/// <summary>
/// Increases the total size of the pool by the amount specified.
/// </summary>
/// <param name="increaseBy">The amount of values to increase the pool by.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns></returns>
public async Task IncreasePoolSizeAsync(int increaseBy = 1, CancellationToken cancellationToken = default(CancellationToken))
{
if (IsDisposed || IsDisposing)
{
throw new ObjectDisposedException(this.GetType().Name);
}
if (increaseBy < 0)
{
throw new ArgumentOutOfRangeException(nameof(increaseBy));
}
for (int i = 0; i < increaseBy; i++)
{
cancellationToken.ThrowIfCancellationRequested();
var instance = await Task.Run(() => InstanceBuilder.Invoke(cancellationToken), cancellationToken).ConfigureAwait(false);
await Task.Run(() =>
{
PooledInstances.Enqueue(instance);
}, cancellationToken).ConfigureAwait(false);
Interlocked.Increment(ref _totalInstancesCount);
RaisePropertyChanged(nameof(TotalInstancesCount));
}
}
/// <summary>
/// Acquires the next available pooled value.
/// </summary>
/// <param name="pooledValueAcquisitionMode">The pooled value acquisition mode.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns></returns>
public async Task <Pooled <TValue> > AcquirePooledValueAsync(
PooledValueAcquisitionMode pooledValueAcquisitionMode = PooledValueAcquisitionMode.AvailableInstanceOrDefaultValue,
CancellationToken cancellationToken = default(CancellationToken))
{
if (IsDisposed || IsDisposing)
{
throw new ObjectDisposedException(this.GetType().Name);
}
TValue value = default(TValue);
// check whether we actually currently have any instances left
if (PooledInstances.IsEmpty)
{
if (pooledValueAcquisitionMode == PooledValueAcquisitionMode.AvailableInstanceOrDefaultValue)
{
return(default(Pooled <TValue>));
}
else if (pooledValueAcquisitionMode == PooledValueAcquisitionMode.AvailableInstanceOrCreateNewOne)
{
try
{
value = await Task.Run(() => InstanceBuilder.Invoke(cancellationToken), cancellationToken).ConfigureAwait(false);
}
catch (TargetInvocationException targetInvocationException)
{
targetInvocationException.InnerException.ThrowIfNotNull();
}
}
else
{
while (PooledInstances.IsEmpty || PooledInstances.TryDequeue(out value) == false)
{
cancellationToken.ThrowIfCancellationRequested();
await Task.Yield();
}
}
}
else
{
// try to retrieve the next available / queued value
if (PooledInstances.TryDequeue(out value) == false)
{
if (pooledValueAcquisitionMode == PooledValueAcquisitionMode.AvailableInstanceOrDefaultValue)
{
return(default(Pooled <TValue>));
}
else if (pooledValueAcquisitionMode == PooledValueAcquisitionMode.AvailableInstanceOrCreateNewOne) // build a new one
{
try
{
value = await Task.Run(() => InstanceBuilder.Invoke(cancellationToken), cancellationToken).ConfigureAwait(false);
}
catch (TargetInvocationException targetInvocationException)
{
targetInvocationException.InnerException.ThrowIfNotNull();
}
}
else
{
// keep trying
while (PooledInstances.TryDequeue(out value) == false)
{
cancellationToken.ThrowIfCancellationRequested();
await Task.Yield();
}
}
}
}
RaisePropertyChanged(nameof(AvailableInstancesCount));
cancellationToken.ThrowIfCancellationRequested();
return(new Pooled <TValue>(value, this));
}