| /** |
| * 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.activemq.transport.nio; |
| |
| import java.io.IOException; |
| import java.nio.channels.SelectionKey; |
| import java.nio.channels.Selector; |
| import java.util.Iterator; |
| import java.util.Set; |
| import java.util.concurrent.ConcurrentLinkedQueue; |
| import java.util.concurrent.atomic.AtomicInteger; |
| |
| public class SelectorWorker implements Runnable { |
| |
| private static final AtomicInteger NEXT_ID = new AtomicInteger(); |
| |
| final SelectorManager manager; |
| final Selector selector; |
| final int id = NEXT_ID.getAndIncrement(); |
| private final int maxChannelsPerWorker; |
| |
| final AtomicInteger retainCounter = new AtomicInteger(1); |
| private final ConcurrentLinkedQueue<Runnable> ioTasks = new ConcurrentLinkedQueue<Runnable>(); |
| |
| public SelectorWorker(SelectorManager manager) throws IOException { |
| this.manager = manager; |
| selector = Selector.open(); |
| maxChannelsPerWorker = manager.getMaxChannelsPerWorker(); |
| manager.getSelectorExecutor().execute(this); |
| } |
| |
| void retain() { |
| if (retainCounter.incrementAndGet() == maxChannelsPerWorker) { |
| manager.onWorkerFullEvent(this); |
| } |
| } |
| |
| void release() { |
| int use = retainCounter.decrementAndGet(); |
| if (use == 0) { |
| manager.onWorkerEmptyEvent(this); |
| } else if (use == maxChannelsPerWorker - 1) { |
| manager.onWorkerNotFullEvent(this); |
| } |
| } |
| |
| boolean isReleased() { |
| return retainCounter.get()==0; |
| } |
| |
| |
| public void addIoTask(Runnable work) { |
| ioTasks.add(work); |
| selector.wakeup(); |
| } |
| |
| private void processIoTasks() { |
| Runnable task; |
| while( (task= ioTasks.poll()) !=null ) { |
| try { |
| task.run(); |
| } catch (Throwable e) { |
| e.printStackTrace(); |
| } |
| } |
| } |
| |
| |
| |
| public void run() { |
| |
| String origName = Thread.currentThread().getName(); |
| try { |
| Thread.currentThread().setName("Selector Worker: " + id); |
| while (!isReleased()) { |
| |
| processIoTasks(); |
| |
| int count = selector.select(10); |
| |
| if (count == 0) { |
| continue; |
| } |
| |
| // Get a java.util.Set containing the SelectionKey objects |
| // for all channels that are ready for I/O. |
| Set keys = selector.selectedKeys(); |
| |
| for (Iterator i = keys.iterator(); i.hasNext();) { |
| final SelectionKey key = (SelectionKey)i.next(); |
| i.remove(); |
| |
| final SelectorSelection s = (SelectorSelection)key.attachment(); |
| try { |
| if( key.isValid() ) { |
| key.interestOps(0); |
| } |
| |
| // Kick off another thread to find newly selected keys |
| // while we process the |
| // currently selected keys |
| manager.getChannelExecutor().execute(new Runnable() { |
| public void run() { |
| try { |
| s.onSelect(); |
| s.enable(); |
| } catch (Throwable e) { |
| s.onError(e); |
| } |
| } |
| }); |
| |
| } catch (Throwable e) { |
| s.onError(e); |
| } |
| |
| } |
| |
| } |
| } catch (Throwable e) { |
| e.printStackTrace(); |
| // Notify all the selections that the error occurred. |
| Set keys = selector.keys(); |
| for (Iterator i = keys.iterator(); i.hasNext();) { |
| SelectionKey key = (SelectionKey)i.next(); |
| SelectorSelection s = (SelectorSelection)key.attachment(); |
| s.onError(e); |
| } |
| } finally { |
| try { |
| manager.onWorkerEmptyEvent(this); |
| selector.close(); |
| } catch (IOException ignore) { |
| ignore.printStackTrace(); |
| } |
| Thread.currentThread().setName(origName); |
| } |
| } |
| |
| } |