public static bool TxCommit()
{
if (_transaction.State.Equals(TransactionState.ABORTED))
{
// Some server failed
return(false);
}
if (Transaction.ACCESSEDSERVERS.Count > 0)
{
bool success = false;
List <string> participants = Transaction.ACCESSEDSERVERS;
string coordURL = participants.ElementAt(0);
participants.RemoveAt(0);
IDatastoreOps datastore = (IDatastoreOps)Activator.GetObject(
typeof(IDatastoreOps),
coordURL + "DatastoreOps");
Console.WriteLine("PadiDstm.TxCommit: Before commit in Datastore");
success = datastore.commit(Transaction.TXID, participants);
Console.WriteLine("PadiDstm.TxCommit: After commit in Datastore");
_transaction = null;
return(success);
}
_transaction = null;
return(true);
}
/**
* CreatePadInt
* @param uid is a global unique identifier for the object in the system
* @return PadInt an object representing to the client App what a PadInt is
*
* CreatePadInt computes the server number based on the uid provided and the number
* of servers available in the current transaction. It is guaranteed by the system
* that the object with uid is in the server.
**/
public static PadInt CreatePadInt(int uid)
{
if (_transaction.State.Equals(TransactionState.ABORTED))
{
// Some server failed
Console.WriteLine("Trying to access padint uid=" + uid + " denied because of server failure");
return(null);
}
int serverNumber = computeDatastore(uid);
string serverURL = Servers.AvailableServers[serverNumber];
IDatastoreOps datastore = (IDatastoreOps)Activator.GetObject(
typeof(IDatastoreOps),
serverURL + "DatastoreOps");
try
{
bool success = datastore.createPadInt(uid, Transaction.TXID, Client_Url);
if (success)
{
Console.WriteLine("PadiDstm.CreatePadInt TRUE");
PadInt padint = new PadInt(uid, serverURL);
Transaction.addAccessedServer(serverURL);
return(padint);
}
else
{
return(null);
}
}
// If failed catch exception or special number int32.MIN to detect that the server
// failed and tell the master to stabilize the system
catch (SocketException)
{
manageFailedServer(serverURL, serverNumber);
return(AccessPadInt(uid));
}
catch (System.IO.IOException)
{
manageFailedServer(serverURL, serverNumber);
return(AccessPadInt(uid));
}
catch (ServerException)
{
manageFailedServer(serverURL, serverNumber);
return(AccessPadInt(uid));
}
}
/**
* AccessPadInt
* @param uid is a global unique identifier for the object in the system
* @return PadInt an object representing to the client App what a PadInt is
*
* AccessPadInt computes the server number based on the uid provided and the number
* of servers available in the current transaction. It is guaranteed by the system
* that the object with uid is in the server.
**/
public static PadInt AccessPadInt(int uid)
{
if (_transaction.State.Equals(TransactionState.ABORTED))
{
// Some server failed
Console.WriteLine("Trying to access padint uid=" + uid + " denied because of server failure");
PadInt padint = new PadInt(uid, "");
return(padint);
}
int serverNumber = computeDatastore(uid);
string serverURL = Servers.AvailableServers[serverNumber];
IDatastoreOps datastore = (IDatastoreOps)Activator.GetObject(
typeof(IDatastoreOps), serverURL + "DatastoreOps");
try
{
bool success = datastore.accessPadInt(uid);
if (success)
{
Console.WriteLine("PadiDstm.AccessPadInt TRUE");
PadInt padint = new PadInt(uid, serverURL);
Transaction.addAccessedServer(serverURL);
return(padint);
}
else
{
//Returns null if the object does not exist already.
return(null);
}
}
catch (SocketException)
{
manageFailedServer(serverURL, serverNumber);
return(AccessPadInt(uid));
}
catch (System.IO.IOException)
{
manageFailedServer(serverURL, serverNumber);
return(AccessPadInt(uid));
}
catch (ServerFailedException)
{
manageFailedServer(serverURL, serverNumber);
return(AccessPadInt(uid));
}
}
