public DistMutEx(int my_id) {
this.my_id = my_id;
// Reading Config file
try {
rfile = new Scanner(new File("Config.txt"));
while (rfile.hasNextLine()) {
rline = rfile.nextLine();
if (rline.charAt(0) != '#') {
// Skipping the first line of input, Which has only the
// count of the nodes
if (valcn == 0) {
num_nodes = Character.getNumericValue(rline.charAt(0));
valcn = 1;
rline = rfile.nextLine();
}
String[] params = rline.split(" ");
Node temp = new Node(params[0], params[1], params[2]);
temp.print();
nodes.put(params[0], temp);
}
}
// Initializing the Token object
token = new Token(num_nodes);
// Initializing the RN array
RN = new int[DistMutEx.nodes.size()];
// Initializing RN
for (int i = 0; i < DistMutEx.nodes.size(); i++) {
RN[i] = -1;
}
// IF the node id is 0, Hold the token for initial
if (my_id == 0) {
hastoken = true;
}
// Starting MutEx thread to accept requests
p = Integer.parseInt(nodes.get(Integer.toString(my_id)).port);
mutexRecvReqThread = new MutexReqRec(p);
mutexRecvReqThread.start();
rfile.close();
} catch (IOException e) {
rfile.close();
e.printStackTrace();
}
}
public void csLeave() {
tokenInUse = false;
if (requestMade) {
token.LN[my_id] = RN[my_id];
requestMade = false;
}
// Checking if the queue is not empty
if (hastoken && !token.getQueue().isEmpty()) {
MutexReqRec.sendToken();
tokenRecvd = false;
hastoken = false;
Request request = token.getQueue().poll();
// Updating the LN, ie., LN[id] = RN[id]
// Sending the Token to the next Request in the queue
try {
Node node = nodes.get(Integer.toString(request.getId()));
System.out.println("Sending token from cs to " + node.getHostname());
Socket client = new Socket(node.getHostname(), Integer.parseInt(node.getPort()));
OutputStream os = client.getOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(os);
oos.writeObject(token);
oos.close();
os.close();
client.close();
// token = null;
// requestMade = false;
// tokenInUse = false;
} catch (IOException e) {
e.printStackTrace();
}
// tokenInUse = false;
}
}
public boolean csEnter() {
if (hastoken && token.queue.isEmpty()) {
tokenInUse = true;
return hastoken;
} else {
if (hastoken && !token.queue.isEmpty()) {
MutexReqRec.sendToken();
}
if (!exit) {
// Generate CS request
requestMade = true;
counter++;
// Increment RN of my_id********
DistMutEx.RN[my_id]++;
// Generating a new request
Request request = new Request(my_id, counter);
// Broadcast request message to all nodes
for (String node : nodes.keySet()) {
try {
if (!nodes.get(node).id.equals(Integer.toString(my_id))) {
String hostname = nodes.get(node).hostname;
int port = Integer.parseInt(nodes.get(node).port);
System.out.println("request to " + hostname + " port: " + port);
Thread.sleep(100);
Socket client = new Socket(hostname, port);
OutputStream os = client.getOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(os);
oos.writeObject(request);
oos.close();
os.close();
client.close();
}
} catch (IOException e) {
// e.printStackTrace();
} catch (InterruptedException e) {
// e.printStackTrace();
}
}
int counter = 0;
while (!tokenRecvd && counter < 25) {
try {
counter++;
Thread.sleep(100);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("waiting for token...");
}
if (tokenRecvd) {
System.out.println("Token recieved");
tokenInUse = true;
return tokenRecvd;
} else {
System.out.println("Request operation timed out: retrying with new cs request");
DistMutEx.RN[my_id]--;
return false;
}
} else {
System.out.println("Nodes requested for termination");
return false;
}
}
// wait until Token is recvd
}
public void close() {
if (mutexRecvReqThread != null) System.out.println("Reached maximum number of executions");
mutexRecvReqThread.closeThread();
// System.out.println("Closing algo thread");
return;
}
