dataprovider.cs

SharpNuke源代码

using System;
using System.Data;
using System.Reflection;
using System.Web.Caching;

using DotNetNuke.Common.Utilities;
using DotNetNuke.Framework.Providers;
using DotNetNuke.Services.Cache;

//
// DotNetNuke -  http://www.dotnetnuke.com
// Copyright (c) 2002-2005
// by Shaun Walker ( [e-mail] ) of Perpetual Motion Interactive Systems Inc. ( http://www.perpetualmotion.ca )
//
// 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.
//


namespace DotNetNuke.Services.Cache.BroadcastPollingCachingProvider.Data
{
	
	public abstract class DataProvider
	{
		
		#region "Shared/Static Methods"
		// provider constants - eliminates need for Reflection later
		private const string providerType = "data"; // maps to <sectionGroup> in web.config
		private const string providerNamespace = "DotNetNuke.Services.Cache.BroadcastPollingCachingProvider.Data"; // project namespace
		private const string providerAssemblyName = "DotNetNuke.Caching.BroadcastPollingCachingProvider"; // project assemblyname
		
		public static DataProvider Instance()
		{
			string cacheKey = providerNamespace + "." + providerType + "provider";
			
			// Use the cache because the reflection used later is expensive
			ConstructorInfo constructorInfo = DataCache.GetCache(cacheKey) as ConstructorInfo;
			
			if (constructorInfo == null)
			{
				// Get the provider configuration based on the type
				ProviderConfiguration providerConfiguration = ProviderConfiguration.GetProviderConfiguration(providerType);
				
				// The assembly should be in \bin or GAC, so we simply need to get an instance of the type
								
				// Override the typename if a ProviderName is specified ( this allows the application to load a different DataProvider assembly for custom modules )
				string typeName = providerNamespace + "." + providerConfiguration.DefaultProvider + ", " + providerAssemblyName + "." + providerConfiguration.DefaultProvider;
				
				// Use reflection to store the constructor of the class that implements DataProvider
				Type type = Type.GetType(typeName, true);
				constructorInfo = type.GetConstructor(System.Type.EmptyTypes);
				
				// Insert the type into the cache
				DataCache.SetCache(cacheKey, constructorInfo);
			}
			
			return ((DataProvider) constructorInfo.Invoke(null));
		}
		
		#endregion
		
		#region "Abstract Methods"
		
		public abstract IDataReader GetCachedObject(string key);
		public abstract void AddCachedObject (string key, string value, string serverName);
		public abstract void DeleteCachedObject (string key);
		
		public abstract int AddBroadcast(string broadcastType, string broadcastMessage, string serverName);
		public abstract IDataReader GetBroadcasts(string serverName);
		
		#endregion
		
	}
	
}