Java tutorial
/* * Copyright 2013 Netflix, Inc. * * 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 com.netflix.suro.sink.notice; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; import com.netflix.servo.annotations.DataSourceType; import com.netflix.servo.annotations.Monitor; import com.netflix.servo.monitor.Monitors; import com.netflix.suro.TagKey; import com.netflix.util.Pair; import java.util.concurrent.BlockingQueue; import java.util.concurrent.LinkedBlockingQueue; import java.util.concurrent.TimeUnit; import java.util.concurrent.atomic.AtomicLong; /** * Memory based implementation of {@link com.netflix.suro.sink.notice.Notice} * * @param <E> type of notice * * @author jbae */ public class QueueNotice<E> implements Notice<E> { public static final String TYPE = "queue"; private static final int DEFAULT_LENGTH = 100; private static final long DEFAULT_TIMEOUT = 1000; private final BlockingQueue<E> queue; private final long timeout; @Monitor(name = TagKey.SENT_COUNT, type = DataSourceType.COUNTER) private AtomicLong sentMessageCount = new AtomicLong(0); @Monitor(name = TagKey.RECV_COUNT, type = DataSourceType.COUNTER) private AtomicLong recvMessageCount = new AtomicLong(0); @Monitor(name = TagKey.LOST_COUNT, type = DataSourceType.COUNTER) private AtomicLong lostMessageCount = new AtomicLong(0); public QueueNotice() { queue = new LinkedBlockingQueue<E>(DEFAULT_LENGTH); timeout = DEFAULT_TIMEOUT; Monitors.registerObject(this); } @JsonCreator public QueueNotice(@JsonProperty("length") int length, @JsonProperty("recvTimeout") long timeout) { this.queue = new LinkedBlockingQueue<E>(length > 0 ? length : DEFAULT_LENGTH); this.timeout = timeout > 0 ? timeout : DEFAULT_TIMEOUT; } @Override public void init() { } @Override public boolean send(E message) { if (queue.offer(message)) { sentMessageCount.incrementAndGet(); return true; } else { lostMessageCount.incrementAndGet(); return false; } } @Override public E recv() { try { return queue.poll(timeout, TimeUnit.MILLISECONDS); } catch (InterruptedException e) { return null; } } @Override public Pair<String, E> peek() { return new Pair<String, E>("", queue.peek()); } @Override public void remove(String key) { } @Override public String getStat() { return String.format("QueueNotice with the size: %d, sent : %d, received: %d, dropped: %d", queue.size(), sentMessageCount.get(), recvMessageCount.get(), lostMessageCount.get()); } }