Java tutorial
/* * Copyright 2016 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.gradle.launcher.daemon.server.health.gc; import com.google.common.collect.Sets; import java.util.Set; import java.util.concurrent.LinkedBlockingDeque; import java.util.concurrent.locks.ReentrantLock; public class DefaultSlidingWindow<T> implements SlidingWindow<T> { final LinkedBlockingDeque<T> deque; final ReentrantLock lock = new ReentrantLock(); public DefaultSlidingWindow(int capacity) { this.deque = new LinkedBlockingDeque<T>(capacity); } @Override public void slideAndInsert(T element) { lock.lock(); try { while (!deque.offerLast(element)) { deque.remove(); } } finally { lock.unlock(); } } @Override public Set<T> snapshot() { lock.lock(); try { return Sets.newLinkedHashSet(deque); } finally { lock.unlock(); } } }