| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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.apache.tomcat.websocket.server; |
| |
| import java.util.Comparator; |
| import java.util.Iterator; |
| import java.util.Set; |
| import java.util.concurrent.ConcurrentSkipListSet; |
| import java.util.concurrent.atomic.AtomicInteger; |
| |
| import org.apache.tomcat.websocket.BackgroundProcess; |
| import org.apache.tomcat.websocket.BackgroundProcessManager; |
| |
| /** |
| * Provides timeouts for asynchronous web socket writes. On the server side we |
| * only have access to {@link javax.servlet.ServletOutputStream} and |
| * {@link javax.servlet.ServletInputStream} so there is no way to set a timeout |
| * for writes to the client. |
| */ |
| public class WsWriteTimeout implements BackgroundProcess { |
| |
| private final Set<WsRemoteEndpointImplServer> endpoints = |
| new ConcurrentSkipListSet<>(new EndpointComparator()); |
| private final AtomicInteger count = new AtomicInteger(0); |
| private int backgroundProcessCount = 0; |
| private volatile int processPeriod = 1; |
| |
| @Override |
| public void backgroundProcess() { |
| // This method gets called once a second. |
| backgroundProcessCount ++; |
| |
| if (backgroundProcessCount >= processPeriod) { |
| backgroundProcessCount = 0; |
| |
| long now = System.currentTimeMillis(); |
| Iterator<WsRemoteEndpointImplServer> iter = endpoints.iterator(); |
| while (iter.hasNext()) { |
| WsRemoteEndpointImplServer endpoint = iter.next(); |
| if (endpoint.getTimeoutExpiry() < now) { |
| // Background thread, not the thread that triggered the |
| // write so no need to use a dispatch |
| endpoint.onTimeout(false); |
| } else { |
| // Endpoints are ordered by timeout expiry so if this point |
| // is reached there is no need to check the remaining |
| // endpoints |
| break; |
| } |
| } |
| } |
| } |
| |
| |
| @Override |
| public void setProcessPeriod(int period) { |
| this.processPeriod = period; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| * |
| * The default value is 1 which means asynchronous write timeouts are |
| * processed every 1 second. |
| */ |
| @Override |
| public int getProcessPeriod() { |
| return processPeriod; |
| } |
| |
| |
| public void register(WsRemoteEndpointImplServer endpoint) { |
| boolean result = endpoints.add(endpoint); |
| if (result) { |
| int newCount = count.incrementAndGet(); |
| if (newCount == 1) { |
| BackgroundProcessManager.getInstance().register(this); |
| } |
| } |
| } |
| |
| |
| public void unregister(WsRemoteEndpointImplServer endpoint) { |
| boolean result = endpoints.remove(endpoint); |
| if (result) { |
| int newCount = count.decrementAndGet(); |
| if (newCount == 0) { |
| BackgroundProcessManager.getInstance().unregister(this); |
| } |
| } |
| } |
| |
| |
| /** |
| * Note: this comparator imposes orderings that are inconsistent with equals |
| */ |
| private static class EndpointComparator implements |
| Comparator<WsRemoteEndpointImplServer> { |
| |
| @Override |
| public int compare(WsRemoteEndpointImplServer o1, |
| WsRemoteEndpointImplServer o2) { |
| |
| long t1 = o1.getTimeoutExpiry(); |
| long t2 = o2.getTimeoutExpiry(); |
| |
| if (t1 < t2) { |
| return -1; |
| } else if (t1 == t2) { |
| return 0; |
| } else { |
| return 1; |
| } |
| } |
| } |
| } |