StateMachineSubscription.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / cdf / src / WF / Activities / StateMachineSubscription.cs / 1305376 / StateMachineSubscription.cs
                        

                        
                            #region Using directives 

using System;
using System.Collections;
using System.Collections.Generic; 
using System.Collections.Specialized;
using System.Reflection; 
using System.Diagnostics; 
using System.Runtime.Remoting.Messaging;
using System.Workflow.ComponentModel; 
using System.Workflow.ComponentModel.Design;
using System.Workflow.Runtime;
using System.Workflow.Runtime.Hosting;
 
#endregion Using directives
 
namespace System.Workflow.Activities 
{
    #region StateMachineSubscription 

    [Serializable]
    internal abstract class StateMachineSubscription : IActivityEventListener
    { 
        #region Member Variables
 
        private Guid _subscriptionId; 

        #endregion Member Variables 

        #region Properties

        internal Guid SubscriptionId 
        {
            get 
            { 
                return _subscriptionId;
            } 
            set
            {
                _subscriptionId = value;
            } 
        }
 
        #endregion Properties 

        void IActivityEventListener.OnEvent(object sender, QueueEventArgs e) 
        {
            ActivityExecutionContext context = sender as ActivityExecutionContext;
            if (context == null)
                throw new ArgumentException(SR.Error_SenderMustBeActivityExecutionContext, "sender"); 

            Enqueue(context); 
        } 

        protected abstract void Enqueue(ActivityExecutionContext context); 
        internal abstract void ProcessEvent(ActivityExecutionContext context);
    }

    #endregion StateMachineSubscription 

    #region EventActivitySubscription 
 
    [Serializable]
    internal class EventActivitySubscription : StateMachineSubscription 
    {
        #region Member Variables

        private string _eventActivityName = String.Empty; 
        private string _eventDrivenName = String.Empty;
        private string _stateName = String.Empty; 
        private IComparable _queueName; 

        #endregion Member Variables 

        #region Properties

        internal string EventActivityName 
        {
            get 
            { 
                return _eventActivityName;
            } 
        }

        internal string StateName
        { 
            get
            { 
                return _stateName; 
            }
        } 

        internal IComparable QueueName
        {
            get 
            {
                return _queueName; 
            } 
        }
 
        internal string EventDrivenName
        {
            get
            { 
                return _eventDrivenName;
            } 
        } 

        #endregion Properties 

        internal void Subscribe(ActivityExecutionContext context,
            StateActivity state,
            IEventActivity eventActivity) 
        {
            eventActivity.Subscribe(context, this); 
            Activity activity = (Activity)eventActivity; 
            this._queueName = eventActivity.QueueName;
            this._eventActivityName = activity.QualifiedName; 
            this._stateName = state.QualifiedName;
            this.SubscriptionId = Guid.NewGuid();
            EventDrivenActivity eventDriven = StateMachineHelpers.GetParentEventDriven(eventActivity);
            this._eventDrivenName = eventDriven.QualifiedName; 
        }
 
        internal void Unsubscribe(ActivityExecutionContext context, 
            IEventActivity eventActivity)
        { 
            eventActivity.Unsubscribe(context, this);
        }

        protected override void Enqueue(ActivityExecutionContext context) 
        {
            StateActivity rootState = StateMachineHelpers.GetRootState((StateActivity)context.Activity); 
            StateMachineExecutionState executionState = StateMachineExecutionState.Get(rootState); 
            executionState.SubscriptionManager.Enqueue(context, this.QueueName);
        } 

        internal override void ProcessEvent(ActivityExecutionContext context)
        {
            StateActivity rootState = StateMachineHelpers.GetRootState((StateActivity)context.Activity); 
            StateMachineExecutionState executionState = StateMachineExecutionState.Get(rootState);
            ExternalEventAction action = new ExternalEventAction(this.StateName, this.EventDrivenName); 
            Debug.Assert(!executionState.HasEnqueuedActions); 
            executionState.EnqueueAction(action);
            executionState.ProcessActions(context); 
        }
    }

    #endregion EventActivitySubscription 

    #region SetStateSubscription 
 
    [Serializable]
    internal class SetStateSubscription : StateMachineSubscription 
    {
        private Guid _instanceId;

        internal SetStateSubscription(Guid instanceId) 
        {
            this._instanceId = instanceId; 
        } 

        internal void CreateQueue(ActivityExecutionContext context) 
        {
            if (!StateMachineHelpers.IsRootExecutionContext(context))
            {
                // we only subscribe to the set state event if 
                // we're at the root level. If this instance is
                // being called, it is not possible to set the 
                // state from the host side directly 
                return;
            } 

            WorkflowQueuingService workflowQueuingService = context.GetService();

            MessageEventSubscription subscription = new MessageEventSubscription( 
                StateMachineWorkflowActivity.SetStateQueueName,
                this._instanceId); 
 
            WorkflowQueue workflowQueue = workflowQueuingService.CreateWorkflowQueue(
                StateMachineWorkflowActivity.SetStateQueueName, 
                true);
            this.SubscriptionId = subscription.SubscriptionId;
        }
 
        internal void DeleteQueue(ActivityExecutionContext context)
        { 
            if (!StateMachineHelpers.IsRootExecutionContext(context)) 
            {
                // we only subscribe to the set state event if 
                // we're at the root level. If this instance is
                // being called, it is not possible to set the
                // state from the host side directly
                return; 
            }
 
            WorkflowQueuingService workflowQueuingService = context.GetService(); 
            WorkflowQueue workflowQueue = workflowQueuingService.GetWorkflowQueue(StateMachineWorkflowActivity.SetStateQueueName);
            workflowQueuingService.DeleteWorkflowQueue(StateMachineWorkflowActivity.SetStateQueueName); 
        }

        internal void Subscribe(ActivityExecutionContext context)
        { 
            WorkflowQueuingService workflowQueuingService = context.GetService();
            WorkflowQueue workflowQueue = workflowQueuingService.GetWorkflowQueue(StateMachineWorkflowActivity.SetStateQueueName); 
            workflowQueue.RegisterForQueueItemAvailable(this); 
        }
 
        internal void Unsubscribe(ActivityExecutionContext context)
        {
            WorkflowQueuingService workflowQueuingService = context.GetService();
            WorkflowQueue workflowQueue = workflowQueuingService.GetWorkflowQueue(StateMachineWorkflowActivity.SetStateQueueName); 
            workflowQueue.UnregisterForQueueItemAvailable(this);
        } 
 
        protected override void Enqueue(ActivityExecutionContext context)
        { 
            StateActivity rootState = StateMachineHelpers.GetRootState((StateActivity)context.Activity);
            StateMachineExecutionState executionState = StateMachineExecutionState.Get(rootState);
            executionState.SubscriptionManager.Enqueue(context, this.SubscriptionId);
        } 

        internal override void ProcessEvent(ActivityExecutionContext context) 
        { 
            WorkflowQueuingService workflowQueuingService = context.GetService();
            WorkflowQueue workflowQueue = workflowQueuingService.GetWorkflowQueue(StateMachineWorkflowActivity.SetStateQueueName); 
            SetStateEventArgs eventArgs = workflowQueue.Dequeue() as SetStateEventArgs;
            StateActivity currentState = StateMachineHelpers.GetCurrentState(context);
            if (currentState == null)
                throw new InvalidOperationException(SR.GetStateMachineWorkflowMustHaveACurrentState()); 

            StateActivity rootState = StateMachineHelpers.GetRootState((StateActivity)context.Activity); 
            StateMachineExecutionState executionState = StateMachineExecutionState.Get(rootState); 
            SetStateAction action = new SetStateAction(currentState.QualifiedName, eventArgs.TargetStateName);
            Debug.Assert(!executionState.HasEnqueuedActions); 
            executionState.EnqueueAction(action);
            executionState.ProcessActions(context);
        }
    } 

    #endregion SetStateSubscription 
} 

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

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