circular buffer implementation

data-structures/src/main/java/com/baeldung/circularbuffer/CircularBuffer.java

@@ -0,0 +1,73 @@
+package com.baeldung.circularbuffer;
+
+public class CircularBuffer<E> {
+
+    private int capacity, writeIndex, readIndex;
+    private E[] data;
+
+    @SuppressWarnings("unchecked")
+    public CircularBuffer(int capacity) {
+
+        this.capacity = capacity;
+        this.data = (E[]) new Object[capacity];
+
+        this.readIndex = 0;
+        this.writeIndex = -1;
+    }
+
+    public boolean offer(E element) {
+
+        if (!isFull()) {
+
+            writeIndex += 1;
+            int nextWriteIndex = writeIndex % capacity;
+            data[nextWriteIndex] = element;
+
+            return true;
+        }
+
+        return false;
+    }
+
+    public E poll() {
+
+        if (!isEmpty()) {
+
+            int nextReadIndex = readIndex % capacity;
+            readIndex += 1;
+
+            return data[nextReadIndex];
+        }
+
+        return null;
+    }
+
+    public E peek() {
+
+        if (!isEmpty()) {
+
+            return data[readIndex % capacity];
+        }
+
+        return null;
+    }
+
+    public int capacity() {
+        return capacity;
+    }
+
+    public int size() {
+
+        return (writeIndex - readIndex) + 1;
+    }
+
+    public boolean isEmpty() {
+
+        return writeIndex < readIndex;
+    }
+
+    public boolean isFull() {
+
+        return size() >= capacity;
+    }
+}