ActivityExecutionContextCollection.cs source code in C# .NET

Source code for the .NET framework in C#

                        

Code:

/ 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / cdf / src / WF / Common / AuthoringOM / ActivityExecutionContextCollection.cs / 1305376 / ActivityExecutionContextCollection.cs

                            #pragma warning disable 1634, 1691 

namespace System.Workflow.ComponentModel
{
    #region Imports 

    using System; 
    using System.Diagnostics; 
    using System.Collections;
    using System.Collections.Generic; 
    using System.Collections.ObjectModel;
    using System.Workflow.ComponentModel.Design;
    using System.Runtime.Serialization;
    using System.IO; 
    using System.Runtime.Serialization.Formatters.Binary;
    using System.Workflow.ComponentModel.Serialization; 
    #endregion 

    public sealed class ActivityExecutionContextManager 
    {
        #region Data members and constructor

        private ActivityExecutionContext ownerContext = null; 
        private List executionContexts = new List();
 
        internal ActivityExecutionContextManager(ActivityExecutionContext ownerContext) 
        {
            this.ownerContext = ownerContext; 

            // Populate the child collection.
            IList activeContexts = (IList)this.ownerContext.Activity.ContextActivity.GetValue(Activity.ActiveExecutionContextsProperty);
            if (activeContexts != null) 
            {
                foreach (Activity activeContextActivity in activeContexts) 
                    this.executionContexts.Add(new ActivityExecutionContext(activeContextActivity)); 
            }
        } 

        #endregion

        #region Public members 

        public ReadOnlyCollection ExecutionContexts 
        { 
            get
            { 
                if (this.ownerContext == null)
#pragma warning suppress 56503
                    throw new ObjectDisposedException("ActivityExecutionContextManager");
 
                    return new ReadOnlyCollection(this.executionContexts);
            } 
        } 

        public ActivityExecutionContext CreateExecutionContext(Activity activity) 
        {
            if (this.ownerContext == null)
                throw new ObjectDisposedException("ActivityExecutionContextManager");
 
            if (activity == null)
                throw new ArgumentNullException("activity"); 
 
            if (!this.ownerContext.IsValidChild(activity, true))
                throw new ArgumentException(SR.GetString(SR.AEC_InvalidActivity), "activity"); 

            Activity copiedActivity = activity.Clone();
            ((IDependencyObjectAccessor)copiedActivity).InitializeInstanceForRuntime(this.ownerContext.Activity.WorkflowCoreRuntime);
 
            //Reset the cloned tree for execution.
            Queue activityQueue = new Queue(); 
            activityQueue.Enqueue(copiedActivity); 

            while (activityQueue.Count != 0) 
            {
                Activity clonedActivity = activityQueue.Dequeue();
                if (clonedActivity.ExecutionStatus != ActivityExecutionStatus.Initialized)
                { 
                    clonedActivity.ResetAllKnownDependencyProperties();
                    CompositeActivity compositeActivity = clonedActivity as CompositeActivity; 
 
                    if (compositeActivity != null)
                    { 
                        for (int i = 0; i < compositeActivity.EnabledActivities.Count; ++i)
                        {
                            activityQueue.Enqueue(compositeActivity.EnabledActivities[i]);
                        } 

                        ISupportAlternateFlow alternateFlow = compositeActivity as ISupportAlternateFlow; 
 
                        if(alternateFlow != null)
                        { 
                            for (int i = 0; i < alternateFlow.AlternateFlowActivities.Count; ++i)
                            {
                                activityQueue.Enqueue(alternateFlow.AlternateFlowActivities[i]);
                            } 
                        }
                    } 
                } 
            }
 
            // get active context activities and add it to this one
            IList activeContexts = (IList)this.ownerContext.Activity.ContextActivity.GetValue(Activity.ActiveExecutionContextsProperty);
            if (activeContexts == null)
            { 
                activeContexts = new List();
                this.ownerContext.Activity.ContextActivity.SetValue(Activity.ActiveExecutionContextsProperty, activeContexts); 
            } 
            activeContexts.Add(copiedActivity);
 
            // prepare the copied activity as a context activity
            ActivityExecutionContextInfo contextInfo = new ActivityExecutionContextInfo(activity.QualifiedName, this.ownerContext.WorkflowCoreRuntime.GetNewContextActivityId(), Guid.NewGuid(), this.ownerContext.ContextId);
            copiedActivity.SetValue(Activity.ActivityExecutionContextInfoProperty, contextInfo);
            copiedActivity.SetValue(Activity.ActivityContextGuidProperty, contextInfo.ContextGuid); 
            ActivityExecutionContext newExecutionContext = null;
            try 
            { 
                // inform workflow runtime
                this.ownerContext.Activity.WorkflowCoreRuntime.RegisterContextActivity(copiedActivity); 

                // return the new context
                newExecutionContext = new ActivityExecutionContext(copiedActivity);
                this.executionContexts.Add(newExecutionContext); 
                newExecutionContext.InitializeActivity(newExecutionContext.Activity);
                return newExecutionContext; 
            } 
            catch(Exception)
            { 
                if (newExecutionContext != null)
                {
                    this.CompleteExecutionContext(newExecutionContext);
                } 
                else
                { 
                    activeContexts.Remove(copiedActivity); 
                }
                throw; 
            }
        }

        public void CompleteExecutionContext(ActivityExecutionContext childContext) 
        {
            if (this.ownerContext == null) 
                throw new ObjectDisposedException("ActivityExecutionContextManager"); 

            CompleteExecutionContext(childContext, false); 
        }

        public void CompleteExecutionContext(ActivityExecutionContext childContext, bool forcePersist)
        { 
            if (this.ownerContext == null)
                throw new ObjectDisposedException("ActivityExecutionContextManager"); 
 
            if (childContext == null)
                throw new ArgumentNullException("childContext"); 

            if (childContext.Activity == null)
                throw new ArgumentException("childContext", SR.GetString(SR.Error_MissingActivityProperty));
 
            if (childContext.Activity.ContextActivity == null)
                throw new ArgumentException("childContext", SR.GetString(SR.Error_MissingContextActivityProperty)); 
 
            if (!this.executionContexts.Contains(childContext))
                throw new ArgumentException(); 

            if (childContext.Activity.ContextActivity.ExecutionStatus != ActivityExecutionStatus.Closed && childContext.Activity.ContextActivity.ExecutionStatus != ActivityExecutionStatus.Initialized)
                throw new InvalidOperationException(SR.GetString(System.Globalization.CultureInfo.CurrentCulture, SR.Error_CannotCompleteContext));
 
            // make sure that this is in the active contexts collections
            ActivityExecutionContextInfo childContextInfo = childContext.Activity.ContextActivity.GetValue(Activity.ActivityExecutionContextInfoProperty) as ActivityExecutionContextInfo; 
            IList activeContexts = (IList)this.ownerContext.Activity.ContextActivity.GetValue(Activity.ActiveExecutionContextsProperty); 
            if (activeContexts == null || !activeContexts.Contains(childContext.Activity.ContextActivity))
                throw new ArgumentException(); 

            // add it to completed contexts collection
            bool needsCompensation = childContext.Activity.NeedsCompensation;
            if (needsCompensation || forcePersist) 
            {
                // add it to completed contexts 
                List completedContexts = this.ownerContext.Activity.ContextActivity.GetValue(Activity.CompletedExecutionContextsProperty) as List; 
                if (completedContexts == null)
                { 
                    completedContexts = new List();
                    this.ownerContext.Activity.ContextActivity.SetValue(Activity.CompletedExecutionContextsProperty, completedContexts);
                }
 
                if (needsCompensation)
                    childContextInfo.Flags = PersistFlags.NeedsCompensation; 
                if (forcePersist) 
                    childContextInfo.Flags |= PersistFlags.ForcePersist;
 
                childContextInfo.SetCompletedOrderId(this.ownerContext.Activity.IncrementCompletedOrderId());
                completedContexts.Add(childContextInfo);

                // ask runtime to save the context activity 
                this.ownerContext.Activity.WorkflowCoreRuntime.SaveContextActivity(childContext.Activity);
            } 
 
            // remove it from active contexts
            activeContexts.Remove(childContext.Activity.ContextActivity); 
            this.executionContexts.Remove(childContext);

            //Case for those context which has compensatable child context, when those context
            //are completed at the end of Compensation chain we need to uninitialize the context 
            //activity associated to them.
            if (childContext.Activity.ContextActivity.CanUninitializeNow && childContext.Activity.ContextActivity.ExecutionResult != ActivityExecutionResult.Uninitialized) 
            { 
                childContext.Activity.ContextActivity.Uninitialize(this.ownerContext.Activity.RootActivity.WorkflowCoreRuntime);
                childContext.Activity.ContextActivity.SetValue(Activity.ExecutionResultProperty, ActivityExecutionResult.Uninitialized); 
            }

            // unregister it from runtime
            this.ownerContext.Activity.WorkflowCoreRuntime.UnregisterContextActivity(childContext.Activity); 

            if (!(needsCompensation || forcePersist)) 
            { 
                childContext.Activity.Dispose();
            } 
        }

        public ActivityExecutionContext GetExecutionContext(Activity activity)
        { 
            if (this.ownerContext == null)
                throw new ObjectDisposedException("ActivityExecutionContextManager"); 
 
            if (activity == null)
                throw new ArgumentNullException("activity"); 

            ActivityExecutionContextInfo contextInfo = activity.GetValue(Activity.ActivityExecutionContextInfoProperty) as ActivityExecutionContextInfo;

            // Returns the first context for an activity with the same qualified name. 
            foreach (ActivityExecutionContext context in ExecutionContexts)
            { 
                if (contextInfo == null) //Template being passed. 
                {
                    if (context.Activity.ContextActivity.QualifiedName == activity.QualifiedName) 
                        return context;
                }
                else //Context Sensitive Activity
                { 
                    if (context.ContextGuid.Equals(contextInfo.ContextGuid))
                        return context; 
                } 
            }
            return null; 
        }

        public IEnumerable PersistedExecutionContexts
        { 
            get
            { 
                if (this.ownerContext == null) 
#pragma warning suppress 56503
                    throw new ObjectDisposedException("ActivityExecutionContextManager"); 

                List completedContexts = this.ownerContext.Activity.ContextActivity.GetValue(Activity.CompletedExecutionContextsProperty) as List;
                completedContexts = (completedContexts == null) ? new List() : completedContexts;
 
                List persistedContexts = new List();
                foreach (ActivityExecutionContextInfo contextInfo in completedContexts) 
                    if ((contextInfo.Flags & PersistFlags.ForcePersist) != 0) 
                        persistedContexts.Add(contextInfo.ContextGuid);
 
                return persistedContexts;
            }
        }
 
        public ActivityExecutionContext GetPersistedExecutionContext(Guid contextGuid)
        { 
            if (this.ownerContext == null) 
                throw new ObjectDisposedException("ActivityExecutionContextManager");
 
            // Check if child execution context exists.
            IList completedContexts = this.ownerContext.Activity.ContextActivity.GetValue(Activity.CompletedExecutionContextsProperty) as IList;
            if (completedContexts == null)
                throw new ArgumentException(); 

            ActivityExecutionContextInfo contextInfo = null; 
            foreach (ActivityExecutionContextInfo completedContextInfo in completedContexts) 
            {
                if (completedContextInfo.ContextGuid == contextGuid && ((completedContextInfo.Flags & PersistFlags.ForcePersist) != 0)) 
                {
                    contextInfo = completedContextInfo;
                    break;
                } 
            }
 
            if (contextInfo == null) 
                throw new ArgumentException();
 
            // The caller would have to close the AEC with forcepersist the next time
            // around.
            contextInfo.Flags &= ~PersistFlags.ForcePersist;
            return DiscardPersistedExecutionContext(contextInfo); 
        }
 
        #endregion 

        internal void Dispose() 
        {
            if (this.ownerContext != null)
            {
                foreach (ActivityExecutionContext executionContext in this.ExecutionContexts) 
                    ((IDisposable)executionContext).Dispose();
                this.ownerContext = null; 
            } 
        }
 
        #region Internal members

        internal ReadOnlyCollection CompletedExecutionContexts
        { 
            get
            { 
                List completedContexts = this.ownerContext.Activity.ContextActivity.GetValue(Activity.CompletedExecutionContextsProperty) as List; 
                completedContexts = (completedContexts == null) ? new List() : completedContexts;
                return completedContexts.AsReadOnly(); 
            }
        }

        internal ActivityExecutionContext DiscardPersistedExecutionContext(ActivityExecutionContextInfo contextInfo) 
        {
            if (contextInfo == null) 
                throw new ArgumentNullException("contextInfo"); 

            // check if child execution context 
            IList completedContexts = this.ownerContext.Activity.ContextActivity.GetValue(Activity.CompletedExecutionContextsProperty) as IList;
            if (completedContexts == null || !completedContexts.Contains(contextInfo))
                throw new ArgumentException();
 
            // revoke from persistence service
            Activity revokedActivity = this.ownerContext.WorkflowCoreRuntime.LoadContextActivity(contextInfo, this.ownerContext.Activity.ContextActivity.GetActivityByName(contextInfo.ActivityQualifiedName)); 
            ((IDependencyObjectAccessor)revokedActivity).InitializeInstanceForRuntime(this.ownerContext.Activity.WorkflowCoreRuntime); 

            // add it back to active contexts 
            IList activeContexts = (IList)this.ownerContext.Activity.ContextActivity.GetValue(Activity.ActiveExecutionContextsProperty);
            if (activeContexts == null)
            {
                activeContexts = new List(); 
                this.ownerContext.Activity.ContextActivity.SetValue(Activity.ActiveExecutionContextsProperty, activeContexts);
            } 
            activeContexts.Add(revokedActivity); 

            // inform workflow runtime 
            this.ownerContext.Activity.WorkflowCoreRuntime.RegisterContextActivity(revokedActivity);

            // return the new context
            ActivityExecutionContext revokedContext = new ActivityExecutionContext(revokedActivity); 
            this.executionContexts.Add(revokedContext);
            System.Workflow.Runtime.WorkflowTrace.Runtime.TraceEvent(TraceEventType.Information, 0, "Revoking context {0}:{1}", revokedContext.ContextId, revokedContext.Activity.ContextActivity.QualifiedName); 
 
            // remove it from completed contexts
            completedContexts.Remove(contextInfo); 
            return revokedContext;
        }

        #endregion 
    }
 
    #region Class ActivityExecutionContextInfo 

    [Serializable] 
    [Flags]
    internal enum PersistFlags : byte
    {
        NeedsCompensation = 1, 
        ForcePersist = 2
    } 
 
    [Serializable]
    internal sealed class ActivityExecutionContextInfo 
    {
        private string qualifiedID = string.Empty;
        private int contextId = -1;
        private Guid contextGuid = Guid.Empty; // 
        private int parentContextId = -1;
        private int completedOrderId = -1; 
        private PersistFlags flags = 0; 

        internal ActivityExecutionContextInfo(string qualifiedName, int contextId, Guid contextGuid, int parentContextId) 
        {
            this.qualifiedID = qualifiedName;
            this.contextId = contextId;
            this.contextGuid = contextGuid; 
            this.parentContextId = parentContextId;
        } 
 
        internal int ContextId
        { 
            get
            {
                return this.contextId;
            } 
        }
 
        public Guid ContextGuid 
        {
            get 
            {
                return this.contextGuid;
            }
        } 

        public string ActivityQualifiedName 
        { 
            get
            { 
                return this.qualifiedID;
            }
        }
 
        public int CompletedOrderId
        { 
            get 
            {
                return this.completedOrderId; 
            }
        }

        internal int ParentContextId 
        {
            get 
            { 
                return this.parentContextId;
            } 
        }

        internal void SetCompletedOrderId(int completedOrderId)
        { 
            this.completedOrderId = completedOrderId;
        } 
 
        internal PersistFlags Flags
        { 
            get
            {
                return this.flags;
            } 

            set 
            { 
                this.flags = value;
            } 
        }

        public override int GetHashCode()
        { 
            return contextGuid.GetHashCode();
        } 
 
        public override bool Equals(object obj)
        { 
            ActivityExecutionContextInfo otherContextInfo = obj as ActivityExecutionContextInfo;

            if (otherContextInfo != null)
            { 
                return this.ContextGuid.Equals(otherContextInfo.ContextGuid);
            } 
            return false; 
        }
    } 

    #endregion
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
#pragma warning disable 1634, 1691 

namespace System.Workflow.ComponentModel
{
    #region Imports 

    using System; 
    using System.Diagnostics; 
    using System.Collections;
    using System.Collections.Generic; 
    using System.Collections.ObjectModel;
    using System.Workflow.ComponentModel.Design;
    using System.Runtime.Serialization;
    using System.IO; 
    using System.Runtime.Serialization.Formatters.Binary;
    using System.Workflow.ComponentModel.Serialization; 
    #endregion 

    public sealed class ActivityExecutionContextManager 
    {
        #region Data members and constructor

        private ActivityExecutionContext ownerContext = null; 
        private List executionContexts = new List();
 
        internal ActivityExecutionContextManager(ActivityExecutionContext ownerContext) 
        {
            this.ownerContext = ownerContext; 

            // Populate the child collection.
            IList activeContexts = (IList)this.ownerContext.Activity.ContextActivity.GetValue(Activity.ActiveExecutionContextsProperty);
            if (activeContexts != null) 
            {
                foreach (Activity activeContextActivity in activeContexts) 
                    this.executionContexts.Add(new ActivityExecutionContext(activeContextActivity)); 
            }
        } 

        #endregion

        #region Public members 

        public ReadOnlyCollection ExecutionContexts 
        { 
            get
            { 
                if (this.ownerContext == null)
#pragma warning suppress 56503
                    throw new ObjectDisposedException("ActivityExecutionContextManager");
 
                    return new ReadOnlyCollection(this.executionContexts);
            } 
        } 

        public ActivityExecutionContext CreateExecutionContext(Activity activity) 
        {
            if (this.ownerContext == null)
                throw new ObjectDisposedException("ActivityExecutionContextManager");
 
            if (activity == null)
                throw new ArgumentNullException("activity"); 
 
            if (!this.ownerContext.IsValidChild(activity, true))
                throw new ArgumentException(SR.GetString(SR.AEC_InvalidActivity), "activity"); 

            Activity copiedActivity = activity.Clone();
            ((IDependencyObjectAccessor)copiedActivity).InitializeInstanceForRuntime(this.ownerContext.Activity.WorkflowCoreRuntime);
 
            //Reset the cloned tree for execution.
            Queue activityQueue = new Queue(); 
            activityQueue.Enqueue(copiedActivity); 

            while (activityQueue.Count != 0) 
            {
                Activity clonedActivity = activityQueue.Dequeue();
                if (clonedActivity.ExecutionStatus != ActivityExecutionStatus.Initialized)
                { 
                    clonedActivity.ResetAllKnownDependencyProperties();
                    CompositeActivity compositeActivity = clonedActivity as CompositeActivity; 
 
                    if (compositeActivity != null)
                    { 
                        for (int i = 0; i < compositeActivity.EnabledActivities.Count; ++i)
                        {
                            activityQueue.Enqueue(compositeActivity.EnabledActivities[i]);
                        } 

                        ISupportAlternateFlow alternateFlow = compositeActivity as ISupportAlternateFlow; 
 
                        if(alternateFlow != null)
                        { 
                            for (int i = 0; i < alternateFlow.AlternateFlowActivities.Count; ++i)
                            {
                                activityQueue.Enqueue(alternateFlow.AlternateFlowActivities[i]);
                            } 
                        }
                    } 
                } 
            }
 
            // get active context activities and add it to this one
            IList activeContexts = (IList)this.ownerContext.Activity.ContextActivity.GetValue(Activity.ActiveExecutionContextsProperty);
            if (activeContexts == null)
            { 
                activeContexts = new List();
                this.ownerContext.Activity.ContextActivity.SetValue(Activity.ActiveExecutionContextsProperty, activeContexts); 
            } 
            activeContexts.Add(copiedActivity);
 
            // prepare the copied activity as a context activity
            ActivityExecutionContextInfo contextInfo = new ActivityExecutionContextInfo(activity.QualifiedName, this.ownerContext.WorkflowCoreRuntime.GetNewContextActivityId(), Guid.NewGuid(), this.ownerContext.ContextId);
            copiedActivity.SetValue(Activity.ActivityExecutionContextInfoProperty, contextInfo);
            copiedActivity.SetValue(Activity.ActivityContextGuidProperty, contextInfo.ContextGuid); 
            ActivityExecutionContext newExecutionContext = null;
            try 
            { 
                // inform workflow runtime
                this.ownerContext.Activity.WorkflowCoreRuntime.RegisterContextActivity(copiedActivity); 

                // return the new context
                newExecutionContext = new ActivityExecutionContext(copiedActivity);
                this.executionContexts.Add(newExecutionContext); 
                newExecutionContext.InitializeActivity(newExecutionContext.Activity);
                return newExecutionContext; 
            } 
            catch(Exception)
            { 
                if (newExecutionContext != null)
                {
                    this.CompleteExecutionContext(newExecutionContext);
                } 
                else
                { 
                    activeContexts.Remove(copiedActivity); 
                }
                throw; 
            }
        }

        public void CompleteExecutionContext(ActivityExecutionContext childContext) 
        {
            if (this.ownerContext == null) 
                throw new ObjectDisposedException("ActivityExecutionContextManager"); 

            CompleteExecutionContext(childContext, false); 
        }

        public void CompleteExecutionContext(ActivityExecutionContext childContext, bool forcePersist)
        { 
            if (this.ownerContext == null)
                throw new ObjectDisposedException("ActivityExecutionContextManager"); 
 
            if (childContext == null)
                throw new ArgumentNullException("childContext"); 

            if (childContext.Activity == null)
                throw new ArgumentException("childContext", SR.GetString(SR.Error_MissingActivityProperty));
 
            if (childContext.Activity.ContextActivity == null)
                throw new ArgumentException("childContext", SR.GetString(SR.Error_MissingContextActivityProperty)); 
 
            if (!this.executionContexts.Contains(childContext))
                throw new ArgumentException(); 

            if (childContext.Activity.ContextActivity.ExecutionStatus != ActivityExecutionStatus.Closed && childContext.Activity.ContextActivity.ExecutionStatus != ActivityExecutionStatus.Initialized)
                throw new InvalidOperationException(SR.GetString(System.Globalization.CultureInfo.CurrentCulture, SR.Error_CannotCompleteContext));
 
            // make sure that this is in the active contexts collections
            ActivityExecutionContextInfo childContextInfo = childContext.Activity.ContextActivity.GetValue(Activity.ActivityExecutionContextInfoProperty) as ActivityExecutionContextInfo; 
            IList activeContexts = (IList)this.ownerContext.Activity.ContextActivity.GetValue(Activity.ActiveExecutionContextsProperty); 
            if (activeContexts == null || !activeContexts.Contains(childContext.Activity.ContextActivity))
                throw new ArgumentException(); 

            // add it to completed contexts collection
            bool needsCompensation = childContext.Activity.NeedsCompensation;
            if (needsCompensation || forcePersist) 
            {
                // add it to completed contexts 
                List completedContexts = this.ownerContext.Activity.ContextActivity.GetValue(Activity.CompletedExecutionContextsProperty) as List; 
                if (completedContexts == null)
                { 
                    completedContexts = new List();
                    this.ownerContext.Activity.ContextActivity.SetValue(Activity.CompletedExecutionContextsProperty, completedContexts);
                }
 
                if (needsCompensation)
                    childContextInfo.Flags = PersistFlags.NeedsCompensation; 
                if (forcePersist) 
                    childContextInfo.Flags |= PersistFlags.ForcePersist;
 
                childContextInfo.SetCompletedOrderId(this.ownerContext.Activity.IncrementCompletedOrderId());
                completedContexts.Add(childContextInfo);

                // ask runtime to save the context activity 
                this.ownerContext.Activity.WorkflowCoreRuntime.SaveContextActivity(childContext.Activity);
            } 
 
            // remove it from active contexts
            activeContexts.Remove(childContext.Activity.ContextActivity); 
            this.executionContexts.Remove(childContext);

            //Case for those context which has compensatable child context, when those context
            //are completed at the end of Compensation chain we need to uninitialize the context 
            //activity associated to them.
            if (childContext.Activity.ContextActivity.CanUninitializeNow && childContext.Activity.ContextActivity.ExecutionResult != ActivityExecutionResult.Uninitialized) 
            { 
                childContext.Activity.ContextActivity.Uninitialize(this.ownerContext.Activity.RootActivity.WorkflowCoreRuntime);
                childContext.Activity.ContextActivity.SetValue(Activity.ExecutionResultProperty, ActivityExecutionResult.Uninitialized); 
            }

            // unregister it from runtime
            this.ownerContext.Activity.WorkflowCoreRuntime.UnregisterContextActivity(childContext.Activity); 

            if (!(needsCompensation || forcePersist)) 
            { 
                childContext.Activity.Dispose();
            } 
        }

        public ActivityExecutionContext GetExecutionContext(Activity activity)
        { 
            if (this.ownerContext == null)
                throw new ObjectDisposedException("ActivityExecutionContextManager"); 
 
            if (activity == null)
                throw new ArgumentNullException("activity"); 

            ActivityExecutionContextInfo contextInfo = activity.GetValue(Activity.ActivityExecutionContextInfoProperty) as ActivityExecutionContextInfo;

            // Returns the first context for an activity with the same qualified name. 
            foreach (ActivityExecutionContext context in ExecutionContexts)
            { 
                if (contextInfo == null) //Template being passed. 
                {
                    if (context.Activity.ContextActivity.QualifiedName == activity.QualifiedName) 
                        return context;
                }
                else //Context Sensitive Activity
                { 
                    if (context.ContextGuid.Equals(contextInfo.ContextGuid))
                        return context; 
                } 
            }
            return null; 
        }

        public IEnumerable PersistedExecutionContexts
        { 
            get
            { 
                if (this.ownerContext == null) 
#pragma warning suppress 56503
                    throw new ObjectDisposedException("ActivityExecutionContextManager"); 

                List completedContexts = this.ownerContext.Activity.ContextActivity.GetValue(Activity.CompletedExecutionContextsProperty) as List;
                completedContexts = (completedContexts == null) ? new List() : completedContexts;
 
                List persistedContexts = new List();
                foreach (ActivityExecutionContextInfo contextInfo in completedContexts) 
                    if ((contextInfo.Flags & PersistFlags.ForcePersist) != 0) 
                        persistedContexts.Add(contextInfo.ContextGuid);
 
                return persistedContexts;
            }
        }
 
        public ActivityExecutionContext GetPersistedExecutionContext(Guid contextGuid)
        { 
            if (this.ownerContext == null) 
                throw new ObjectDisposedException("ActivityExecutionContextManager");
 
            // Check if child execution context exists.
            IList completedContexts = this.ownerContext.Activity.ContextActivity.GetValue(Activity.CompletedExecutionContextsProperty) as IList;
            if (completedContexts == null)
                throw new ArgumentException(); 

            ActivityExecutionContextInfo contextInfo = null; 
            foreach (ActivityExecutionContextInfo completedContextInfo in completedContexts) 
            {
                if (completedContextInfo.ContextGuid == contextGuid && ((completedContextInfo.Flags & PersistFlags.ForcePersist) != 0)) 
                {
                    contextInfo = completedContextInfo;
                    break;
                } 
            }
 
            if (contextInfo == null) 
                throw new ArgumentException();
 
            // The caller would have to close the AEC with forcepersist the next time
            // around.
            contextInfo.Flags &= ~PersistFlags.ForcePersist;
            return DiscardPersistedExecutionContext(contextInfo); 
        }
 
        #endregion 

        internal void Dispose() 
        {
            if (this.ownerContext != null)
            {
                foreach (ActivityExecutionContext executionContext in this.ExecutionContexts) 
                    ((IDisposable)executionContext).Dispose();
                this.ownerContext = null; 
            } 
        }
 
        #region Internal members

        internal ReadOnlyCollection CompletedExecutionContexts
        { 
            get
            { 
                List completedContexts = this.ownerContext.Activity.ContextActivity.GetValue(Activity.CompletedExecutionContextsProperty) as List; 
                completedContexts = (completedContexts == null) ? new List() : completedContexts;
                return completedContexts.AsReadOnly(); 
            }
        }

        internal ActivityExecutionContext DiscardPersistedExecutionContext(ActivityExecutionContextInfo contextInfo) 
        {
            if (contextInfo == null) 
                throw new ArgumentNullException("contextInfo"); 

            // check if child execution context 
            IList completedContexts = this.ownerContext.Activity.ContextActivity.GetValue(Activity.CompletedExecutionContextsProperty) as IList;
            if (completedContexts == null || !completedContexts.Contains(contextInfo))
                throw new ArgumentException();
 
            // revoke from persistence service
            Activity revokedActivity = this.ownerContext.WorkflowCoreRuntime.LoadContextActivity(contextInfo, this.ownerContext.Activity.ContextActivity.GetActivityByName(contextInfo.ActivityQualifiedName)); 
            ((IDependencyObjectAccessor)revokedActivity).InitializeInstanceForRuntime(this.ownerContext.Activity.WorkflowCoreRuntime); 

            // add it back to active contexts 
            IList activeContexts = (IList)this.ownerContext.Activity.ContextActivity.GetValue(Activity.ActiveExecutionContextsProperty);
            if (activeContexts == null)
            {
                activeContexts = new List(); 
                this.ownerContext.Activity.ContextActivity.SetValue(Activity.ActiveExecutionContextsProperty, activeContexts);
            } 
            activeContexts.Add(revokedActivity); 

            // inform workflow runtime 
            this.ownerContext.Activity.WorkflowCoreRuntime.RegisterContextActivity(revokedActivity);

            // return the new context
            ActivityExecutionContext revokedContext = new ActivityExecutionContext(revokedActivity); 
            this.executionContexts.Add(revokedContext);
            System.Workflow.Runtime.WorkflowTrace.Runtime.TraceEvent(TraceEventType.Information, 0, "Revoking context {0}:{1}", revokedContext.ContextId, revokedContext.Activity.ContextActivity.QualifiedName); 
 
            // remove it from completed contexts
            completedContexts.Remove(contextInfo); 
            return revokedContext;
        }

        #endregion 
    }
 
    #region Class ActivityExecutionContextInfo 

    [Serializable] 
    [Flags]
    internal enum PersistFlags : byte
    {
        NeedsCompensation = 1, 
        ForcePersist = 2
    } 
 
    [Serializable]
    internal sealed class ActivityExecutionContextInfo 
    {
        private string qualifiedID = string.Empty;
        private int contextId = -1;
        private Guid contextGuid = Guid.Empty; // 
        private int parentContextId = -1;
        private int completedOrderId = -1; 
        private PersistFlags flags = 0; 

        internal ActivityExecutionContextInfo(string qualifiedName, int contextId, Guid contextGuid, int parentContextId) 
        {
            this.qualifiedID = qualifiedName;
            this.contextId = contextId;
            this.contextGuid = contextGuid; 
            this.parentContextId = parentContextId;
        } 
 
        internal int ContextId
        { 
            get
            {
                return this.contextId;
            } 
        }
 
        public Guid ContextGuid 
        {
            get 
            {
                return this.contextGuid;
            }
        } 

        public string ActivityQualifiedName 
        { 
            get
            { 
                return this.qualifiedID;
            }
        }
 
        public int CompletedOrderId
        { 
            get 
            {
                return this.completedOrderId; 
            }
        }

        internal int ParentContextId 
        {
            get 
            { 
                return this.parentContextId;
            } 
        }

        internal void SetCompletedOrderId(int completedOrderId)
        { 
            this.completedOrderId = completedOrderId;
        } 
 
        internal PersistFlags Flags
        { 
            get
            {
                return this.flags;
            } 

            set 
            { 
                this.flags = value;
            } 
        }

        public override int GetHashCode()
        { 
            return contextGuid.GetHashCode();
        } 
 
        public override bool Equals(object obj)
        { 
            ActivityExecutionContextInfo otherContextInfo = obj as ActivityExecutionContextInfo;

            if (otherContextInfo != null)
            { 
                return this.ContextGuid.Equals(otherContextInfo.ContextGuid);
            } 
            return false; 
        }
    } 

    #endregion
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
                        

Link Menu

Network programming in C#, Network Programming in VB.NET, Network Programming in .NET
This book is available now!
Buy at Amazon US or
Buy at Amazon UK