set();
}
}
}
/// <summary>
/// Loads records from disk into memory.
/// </summary>
public override void Load()
{
if (m_legacyMode == MetadataFileLegacyMode.Enabled)
{
base.Load();
return;
}
if (!IsOpen)
{
throw new InvalidOperationException(string.Format("MetadataFile \"{0}\" is not open", FileName));
}
// Waits for any pending request to save records before completing.
SaveWaitHandle.Wait();
// Waits for any prior request to load records before completing.
LoadWaitHandle.Wait();
LoadWaitHandle.Reset();
try
{
OnDataLoading();
lock (FileDataLock)
{
if (FileData.Length > 0)
{
FileData.Seek(0, SeekOrigin.Begin);
BinaryReader reader = new BinaryReader(FileData);
int count = reader.ReadInt32();
for (int i = 0; i < count; i++)
{
MetadataRecord record = new MetadataRecord(reader);
m_records[record.HistorianID] = record;
}
}
}
OnDataLoaded();
}
finally
{
LoadWaitHandle.Set();
}
}