static void Main(string[] args)
{
// create the array of bank accounts
BankAccount[] accounts = new BankAccount[5];
for (int i = 0; i < accounts.Length; i++) {
accounts[i] = new BankAccount();
}
// create the total balance counter
int totalBalance = 0;
// create the barrier
Barrier barrier = new Barrier(5, (myBarrier) => {
// zero the balance
totalBalance = 0;
// sum the account totals
foreach (BankAccount account in accounts) {
totalBalance += account.Balance;
}
// write out the balance
Console.WriteLine("Total balance: {0}", totalBalance);
});
// define the tasks array
Task[] tasks = new Task[5];
// loop to create the tasks
for (int i = 0; i < tasks.Length; i++) {
tasks[i] = new Task((stateObj) => {
// create a typed reference to the account
BankAccount account = (BankAccount)stateObj;
// start of phase
Random rnd = new Random();
for (int j = 0; j < 1000; j++) {
account.Balance += rnd.Next(1, 100);
}
// end of phase
// tell the user that this task has has completed the phase
Console.WriteLine("Task {0}, phase {1} ended",
Task.CurrentId, barrier.CurrentPhaseNumber);
// signal the barrier
barrier.SignalAndWait();
// start of phase
// alter the balance of this Task's account using the total balance
// deduct 10% of the difference from the total balance
account.Balance -= (totalBalance - account.Balance) / 10;
// end of phase
// tell the user that this task has has completed the phase
Console.WriteLine("Task {0}, phase {1} ended",
Task.CurrentId, barrier.CurrentPhaseNumber);
// signal the barrier
barrier.SignalAndWait();
},
accounts[i]);
}
// start the task
foreach (Task t in tasks) {
t.Start();
}
// wait for all of the tasks to complete
Task.WaitAll(tasks);
// wait for input before exiting
Console.WriteLine("Press enter to finish");
Console.ReadLine();
}
static void Main(string[] args) {
// create the bank account instances
BankAccount account1 = new BankAccount();
BankAccount account2 = new BankAccount();
// create the mutexes
Mutex mutex1 = new Mutex();
Mutex mutex2 = new Mutex();
// create a new task to update the first account
Task task1 = new Task(() => {
// enter a loop for 1000 balance updates
for (int j = 0; j < 1000; j++) {
// acquire the lock for the account
bool lockAcquired = mutex1.WaitOne();
try {
// update the balance
account1.Balance++;
} finally {
if (lockAcquired) mutex1.ReleaseMutex();
}
}
});
// create a new task to update the first account
Task task2 = new Task(() => {
// enter a loop for 1000 balance updates
for (int j = 0; j < 1000; j++) {
// acquire the lock for the account
bool lockAcquired = mutex2.WaitOne(); ;
try {
// update the balance
account2.Balance += 2;
} finally {
if (lockAcquired) mutex2.ReleaseMutex();
}
}
});
// create a new task to update the first account
Task task3 = new Task(() => {
// enter a loop for 1000 balance updates
for (int j = 0; j < 1000; j++) {
// acquire the locks for both accounts
bool lockAcquired = Mutex.WaitAll(new WaitHandle[] { mutex1, mutex2 });
try {
// simulate a transfer between accounts
account1.Balance++;
account2.Balance--;
} finally {
if (lockAcquired) {
mutex1.ReleaseMutex();
mutex2.ReleaseMutex();
}
}
}
});
// start the tasks
task1.Start();
task2.Start();
task3.Start();
// wait for the tasks to complete
Task.WaitAll(task1, task2, task3);
// write out the counter value
Console.WriteLine("Account1 balance {0}, Account2 balance: {1}",
account1.Balance, account2.Balance);
// wait for input before exiting
Console.WriteLine("Press enter to finish");
Console.ReadLine();
}
