Code:
/ Dotnetfx_Win7_3.5.1 / Dotnetfx_Win7_3.5.1 / 3.5.1 / DEVDIV / depot / DevDiv / releases / Orcas / NetFXw7 / ndp / fx / src / DataEntity / System / Data / Common / internal / materialization / coordinator.cs / 1 / coordinator.cs
//------------------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// [....]
// [....]
//-----------------------------------------------------------------------------
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Globalization;
namespace System.Data.Common.Internal.Materialization
{
///
/// A coordinator is responsible for tracking state and processing result in a root or nested query
/// result collection. The coordinator exists within a graph, and knows its Parent, (First)Child,
/// and Next sibling. This allows the Shaper to use the coordinator as a simple state machine when
/// consuming store reader results.
///
internal abstract class Coordinator
{
#region state
///
/// The factory used to generate this coordinator instance. Contains delegates used
/// by the Shaper during result enumeration.
///
internal readonly CoordinatorFactory CoordinatorFactory;
///
/// Parent coordinator (the coordinator producing rows containing this collection).
/// If this is the root, null.
///
internal readonly Coordinator Parent;
///
/// First coordinator for nested results below this collection. When reading a new row
/// for this coordinator, we walk down to the Child.
///
/// NOTE:: this cannot be readonly because we can't know both the parent and the child
/// at initialization time; we set the Child in the parent's constructor.
///
public Coordinator Child
{
get { return _child; }
protected set { _child = value; }
}
private Coordinator _child;
///
/// Next coordinator at this depth. Once we're done consuming results for this reader,
/// we move on to this.Next.
///
internal readonly Coordinator Next;
///
/// Indicates whether data has been read for the collection being aggregated or yielded
/// by this coordinator.
///
public bool IsEntered
{
get { return _isEntered; }
protected set { _isEntered = value; }
}
private bool _isEntered;
///
/// Indicates whether this is the top level coordinator for a query.
///
internal bool IsRoot
{
get { return null == Parent; }
}
#endregion
#region constructor
protected Coordinator(CoordinatorFactory coordinatorFactory, Coordinator parent, Coordinator next)
{
this.CoordinatorFactory = coordinatorFactory;
this.Parent = parent;
this.Next = next;
}
#endregion
#region "public" surface area
///
/// Registers this hierarchy of coordinators in the given shaper.
///
internal void Initialize(Shaper shaper)
{
ResetCollection(shaper);
// Add this coordinator to the appropriate state slot in the
// shaper so that it is available to materialization delegates.
shaper.State[this.CoordinatorFactory.StateSlot] = this;
if (null != this.Child)
{
this.Child.Initialize(shaper);
}
if (null != this.Next)
{
this.Next.Initialize(shaper);
}
}
///
/// Determines the maximum depth of this subtree.
///
internal int MaxDistanceToLeaf()
{
int maxDistance = 0;
Coordinator child = this.Child;
while (null != child)
{
maxDistance = Math.Max(maxDistance, child.MaxDistanceToLeaf() + 1);
child = child.Next;
}
return maxDistance;
}
///
/// This method is called when the current collection is finished and it's time to move to the next collection.
/// Recursively initializes children and siblings as well.
///
internal abstract void ResetCollection(Shaper shaper);
///
/// Precondition: the current row has data for the coordinator.
/// Side-effects: updates keys currently stored in state and updates IsEntered if a new value is encountered.
/// Determines whether the row contains the next element in this collection.
///
internal bool HasNextElement(Shaper shaper)
{
// check if this row contains a new element for this coordinator
bool result = false;
if (!this.IsEntered || !this.CoordinatorFactory.CheckKeys(shaper))
{
// remember initial keys values
this.CoordinatorFactory.SetKeys(shaper);
this.IsEntered = true;
result = true;
}
return result;
}
///
/// Precondition: the current row has data and contains a new element for the coordinator.
/// Reads the next element in this collection.
///
internal abstract void ReadNextElement(Shaper shaper);
#endregion
}
///
/// Typed
internal class Coordinator : Coordinator
{
#region state
internal readonly CoordinatorFactory TypedCoordinatorFactory;
///
/// Exposes the Current element that has been materialized (and is being populated) by this coordinator.
///
internal T Current
{
get { return _current; }
}
private T _current;
///
/// For ObjectResult, aggregates all elements for in the nested collection handled by this coordinator.
///
private List _elements;
///
/// Delegate called when the current nested collection has been consumed. This is necessary in Span
/// scenarios where an EntityCollection RelatedEnd is populated only when all related entities have
/// been materialized.
///
private Action> _handleClose;
///
/// For nested, object-layer coordinators we want to collect all the elements we find and handle them
/// when the root coordinator advances. Otherwise we just want to return them as we find them.
///
private readonly bool IsUsingElementCollection;
#endregion
#region constructors
internal Coordinator(CoordinatorFactory coordinator, Coordinator parent, Coordinator next)
: base(coordinator, parent, next)
{
this.TypedCoordinatorFactory = coordinator;
// generate all children
Coordinator nextChild = null;
foreach (var nestedCoordinator in coordinator.NestedCoordinators.Reverse())
{
// last child processed is first child...
this.Child = nestedCoordinator.CreateCoordinator(this, nextChild);
nextChild = this.Child;
}
this.IsUsingElementCollection = (!this.IsRoot && typeof(T) != typeof(RecordState));
}
#endregion
#region "public" surface area
internal override void ResetCollection(Shaper shaper)
{
// Check to see if anyone has registered for notification when the current coordinator
// is reset.
if (null != _handleClose)
{
_handleClose(shaper, _elements);
_handleClose = null;
}
// Reset is entered for this collection.
this.IsEntered = false;
if (IsUsingElementCollection)
{
_elements = new List();
}
if (null != this.Child)
{
this.Child.ResetCollection(shaper);
}
if (null != this.Next)
{
this.Next.ResetCollection(shaper);
}
}
internal override void ReadNextElement(Shaper shaper)
{
T element;
try
{
element = this.TypedCoordinatorFactory.Element(shaper);
}
catch (Exception e)
{
if (EntityUtil.IsCatchableExceptionType(e))
{
// call a variation of the "Element" delegate with more detailed
// error handling (to produce a better exception message)
element = this.TypedCoordinatorFactory.ElementWithErrorHandling(shaper);
}
// rethrow
throw;
}
if (IsUsingElementCollection)
{
_elements.Add(element);
}
else
{
_current = element;
}
}
///
/// Sets the delegate called when this collection is closed.
///
internal void RegisterCloseHandler(Action> closeHandler)
{
Debug.Assert(null == _handleClose, "more than one handler for a collection close 'event'");
_handleClose = closeHandler;
}
///
/// Called when we're disposing the enumerator;
///
internal void SetCurrentToDefault()
{
_current = default(T);
}
#endregion
#region runtime callable code
// Code in this section is called from the delegates produced by the Translator. It may
// not show up if you search using Find All References
///
/// Returns a handle to the element aggregator for this nested collection.
///
private IEnumerable GetElements()
{
return _elements;
}
#endregion
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//------------------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// [....]
// [....]
//-----------------------------------------------------------------------------
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Globalization;
namespace System.Data.Common.Internal.Materialization
{
///
/// A coordinator is responsible for tracking state and processing result in a root or nested query
/// result collection. The coordinator exists within a graph, and knows its Parent, (First)Child,
/// and Next sibling. This allows the Shaper to use the coordinator as a simple state machine when
/// consuming store reader results.
///
internal abstract class Coordinator
{
#region state
///
/// The factory used to generate this coordinator instance. Contains delegates used
/// by the Shaper during result enumeration.
///
internal readonly CoordinatorFactory CoordinatorFactory;
///
/// Parent coordinator (the coordinator producing rows containing this collection).
/// If this is the root, null.
///
internal readonly Coordinator Parent;
///
/// First coordinator for nested results below this collection. When reading a new row
/// for this coordinator, we walk down to the Child.
///
/// NOTE:: this cannot be readonly because we can't know both the parent and the child
/// at initialization time; we set the Child in the parent's constructor.
///
public Coordinator Child
{
get { return _child; }
protected set { _child = value; }
}
private Coordinator _child;
///
/// Next coordinator at this depth. Once we're done consuming results for this reader,
/// we move on to this.Next.
///
internal readonly Coordinator Next;
///
/// Indicates whether data has been read for the collection being aggregated or yielded
/// by this coordinator.
///
public bool IsEntered
{
get { return _isEntered; }
protected set { _isEntered = value; }
}
private bool _isEntered;
///
/// Indicates whether this is the top level coordinator for a query.
///
internal bool IsRoot
{
get { return null == Parent; }
}
#endregion
#region constructor
protected Coordinator(CoordinatorFactory coordinatorFactory, Coordinator parent, Coordinator next)
{
this.CoordinatorFactory = coordinatorFactory;
this.Parent = parent;
this.Next = next;
}
#endregion
#region "public" surface area
///
/// Registers this hierarchy of coordinators in the given shaper.
///
internal void Initialize(Shaper shaper)
{
ResetCollection(shaper);
// Add this coordinator to the appropriate state slot in the
// shaper so that it is available to materialization delegates.
shaper.State[this.CoordinatorFactory.StateSlot] = this;
if (null != this.Child)
{
this.Child.Initialize(shaper);
}
if (null != this.Next)
{
this.Next.Initialize(shaper);
}
}
///
/// Determines the maximum depth of this subtree.
///
internal int MaxDistanceToLeaf()
{
int maxDistance = 0;
Coordinator child = this.Child;
while (null != child)
{
maxDistance = Math.Max(maxDistance, child.MaxDistanceToLeaf() + 1);
child = child.Next;
}
return maxDistance;
}
///
/// This method is called when the current collection is finished and it's time to move to the next collection.
/// Recursively initializes children and siblings as well.
///
internal abstract void ResetCollection(Shaper shaper);
///
/// Precondition: the current row has data for the coordinator.
/// Side-effects: updates keys currently stored in state and updates IsEntered if a new value is encountered.
/// Determines whether the row contains the next element in this collection.
///
internal bool HasNextElement(Shaper shaper)
{
// check if this row contains a new element for this coordinator
bool result = false;
if (!this.IsEntered || !this.CoordinatorFactory.CheckKeys(shaper))
{
// remember initial keys values
this.CoordinatorFactory.SetKeys(shaper);
this.IsEntered = true;
result = true;
}
return result;
}
///
/// Precondition: the current row has data and contains a new element for the coordinator.
/// Reads the next element in this collection.
///
internal abstract void ReadNextElement(Shaper shaper);
#endregion
}
///
/// Typed
internal class Coordinator : Coordinator
{
#region state
internal readonly CoordinatorFactory TypedCoordinatorFactory;
///
/// Exposes the Current element that has been materialized (and is being populated) by this coordinator.
///
internal T Current
{
get { return _current; }
}
private T _current;
///
/// For ObjectResult, aggregates all elements for in the nested collection handled by this coordinator.
///
private List _elements;
///
/// Delegate called when the current nested collection has been consumed. This is necessary in Span
/// scenarios where an EntityCollection RelatedEnd is populated only when all related entities have
/// been materialized.
///
private Action> _handleClose;
///
/// For nested, object-layer coordinators we want to collect all the elements we find and handle them
/// when the root coordinator advances. Otherwise we just want to return them as we find them.
///
private readonly bool IsUsingElementCollection;
#endregion
#region constructors
internal Coordinator(CoordinatorFactory coordinator, Coordinator parent, Coordinator next)
: base(coordinator, parent, next)
{
this.TypedCoordinatorFactory = coordinator;
// generate all children
Coordinator nextChild = null;
foreach (var nestedCoordinator in coordinator.NestedCoordinators.Reverse())
{
// last child processed is first child...
this.Child = nestedCoordinator.CreateCoordinator(this, nextChild);
nextChild = this.Child;
}
this.IsUsingElementCollection = (!this.IsRoot && typeof(T) != typeof(RecordState));
}
#endregion
#region "public" surface area
internal override void ResetCollection(Shaper shaper)
{
// Check to see if anyone has registered for notification when the current coordinator
// is reset.
if (null != _handleClose)
{
_handleClose(shaper, _elements);
_handleClose = null;
}
// Reset is entered for this collection.
this.IsEntered = false;
if (IsUsingElementCollection)
{
_elements = new List();
}
if (null != this.Child)
{
this.Child.ResetCollection(shaper);
}
if (null != this.Next)
{
this.Next.ResetCollection(shaper);
}
}
internal override void ReadNextElement(Shaper shaper)
{
T element;
try
{
element = this.TypedCoordinatorFactory.Element(shaper);
}
catch (Exception e)
{
if (EntityUtil.IsCatchableExceptionType(e))
{
// call a variation of the "Element" delegate with more detailed
// error handling (to produce a better exception message)
element = this.TypedCoordinatorFactory.ElementWithErrorHandling(shaper);
}
// rethrow
throw;
}
if (IsUsingElementCollection)
{
_elements.Add(element);
}
else
{
_current = element;
}
}
///
/// Sets the delegate called when this collection is closed.
///
internal void RegisterCloseHandler(Action> closeHandler)
{
Debug.Assert(null == _handleClose, "more than one handler for a collection close 'event'");
_handleClose = closeHandler;
}
///
/// Called when we're disposing the enumerator;
///
internal void SetCurrentToDefault()
{
_current = default(T);
}
#endregion
#region runtime callable code
// Code in this section is called from the delegates produced by the Translator. It may
// not show up if you search using Find All References
///
/// Returns a handle to the element aggregator for this nested collection.
///
private IEnumerable GetElements()
{
return _elements;
}
#endregion
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- SendMailErrorEventArgs.cs
- StylusDownEventArgs.cs
- DataBindingExpressionBuilder.cs
- CodeBinaryOperatorExpression.cs
- TextView.cs
- UserUseLicenseDictionaryLoader.cs
- Variable.cs
- KerberosRequestorSecurityToken.cs
- DbConnectionPoolGroup.cs
- DataGridPreparingCellForEditEventArgs.cs
- UIElement3D.cs
- UserPreferenceChangingEventArgs.cs
- CodeComment.cs
- GeneralTransform.cs
- InlineObject.cs
- HtmlForm.cs
- XmlComplianceUtil.cs
- FontCacheUtil.cs
- XmlIncludeAttribute.cs
- Help.cs
- WebControlsSection.cs
- ClientEventManager.cs
- HostedNamedPipeTransportManager.cs
- IIS7WorkerRequest.cs
- IncrementalReadDecoders.cs
- WebEventTraceProvider.cs
- WebBrowserBase.cs
- ZoomPercentageConverter.cs
- StyleSelector.cs
- SiteMapPath.cs
- TdsValueSetter.cs
- Point3DAnimationUsingKeyFrames.cs
- SmtpSection.cs
- TraceFilter.cs
- CollectionCodeDomSerializer.cs
- RemotingService.cs
- BoundField.cs
- WebPartDisplayMode.cs
- HtmlTable.cs
- SymbolType.cs
- GPRECTF.cs
- TransactionsSectionGroup.cs
- DockPatternIdentifiers.cs
- SecurityResources.cs
- TypedCompletedAsyncResult.cs
- RegisteredDisposeScript.cs
- DockPattern.cs
- HybridObjectCache.cs
- ArgumentNullException.cs
- CodeExpressionStatement.cs
- BaseCollection.cs
- SpecialNameAttribute.cs
- Visual3D.cs
- MetaModel.cs
- EntityCommandDefinition.cs
- EntitySetBase.cs
- HtmlWindow.cs
- SqlDataSourceView.cs
- PagesChangedEventArgs.cs
- PeerPresenceInfo.cs
- ListControl.cs
- DataServices.cs
- TextTreePropertyUndoUnit.cs
- DetailsViewPageEventArgs.cs
- XmlSubtreeReader.cs
- EditorZoneBase.cs
- IProducerConsumerCollection.cs
- MultiView.cs
- CryptoApi.cs
- RegionInfo.cs
- WebPartDescriptionCollection.cs
- References.cs
- FontCacheUtil.cs
- FontSizeConverter.cs
- FlowDocumentScrollViewer.cs
- DataControlButton.cs
- NameValuePair.cs
- SettingsAttributeDictionary.cs
- SqlTriggerAttribute.cs
- DbProviderFactoriesConfigurationHandler.cs
- FormCollection.cs
- XmlByteStreamWriter.cs
- VisualProxy.cs
- DateTimeFormatInfo.cs
- WebBrowserBase.cs
- MetadataConversionError.cs
- BamlResourceContent.cs
- XamlContextStack.cs
- CustomError.cs
- SplineKeyFrames.cs
- ZoneIdentityPermission.cs
- ValueCollectionParameterReader.cs
- DataServiceConfiguration.cs
- ADConnectionHelper.cs
- ResourceDescriptionAttribute.cs
- Drawing.cs
- SecurityState.cs
- IdentityReference.cs
- CustomSignedXml.cs
- AttributeEmitter.cs