Update OOP/Java/Assignments/FISAC/Q10.java

OOP/Java/Assignments/FISAC/Q10.java

@@ -1,5 +1,3 @@
-import java.util.concurrent.locks.*;
-
 class FullException extends Exception {
     FullException(String msg) { super(msg); }
 }
@@ -7,31 +5,19 @@ class FullException extends Exception {
 class Box<T> {
     private T[] items = (T[]) new Object[3];
     private int count = 0;
-    private Lock lock = new ReentrantLock();
-    private Condition notFull = lock.newCondition(), notEmpty = lock.newCondition();
 
-    void add(T item) throws FullException, InterruptedException {
-        lock.lock();
-        try {
-            if (count == items.length) throw new FullException("Box is full");
-            while (count == items.length) notFull.await();
-            items[count++] = item;
-            notEmpty.signal();
-        } finally {
-            lock.unlock();
-        }
+    synchronized void add(T item) throws FullException, InterruptedException {
+        if (count == items.length) throw new FullException("Box is full");
+        while (count == items.length) wait();
+        items[count++] = item;
+        notifyAll();
     }
 
-    T retrieve() throws InterruptedException {
-        lock.lock();
-        try {
-            while (count == 0) notEmpty.await();
-            T item = items[--count];
-            notFull.signal();
-            return item;
-        } finally {
-            lock.unlock();
-        }
+    synchronized T retrieve() throws InterruptedException {
+        while (count == 0) wait();
+        T item = items[--count];
+        notifyAll();
+        return item;
     }
 
     boolean isEmpty() {