NH-4008 - Use FirebirdClient ClearPool without reflection.

Author: ngbrown

src/NHibernate.Driver.FirebirdClient/Driver/FirebirdClientDriver.cs

@@ -3,8 +3,8 @@
 using System.Data;
 using System.Data.Common;
 using System.Linq;
-using System.Reflection;
 using System.Text.RegularExpressions;
+using FirebirdSql.Data.FirebirdClient;
 using NHibernate.Dialect;
 using NHibernate.SqlCommand;
 using NHibernate.SqlTypes;
@@ -40,12 +40,12 @@ public override string NamedPrefix
 
 		public override DbConnection CreateConnection()
 		{
-			return new FirebirdSql.Data.FirebirdClient.FbConnection();
+			return new FbConnection();
 		}
 
 		public override DbCommand CreateCommand()
 		{
-			return new FirebirdSql.Data.FirebirdClient.FbCommand();
+			return new FbCommand();
 		}
 
 
@@ -105,39 +105,24 @@ private string GetFbTypeFromDbType(DbType dbType)
 			return _fbDialect.GetCastTypeName(new SqlType(dbType));
 		}
 
-		private static volatile MethodInfo _clearPool;
-		private static volatile MethodInfo _clearAllPools;
-
 		/// <summary>
 		/// Clears the connection pool.
 		/// </summary>
 		/// <param name="connectionString">The connection string of connections for which to clear the pool.
 		/// <c>null</c> for clearing them all.</param>
 		public void ClearPool(string connectionString)
 		{
-			// In case of concurrent threads, may initialize many times. We do not care.
-			// Members are volatile for avoiding it gets used while its constructor is not yet ended.
-			if (_clearPool == null || _clearAllPools == null)
-			{
-				using (var clearConnection = CreateConnection())
-				{
-					var connectionType = clearConnection.GetType();
-					_clearPool = connectionType.GetMethod("ClearPool") ?? throw new InvalidOperationException("Unable to resolve ClearPool method.");
-					_clearAllPools = connectionType.GetMethod("ClearAllPools") ?? throw new InvalidOperationException("Unable to resolve ClearAllPools method.");
-				}
-			}
-
 			if (connectionString != null)
 			{
 				using (var clearConnection = CreateConnection())
 				{
 					clearConnection.ConnectionString = connectionString;
-					_clearPool.Invoke(null, new object[] {clearConnection});
+					FbConnection.ClearPool((FbConnection)clearConnection);
 				}
 				return;
 			}
 
-			_clearAllPools.Invoke(null, new object[0]);
+			FbConnection.ClearAllPools();
 		}
 	}
 }