complextypematerializer.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 / fx / src / DataEntity / System / Data / Objects / Internal / complextypematerializer.cs / 1305376 / complextypematerializer.cs
                        

                        
                            //---------------------------------------------------------------------- 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// 
// @owner       [....]
// @backupOwner [....] 
//--------------------------------------------------------------------- 

using System.Data.Metadata.Edm; 
using System.Data.Common;
using System.Diagnostics;
using System.Data.Mapping;
namespace System.Data.Objects.Internal 
{
    ///  
    /// Supports materialization of complex type instances from records. Used 
    /// by the ObjectStateManager.
    ///  
    internal class ComplexTypeMaterializer
    {
        private readonly MetadataWorkspace _workspace;
        private const int MaxPlanCount = 4; 
        private Plan[] _lastPlans;
        private int _lastPlanIndex; 
 
        internal ComplexTypeMaterializer(MetadataWorkspace workspace)
        { 
            _workspace = workspace;
        }

        internal object CreateComplex(IExtendedDataRecord record, DataRecordInfo recordInfo, object result) 
        {
            Debug.Assert(null != record, "null IExtendedDataRecord"); 
            Debug.Assert(null != recordInfo, "null DataRecordInfo"); 
            Debug.Assert(null != recordInfo.RecordType, "null TypeUsage");
            Debug.Assert(null != recordInfo.RecordType.EdmType, "null EdmType"); 

            Debug.Assert(Helper.IsEntityType(recordInfo.RecordType.EdmType) ||
                         Helper.IsComplexType(recordInfo.RecordType.EdmType),
                         "not EntityType or ComplexType"); 

            Plan plan = GetPlan(record, recordInfo); 
            if (null == result) 
            {
                result = ((Func)plan.ClrType)(); 
            }
            SetProperties(record, result, plan.Properties);
            return result;
        } 

        private void SetProperties(IExtendedDataRecord record, object result, PlanEdmProperty[] properties) 
        { 
            Debug.Assert(null != record, "null IExtendedDataRecord");
            Debug.Assert(null != result, "null object"); 
            Debug.Assert(null != properties, "null object");

            for (int i = 0; i < properties.Length; ++i)
            { 
                if (null != properties[i].GetExistingComplex)
                { 
                    object existing = properties[i].GetExistingComplex(result); 
                    object obj = CreateComplexRecursive(record.GetValue(properties[i].Ordinal), existing);
                    if (null == existing) 
                    {
                        properties[i].ClrProperty(result, obj);
                    }
                } 
                else
                { 
                    properties[i].ClrProperty(result, 
                        ConvertDBNull(
                            record.GetValue( 
                                properties[i].Ordinal)));
                }
            }
        } 

        private static object ConvertDBNull(object value) 
        { 
            return ((DBNull.Value != value) ? value : null);
        } 

        private object CreateComplexRecursive(object record, object existing)
        {
            return ((DBNull.Value != record) ? CreateComplexRecursive((IExtendedDataRecord)record, existing) : existing); 
        }
 
        private object CreateComplexRecursive(IExtendedDataRecord record, object existing) 
        {
            return CreateComplex(record, record.DataRecordInfo, existing); 
        }

        private Plan GetPlan(IExtendedDataRecord record, DataRecordInfo recordInfo)
        { 
            Debug.Assert(null != record, "null IExtendedDataRecord");
            Debug.Assert(null != recordInfo, "null DataRecordInfo"); 
            Debug.Assert(null != recordInfo.RecordType, "null TypeUsage"); 

            Plan[] plans = _lastPlans ?? (_lastPlans = new Plan[MaxPlanCount]); 

            // find an existing plan in circular buffer
            int index = _lastPlanIndex - 1;
            for (int i = 0; i < MaxPlanCount; ++i) 
            {
                index = (index + 1) % MaxPlanCount; 
                if (null == plans[index]) 
                {
                    break; 
                }
                if (plans[index].Key == recordInfo.RecordType)
                {
                    _lastPlanIndex = index; 
                    return plans[index];
                } 
            } 
            Debug.Assert(0 <= index, "negative index");
            Debug.Assert(index != _lastPlanIndex || (null == plans[index]), "index wrapped around"); 

            // create a new plan
            ObjectTypeMapping mapping = System.Data.Common.Internal.Materialization.Util.GetObjectMapping(recordInfo.RecordType.EdmType, _workspace);
            Debug.Assert(null != mapping, "null ObjectTypeMapping"); 

            Debug.Assert(Helper.IsComplexType(recordInfo.RecordType.EdmType), 
                         "IExtendedDataRecord is not ComplexType"); 

            _lastPlanIndex = index; 
            plans[index] = new Plan(recordInfo.RecordType, mapping, recordInfo.FieldMetadata);
            return plans[index];
        }
 
        private sealed class Plan
        { 
            internal readonly TypeUsage Key; 
            internal readonly Delegate ClrType;
            internal readonly PlanEdmProperty[] Properties; 

            internal Plan(TypeUsage key, ObjectTypeMapping mapping, System.Collections.ObjectModel.ReadOnlyCollection fields)
            {
                Debug.Assert(null != mapping, "null ObjectTypeMapping"); 
                Debug.Assert(null != fields, "null FieldMetadata");
 
                Key = key; 
                Debug.Assert(!Helper.IsEntityType(mapping.ClrType), "Expecting complex type");
                ClrType = LightweightCodeGenerator.GetConstructorDelegateForType((ClrComplexType)mapping.ClrType); 
                Properties = new PlanEdmProperty[fields.Count];

                int lastOrdinal = -1;
                for (int i = 0; i < Properties.Length; ++i) 
                {
                    FieldMetadata field = fields[i]; 
 
                    Debug.Assert(unchecked((uint)field.Ordinal) < unchecked((uint)fields.Count), "FieldMetadata.Ordinal out of range of Fields.Count");
                    Debug.Assert(lastOrdinal < field.Ordinal, "FieldMetadata.Ordinal is not increasing"); 
                    lastOrdinal = field.Ordinal;

                    Properties[i] = new PlanEdmProperty(lastOrdinal, mapping.GetPropertyMap(field.FieldType.Name).ClrProperty);
                } 
            }
        } 
 
        private struct PlanEdmProperty
        { 
            internal readonly int Ordinal;
            internal readonly Func GetExistingComplex;
            internal readonly Action ClrProperty;
 
            internal PlanEdmProperty(int ordinal, EdmProperty property)
            { 
                Debug.Assert(0 <= ordinal, "negative ordinal"); 
                Debug.Assert(null != property, "unsupported shadow state");
 
                this.Ordinal = ordinal;
                this.GetExistingComplex = Helper.IsComplexType(property.TypeUsage.EdmType)
                    ? LightweightCodeGenerator.GetGetterDelegateForProperty(property) : null;
                this.ClrProperty = LightweightCodeGenerator.GetSetterDelegateForProperty(property); 
            }
        } 
    } 
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.


                        

                        

                        
                        
                    
                    

                        
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