/// <summary>
/// Initializes a new instance of the <see cref="T:iTin.Export.ComponentModel.Writer.WritersCache" /> class.
/// </summary>
/// <param name="settings">A reference to cache settings object.</param>
private WritersCache(WritersCacheSettings settings)
{
SentinelHelper.ArgumentNull(settings);
SentinelHelper.ArgumentNull(settings.Items);
_watchers = new List <FileSystemWatcher>();
_container = GetCompositionContainer(settings);
}
/// <summary>
/// Gets writers repository.
/// </summary>
/// <param name="settings">Writer cache settings.</param>
/// <returns>
/// Writer repository.
/// </returns>
private CompositionContainer GetCompositionContainer(WritersCacheSettings settings)
{
CompositionContainer container;
using (var catalog = new AggregateCatalog())
{
foreach (var path in settings.Items)
{
var item = new SafeDirectoryCatalog(path);
catalog.Catalogs.Add(item);
using (var writerWatcher = GetWriterWatcher(path))
{
var addWatcher = _watchers.All(watch => watch.Path != path);
if (addWatcher)
{
_watchers.Add(writerWatcher);
}
}
}
CompositionContainer tempContainer = null;
try
{
tempContainer = new CompositionContainer(catalog);
try
{
tempContainer.ComposeParts(this);
container = tempContainer;
tempContainer = null;
}
catch (CompositionException)
{
throw;
}
}
finally
{
tempContainer?.Dispose();
}
}
return(container);
}
/// <summary>
/// Gets a reference to the cache of available writers.
/// </summary>
/// <param name="settings">Writer cache settings.</param>
/// <returns>
/// A <see cref="T:iTin.Export.ComponentModel.Writer.WritersCache" /> object than represents the available writers-cache.
/// </returns>
public static WritersCache Instance(WritersCacheSettings settings)
{
SentinelHelper.ArgumentNull(settings);
if (_instance != null)
{
return(_instance);
}
lock (SyncLock)
{
if (_instance == null)
{
_instance = new WritersCache(settings);
}
}
return(_instance);
}