/// <summary>
/// Decreases the number of active used connections
/// </summary>
internal void DecreaseActiveConnectionCount(DatabaseContainer database)
{
lock (activeConnectionLock)
{
activeConnectionCount--;
if (activeConnectionCount < 0)
{
throw new Exception(DataAccessResources.ParallelMultithreadingMalfunctionMessage);
}
lock (connections)
{
database.InUse = false;
}
Monitor.Pulse(activeConnectionLock);
}
}
/// <summary>
/// Initializes a new instance of the DataBufferResourceLock class
/// </summary>
/// <param name="buffer">The Queue into which to put the connection after disposal of this lock</param>
/// <param name="target">The container object used to cache the connection</param>
/// <param name="innerLock">the inner lock of this resource lock</param>
public DataBufferResourceLock(DatabaseConnectionBuffer buffer, DatabaseContainer target, IResourceLock innerLock)
: this(buffer, target)
{
InnerLock = innerLock;
}
/// <summary>
/// Initializes a new instance of the DataBufferResourceLock class
/// </summary>
/// <param name="buffer">The Queue into which to put the connection after disposal of this lock</param>
/// <param name="target">The container object used to cache the connection</param>
public DataBufferResourceLock(DatabaseConnectionBuffer buffer, DatabaseContainer target)
{
this.buffer = buffer;
this.target = target;
}
/// <summary>
/// Gets an available Database Connection from the pool of available connections
/// </summary>
/// <param name="useTransaction">indicates whether to begin a transaction for the returned database connection</param>
/// <param name="database">the database that is available for usage</param>
/// <returns>a connection that is unused at the moment</returns>
public IResourceLock AcquireConnection(bool useTransaction, out IDbWrapper database)
{
string threadId = Thread.CurrentThread.LocalOwner();
DatabaseContainer db;
IResourceLock inner = null;
while (!disposing)
{
try
{
lock (connections)
{
var tmp =
(from t in connections
where !t.InUse && !t.Disposed && t.ThreadId == threadId
select t).FirstOrDefault
();
if (tmp != null)
{
tmp.InUse = true;
tmp.LastUsage = DateTime.Now;
}
db = tmp;
}
if (db == null)
{
db = new DatabaseContainer
{
Database = factory.LoadPlugin <IDbWrapper>(DataAccessResources.ParallelDummyInstanceName,
databaseConstructor,
false),
LastUsage = DateTime.Now,
InUse = true,
ThreadId = threadId
};
lock (connections)
{
connections.Add(db);
}
}
if (useTransaction)
{
inner = db.Database.AcquireTransaction();
}
database = db.Database;
lock (activeConnectionLock)
{
activeConnectionCount++;
}
OnConnectionAcquiring(database);
return(new DataBufferResourceLock(this, db, inner));
}
catch (Exception ex)
{
LogEnvironment.LogEvent(ex.Message, LogSeverity.Error, "DataAccess");
}
}
database = null;
return(null);
}