SignatureGenerator.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / Dotnetfx_Vista_SP2 / Dotnetfx_Vista_SP2 / 8.0.50727.4016 / DEVDIV / depot / DevDiv / releases / Orcas / QFE / ndp / fx / src / DataEntity / System / Data / Map / ViewGeneration / SignatureGenerator.cs / 2 / SignatureGenerator.cs
                        

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

using System.Data.Common; 
using System.Data.Common.Utils;
using System.Data.Mapping.ViewGeneration.Structures;
using System.Collections.Generic;
using System.Text; 
using System.Diagnostics;
using System.Data.Metadata.Edm; 
 
namespace System.Data.Mapping.ViewGeneration {
 
    using AttributeSet = Set;

    // This class is responsible for managing  various multi-constants that
    // are used in the cell normalization process. It handles their 
    // generation and usage along with the generating of the attributes that
    // are needed with each multiconstant, i.e., it generates a signature for 
    // each multiconstant 
    internal class SignatureGenerator : InternalBase {
 
        #region Constructor

        // effects: Given an extent and the different condition members
        // (e.g., isHighpriority, discriminator) that are used in the cells 
        // for this extent, creates a SignatureGenerator object that is
        // capable of giving the signatures for the cells 
        internal SignatureGenerator(EntitySetBase extent, MetadataWorkspace workspace) { 

            m_workspace = workspace; 

            // We generate the indices for the projected slots as we traverse the metadata
            m_projectedSlotMap = new MemberPathMap();
 
            // Determine the different values that various types inside
            // Extent can take can take and compute their cross product to 
            // obtain the set of multiconstants for this extent, 
            // e.g. Person-Address, Customer-Address-Phone (if only customers
            // have phones) 
            MemberPath extentMember  = new MemberPath(extent, workspace);
                GatherPartialSignature(extentMember,
                                       false, // not nullable
                                       false); // need not only keys 
        }
        #endregion 
 

        #region Fields 
        // Tracks mapping of members of the left side to their corresponding
        // projected slots (for the aligned right query in a cell wrapper,
        // the fields are stored in the order specified by this map)
        private MemberPathMap m_projectedSlotMap; 

        private MetadataWorkspace m_workspace; 
        #endregion 

 
        #region Properties
        // effects: Returns a map that maps member paths of the extent (for
        // which a view is being generated) to a dense space of numbers from
        // 0 such that each member's number is larger than it's parent's 
        // number, e.g., if Person.Address.Zip has 5 then Person.Address is
        // less than 5. Say if it is 3 then Person is less than 3. 
        internal MemberPathMapBase ProjectedSlotMap { 
            get { return m_projectedSlotMap; }
        } 
        #endregion

        #region Methods
        // requires: member is an Entity or Complex or Relation type 
        // effects: Starting at "member", generates the multiconstant signatures for
        // all the fields embedded in it. isNullable indicates if member can 
        // be nulled or not. needKeysOnly indicates whether we need to only 
        // collect members that are keys.
        private void 
        GatherPartialSignature(MemberPath member, bool isNullable, bool needKeysOnly) {

            EdmType memberType = member.EdmType;
            ComplexType complexTypemember = memberType as ComplexType; 
            Debug.Assert(complexTypemember !=null ||
                         memberType is EntityType || // for entity sets 
                         memberType is AssociationType || // For relation sets 
                         memberType is RefType, // for relation ends
                         "GatherPartialSignature only for complex types, entity sets, relationship ends"); 

            if (memberType is ComplexType && needKeysOnly) {
                // CHANGE_[....]_FEATURE_COMPLEX_TYPE_KEYS
                // Check if the complex type needs to be traversed or not. If not, just return 
                // from here. Else we need to continue to the code below. Right now, we do not
                // allow keys inside complex types 
                return; 
            }
 
            // Make sure that this member is in the slot map before any of
            // its embedded objects
            m_projectedSlotMap.CreateIndex(member);
 
            // Add the types can member have, i.e., its type and its subtypes
            List possibleTypes = new List(); 
            possibleTypes.AddRange(MetadataHelper.GetTypeAndSubtypesOf(memberType, m_workspace, false /*includeAbstractTypes*/)); 

            // Consider each possible type value -- each type value 
            // conributes to a tuple in the result. For that possible type,
            // add all the type members into the signature
            foreach (EdmType possibleType in possibleTypes) {
 
                // first, collect all scalar-typed members of this type in a signature
                    GatherSignatureFromScalars(member, possibleType, needKeysOnly); 
 
                // Now drill down into complex-valued members and get a cross
                // product of the existing signatures 
                // CHANGE_[....]_FEATURE_COMPLEX_KEYS: Need to handle getting key fields from complex types
                    GatherSignaturesFromNonScalars(member, possibleType, needKeysOnly);
            }
        } 

        // requires: possibleType is the member's type or one of its subtypes 
        // possibleType is a StructuralType 
        // effects: Given a member and the corresponding possible type
        // that it can take, determine the attributes that are relevant 
        // for this possibleType and returns a multiconstant signature
        // corresponding to this possibleType and the attributes. If only
        // keys are needed, collect the key fields only. memberSlotId
        // indicates the slot number allocated for member in the multiconstant 
        private void GatherSignatureFromScalars(MemberPath member,
                                                                  EdmType possibleType, 
                                                                  bool needKeysOnly) { 

            // For each child member of this type, collect all the relevant scalar fields 
            StructuralType structuralType = (StructuralType) possibleType;;
            foreach (EdmMember childMetadata in structuralType.Members) {
                if (!Helper.IsEdmProperty(childMetadata)) {
                    // We only care about properties. Associations Ends are 
                    // captured in NonScalars really
                    continue; 
                } 
                EdmProperty childProperty = (EdmProperty)childMetadata;
 
                // Collect all scalar-typed members of this type
                // if needKeysOnly, collect only keys

                if (MetadataHelper.IsNonRefSimpleMember(childProperty) && 
                    (!needKeysOnly || MetadataHelper.IsPartOfEntityTypeKey(childProperty))) {
                    MemberPath scalarMember = new MemberPath(member, childMetadata); 
                    // Note: scalarMember's parent has already been added to the projectedSlotMap 
                    m_projectedSlotMap.CreateIndex(scalarMember);
                } 
            }
        }

        // requires: possibleType is the member's type or one of its subtypes 
        // effects: Given a member and the corresponding possible type that
        // it can be, computes a cross-product of initial signature with the 
        // different types that can occur inside possibleType 
        private void
        GatherSignaturesFromNonScalars(MemberPath member, EdmType possibleType, 
                                       bool needKeysOnly) {

            int childNumber = 0;
 
            // Go through all the members for the complex type while ignoring scalars
            foreach (EdmMember childMember in Helper.GetAllStructuralMembers(possibleType)) 
            { 
                childNumber++;
                if (MetadataHelper.IsNonRefSimpleMember(childMember)) { 
                    continue;
                }
                // CHANGE_[....]_FEATURE_COMPOSITION Fix as composition changes in metadata
                Debug.Assert(childMember.TypeUsage.EdmType is ComplexType || 
                             childMember.TypeUsage.EdmType is RefType, // for relation ends
                             "Only non-scalars currently handled -- complex types, relationship ends"); 
 
                // RefTypes are not nullable
                bool isNullable = MetadataHelper.IsMemberNullable(childMember); 
                // Only keys are required for entities hanging off relation ends of an association
                // or for the first end of composition
                needKeysOnly = needKeysOnly || (childMember is AssociationEndMember);
                // CHANGE_[....]_FEATURE_COMPOSITION 
                // (childNumber == 0 || false == ((RelationType)possibleType).IsComposition);
                MemberPath nonScalarMember = new MemberPath(member, childMember); 
                    GatherPartialSignature(nonScalarMember, isNullable, needKeysOnly); 

            } 
        }

        #endregion
 
        #region String methods
        internal override void ToCompactString(StringBuilder builder) { 
            builder.Append("Projected Slot Map: "); 
            m_projectedSlotMap.ToCompactString(builder);
        } 
        #endregion
    }
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//---------------------------------------------------------------------- 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// 
// @owner [....]
// @backupOwner [....] 
//--------------------------------------------------------------------- 

using System.Data.Common; 
using System.Data.Common.Utils;
using System.Data.Mapping.ViewGeneration.Structures;
using System.Collections.Generic;
using System.Text; 
using System.Diagnostics;
using System.Data.Metadata.Edm; 
 
namespace System.Data.Mapping.ViewGeneration {
 
    using AttributeSet = Set;

    // This class is responsible for managing  various multi-constants that
    // are used in the cell normalization process. It handles their 
    // generation and usage along with the generating of the attributes that
    // are needed with each multiconstant, i.e., it generates a signature for 
    // each multiconstant 
    internal class SignatureGenerator : InternalBase {
 
        #region Constructor

        // effects: Given an extent and the different condition members
        // (e.g., isHighpriority, discriminator) that are used in the cells 
        // for this extent, creates a SignatureGenerator object that is
        // capable of giving the signatures for the cells 
        internal SignatureGenerator(EntitySetBase extent, MetadataWorkspace workspace) { 

            m_workspace = workspace; 

            // We generate the indices for the projected slots as we traverse the metadata
            m_projectedSlotMap = new MemberPathMap();
 
            // Determine the different values that various types inside
            // Extent can take can take and compute their cross product to 
            // obtain the set of multiconstants for this extent, 
            // e.g. Person-Address, Customer-Address-Phone (if only customers
            // have phones) 
            MemberPath extentMember  = new MemberPath(extent, workspace);
                GatherPartialSignature(extentMember,
                                       false, // not nullable
                                       false); // need not only keys 
        }
        #endregion 
 

        #region Fields 
        // Tracks mapping of members of the left side to their corresponding
        // projected slots (for the aligned right query in a cell wrapper,
        // the fields are stored in the order specified by this map)
        private MemberPathMap m_projectedSlotMap; 

        private MetadataWorkspace m_workspace; 
        #endregion 

 
        #region Properties
        // effects: Returns a map that maps member paths of the extent (for
        // which a view is being generated) to a dense space of numbers from
        // 0 such that each member's number is larger than it's parent's 
        // number, e.g., if Person.Address.Zip has 5 then Person.Address is
        // less than 5. Say if it is 3 then Person is less than 3. 
        internal MemberPathMapBase ProjectedSlotMap { 
            get { return m_projectedSlotMap; }
        } 
        #endregion

        #region Methods
        // requires: member is an Entity or Complex or Relation type 
        // effects: Starting at "member", generates the multiconstant signatures for
        // all the fields embedded in it. isNullable indicates if member can 
        // be nulled or not. needKeysOnly indicates whether we need to only 
        // collect members that are keys.
        private void 
        GatherPartialSignature(MemberPath member, bool isNullable, bool needKeysOnly) {

            EdmType memberType = member.EdmType;
            ComplexType complexTypemember = memberType as ComplexType; 
            Debug.Assert(complexTypemember !=null ||
                         memberType is EntityType || // for entity sets 
                         memberType is AssociationType || // For relation sets 
                         memberType is RefType, // for relation ends
                         "GatherPartialSignature only for complex types, entity sets, relationship ends"); 

            if (memberType is ComplexType && needKeysOnly) {
                // CHANGE_[....]_FEATURE_COMPLEX_TYPE_KEYS
                // Check if the complex type needs to be traversed or not. If not, just return 
                // from here. Else we need to continue to the code below. Right now, we do not
                // allow keys inside complex types 
                return; 
            }
 
            // Make sure that this member is in the slot map before any of
            // its embedded objects
            m_projectedSlotMap.CreateIndex(member);
 
            // Add the types can member have, i.e., its type and its subtypes
            List possibleTypes = new List(); 
            possibleTypes.AddRange(MetadataHelper.GetTypeAndSubtypesOf(memberType, m_workspace, false /*includeAbstractTypes*/)); 

            // Consider each possible type value -- each type value 
            // conributes to a tuple in the result. For that possible type,
            // add all the type members into the signature
            foreach (EdmType possibleType in possibleTypes) {
 
                // first, collect all scalar-typed members of this type in a signature
                    GatherSignatureFromScalars(member, possibleType, needKeysOnly); 
 
                // Now drill down into complex-valued members and get a cross
                // product of the existing signatures 
                // CHANGE_[....]_FEATURE_COMPLEX_KEYS: Need to handle getting key fields from complex types
                    GatherSignaturesFromNonScalars(member, possibleType, needKeysOnly);
            }
        } 

        // requires: possibleType is the member's type or one of its subtypes 
        // possibleType is a StructuralType 
        // effects: Given a member and the corresponding possible type
        // that it can take, determine the attributes that are relevant 
        // for this possibleType and returns a multiconstant signature
        // corresponding to this possibleType and the attributes. If only
        // keys are needed, collect the key fields only. memberSlotId
        // indicates the slot number allocated for member in the multiconstant 
        private void GatherSignatureFromScalars(MemberPath member,
                                                                  EdmType possibleType, 
                                                                  bool needKeysOnly) { 

            // For each child member of this type, collect all the relevant scalar fields 
            StructuralType structuralType = (StructuralType) possibleType;;
            foreach (EdmMember childMetadata in structuralType.Members) {
                if (!Helper.IsEdmProperty(childMetadata)) {
                    // We only care about properties. Associations Ends are 
                    // captured in NonScalars really
                    continue; 
                } 
                EdmProperty childProperty = (EdmProperty)childMetadata;
 
                // Collect all scalar-typed members of this type
                // if needKeysOnly, collect only keys

                if (MetadataHelper.IsNonRefSimpleMember(childProperty) && 
                    (!needKeysOnly || MetadataHelper.IsPartOfEntityTypeKey(childProperty))) {
                    MemberPath scalarMember = new MemberPath(member, childMetadata); 
                    // Note: scalarMember's parent has already been added to the projectedSlotMap 
                    m_projectedSlotMap.CreateIndex(scalarMember);
                } 
            }
        }

        // requires: possibleType is the member's type or one of its subtypes 
        // effects: Given a member and the corresponding possible type that
        // it can be, computes a cross-product of initial signature with the 
        // different types that can occur inside possibleType 
        private void
        GatherSignaturesFromNonScalars(MemberPath member, EdmType possibleType, 
                                       bool needKeysOnly) {

            int childNumber = 0;
 
            // Go through all the members for the complex type while ignoring scalars
            foreach (EdmMember childMember in Helper.GetAllStructuralMembers(possibleType)) 
            { 
                childNumber++;
                if (MetadataHelper.IsNonRefSimpleMember(childMember)) { 
                    continue;
                }
                // CHANGE_[....]_FEATURE_COMPOSITION Fix as composition changes in metadata
                Debug.Assert(childMember.TypeUsage.EdmType is ComplexType || 
                             childMember.TypeUsage.EdmType is RefType, // for relation ends
                             "Only non-scalars currently handled -- complex types, relationship ends"); 
 
                // RefTypes are not nullable
                bool isNullable = MetadataHelper.IsMemberNullable(childMember); 
                // Only keys are required for entities hanging off relation ends of an association
                // or for the first end of composition
                needKeysOnly = needKeysOnly || (childMember is AssociationEndMember);
                // CHANGE_[....]_FEATURE_COMPOSITION 
                // (childNumber == 0 || false == ((RelationType)possibleType).IsComposition);
                MemberPath nonScalarMember = new MemberPath(member, childMember); 
                    GatherPartialSignature(nonScalarMember, isNullable, needKeysOnly); 

            } 
        }

        #endregion
 
        #region String methods
        internal override void ToCompactString(StringBuilder builder) { 
            builder.Append("Projected Slot Map: "); 
            m_projectedSlotMap.ToCompactString(builder);
        } 
        #endregion
    }
}

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

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