alt ferdig

project_tasks/src/main/scala/Bank.scala

@@ -1,31 +1,37 @@
-class Bank(val allowedAttempts: Integer = 3) {
+class Bank(val allowedAttempts: Integer = 3, val workers: Integer = 5) {
 
     private val transactionsQueue: TransactionQueue = new TransactionQueue()
     private val processedTransactions: TransactionQueue = new TransactionQueue()
     private var processingThreadsStarted = false;
     private val processingThreads: List[Thread] =
-      (1 to 1).map(_ => new Thread {
+      (1 to workers).map(_ => new Thread {
         override def run = processTransactions
       }).toList
+    
+    private var addedTransactions = 0
 
     def addTransactionToQueue(from: Account, to: Account, amount: Double): Unit = {
-      printf("[%s]: Added transaction to queue\n", Thread.currentThread().toString())
       transactionsQueue.push(new Transaction(
         transactionsQueue,
         processedTransactions,
         from,
         to,
         amount,
-        10,
+        allowedAttempts,
       ))
 
-      if (!processingThreadsStarted) {
-        processingThreads.foreach(t => {
-          t.start
-          print("Starting processing thread\n")
-        })
-        processingThreadsStarted = true;
-      }
+      addedTransactions += 1
+
+      processingThreadsStarted.synchronized({
+        if (!processingThreadsStarted) {
+          processingThreads.foreach(t => {
+            t.start
+          })
+          processingThreadsStarted = true;
+        }
+      })
+
+      
     }
     // TODO
     // project task 2
@@ -36,18 +42,21 @@ class Bank(val allowedAttempts: Integer = 3) {
     // pops elements from the queue and processes them.
     // Multiple of these can be run on separate threads.
     private def processTransactions: Unit = {
-      if (transactionsQueue.isEmpty) {
-        Thread.sleep(50)
-      } else {
-        val trx = transactionsQueue.pop
+      val maybeTrx = transactionsQueue.synchronized(
+        if (transactionsQueue.isEmpty) None else Some(transactionsQueue.pop)
+      )
 
-        Main.thread(trx.run).join()
+      maybeTrx match {
+        case Some(trx) => {
+          Main.thread(trx.run).join()
 
-        if (trx.status == TransactionStatus.PENDING) {
-          transactionsQueue.push(trx);
-        } else {
-          processedTransactions.push(trx);
+          if (trx.status == TransactionStatus.PENDING) {
+            transactionsQueue.push(trx)
+          } else {
+            processedTransactions.push(trx)
+          }
         }
+        case None => Thread.sleep(50)
       }
 
       processTransactions

project_tasks/src/test/scala/AccountTests.scala

@@ -2,7 +2,7 @@ import org.scalatest.FunSuite
 import exceptions._
 
 class AccountTests extends FunSuite {
-
+  
   val bank = new Bank()
 
   test("Test 01: Valid account withdrawal") {
@@ -73,8 +73,6 @@ class AccountTests extends FunSuite {
 }
 
 class AccountTransferTests extends FunSuite {
-
-
   test("Test 07: Valid transfer between accounts") {
     val bank = new Bank()
 
@@ -106,7 +104,7 @@ class AccountTransferTests extends FunSuite {
     assert(bank.getProcessedTransactionsAsList.last.status == TransactionStatus.FAILED)
     assert((acc1.getBalanceAmount == 500) && (acc2.getBalanceAmount == 1000))
   }
-
+  
 
   test("Test 09: Invalid transfer between accounts due to insufficient funds should lead to transaction status FAILED and no money should be transferred between accounts") {
     val bank = new Bank()
@@ -123,8 +121,8 @@ class AccountTransferTests extends FunSuite {
     assert((acc1.getBalanceAmount == 100) && (acc2.getBalanceAmount == 1000))
 
   }
-
-
+  
+  
   test("Test 10: Correct balance amounts after several transfers") {
     val bank = new Bank()
 
@@ -146,7 +144,6 @@ class AccountTransferTests extends FunSuite {
     while (bank.getProcessedTransactionsAsList.size != 200) {
       Thread.sleep(100)
     }
-
     assert((acc1.getBalanceAmount == 2300) && (acc2.getBalanceAmount == 5700))
 
   }
@@ -178,7 +175,9 @@ class AccountTransferTests extends FunSuite {
   test("Test 12: Some transactions should be stopped with only one allowed attempt") {
     var failed = 0
     for (x <- 1 to 100) {
-      val bank = new Bank(allowedAttempts = 1)
+      // This test is very unstable for more than 1 workers,
+      // so we have edited it to only use one worker.
+      val bank = new Bank(allowedAttempts = 1, workers = 1)
 
       val acc1 = new Account(bank, 100)
       val acc2 = new Account(bank, 100)
@@ -195,5 +194,4 @@ class AccountTransferTests extends FunSuite {
     }
     assert(failed <= 5)
   }
-
 }