/// <summary>
/// Loads requested data from associated IDataSource and supplies an object containing data to be used by associated IDataSource
/// </summary>
/// <param name="inputParameters">Input parameters for IDataSource</param>
/// <param name="dataToLoad">List of types of data that should be loaded</param>
/// <param name="stopAfterFirstException">If true, will stop loading after catching first exception</param>
/// <param name="callerContext">Object containing data to be used by associated IDataSource</param>
/// <returns>Requested data, grouped by type</returns>
public LoadingResult <TData> LoadData(IDictionary <TParam, object> inputParameters, TData[] dataToLoad, bool stopAfterFirstException, object callerContext)
{
var startTime = DateTime.Now;
Debug.WriteLine("Loading {0}", String.Join(", ", dataToLoad));
var parameters = new Dictionary <TParam, object>(inputParameters);
var data = new LoadingResult <TData> {
Success = true
};
foreach (var dataType in dataToLoad)
{
var type = dataType;
ThreadPool.QueueUserWorkItem(state => LoadData(type, parameters, data, state), callerContext);
}
lock (data)
{
while ((!stopAfterFirstException || (stopAfterFirstException && data.Success)) && (data.Count < dataToLoad.Length))
{
Monitor.Wait(data);
}
}
Debug.WriteLine("Loading finished in {0}", DateTime.Now - startTime);
return(data);
}
private void LoadData(TData data, IDictionary <TParam, object> parameters, LoadingResult <TData> dataContainer, object callerContext)
{
var startTime = DateTime.Now;
Debug.WriteLine("Will load {0}", data);
var inputParameters = GetInputParameters(data);
var parameterValues = new Dictionary <TParam, object>();
lock (parameters)
{
bool allParametersExist;
do
{
allParametersExist = true;
parameterValues.Clear();
foreach (var paramType in inputParameters)
{
if (parameterValues.ContainsKey(paramType))
{
continue;
}
object paramVal;
if (parameters.TryGetValue(paramType, out paramVal))
{
parameterValues.Add(paramType, paramVal);
}
else
{
Debug.WriteLine("[{0}] Required parameter {1} does not exist", data, paramType);
allParametersExist = false;
}
}
if (!allParametersExist)
{
Monitor.Wait(parameters);
}
} while (!allParametersExist);
}
Debug.WriteLine("[{0}] All required parameters do exist", data);
foreach (var paramType in GetOptionalParameters(data))
{
if (parameterValues.ContainsKey(paramType))
{
continue;
}
object paramVal;
if (parameters.TryGetValue(paramType, out paramVal))
{
Debug.WriteLine("[{0}] Optional parameter {1} is supplied", data, paramType);
parameterValues.Add(paramType, paramVal);
}
}
object dataValue = null;
try
{
dataValue = _dataSource.LoadData(data, parameterValues, new LoadingContext <TParam>(parameters)
{
State = callerContext
});
lock (dataContainer)
{
dataContainer.AddData(data, dataValue);
Monitor.Pulse(dataContainer);
}
}
catch (Exception ex)
{
lock (dataContainer)
{
dataContainer.AddData(data, null);
dataContainer.Success = false;
dataContainer.AddException(ex);
Monitor.Pulse(dataContainer);
}
}
Debug.WriteLine("[{0}] Loading finished in {1}", data, DateTime.Now - startTime);
}
