Initial check-in of UA .NET source code

Author: Softing

ComIOP/Common/Client/Ae/AeAreaBrowser.cs

@@ -0,0 +1,285 @@
+/* ========================================================================
+ * Copyright (c) 2005-2013 The OPC Foundation, Inc. All rights reserved.
+ *
+ * OPC Foundation MIT License 1.00
+ * 
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ * 
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * The complete license agreement can be found here:
+ * http://opcfoundation.org/License/MIT/1.00/
+ * ======================================================================*/
+
+using System;
+using System.Collections.Generic;
+using System.Xml;
+using System.IO;
+using System.Reflection;
+using System.Threading;
+using Opc.Ua;
+using Opc.Ua.Server;
+using Opc.Ua.Com;
+using OpcRcw.Ae;
+using OpcRcw.Comn;
+
+namespace Opc.Ua.Com.Client
+{
+    /// <summary>
+    /// Browses the children of a segment.
+    /// </summary>
+    public class AeAreaBrower : NodeBrowser
+    {
+        #region Constructors
+        /// <summary>
+        /// Creates a new browser object with a set of filters.
+        /// </summary>
+        /// <param name="context">The system context to use.</param>
+        /// <param name="view">The view which may restrict the set of references/nodes found.</param>
+        /// <param name="referenceType">The type of references being followed.</param>
+        /// <param name="includeSubtypes">Whether subtypes of the reference type are followed.</param>
+        /// <param name="browseDirection">Which way the references are being followed.</param>
+        /// <param name="browseName">The browse name of a specific target (used when translating browse paths).</param>
+        /// <param name="additionalReferences">Any additional references that should be included.</param>
+        /// <param name="internalOnly">If true the browser should not making blocking calls to external systems.</param>
+        /// <param name="qualifiedName">Name of the qualified.</param>
+        /// <param name="namespaceIndex">Index of the namespace.</param>
+        public AeAreaBrower(
+            ISystemContext context,
+            ViewDescription view,
+            NodeId referenceType,
+            bool includeSubtypes,
+            BrowseDirection browseDirection,
+            QualifiedName browseName,
+            IEnumerable<IReference> additionalReferences,
+            bool internalOnly,
+            string qualifiedName,
+            ushort namespaceIndex)
+        :
+            base(
+                context,
+                view,
+                referenceType,
+                includeSubtypes,
+                browseDirection,
+                browseName,
+                additionalReferences,
+                internalOnly)
+        {
+            m_qualifiedName = qualifiedName;
+            m_namespaceIndex = namespaceIndex;
+            m_stage = Stage.Begin;
+        }
+        #endregion
+        
+        #region Overridden Methods
+        /// <summary>
+        /// Returns the next reference.
+        /// </summary>
+        /// <returns>The next reference that meets the browse criteria.</returns>
+        public override IReference Next()
+        {
+            lock (DataLock)
+            {
+                IReference reference = null;
+
+                // enumerate pre-defined references.
+                // always call first to ensure any pushed-back references are returned first.
+                reference = base.Next();
+
+                if (reference != null)
+                {
+                    return reference;
+                }
+
+                // don't start browsing huge number of references when only internal references are requested.
+                if (InternalOnly)
+                {
+                    return null;
+                }
+
+                // fetch references from the server.
+                do
+                {
+                    // fetch next reference.
+                    reference = NextChild();
+
+                    if (reference != null)
+                    {
+                        return reference;
+                    }
+
+                    // go to the next stage.
+                    NextStage();
+                }
+                while (m_stage != Stage.Done);
+
+                // all done.
+                return null;
+            }
+        }
+        #endregion
+
+        #region Private Methods
+        /// <summary>
+        /// Returns the next child.
+        /// </summary>
+        private IReference NextChild()
+        {
+            // check if a specific browse name is requested.
+            if (QualifiedName.IsNull(base.BrowseName))
+            {
+                return NextChild(m_stage);                
+            }
+
+            // keep fetching references until a matching browse name if found.
+            NodeStateReference reference = null;
+
+            do
+            {
+                reference = NextChild(m_stage);
+
+                if (reference != null)
+                {
+                    // need to let the caller look up the browse name.
+                    if (reference.Target == null)
+                    {
+                        return reference;
+                    }
+
+                    // check for browse name match.
+                    if (reference.Target.BrowseName == base.BrowseName)
+                    {
+                        return reference;
+                    }
+                }
+            }
+            while (reference != null);
+
+            // no match - need to go onto the next stage.
+            return null;
+        }
+
+        /// <summary>
+        /// Returns the next child.
+        /// </summary>
+        private NodeStateReference NextChild(Stage stage)
+        {
+            // fetch children.
+            if (stage == Stage.Children)
+            {
+                if (m_browser == null)
+                {
+                    return null;
+                }
+
+                BaseObjectState node = m_browser.Next(SystemContext, m_namespaceIndex);
+
+                if (node != null)
+                {
+                    return new NodeStateReference(ReferenceTypeIds.HasNotifier, false, node.NodeId);
+                }
+
+                // all done.
+                return null;
+            }
+
+            // fetch child parents.
+            if (stage == Stage.Parents)
+            {
+                return null;
+            }
+
+            return null;
+        }
+
+        /// <summary>
+        /// Initializes the next stage of browsing.
+        /// </summary>
+        private void NextStage()
+        {
+            ComAeClientManager system = (ComAeClientManager)this.SystemContext.SystemHandle;
+            ComAeClient client = system.SelectClient((ServerSystemContext)SystemContext, false);
+
+            // determine which stage is next based on the reference types requested.
+            for (Stage next = m_stage+1; next <= Stage.Done; next++)
+            {
+                if (next == Stage.Children)
+                {
+                    if (IsRequired(ReferenceTypeIds.HasNotifier, false))
+                    {
+                        m_stage = next;
+                        break;
+                    }
+                }
+
+                else if (next == Stage.Parents)
+                {
+                    if (IsRequired(ReferenceTypeIds.HasNotifier, true))
+                    {
+                        m_stage = next;
+                        break;
+                    }
+                }
+
+                else if (next == Stage.Done)
+                {
+                    m_stage = next;
+                    break;
+                }
+            }
+
+            // start enumerating areas.
+            if (m_stage == Stage.Children)
+            {
+                m_browser = new ComAeBrowserClient(client, m_qualifiedName);
+                return;
+            }
+
+            // start enumerating parents.
+            if (m_stage == Stage.Parents)
+            {
+                return;
+            }
+
+            // all done.
+        }
+        #endregion
+
+        #region Stage Enumeration
+        /// <summary>
+        /// The stages available in a browse operation.
+        /// </summary>
+        private enum Stage
+        {
+            Begin,
+            Children,
+            Parents,
+            Done
+        }
+        #endregion
+
+        #region Private Fields
+        private Stage m_stage;
+        private string m_qualifiedName;
+        private ushort m_namespaceIndex;
+        private ComAeBrowserClient m_browser;
+        #endregion
+    }
+}