mcs/class/referencesource/System.Data.Linq/Mapping/MetaModel.cs

   1 using System;
   2 using System.Collections;
   3 using System.Collections.Generic;
   4 using System.Collections.ObjectModel;
   5 using System.Data.Linq;
   6 using System.Linq.Expressions;
   7 using System.Reflection;
   8 using System.Text;
   9 using System.Linq;
  10 using System.Diagnostics.CodeAnalysis;
  11
  12 namespace System.Data.Linq.Mapping {
  13     /// <summary>
  14     /// A MetaModel is an abstraction representing the mapping between a database and domain objects
  15     /// </summary>
  16     public abstract class MetaModel {
  17         /// <summary>
  18         ///  The mapping source that originated this model.
  19         /// </summary>
  20         public abstract MappingSource MappingSource { get; }
  21         /// <summary>
  22         /// The type of DataContext type this model describes.
  23         /// </summary>
  24         public abstract Type ContextType { get; }
  25         /// <summary>
  26         /// The name of the database.
  27         /// </summary>
  28         public abstract string DatabaseName { get; }
  29         /// <summary>
  30         /// The CLR type that implements IProvider to use as a provider.
  31         /// </summary>
  32         public abstract Type ProviderType { get; }
  33         /// <summary>
  34         /// Gets the MetaTable associated with a given type.
  35         /// </summary>
  36         /// <param name="rowType">The CLR row type.</param>
  37         /// <returns>The MetaTable if one exists, otherwise null.</returns>
  38         public abstract MetaTable GetTable(Type rowType);
  39         /// <summary>
  40         /// Gets the MetaFunction corresponding to a database function: user-defined function, table-valued function or stored-procedure.
  41         /// </summary>
  42         /// <param name="method">The method defined on the DataContext or subordinate class that represents the database function.</param>
  43         /// <returns>The MetaFunction if one exists, otherwise null.</returns>
  44         public abstract MetaFunction GetFunction(MethodInfo method);
  45         /// <summary>
  46         /// Get an enumeration of all tables.
  47         /// </summary>
  48         /// <returns>An enumeration of all the MetaTables</returns>
  49         [SuppressMessage("Microsoft.Design", "CA1024:UsePropertiesWhereAppropriate", Justification="Non-trivial operations are not suitable for properties.")]
  50         public abstract IEnumerable<MetaTable> GetTables();
  51         /// <summary>
  52         /// Get an enumeration of all functions.
  53         /// </summary>
  54         /// <returns>An enumeration of all the MetaFunctions</returns>
  55         [SuppressMessage("Microsoft.Design", "CA1024:UsePropertiesWhereAppropriate", Justification="Non-trivial operations are not suitable for properties.")]
  56         public abstract IEnumerable<MetaFunction> GetFunctions();
  57         /// <summary>
  58         /// This method discovers the MetaType for the given Type.
  59         /// </summary>
  60         public abstract MetaType GetMetaType(Type type);
  61         /// <summary>
  62         /// Internal value used to determine a reference identity for comparing meta models
  63         /// without needing to keep track of the actual meta model reference.
  64         /// </summary>
  65         private object identity = new object();
  66         internal object Identity {
  67             get { return this.identity; }
  68         }
  69     }
  70
  71     /// <summary>
  72     /// A MetaTable represents an abstraction of a database table (or view)
  73     /// </summary>
  74     public abstract class MetaTable {
  75         /// <summary>
  76         /// The MetaModel containing this MetaTable.
  77         /// </summary>
  78         public abstract MetaModel Model { get; }
  79         /// <summary>
  80         /// The name of the table as defined by the database.
  81         /// </summary>
  82         public abstract string TableName { get; }
  83         /// <summary>
  84         /// The MetaType describing the type of the rows of the table.
  85         /// </summary>
  86         public abstract MetaType RowType { get; }
  87         /// <summary>
  88         /// The DataContext method used to perform insert operations
  89         /// </summary>
  90         public abstract MethodInfo InsertMethod { get; }
  91         /// <summary>
  92         /// The DataContext method used to perform update operations
  93         /// </summary>
  94         public abstract MethodInfo UpdateMethod { get; }
  95         /// <summary>
  96         /// The DataContext method used to perform delete operations
  97         /// </summary>
  98         public abstract MethodInfo DeleteMethod { get; }
  99     }
 100
 101     /// <summary>
 102     /// A MetaType represents the mapping of a domain object type onto a database table's columns.
 103     /// </summary>
 104     public abstract class MetaType {
 105         /// <summary>
 106         /// The MetaModel containing this MetaType.
 107         /// </summary>
 108         public abstract MetaModel Model { get; }
 109         /// <summary>
 110         /// The MetaTable using this MetaType for row definition.
 111         /// </summary>
 112         public abstract MetaTable Table { get; }
 113         /// <summary>
 114         /// The underlying CLR type.
 115         /// </summary>
 116         [SuppressMessage("Microsoft.Naming", "CA1721:PropertyNamesShouldNotMatchGetMethods", Justification = "The contexts in which this is available are fairly specific.")]
 117         public abstract Type Type { get; }
 118         /// <summary>
 119         /// The name of the MetaType (same as the CLR type's name).
 120         /// </summary>
 121         public abstract string Name { get; }
 122         /// <summary>
 123         /// True if the MetaType is an entity type.
 124         /// </summary>
 125         public abstract bool IsEntity { get; }
 126         /// <summary>
 127         /// True if the underlying type can be instantiated as the result of a query.
 128         /// </summary>
 129         public abstract bool CanInstantiate { get; }
 130         /// <summary>
 131         /// The member that represents the auto-generated identity column, or null if there is none.
 132         /// </summary>
 133         public abstract MetaDataMember DBGeneratedIdentityMember { get; }
 134         /// <summary>
 135         /// The member that represents the row-version or timestamp column, or null if there is none.
 136         /// </summary>
 137         public abstract MetaDataMember VersionMember { get; }
 138         /// <summary>
 139         /// The member that represents the inheritance discriminator column, or null if there is none.
 140         /// </summary>
 141         public abstract MetaDataMember Discriminator { get; }
 142         /// <summary>
 143         /// True if the type has any persistent member with an UpdateCheck policy other than Never.
 144         /// </summary>
 145         public abstract bool HasUpdateCheck { get; }
 146         /// <summary>
 147         /// True if the type is part of a mapped inheritance hierarchy.
 148         /// </summary>
 149         public abstract bool HasInheritance { get; }
 150         /// <summary>
 151         /// True if this type defines an inheritance code.
 152         /// </summary>
 153         public abstract bool HasInheritanceCode { get; }
 154         /// <summary>
 155         /// The inheritance code defined by this type.
 156         /// </summary>
 157         public abstract object InheritanceCode { get; }
 158         /// <summary>
 159         /// True if this type is used as the default of an inheritance hierarchy.
 160         /// </summary>
 161         public abstract bool IsInheritanceDefault { get; }
 162         /// <summary>
 163         /// The root type of the inheritance hierarchy.
 164         /// </summary>
 165         public abstract MetaType InheritanceRoot { get; }
 166         /// <summary>
 167         /// The base metatype in the inheritance hierarchy.
 168         /// </summary>
 169         public abstract MetaType InheritanceBase { get; }
 170         /// <summary>
 171         /// The type that is the default of the inheritance hierarchy.
 172         /// </summary>
 173         public abstract MetaType InheritanceDefault { get; }
 174         /// <summary>
 175         /// Gets the MetaType for an inheritance sub type.
 176         /// </summary>
 177         /// <param name="type">The root or sub type of the inheritance hierarchy.</param>
 178         /// <returns>The MetaType.</returns>
 179         public abstract MetaType GetInheritanceType(Type type);
 180         /// <summary>
 181         /// Gets type associated with the specified inheritance code.
 182         /// </summary>
 183         /// <param name="code">The inheritance code</param>
 184         /// <returns>The MetaType.</returns>
 185         public abstract MetaType GetTypeForInheritanceCode(object code);
 186         /// <summary>
 187         /// Gets an enumeration of all types defined by an inheritance hierarchy.
 188         /// </summary>
 189         /// <returns>Enumeration of MetaTypes.</returns>
 190         public abstract ReadOnlyCollection<MetaType> InheritanceTypes { get; }
 191         /// <summary>
 192         /// Returns true if the MetaType or any base MetaType has an OnLoaded method.
 193         /// </summary>
 194         public abstract bool HasAnyLoadMethod { get; }
 195         /// <summary>
 196         /// Returns true if the MetaType or any base MetaType has an OnValidate method.
 197         /// </summary>
 198         public abstract bool HasAnyValidateMethod { get; }
 199         /// <summary>
 200         /// Gets an enumeration of the immediate derived types in an inheritance hierarchy.
 201         /// </summary>
 202         /// <returns>Enumeration of MetaTypes.</returns>
 203         public abstract ReadOnlyCollection<MetaType> DerivedTypes { get; }
 204         /// <summary>
 205         /// Gets an enumeration of all the data members (fields and properties).
 206         /// </summary>
 207         public abstract ReadOnlyCollection<MetaDataMember> DataMembers { get; }
 208         /// <summary>
 209         /// Gets an enumeration of all the persistent data members (fields and properties mapped into database columns).
 210         /// </summary>
 211         public abstract ReadOnlyCollection<MetaDataMember> PersistentDataMembers { get; }
 212         /// <summary>
 213         /// Gets an enumeration of all the data members that define up the unique identity of the type.
 214         /// </summary>
 215         public abstract ReadOnlyCollection<MetaDataMember> IdentityMembers { get; }
 216         /// <summary>
 217         /// Gets an enumeration of all the associations.
 218         /// </summary>
 219         public abstract ReadOnlyCollection<MetaAssociation> Associations { get; }
 220         /// <summary>
 221         /// Gets the MetaDataMember associated with the specified member.
 222         /// </summary>
 223         /// <param name="member">The CLR member.</param>
 224         /// <returns>The MetaDataMember if there is one, otherwise null.</returns>
 225         public abstract MetaDataMember GetDataMember(MemberInfo member);
 226         /// <summary>
 227         /// The method called when the entity is first loaded.
 228         /// </summary>
 229         public abstract MethodInfo OnLoadedMethod { get; }
 230         /// <summary>
 231         /// The method called to ensure the entity is in a valid state.
 232         /// </summary>
 233         public abstract MethodInfo OnValidateMethod { get; }
 234     }
 235
 236     /// <summary>
 237     /// A MetaDataMember represents the mapping between a domain object's field or property into a database table's column.
 238     /// </summary>
 239     [SuppressMessage("Microsoft.Naming", "CA1702:CompoundWordsShouldBeCasedCorrectly", MessageId = "MetaData", Justification = "The capitalization was deliberately chosen.")]
 240     public abstract class MetaDataMember {
 241         /// <summary>
 242         /// The MetaType containing this data member.
 243         /// </summary>
 244         public abstract MetaType DeclaringType { get; }
 245         /// <summary>
 246         /// The underlying MemberInfo.
 247         /// </summary>
 248         public abstract MemberInfo Member { get; }
 249         /// <summary>
 250         /// The member that actually stores this member's data.
 251         /// </summary>
 252         public abstract MemberInfo StorageMember { get; }
 253         /// <summary>
 254         /// The name of the member, same as the MemberInfo name.
 255         /// </summary>
 256         public abstract string Name { get; }
 257         /// <summary>
 258         /// The name of the column (or constraint) in the database.
 259         /// </summary>
 260         public abstract string MappedName { get; }
 261         /// <summary>
 262         /// The oridinal position of this member in the default layout of query results.
 263         /// </summary>
 264         public abstract int Ordinal { get; }
 265         /// <summary>
 266         /// The type of this member.
 267         /// </summary>
 268         [SuppressMessage("Microsoft.Naming", "CA1721:PropertyNamesShouldNotMatchGetMethods", Justification = "The contexts in which this is available are fairly specific.")]
 269         public abstract Type Type { get; }
 270         /// <summary>
 271         /// True if this member is declared by the specified type.
 272         /// </summary>
 273         /// <param name="type">Type to check.</param>
 274         public abstract bool IsDeclaredBy(MetaType type);
 275         /// <summary>
 276         /// The accessor used to get/set the value of this member.
 277         /// </summary>
 278         public abstract MetaAccessor MemberAccessor { get; }
 279         /// <summary>
 280         /// The accessor used to get/set the storage value of this member.
 281         /// </summary>
 282         public abstract MetaAccessor StorageAccessor { get; }
 283         /// <summary>
 284         /// The accessor used to get/set the deferred value of this member (without causing fetch).
 285         /// </summary>
 286         public abstract MetaAccessor DeferredValueAccessor { get; }
 287         /// <summary>
 288         /// The accessor used to get/set the deferred source of this member.
 289         /// </summary>
 290         public abstract MetaAccessor DeferredSourceAccessor { get; }
 291         /// <summary>
 292         /// True if this member is defer-loaded by default.
 293         /// </summary>
 294         public abstract bool IsDeferred { get; }
 295         /// <summary>
 296         /// True if this member is mapped to a column (or constraint).
 297         /// </summary>
 298         public abstract bool IsPersistent { get; }
 299         /// <summary>
 300         /// True if this member defines an association relationship.
 301         /// </summary>
 302         public abstract bool IsAssociation { get; }
 303         /// <summary>
 304         /// True if this member is part of the type's identity.
 305         /// </summary>
 306         public abstract bool IsPrimaryKey { get; }
 307         /// <summary>
 308         /// True if this member is automatically generated by the database.
 309         /// </summary>
 310         [SuppressMessage("Microsoft.Naming", "CA1709:IdentifiersShouldBeCasedCorrectly", MessageId = "Db", Justification = "Conforms to legacy spelling.")]
 311         public abstract bool IsDbGenerated { get; }
 312         /// <summary>
 313         /// True if this member represents the row version or timestamp.
 314         /// </summary>
 315         public abstract bool IsVersion { get; }
 316         /// <summary>
 317         /// True if this member represents the inheritance discriminator.
 318         /// </summary>
 319         public abstract bool IsDiscriminator { get; }
 320         /// <summary>
 321         /// True if this member's value can be assigned the null value.
 322         /// </summary>
 323         public abstract bool CanBeNull { get; }
 324         /// <summary>
 325         /// The type of the database column.
 326         /// </summary>
 327         [SuppressMessage("Microsoft.Naming", "CA1709:IdentifiersShouldBeCasedCorrectly", MessageId = "Db", Justification = "Conforms to legacy spelling.")]
 328         public abstract string DbType { get; }
 329         /// <summary>
 330         /// Expression defining a computed column.
 331         /// </summary>
 332         public abstract string Expression { get; }
 333         /// <summary>
 334         /// The optimistic concurrency check policy for this member.
 335         /// </summary>
 336         public abstract UpdateCheck UpdateCheck { get; }
 337         /// <summary>
 338         /// Specifies for inserts and updates when this member should be read back after the
 339         /// operation completes.
 340         /// </summary>
 341         public abstract AutoSync AutoSync { get; }
 342         /// <summary>
 343         /// The MetaAssociation corresponding to this member, or null if there is none.
 344         /// </summary>
 345         public abstract MetaAssociation Association { get; }
 346         /// <summary>
 347         /// The DataContext method used to perform load operations
 348         /// </summary>
 349         public abstract MethodInfo LoadMethod { get; }
 350     }
 351
 352     /// <summary>
 353     /// A MetaFunction represents the mapping between a context method and a database function.
 354     /// </summary>
 355     public abstract class MetaFunction {
 356         /// <summary>
 357         /// The MetaModel containing this function.
 358         /// </summary>
 359         public abstract MetaModel Model { get; }
 360         /// <summary>
 361         /// The underlying context method.
 362         /// </summary>
 363         public abstract MethodInfo Method { get; }
 364         /// <summary>
 365         /// The name of the method (same as the MethodInfo's name).
 366         /// </summary>
 367         public abstract string Name { get; }
 368         /// <summary>
 369         /// The name of the database function or procedure.
 370         /// </summary>
 371         public abstract string MappedName { get; }
 372         /// <summary>
 373         /// True if the function can be composed within a query
 374         /// </summary>
 375         [SuppressMessage("Microsoft.Naming", "CA1704:IdentifiersShouldBeSpelledCorrectly", MessageId = "Composable", Justification="Spelling is correct.")]
 376         public abstract bool IsComposable { get; }
 377         /// <summary>
 378         /// Gets an enumeration of the function parameters.
 379         /// </summary>
 380         /// <returns></returns>
 381         public abstract ReadOnlyCollection<MetaParameter> Parameters { get; }
 382         /// <summary>
 383         /// The return parameter
 384         /// </summary>
 385         public abstract MetaParameter ReturnParameter { get; }
 386         /// <summary>
 387         /// True if the stored procedure has multiple result types.
 388         /// </summary>
 389         public abstract bool HasMultipleResults { get; }
 390         /// <summary>
 391         /// An enumeration of all the known result row types of a stored-procedure.
 392         /// </summary>
 393         /// <returns>Enumeration of possible result row types.</returns>
 394         public abstract ReadOnlyCollection<MetaType> ResultRowTypes { get; }
 395     }
 396
 397     /// <summary>
 398     /// A MetaParameter represents the mapping between a method parameter and a database function parameter.
 399     /// </summary>
 400     public abstract class MetaParameter {
 401         /// <summary>
 402         /// The underlying method parameter.
 403         /// </summary>
 404         public abstract ParameterInfo Parameter { get; }
 405         /// <summary>
 406         /// The name of the parameter (same as the ParameterInfo's name).
 407         /// </summary>
 408         public abstract string Name { get; }
 409         /// <summary>
 410         /// The name of the database function's parameter.
 411         /// </summary>
 412         public abstract string MappedName { get; }
 413         /// <summary>
 414         /// The CLR type of the parameter.
 415         /// </summary>
 416         public abstract Type ParameterType { get; }
 417         /// <summary>
 418         /// The database type of the parameter.
 419         /// </summary>
 420         [SuppressMessage("Microsoft.Naming", "CA1709:IdentifiersShouldBeCasedCorrectly", MessageId = "Db", Justification = "Conforms to legacy spelling.")]
 421         public abstract string DbType { get; }
 422     }
 423
 424     /// <summary>
 425     /// A MetaAssociation represents an association relationship between two entity types.
 426     /// </summary>
 427     public abstract class MetaAssociation {
 428         /// <summary>
 429         /// The type on the other end of the association.
 430         /// </summary>
 431         public abstract MetaType OtherType { get; }
 432         /// <summary>
 433         /// The member on this side that represents the association.
 434         /// </summary>
 435         public abstract MetaDataMember ThisMember { get; }
 436         /// <summary>
 437         /// The member on the other side of this association that represents the reverse association (may be null).
 438         /// </summary>
 439         public abstract MetaDataMember OtherMember { get; }
 440         /// <summary>
 441         /// A list of members representing the values on this side of the association.
 442         /// </summary>
 443         public abstract ReadOnlyCollection<MetaDataMember> ThisKey { get; }
 444         /// <summary>
 445         /// A list of members representing the values on the other side of the association.
 446         /// </summary>
 447         public abstract ReadOnlyCollection<MetaDataMember> OtherKey { get; }
 448         /// <summary>
 449         /// True if the association is OneToMany.
 450         /// </summary>
 451         public abstract bool IsMany { get; }
 452         /// <summary>
 453         /// True if the other type is the parent of this type.
 454         /// </summary>
 455         public abstract bool IsForeignKey { get; }
 456         /// <summary>
 457         /// True if the association is unique (defines a uniqueness constraint).
 458         /// </summary>
 459         public abstract bool IsUnique { get; }
 460         /// <summary>
 461         /// True if the association may be null (key values).
 462         /// </summary>
 463         public abstract bool IsNullable { get; }
 464         /// <summary>
 465         /// True if the ThisKey forms the identity (primary key) of the this type.
 466         /// </summary>
 467         public abstract bool ThisKeyIsPrimaryKey { get; }
 468         /// <summary>
 469         /// True if the OtherKey forms the identity (primary key) of the other type.
 470         /// </summary>
 471         public abstract bool OtherKeyIsPrimaryKey { get; }
 472         /// <summary>
 473         /// Specifies the behavior when the child is deleted (e.g. CASCADE, SET NULL).
 474         /// Returns null if no action is specified on delete.
 475         /// </summary>
 476         public abstract string DeleteRule { get; }
 477         /// <summary>
 478         /// Specifies whether the object should be deleted when this association
 479         /// is set to null.
 480         /// </summary>
 481         public abstract bool DeleteOnNull { get; }
 482     }
 483
 484     /// <summary>
 485     /// A MetaAccessor
 486     /// </summary>
 487     public abstract class MetaAccessor {
 488         /// <summary>
 489         /// The type of the member accessed by this accessor.
 490         /// </summary>
 491         [SuppressMessage("Microsoft.Naming", "CA1721:PropertyNamesShouldNotMatchGetMethods", Justification = "The contexts in which this is available are fairly specific.")]
 492         public abstract Type Type { get; }
 493         /// <summary>
 494         /// Gets the value as an object.
 495         /// </summary>
 496         /// <param name="instance">The instance to get the value from.</param>
 497         /// <returns>Value.</returns>
 498         public abstract object GetBoxedValue(object instance);
 499         /// <summary>
 500         /// Sets the value as an object.
 501         /// </summary>
 502         /// <param name="instance">The instance to set the value into.</param>
 503         /// <param name="value">The value to set.</param>
 504         [SuppressMessage("Microsoft.Design", "CA1007:UseGenericsWhereAppropriate", Justification="Microsoft: Needs to handle classes and structs.")]
 505         [SuppressMessage("Microsoft.Design", "CA1045:DoNotPassTypesByReference", Justification="Unknown reason.")]
 506         public abstract void SetBoxedValue(ref object instance, object value);
 507         /// <summary>
 508         /// True if the instance has a loaded or assigned value.
 509         /// </summary>
 510         public virtual bool HasValue(object instance) {
 511             return true;
 512         }
 513         /// <summary>
 514         /// True if the instance has an assigned value.
 515         /// </summary>
 516         public virtual bool HasAssignedValue(object instance) {
 517             return true;
 518         }
 519         /// <summary>
 520         /// True if the instance has a value loaded from a deferred source.
 521         /// </summary>
 522         public virtual bool HasLoadedValue(object instance) {
 523             return false;
 524         }
 525     }
 526
 527     /// <summary>
 528     /// A strongly-typed MetaAccessor. Used for reading from and writing to
 529     /// CLR objects.
 530     /// </summary>
 531     /// <typeparam name="T">The type of the object</typeparam>
 532     /// <typeparam name="V">The type of the accessed member</typeparam>
 533     public abstract class MetaAccessor<TEntity, TMember> : MetaAccessor {
 534         /// <summary>
 535         /// The underlying CLR type.
 536         /// </summary>
 537         public override Type Type {
 538             get { return typeof(TMember); }
 539         }
 540         /// <summary>
 541         /// Set the boxed value on an instance.
 542         /// </summary>
 543         public override void SetBoxedValue(ref object instance, object value) {
 544             TEntity tInst = (TEntity)instance;
 545             this.SetValue(ref tInst, (TMember)value);
 546             instance = tInst;
 547         }
 548         /// <summary>
 549         /// Retrieve the boxed value.
 550         /// </summary>
 551         public override object GetBoxedValue(object instance) {
 552             return this.GetValue((TEntity)instance);
 553         }
 554         /// <summary>
 555         /// Gets the strongly-typed value.
 556         /// </summary>
 557         public abstract TMember GetValue(TEntity instance);
 558         /// <summary>
 559         /// Sets the strongly-typed value
 560         /// </summary>
 561         [SuppressMessage("Microsoft.Design", "CA1045:DoNotPassTypesByReference", MessageId = "0#", Justification = "Unknown reason.")]
 562         public abstract void SetValue(ref TEntity instance, TMember value);
 563     }
 564 }