static void Main(string[] args) { Customer y = new Customer("Tan Ah Kow", "20, Seaside Road", "XXX20", new DateTime(1989, 10, 11)); Customer z = new Customer("Kim Lee Keng", "2, Rich View", "XXX9F", new DateTime(1993, 4, 25)); BankAccount2 a = new BankAccount2("001-001-001", y, 2000); BankAccount2 b = new BankAccount2("001-001-002", z, 5000); Console.WriteLine(a.Show()); Console.WriteLine(b.Show()); a.Deposit(100); Console.WriteLine(a.Show()); a.Withdraw(200); Console.WriteLine(a.Show()); a.TransferTo(300, b); Console.WriteLine(a.Show()); Console.WriteLine(b.Show()); }
static void Main(string[] args) { var tasks0 = new List <Task>(); var ba0 = new BankAccount2(); for (int i = 0; i < 10; ++i) { tasks0.Add(Task.Factory.StartNew(() => { for (int j = 0; j < 1000; ++j) { ba0.Deposit(100); } })); tasks0.Add(Task.Factory.StartNew(() => { for (int j = 0; j < 1000; ++j) { ba0.Withdraw(100); } })); } Task.WaitAll(tasks0.ToArray()); Console.WriteLine($"Final balance is {ba0.Balance}."); // show interlocked methods here // Interlocked.MemoryBarrier is a wrapper for Thread.MemoryBarrier // only required on memory systems that have weak memory ordering (e.g., Itanium) // prevents the CPU from reordering the instructions such that those before the barrier // execute after those after Console.WriteLine("All done here."); Console.WriteLine(); #region Mutex var tasks = new List <Task>(); var ba = new BankAccount3(0); var ba2 = new BankAccount3(0); // many synchro types deriving from WaitHandle // Mutex = mutual exclusion // two types of mutexes // this is a _local_ mutex Mutex mutex = new Mutex(); Mutex mutex2 = new Mutex(); for (int i = 0; i < 10; ++i) { tasks.Add(Task.Factory.StartNew(() => { for (int j = 0; j < 1000; ++j) { bool haveLock = mutex.WaitOne(); try { ba.Deposit(1); // deposit 10000 overall } finally { if (haveLock) { mutex.ReleaseMutex(); } } } })); tasks.Add(Task.Factory.StartNew(() => { for (int j = 0; j < 1000; ++j) { bool haveLock = mutex2.WaitOne(); try { ba2.Deposit(1); // deposit 10000 } finally { if (haveLock) { mutex2.ReleaseMutex(); } } } })); // transfer needs to lock both accounts tasks.Add(Task.Factory.StartNew(() => { for (int j = 0; j < 1000; j++) { bool haveLock = Mutex.WaitAll(new[] { mutex, mutex2 }); try { ba.Transfer(ba2, 1); // transfer 10k from ba to ba2 } finally { if (haveLock) { mutex.ReleaseMutex(); mutex2.ReleaseMutex(); } } } })); } Task.WaitAll(tasks.ToArray()); Console.WriteLine($"Final balance is: ba={ba.Balance}, ba2={ba2.Balance}."); #endregion }