update,

_resources/it114105/itp4510/Lab03/Lab3.3/ArrayQueue.java

@@ -0,0 +1,59 @@
+public class ArrayQueue {
+    public static final int CAPACITY = 1000;
+    private int capacity;
+    private Object[] array;
+    private int front = 0;
+    private int rear = 0;
+
+    public ArrayQueue() {
+        this(CAPACITY);
+    }
+
+    public ArrayQueue(int cap) {
+        capacity = cap;
+        array = new Object[capacity];
+    }
+
+    public int size() {
+        return (capacity - front + rear) % capacity;
+    }
+
+    public boolean isEmpty() {
+        return (front == rear);
+    }
+
+    public void enqueue(Object item) throws QueueFullException {
+        if (size() == capacity - 1) {
+            throw new QueueFullException();
+        }
+        array[rear] = item;
+        rear = (rear + 1) % capacity;
+    }
+
+    public Object dequeue() throws QueueEmptyException {
+        if (isEmpty()) {
+            throw new QueueEmptyException();
+        }
+        Object item = array[front];
+        array[front] = null;
+        front = (front + 1) % capacity;
+        return item;
+    }
+
+    public Object front() throws QueueEmptyException {
+        if (isEmpty()) {
+            throw new QueueEmptyException();
+        }
+        return array[front];
+    }
+
+    public String toString() {
+        String s = "[ ";
+        int next = front;
+        for (int i = 0; i < size(); i++) {
+            s += array[next] + " ";
+            next = front + i;
+        }
+        return s + " ]";
+    }
+}