ShahDevarsh
diff --git a/‎Data Structures/ArrayListQueue.java
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+78Lines changed: 78 additions & 0 deletions b/‎Data Structures/ArrayListQueue.java
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+78Lines changed: 78 additions & 0 deletions
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+import java.util.ArrayList;
+
+/**
+ * This class represents the concept of a classical, theoretical Queue. It supports the two basic operations,
+ * Enqueue and Dequeue, as well, as isEmpty and size.
+ *
+ * @param <T> Being a generic class, one can choose which type to fill the queue with.
+ */
+public class ArrayListQueue<T> {
+
+    private final ArrayList<T> queue;
+    private final int capacity;
+
+    ArrayListQueue(int capacity) {
+        this.queue = new ArrayList<T>(capacity);
+        this.capacity = capacity;
+    }
+
+    public void enqueue(T element) {
+        if (this.queue.size() == this.capacity) {
+            System.err.println("Queue is full");
+
+            return;
+        }
+
+        this.queue.add(element);
+    }
+
+    public T dequeue() {
+        if (this.queue.isEmpty()) {
+            System.err.println("Queue is empty");
+
+            return null;
+        }
+
+        T element = this.queue.get(0);
+        this.queue.remove(0);
+
+        return element;
+    }
+
+    public boolean isEmpty() {
+        return this.queue.isEmpty();
+    }
+
+    public int size() {
+        return this.queue.size();
+    }
+}
+
+class ArrayListQueueExample {
+    public static void main(String[] args) {
+        ArrayListQueue<Integer> intQueue = new ArrayListQueue<Integer>(10);
+
+        //Fills queue to capacity
+        for(int i = 0; i < 10; i++) {
+            intQueue.enqueue(i);
+        }
+
+        //Should print an error
+        intQueue.enqueue(-1);
+
+        //Flushes the queue completely
+        for(int i = 0; i < 10; i++) {
+            int element = intQueue.dequeue();
+
+            System.out.println(element);
+        }
+
+        //Should print an error and return null
+        if (intQueue.dequeue() == null) {
+            //Should be true
+            System.out.println(intQueue.isEmpty());
+        }
+
+
+    }
+}