私は .NET 2.0 を使用していますが、Thread がタイムアウトした場合、finally ブロックが実行されていないようです。たとえば、「子スレッドがタイムアウトしました...」というメッセージが表示された場合、「最終的にブロックが開始されました...」というメッセージは表示されません。これは、データベース オブジェクト (Oracle.DataAccess) が適切にクリーンアップされていない可能性があることを意味します。子スレッド内でクリーンアップを強制する方法はありますか、またはクリーンアップをメイン スレッドに移動し、データベース オブジェクトを子スレッドに渡す必要がありますか?
private void runThread(string strSP, object objThreadParameter)
{
try
{
bool blnThreadCompletedOK = true;
Thread threadHelper = new Thread(getData);
threadHelper.Start(objThreadParameter);
// Wait for called thread.
blnThreadCompletedOK = threadHelper.Join(THREAD_TIMEOUT);
if (blnThreadCompletedOK)
{
// Thread has completed and should have stopped running.
// i.e. the thread has processed normally or an exception has been copied to the objExceptionThread object.
if (objExceptionThread != null)
{
throw objExceptionThread;
}
}
else
{
System.Diagnostics.EventLog.WriteEntry("Main thread", "Child Thread Timed Out...", System.Diagnostics.EventLogEntryType.Warning);
// Main thread has timed out waiting for the child thread. Likely the child thread is still running.
if (threadHelper.IsAlive)
{
threadHelper.Abort(); // This will trigger the exception handling in the child thread and cause the finally
// block to be executed.
}
throw (new Exception("The call to " + strSP + "() timed out as it exceeded " + (THREAD_TIMEOUT / 1000).ToString() + " seconds"));
}
}
catch (Exception exc)
{
throw new PivotalApplicationException(exc.Message, exc, mrsysSystem);
}
}
private void getData(object objThreadParameter)
{
OracleCommand oraCmd = null;
OracleConnection oraConn = null;
OracleDataReader dr = null;
try
{
// Initialization.
int intMAX_RETRIES = 20; // Maximum number of retries.
int intRETRY_DROP_POOL = 5; // At some point, if connections are still failing, try clearing the pool.
// Other initialization stuff...
// Now execute the SP.
for (int i = 1; i <= intMAX_RETRIES; i++)
{
try
{
try
{
// Setup Oracle connection and initialize Oracle command object.
getOracleConnection(out oraConn, connString);
}
catch (Exception exc)
{
throw new Exception("Error in getData() setting up connection - " + exc.Message);
}
try
{
oraCmd = new OracleCommand(strSP, oraConn);
setupCommand (out oraCmd);
}
catch (Exception exc)
{
throw new Exception("Error in getData() setting up parameters - " + exc.Message);
}
try
{
dr = oraCmd.ExecuteReader();
break; // Success, so, leave the for loop.
}
catch (Exception exc)
{
throw new Exception("Error in getData() executing command.\n\n" + strParametersMsg + " \n\n" + exc.Message);
}
}
catch (Exception excInner)
{
if (i >= intMAX_RETRIES)
{
throw new Exception(excInner.Message);
}
else
{
// Cleanup oraCmd, oraConn, oraDr...
}
}
}
try
{
// Process results...
}
catch (Exception exc)
{
throw new Exception("Error in getData() processing results - " + exc.Message);
}
// Now set the variables that are shared between the Main thread and this thread...
}
catch (Exception exc)
{
logMessage(exc.Source + " " + exc.Message);
objExceptionThread = exc; // Initialize exception in Main Thread...
}
finally
{
System.Diagnostics.EventLog.WriteEntry("Child Thread", "Finally block started...", System.Diagnostics.EventLogEntryType.Warning);
// With .NET 2.0 and later, the finally block should always be executed correctly for a Thread.Abort()
if (!(dr == null))
{
dr.Dispose();
}
if (!(oraCmd == null))
{
oraCmd.Dispose();
}
if (!(oraConn == null))
{
oraConn.Close();
oraConn.Dispose();
}
System.Diagnostics.EventLog.WriteEntry("Child Thread", "Finally block completed...", System.Diagnostics.EventLogEntryType.Warning);
}
}