commit Exercise_30_08

csv77 · csv77 · commit b12b886cd52c · 2017-09-30T19:00:16.000+02:00
diff --git a/Chapter_30/exercise_30_08/Exercise_30_08.java b/Chapter_30/exercise_30_08/Exercise_30_08.java
@@ -0,0 +1,73 @@
+package exercise_30_08;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.locks.Condition;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+
+public class Exercise_30_08 {
+    private static Account account = new Account();
+
+    public static void main(String[] args) {
+        ExecutorService executor = Executors.newFixedThreadPool(2);
+        executor.execute(new DepositTask());
+        executor.execute(new WithdrawTask());
+        executor.shutdown();
+
+        System.out.println("Thread 1\t\tThread 2\t\tBalance");
+    }
+
+    public static class DepositTask implements Runnable {
+        @Override
+        public void run() {
+            try {
+                while(true) {
+                    account.deposit((int)(Math.random() * 10) + 1);
+                    Thread.sleep(1000);
+                }
+            }
+            catch (InterruptedException ex) {
+                ex.printStackTrace();
+            }
+        }
+    }
+
+    public static class WithdrawTask implements Runnable {
+        @Override
+        public void run() {
+            while(true) {
+                account.withdraw((int)(Math.random() * 10) + 1);
+            }
+        }
+    }
+
+    private static class Account {
+        private int balance = 0;
+
+        public int getBalance() {
+            return balance;
+        }
+
+        public synchronized void withdraw(int amount) {
+            try {
+                while(balance < amount) {
+                    System.out.println("\t\t\tWait for a deposit");
+                    wait();
+                }
+                balance -= amount;
+                System.out.println("\t\t\tWithdraw " + amount + "\t\t" + getBalance());
+            }
+            catch (InterruptedException ex) {
+                ex.printStackTrace();
+            }
+        }
+
+        public synchronized void deposit(int amount) {
+            balance += amount;
+            System.out.println("Deposit " + amount + "\t\t\t\t\t" + getBalance());
+
+            notifyAll();
+        }
+    }
+}
