The references are unidirectional. The table (StoreProduct) for this entity is actually a join table that has these fields:
- Store_id
- Product_id
- ExtraBit
So I went with an entity having a compoundID (store_id and product_id) and the ExtraBit is just a string:
public class StoreProduct
{
protected StoreProduct():this(null,null,null){ }
public StoreProduct(Store c_Store, Product c_Product, String c_ExtraBit)
{
Store = c_Store;
Product = c_Product;
ExtraBit = c_ExtraBit;
}
public virtual int Product_id { get; set; }
public virtual int Store_id { get; set; }
public virtual Store Store { get; set; }
public virtual Product Product { get; set; }
public virtual String ExtraBit { get; set; }
public override int GetHashCode()
{
return Store.GetHashCode() + Product.GetHashCode();
}
public override bool Equals(object obj)
{
StoreProduct obj_StoreProduct;
obj_StoreProduct = obj as StoreProduct;
if (obj_StoreProduct == null)
{
return false;
}
if (obj_StoreProduct.Product != this.Product && obj_StoreProduct.Store != this.Store)
{
return false;
}
return true;
}
}
And the mapping:
public class Order_DetailMap : ClassMap<StoreProduct>
{
public Order_DetailMap()
{
Table("StoreProduct");
LazyLoad();
CompositeId().KeyProperty(x => x.Store_id).KeyProperty(x => x.Product_id);
References(x => x.Store).ForeignKey("Store_id").Cascade.All();
References(x => x.Product).ForeignKey("Product_id").Cascade.All();
Map(x => x.ExtraBit);
}
}
It doesn't work though, when I tried saving the StoreProduct and its newly created Store and product. Can anyone help? Here is some output:
Unhandled Exception: System.ArgumentOutOfRangeException: Index was out of range.
Must be non-negative and less than the size of the collection.
Parameter name: index
at System.ThrowHelper.ThrowArgumentOutOfRangeException()
at System.Data.SQLite.SQLiteParameterCollection.GetParameter(Int32 index)
at System.Data.Common.DbParameterCollection.System.Collections.IList.get_Item
(Int32 index)
at NHibernate.Type.Int32Type.Set(IDbCommand rs, Object value, Int32 index) in
d:\CSharp\NH\NH\nhibernate\src\NHibernate\Type\Int32Type.cs:line 60
at NHibernate.Type.NullableType.NullSafeSet(IDbCommand cmd, Object value, Int
32 index) in d:\CSharp\NH\NH\nhibernate\src\NHibernate\Type\NullableType.cs:line
180
at NHibernate.Type.NullableType.NullSafeSet(IDbCommand st, Object value, Int3
2 index, ISessionImplementor session) in d:\CSharp\NH\NH\nhibernate\src\NHiberna
te\Type\NullableType.cs:line 139
at NHibernate.Type.ComponentType.NullSafeSet(IDbCommand st, Object value, Int
32 begin, ISessionImplementor session) in d:\CSharp\NH\NH\nhibernate\src\NHibern
ate\Type\ComponentType.cs:line 221
at NHibernate.Persister.Entity.AbstractEntityPersister.Dehydrate(Object id, O
bject[] fields, Object rowId, Boolean[] includeProperty, Boolean[][] includeColu
mns, Int32 table, IDbCommand statement, ISessionImplementor session, Int32 index
) in d:\CSharp\NH\NH\nhibernate\src\NHibernate\Persister\Entity\AbstractEntityPe
rsister.cs:line 2418
Edit: Thanks to the help bellow I seem to have a decent solution:
Store Mapping and Class:
namespace compoundIDtest.Domain.Mappings
{
public class StoreMap : ClassMap<Store>
{
public StoreMap()
{
Id(x => x.Id).Column("Store_id");
Map(x => x.Name);
HasMany(x => x.Staff)
.Inverse()
.Cascade.All();
HasManyToMany(x => x.Products)
.Cascade.All()
.Table("StoreProduct");
}
}
}
namespace compoundIDtest.Domain.Entities
{
public class Store
{
public virtual int Id { get; private set; }
public virtual string Name { get; set; }
public virtual IList<Product> Products { get; set; }
public virtual IList<Employee> Staff { get; set; }
public virtual IList<StoreProduct> StoreProducts { get; set; }
public Store()
{
Products = new List<Product>();
Staff = new List<Employee>();
}
public virtual void AddProduct(Product product)
{
product.StoresStockedIn.Add(this);
Products.Add(product);
}
public virtual void AddEmployee(Employee employee)
{
employee.Store = this;
Staff.Add(employee);
}
public override int GetHashCode()
{
return Name.GetHashCode();
}
public override bool Equals(object obj)
{
Store obj_Store;
obj_Store = obj as Store;
if (obj_Store == null)
{
return false;
}
if (obj_Store.Name != this.Name)
{
return false;
}
return true;
}
}
}
Product Mapping And Class
namespace compoundIDtest.Domain.Mappings
{
public class ProductMap : ClassMap<Product>
{
public ProductMap()
{
Id(x => x.Id).Column("Product_id");
Map(x => x.Name);
Map(x => x.Price);
HasManyToMany(x => x.StoresStockedIn)
.Cascade.All()
.Inverse()
.Table("StoreProduct");
}
}
}
namespace compoundIDtest.Domain.Entities
{
public class Product
{
public virtual int Id { get; private set; }
public virtual string Name { get; set; }
public virtual double Price { get; set; }
public virtual IList<Store> StoresStockedIn { get; set; }
public virtual IList<StoreProduct> StoreProducts { get; set; }
public Product()
{
StoresStockedIn = new List<Store>();
StoreProducts = new List<StoreProduct>();
}
public override int GetHashCode()
{
return Name.GetHashCode();
}
public override bool Equals(object obj)
{
Product obj_Product;
obj_Product = obj as Product;
if (obj_Product == null)
{
return false;
}
if (obj_Product.Name != this.Name)
{
return false;
}
return true;
}
}
}
And StoreProduct
namespace compoundIDtest.Domain.Mappings
{
public class Order_DetailMap : ClassMap<StoreProduct>
{
public Order_DetailMap()
{
Table("StoreProduct");
LazyLoad();
CompositeId().KeyReference(x => x.Store, "Store_id").KeyReference(x => x.Product, "Product_id");
References(x => x.Store, "Store_id").Not.Update().Not.Insert().Cascade.All();
References(x => x.Product, "Product_id").Not.Update().Not.Insert().Cascade.All();
Map(x => x.ExtraBit);
}
}
}
namespace compoundIDtest.Domain.Entities
{
public class StoreProduct
{
public StoreProduct(){}
public virtual Store Store { get; set; }
public virtual Product Product { get; set; }
public virtual String ExtraBit { get; set; }
public override int GetHashCode()
{
if (this.ExtraBit != null)
{
return Store.GetHashCode() + Product.GetHashCode() + ExtraBit.GetHashCode();
}
return Store.GetHashCode() + Product.GetHashCode();
}
public override bool Equals(object obj)
{
StoreProduct obj_StoreProduct;
obj_StoreProduct = obj as StoreProduct;
if (obj_StoreProduct == null)
{
return false;
}
if (obj_StoreProduct.Product != this.Product && obj_StoreProduct.Store != this.Store && obj_StoreProduct.ExtraBit != this.ExtraBit)
{
return false;
}
return true;
}
}
}
And here is code for an app to test the above:
using System;
using System.IO;
using compoundIDtest.Domain.Entities;
using FluentNHibernate.Cfg;
using FluentNHibernate.Cfg.Db;
using NHibernate;
using NHibernate.Cfg;
using NHibernate.Tool.hbm2ddl;
using FluentNHibernate.Conventions;
namespace compoundIDtest
{
class Program
{
private const string DbFile = "firstProgram.db";
static void Main()
{
// create our NHibernate session factory
var sessionFactory = CreateSessionFactory();
using (var session = sessionFactory.OpenSession())
{
// populate the database
using (var transaction = session.BeginTransaction())
{
// create a couple of Stores each with some Products and Employees
var barginBasin = new Store { Name = "Bargin Basin" };
var superMart = new Store { Name = "SuperMart" };
var CornerShop = new Store { Name = "Corner Shop" };
var potatoes = new Product { Name = "Potatoes", Price = 3.60 };
var fish = new Product { Name = "Fish", Price = 4.49 };
var milk = new Product { Name = "Milk", Price = 0.79 };
var bread = new Product { Name = "Bread", Price = 1.29 };
var cheese = new Product { Name = "Cheese", Price = 2.10 };
var waffles = new Product { Name = "Waffles", Price = 2.41 };
var poison = new Product { Name = "Poison", Price = 1.50 };
var daisy = new Employee { FirstName = "Daisy", LastName = "Harrison" };
var jack = new Employee { FirstName = "Jack", LastName = "Torrance" };
var sue = new Employee { FirstName = "Sue", LastName = "Walkters" };
var bill = new Employee { FirstName = "Bill", LastName = "Taft" };
var joan = new Employee { FirstName = "Joan", LastName = "Pope" };
var storeproduct = new StoreProduct { Store = CornerShop, Product = poison, ExtraBit = "Extra Bit"};
//session.SaveOrUpdate(CornerShop);
//session.SaveOrUpdate(poison);
session.Save(storeproduct);
// add products to the stores, there's some crossover in the products in each
// store, because the store-product relationship is many-to-many
AddProductsToStore(barginBasin, potatoes, fish, milk, bread, cheese);
AddProductsToStore(superMart, bread, cheese, waffles);
// add employees to the stores, this relationship is a one-to-many, so one
// employee can only work at one store at a time
AddEmployeesToStore(barginBasin, daisy, jack, sue);
AddEmployeesToStore(superMart, bill, joan);
// save both stores, this saves everything else via cascading
session.SaveOrUpdate(barginBasin);
session.SaveOrUpdate(superMart);
//session.SaveOrUpdate(CornerShop);
//session.SaveOrUpdate(poison);
//session.SaveOrUpdate(storeproduct);
transaction.Commit();
}
}
using (var session = sessionFactory.OpenSession())
{
// retreive all stores and display them
using (var transaction = session.BeginTransaction())
{
var products = session.CreateCriteria(typeof(Product))
.List<Product>();
foreach (var product in products)
{
product.Price = 100;
session.SaveOrUpdate(product);
}
var storeproducts = session.CreateCriteria(typeof(StoreProduct)).List<StoreProduct>();
foreach (StoreProduct storeproduct in storeproducts)
{
if (storeproduct.Store.Name == "SuperMart")
{
storeproduct.ExtraBit = "Thank you, come again";
}
session.SaveOrUpdate(storeproduct);
}
transaction.Commit();
}
}
Console.ReadKey();
}
private static ISessionFactory CreateSessionFactory()
{
return Fluently.Configure()
.Database(SQLiteConfiguration.Standard
.UsingFile(DbFile))
.Mappings(m =>
m.FluentMappings.AddFromAssemblyOf<Program>())
.ExposeConfiguration(BuildSchema)
.BuildSessionFactory();
}
private static void BuildSchema(Configuration config)
{
// delete the existing db on each run
if (File.Exists(DbFile))
File.Delete(DbFile);
// this NHibernate tool takes a configuration (with mapping info in)
// and exports a database schema from it
new SchemaExport(config)
.Create(false, true);
}
private static void WriteStorePretty(Store store)
{
Console.WriteLine(store.Name);
Console.WriteLine(" Products:");
foreach (var product in store.Products)
{
Console.WriteLine(" " + product.Name);
}
Console.WriteLine(" Staff:");
foreach (var employee in store.Staff)
{
Console.WriteLine(" " + employee.FirstName + " " + employee.LastName);
}
Console.WriteLine();
}
public static void AddProductsToStore(Store store, params Product[] products)
{
foreach (var product in products)
{
store.AddProduct(product);
}
}
public static void AddEmployeesToStore(Store store, params Employee[] employees)
{
foreach (var employee in employees)
{
store.AddEmployee(employee);
}
}
}
}