/* Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016. All rights reserved. Contact: SYSTAP, LLC DBA Blazegraph 2501 Calvert ST NW #106 Washington, DC 20008 licenses@blazegraph.com This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /* * Created on May 15, 2009 */ package com.bigdata.cache; import java.util.Collection; import java.util.Iterator; import java.util.NoSuchElementException; import java.util.concurrent.ArrayBlockingQueue; import java.util.concurrent.BlockingQueue; import java.util.concurrent.TimeUnit; import java.util.concurrent.locks.ReentrantLock; /** * A {@link BlockingQueue} based on the {@link RingBuffer}. * * @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a> * @version $Id$ * * @deprecated This implementation is incomplete. Realizing this implementation * would require adding support for signals when the buffer becomes * "nonEmpty" and when it becomes "notFull". However, the * {@link ArrayBlockingQueue} already provides a well-testing ring * buffer which implements the {@link BlockingQueue} API. The only * reason to pursue this implementation further would be to gain * more control over the backing array. For example, so as to be * able to combine chunks together when the generic type of the * array is itself an array type. */ public class BlockingRingBuffer<E> implements BlockingQueue<E> { private final RingBuffer<E> buffer; private final ReentrantLock lock = new ReentrantLock(); /** * @param capacity */ public BlockingRingBuffer(final int capacity) { buffer = new RingBuffer<E>(capacity); } public boolean add(E e) { lock.lock(); try { return buffer.add(e); } finally { lock.unlock(); } } public final int capacity() { return buffer.capacity(); } public void clear() { lock.lock(); try { buffer.clear(); } finally { lock.unlock(); } } public boolean contains(Object ref) { lock.lock(); try { return buffer.contains(ref); } finally { lock.unlock(); } } public boolean containsAll(Collection<?> c) { lock.lock(); try { return buffer.containsAll(c); } finally { lock.unlock(); } } public E element() throws NoSuchElementException { lock.lock(); try { return buffer.element(); } finally { lock.unlock(); } } public final E get(int index) { lock.lock(); try { return buffer.get(index); } finally { lock.unlock(); } } public final boolean isEmpty() { lock.lock(); try { return buffer.isEmpty(); } finally { lock.unlock(); } } public final boolean isFull() { lock.lock(); try { return buffer.isFull(); } finally { lock.unlock(); } } public boolean offer(E ref) { lock.lock(); try { return buffer.offer(ref); } finally { lock.unlock(); } } public final E peek() { lock.lock(); try { return buffer.peek(); } finally { lock.unlock(); } } public E poll() { lock.lock(); try { return buffer.poll(); } finally { lock.unlock(); } } public E remove() throws NoSuchElementException { lock.lock(); try { return buffer.remove(); } finally { lock.unlock(); } } public boolean remove(Object ref) { lock.lock(); try { return buffer.remove(ref); } finally { lock.unlock(); } } public final int size() { lock.lock(); try { return buffer.size(); } finally { lock.unlock(); } } public Object[] toArray() { lock.lock(); try { return buffer.toArray(); } finally { lock.unlock(); } } public <TX> TX[] toArray(TX[] a) { lock.lock(); try { return buffer.toArray(a); } finally { lock.unlock(); } } /** * The lock is not held across the entire operation to avoid the possibility * of deadlock if the queue becomes full. */ public boolean addAll(Collection<? extends E> c) { boolean modified = false; for (E e : c) { add(e); modified = true; } return modified; } public boolean removeAll(Collection<?> c) { lock.lock(); try { return buffer.removeAll(c); } finally { lock.unlock(); } } public boolean retainAll(Collection<?> c) { lock.lock(); try { return buffer.retainAll(c); } finally { lock.unlock(); } } public int drainTo(Collection<? super E> c) { // TODO Auto-generated method stub return 0; } public int drainTo(Collection<? super E> c, int maxElements) { // TODO Auto-generated method stub return 0; } public boolean offer(E e, long timeout, TimeUnit unit) throws InterruptedException { // TODO Auto-generated method stub return false; } public E poll(long timeout, TimeUnit unit) throws InterruptedException { // TODO Auto-generated method stub return null; } // @todo must gain lock and then await signal if buffer is full public void put(E e) throws InterruptedException { // TODO Auto-generated method stub } // @todo must gain lock and then await signal if buffer is empty public E take() throws InterruptedException { // TODO Auto-generated method stub return null; } public int remainingCapacity() { lock.lock(); try { return buffer.capacity() - buffer.size(); } finally { lock.unlock(); } } // public Iterator<E> iterator() { // TODO Auto-generated method stub return null; } }