我将使用T数组，首尾指针以及add和get方法。
像：（错误查找留给用户）
// Hijack these for simplicityimport java.nio.BufferOverflowException;import java.nio.BufferUnderflowException;public class CircularBuffer<T> { private T[] buffer; private int tail; private int head; @SuppressWarnings("unchecked") public CircularBuffer(int n) { buffer = (T[]) new Object[n]; tail = 0; head = 0; } public void add(T toAdd) { if (head != (tail - 1)) { buffer[head++] = toAdd; } else { throw new BufferOverflowException(); } head = head % buffer.length; } public T get() { T t = null; int adjTail = tail > head ? tail - buffer.length : tail; if (adjTail < head) { t = (T) buffer[tail++]; tail = tail % buffer.length; } else { throw new BufferUnderflowException(); } return t; } public String toString() { return "CircularBuffer(size=" + buffer.length + ", head=" + head + ", tail=" + tail + ")"; } public static void main(String[] args) { CircularBuffer<String> b = new CircularBuffer<String>(3); for (int i = 0; i < 10; i++) { System.out.println("Start: " + b); b.add("One"); System.out.println("One: " + b); b.add("Two"); System.out.println("Two: " + b); System.out.println("Got '" + b.get() + "', now " + b); b.add("Three"); System.out.println("Three: " + b); // Test Overflow // b.add("Four"); // System.out.println("Four: " + b); System.out.println("Got '" + b.get() + "', now " + b); System.out.println("Got '" + b.get() + "', now " + b); // Test Underflow // System.out.println("Got '" + b.get() + "', now " + b); // Back to start, let's shift on one b.add("Foo"); b.get(); } }}
