//@Override
public bool removeAppointment(int seqNumberInt)
{
//call by both remote and local hosts
//because in C# XmlRpcServer Library stoping the servicing has an error we refuse the incoming requests if the server
//is not in its online mode.
if (!ServerStatus.getServerStatus())
{
return(false);
}
Integer seqNumber = new Integer(seqNumberInt);
foreach (Appointment appointment in this.appointmentsList)
{
if (appointment.getSequentialNumber() == seqNumber.intValue())
{
this.appointmentsList.Remove(appointment);
if (!this.appointmentsList.Exists(temp => temp == appointment)) //if the remove was successful?
{
this.setLastModified();
this.updateLocalDatabase();
return(true);
}
else
{
return(false);
}
}
}
return(true);
}
//@Override
public bool addMe(String newHostUrl, int port) //add a signOn host
{
//this function must not be static because it is needed to call by XML-RPC
//this function will call by a client on another host
//the client will send its own URL and port to register as a new host on this machine
//and then the client will receive 'true' if the addition was successful or 'false' if the addition was failed
//because in C# XmlRpcServer Library stoping the servicing has an error we refuse the incoming requests if the server
//is not in its online mode.
if (!ServerStatus.getServerStatus())
{
return(false);
}
try{
//check for iterated(repited) host
for (int index = 0; index < hostsAddresses.Count; index++)
{
if (hostsAddresses[index].getHostUrl().Equals(newHostUrl) && hostsAddresses[index].getPort() == port)
{
return(true); //it means at the previous signoff the address of this host has not removed successfully
}
}
HostUrl hostUrl = new HostUrl(newHostUrl, port);
hostsAddresses.Add(hostUrl);
return(true);
//note: if the add procedure be successful, then the a true value will be send
}catch (System.Exception) {
//Console.WriteLine("Joining a new host has crached, maybe entered URL or port has a problem.");
//Console.WriteLine(e.Message);
return(false);//if the adding process fail in any cases, this false value will show this failure
}
}
//@Override
public bool removeMe(String oldHostUrl, int port) //Remove a signOff host
{
//this function must not be static because it is needed to call by XML-RPC
//this function will call by a client on another host
//the client will send its own URL and port to unregister as a signed on host and goes to sign off
//and then the client will receive 'true' if the elimination was successful or 'false' if the elimination was failed
//because in C# XmlRpcServer Library stoping the servicing has an error we refuse the incoming requests if the server
//is not in its online mode.
if (!ServerStatus.getServerStatus())
{
return(false);
}
try{
//check to find the host in the list
for (int index = 0; index < hostsAddresses.Count; index++)
{
if (hostsAddresses[index].getHostUrl().Equals(oldHostUrl) && hostsAddresses[index].getPort() == port)
{
hostsAddresses.RemoveRange(index, 1);
break;
}
}
return(true);
}
catch (System.Exception)
{
}
return(false);//if the removing process fail in any cases, this false value will show this failure
}
//@Override
public bool modifyAppointment(int seqNumberInt, String newDateTimeString, int newSecDurationInt, String newHeader, String newComment)
{
//call by both remote and local hosts
//because in C# XmlRpcServer Library stoping the servicing has an error we refuse the incoming requests if the server
//is not in its online mode.
if (!ServerStatus.getServerStatus())
{
return(false);
}
Integer seqNumber;
Date newDateTime;
Integer newSecDuration;
try
{
seqNumber = new Integer(seqNumberInt);
newDateTime = new Date(newDateTimeString);
newSecDuration = new Integer(newSecDurationInt);
}
catch (System.Exception)
{
return(false);
}
if (seqNumber.intValue() < 1)
{
return(false);
}
else if (newSecDuration.intValue() < 1)
{
return(false);
}
foreach (Appointment appointment in this.appointmentsList)
{
if (appointment.getSequentialNumber() == seqNumber.intValue())
{
try
{
appointment.setDateTime(newDateTime);
appointment.setSecDuration(newSecDuration.intValue());
appointment.setHeader(newHeader);
appointment.setComment(newComment);
this.setLastModified();
this.updateLocalDatabase();
return(true);
}
catch (System.ArgumentOutOfRangeException) //For setDuration
{
return(false);
}
}
}
//if it couldn't find this appointment must add this to the list!
return(addNewAppointment(seqNumberInt, newDateTimeString, newSecDurationInt, newHeader, newComment));
}
//@Override
public int createNewAppointment(String dateTimeString, int secDurationInt, String header, String comment) //call by this client but throw XML-RPC
{
//call by the client of the current machine to make a new appointment
//it must return unique sequence number of the new appointment or -1 if it fail to add
//because in C# XmlRpcServer Library stoping the servicing has an error we refuse the incoming requests if the server
//is not in its online mode.
if (!ServerStatus.getServerStatus())
{
return(-1);
}
Date dateTime;
Integer secDuration;
try
{
dateTime = new Date(dateTimeString);
secDuration = new Integer(secDurationInt);
}
catch (System.Exception e)
{
Console.WriteLine(e.Message);
return(-1);
}
//throwing an exception has sence or meaning here
//because this function will call locally
if (secDuration.intValue() < 1)
{
throw new System.ArgumentOutOfRangeException("The seconds of duration[secDuration] must be greater than 0.");
}
//Create a new seqNumber and add the appointment to the array list!
try
{
SequentialNumber sqn = new SequentialNumber();
Appointment appointment = new Appointment(sqn, dateTime, secDuration.intValue(), header, comment);
this.appointmentsList.Add(appointment);
Console.WriteLine("\n_______________________________");
Console.WriteLine("You have made a new appointment on this host successfully.\n" + appointment.ToString());
this.setLastModified();
this.updateLocalDatabase();
return(sqn.getSequentialNumber());
}
catch (System.IndexOutOfRangeException e) //for creating sequential number
{
Console.WriteLine(e.Message);
return(-1);
}
}
//@Override
public bool addPemissionAccepted(String replierId, int replierLogicalClock, String replierHostUrl, int replierHostPort, String requesterId, int requesterLogicalClock)
{
//the clock will manage here too
//The first 2 objects used for correcting the clock
//The third one used for deleting the host from the tail list ! and not from the queue
//The last 2 objects are used for checking true answering
//this will call by other clients to send [rep<id,clock> --to--> req<id',clock'>] actually OK message!
//when they want to send a OK reply to our previous request they must call this function
//this function will remove RequestObjects from the tail list
try{
if (!ServerStatus.getServerStatus())
{
return(false);
}
if (currentAddRequest != null)
{
long requesterIdL = 0;
HostUrl hostUrl = null;
try
{
requesterIdL = Convert.ToInt64(requesterId);
hostUrl = new HostUrl(replierHostUrl, replierHostPort);
}
catch (Exception)
{
return(false);
}
//correcting Clock
ExtendedLamportClockObject ELC = new ExtendedLamportClockObject(requesterIdL, requesterLogicalClock); //for correcting logical clock after receive
if (currentAddRequest.getELCO().compare(ELC) == 0) //if the replier send the reply for the current request
{
lock (this)
{
currentAddRequest.removeNode(hostUrl);
}
hostUrl = null;
ELC = null;
}
return(true);
}
return(false);
}catch (Exception) { return(false); }
}
//@Override
public String syncRequest(String lastModificationString)
{
//Called by remote hosts to get list of appointments for synchronization
//At first we wanted to optimize it by last modification time but because it was not said in the assignment sheet we
//decided to drop this section!
//because in C# XmlRpcServer Library stopping the servicing has an error we refuse the incoming requests if the server
//is not in its online mode.
if (!ServerStatus.getServerStatus())
{
return(null);
}
//Date lastModification = new Date(lastModificationString);
return(this.appointmentsSerialize());
}
//@Override
public String joinRequest(String newHostUrl, int port)
{
//Console.WriteLine("\nNew joining request from : "+newHostUrl+" port: "+port + " has been received.");
//this function must not be static because it is needed to call by XML-RPC
//this function will call by a client on another host
//the client will send its own URL and port
//and then the client will receive a list of all hosts
//because in C# XmlRpcServer Library stoping the servicing has an error we refuse the incoming requests if the server
//is not in its online mode.
if (!ServerStatus.getServerStatus())
{
return(null);
}
try
{
bool flag = true;
HostUrl hostUrl = new HostUrl(newHostUrl, port);
//check for iterated(repited) host
for (int index = 0; index < hostsAddresses.Count && flag; index++)
{
if (hostsAddresses[index].getHostUrl().Equals(newHostUrl) && hostsAddresses[index].getPort() == port)
{
flag = false;
}
}
if (flag)
{
hostsAddresses.Add(hostUrl); //Add the new host that request for joining to the host list of this machine
}
//Console.WriteLine("\nNew host has been added : " + hostUrl.getFullUrl());
return(listAllHostsExcept(hostUrl));
//note: if the add procedure be successful, then the list of all hosts except local host will be send,
//if there were no host more than local host it will return an empty String same as "" but not null
}
catch (System.Exception)
{ //because of setUrlHost & set port
//Console.WriteLine("Joining a new host has crached, maybe entered URL or port has a problem.");
//Console.WriteLine(e.Message);
return(null);//if the joining process fail in any cases, this null value will show this failure
}
}
public override void controlPanel()
{
if (ServerStatus.getServerStatus()) //If the server is in its ready state!
{
Console.WriteLine("\n");
Console.WriteLine("___________________________________________");
Console.WriteLine("HPN Calendar Tools Options [Online Mode]: ");
Console.WriteLine(" 1-SignOff This Host");
Console.WriteLine(" 2-List All Hosts");
Console.WriteLine(" 3-List All Appointments");
Console.WriteLine(" 4-Create An Appointment");
Console.WriteLine(" 5-Remove An Appointment");
Console.WriteLine(" 6-Modify An Appointment");
Console.WriteLine(" 7-Disply An Appointment");
Console.WriteLine(" 8-Exit");
Console.WriteLine("___________________________________________");
Console.Write(">>Input the number of intended command :> ");
this.executeUserCommands(true);
}
else
{
Console.WriteLine("\n");
Console.WriteLine("_______________________________________________");
Console.WriteLine("This host is offline, sign On for more options.");
Console.WriteLine("You can just see last appointments that has");
Console.WriteLine("been saved on hard disk in last connection.");
Console.WriteLine("");
Console.WriteLine("HPN Calendar Tools Options[Offline Mode]: ");
Console.WriteLine(" 1-SignOn/Connect To The Network");
Console.WriteLine(" 2-List All Appointments");
Console.WriteLine(" 3-Show An Appointment ");
Console.WriteLine(" 4-Exit");
Console.WriteLine("___________________________________________");
Console.Write(">>Input the number of intended command :> ");
this.executeUserCommands(false);
}
}
//@Override
public bool addNewAppointment(int seqNumberInt, String dateTimeString, int secDurationInt, String header, String comment)
{
//call by other clients to send a new appointment
//because in C# XmlRpcServer Library stoping the servicing has an error we refuse the incoming requests if the server
//is not in its online mode.
if (!ServerStatus.getServerStatus())
{
return(false);
}
Integer seqNumber;
Date dateTime;
Integer secDuration;
try
{
seqNumber = new Integer(seqNumberInt);
dateTime = new Date(dateTimeString);
secDuration = new Integer(secDurationInt);
}
catch (System.Exception)
{
//Console.WriteLine("\nOne request for adding a new appointment to the current system has received but in converting the data in has crashed by the following exception : ");
//Console.WriteLine("Exception Message : \n" + e.Message);
//Console.WriteLine("Received Data : " + "\nSeqential Number : " + seqNumberInt + "\nDate : " + dateTimeString + "\nDuration " + secDurationInt + "\nHeader" + header + "\nComment" + comment);
return(false);
}
if (seqNumber.intValue() < 1)
{
//because it will called by remote host throwing exception is meaning less.
//throw new System.ArgumentOutOfRangeException("The sequential number[seqNumber] must be greater than 0.");
//Console.WriteLine("\nOne request for adding a new appointment to the current system has received but the sequential number was invalid.");
//Console.WriteLine("Received Data : " + "\nSeqential Number : " + seqNumberInt + "\nDate : " + dateTimeString + "\nDuration " + secDurationInt + "\nHeader" + header + "\nComment" + comment);
return(false);
}
else if (secDuration.intValue() < 1)
{
//throw new System.ArgumentOutOfRangeException("The seconds of duration[secDuration] must be greater than 0.");
//Console.WriteLine("\nOne request for adding a new appointment to the current system has received but the duration number was invalid.");
//Console.WriteLine("Received Data : " + "\nSeqential Number : " + seqNumberInt + "\nDate : " + dateTimeString + "\nDuration " + secDurationInt + "\nHeader" + header + "\nComment" + comment);
return(false);
}
//Create requested sequence number or a new sequence number and add the appointment to the array list.
try
{
//We make the sequential number and then check for its existance
//if the sequential number is exist then we make a new one and it will continue till get a unique sequential number
//another strategy for here can be to return false if we have the current sequential number in this host
//but we think it is better to not lose any apointment even with registering it with a wrong sequential number
//but based on what said in the assignment sheet
//we must not consider the conflict of the concurrency of the creation of appointments
SequentialNumber sqn = new SequentialNumber(seqNumber.intValue());
bool flag;
do
{
flag = false;
foreach (Appointment tempAppointment in this.appointmentsList) //search to sure about non existence of the new sequence number in appointment list
{
if (tempAppointment.getSequentialNumber() == sqn.getSequentialNumber())
{
sqn = new SequentialNumber();
flag = true;
break;
}
}
}while(flag);
if (sqn.getSequentialNumber() != seqNumber.intValue())
{
Console.WriteLine("Remote addAppointment: The sequance number [" + seqNumber.intValue() + "] that has been sent by a remote host, is exist. So a new sequance number has assigned : " + sqn.getSequentialNumber());
}
Appointment appointment = new Appointment(sqn, dateTime, secDuration.intValue(), header, comment);
this.appointmentsList.Add(appointment);
if (this.appointmentsList.Exists(temp => temp == appointment)) //if the add was successful?
{
//This will show when a far host add an appointment to the list
//Console.WriteLine("");
//Console.WriteLine("_______________________________");
//Console.WriteLine("One appointment has been added.");
//Console.WriteLine("-------------------------------");
//Console.WriteLine(appointment.ToString());
this.setLastModified();
this.updateLocalDatabase();
return(true);
}
else
{
return(false);
}
}
catch (System.IndexOutOfRangeException) //for creating sequential number
{
//Console.WriteLine(e.Message);
return(false);
}
}
//this will call by others
//@Override
public String requestModifyPermission(String requesterId, int requesterLogicalClock, int requestedAppointmentSequentialNumber, String requesterHostUrl, int requesterHostPort)
{
//the clock will manage here too
//this will call by others to send [req<id,clock>] to this host
//By receiving a req message we will send a true that mean we receive your message
//if we want to accept the request at time we will send a OK instead
//we must implement this pseudocode
// *********************************************
// if (not accessing resource and do not want to access it)
// send OK
// else if (currently using resource)
// queue request
// else if (want to access resource too)
// if (timestamp of request is smaller)
// send OK
// else //own timestamp is smaller
// queue request
// *********************************************
try{
if (!ServerStatus.getServerStatus())
{
return(null);
}
long id = Convert.ToInt64(requesterId);
HostUrl hostUrl = new HostUrl(requesterHostUrl, requesterHostPort);
RequestObject requestObject = new RequestObject(id, requesterLogicalClock, hostUrl); //the clock for receiving message will correct here
//the clock will correct in the constructor of ExternalLampartClock class based on following rule
//LC = Max(LC, LCsender) + 1
String response = null;
//if not accessing resource and do not want to access it --> send OK
if (currentModifyRequest == null ||
(currentModifyRequest != null &&
requestedAppointmentSeqNum != 0 &&
requestedAppointmentSeqNum != requestedAppointmentSequentialNumber)
)
{
ExtendedLamportClockObject ELC = new ExtendedLamportClockObject(); //for increasing clock before send
response = "true" + "\n"; //Send 'OK'
response += " ID:&@[" + ELC.getIdString() + "]#! ";
response += " LC:&@[" + ELC.getLogicalClock() + "]#! ";
return(response);
} //if currently using resource
else if (currentModifyRequest != null &&
!currentModifyRequest.isWaiting() &&
requestedAppointmentSeqNum != 0 &&
requestedAppointmentSeqNum == requestedAppointmentSequentialNumber
)
{
modifyRequestsQueue.add(requestObject);
response = "false" + "\n"; //Send 'NOKEY'//means 'you have to wait for me'
return(response);
} //if want to access resource too
else if (currentModifyRequest != null &&
currentModifyRequest.isWaiting() &&
requestedAppointmentSeqNum != 0 &&
requestedAppointmentSeqNum == requestedAppointmentSequentialNumber
)
{
if (requestObject.getELCO().compare(currentModifyRequest.getELCO()) < 0) //if timestamp of requester is smaller
{
ExtendedLamportClockObject ELC = new ExtendedLamportClockObject(); //for increasing clock before send
response = "true" + "\n"; //Send 'OK'
response += " ID:&@[" + ELC.getIdString() + "]#! ";
response += " LC:&@[" + ELC.getLogicalClock() + "]#! ";
return(response);
}
else //if own timestamp is smaller
{
modifyRequestsQueue.add(requestObject);
response = "false" + "\n"; //Send 'OK'//means 'you have to wait for me'
return(response);
}
}
else
{
return(null);
}
}catch (Exception) { return(null); }
}