Mercurial > hg > blitz_condensed
view src/com/go/trove/net/DistributedSocketFactory.java @ 34:6f68e94c1fb8 default tip
Add CondensedStats monitoring utility, equivalent to vmstat
author | Dominic Cleal <dominic-cleal@cdo2.com> |
---|---|
date | Thu, 05 Aug 2010 11:07:25 +0100 |
parents | 3dc0c5604566 |
children |
line wrap: on
line source
/* ==================================================================== * Trove - Copyright (c) 1997-2000 Walt Disney Internet Group * ==================================================================== * The Tea Software License, Version 1.1 * * Copyright (c) 2000 Walt Disney Internet Group. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. The end-user documentation included with the redistribution, * if any, must include the following acknowledgment: * "This product includes software developed by the * Walt Disney Internet Group (http://opensource.go.com/)." * Alternately, this acknowledgment may appear in the software itself, * if and wherever such third-party acknowledgments normally appear. * * 4. The names "Tea", "TeaServlet", "Kettle", "Trove" and "BeanDoc" must * not be used to endorse or promote products derived from this * software without prior written permission. For written * permission, please contact opensource@dig.com. * * 5. Products derived from this software may not be called "Tea", * "TeaServlet", "Kettle" or "Trove", nor may "Tea", "TeaServlet", * "Kettle", "Trove" or "BeanDoc" appear in their name, without prior * written permission of the Walt Disney Internet Group. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE WALT DISNEY INTERNET GROUP OR ITS * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * ==================================================================== * * For more information about Tea, please see http://opensource.go.com/. */ package com.go.trove.net; import java.io.*; import java.net.*; import java.util.*; import java.lang.ref.*; import com.go.trove.util.IdentityMap; /****************************************************************************** * A SocketFactory implementation for distributing load among several * SocketFactories. If an exception occurs on a socket, its pool is put into * the "dead" list. A special thread will run in the background, trying to * resurrect the dead SocketSocket. As soon as its able to create sockets * again, its added back into the "live" list. * <p> * Consider wrapping with a {@link LazySocketFactory} for automatic checking * against socket factories that may be dead. * * @author Brian S O'Neill * @version * <!--$$Revision: 1.1 $-->, <!--$$JustDate:--> 01/01/22 <!-- $--> */ public class DistributedSocketFactory implements SocketFactory { private final long mTimeout; private int mFactoryIndex; // Contains only the live SocketFactories. private List mFactories; // Maps SocketPools to resurrector threads. private Map mResurrectors; // Maps CheckedSockets to the SocketPools that they came from. private Map mSocketSources; private CheckedSocket.ExceptionListener mListener; /** * @param timeout Maximum time to wait (in milliseconds) for new * connections to be established before throwing an exception */ public DistributedSocketFactory(long timeout) { mTimeout = timeout; mFactories = Collections.synchronizedList(new ArrayList()); mResurrectors = Collections.synchronizedMap(new HashMap()); mSocketSources = Collections.synchronizedMap(new IdentityMap()); mListener = new CheckedSocket.ExceptionListener() { public void exceptionOccurred(CheckedSocket s, Exception e, int count) { if (count == 1) { deadFactory((SocketFactory)mSocketSources.get(s)); } } }; } public void addSocketFactory(SocketFactory factory) { mFactories.add(factory); } public void removeSocketFactory(SocketFactory factory) { mFactories.remove(factory); Thread t = (Thread)mResurrectors.remove(factory); if (t != null) { t.interrupt(); } } public InetAddressAndPort getInetAddressAndPort() { try { return getFactory(selectFactory(null)).getInetAddressAndPort(); } catch (ConnectException e) { return InetAddressAndPort.UNKNOWN; } } public InetAddressAndPort getInetAddressAndPort(Object session) { try { return getFactory(selectFactory(session)) .getInetAddressAndPort(session); } catch (ConnectException e) { return InetAddressAndPort.UNKNOWN; } } public long getDefaultTimeout() { return mTimeout; } public CheckedSocket createSocket() throws ConnectException, SocketException { return createSocket(null, mTimeout); } public CheckedSocket createSocket(Object session) throws ConnectException, SocketException { return createSocket(session, mTimeout); } public CheckedSocket createSocket(long timeout) throws ConnectException, SocketException { return createSocket(null, timeout); } public CheckedSocket createSocket(Object session, long timeout) throws ConnectException, SocketException { long startTime = timeout > 0 ? System.currentTimeMillis() : 0; int index = selectFactory(session); int count = mFactories.size(); for (int i=0; i<count; i++) { SocketFactory factory = null; try { factory = getFactory(index++); CheckedSocket socket = factory.createSocket(session, timeout); socket.addExceptionListener(mListener); mSocketSources.put(socket, factory); return socket; } catch (SocketException e) { deadFactory(factory); if (timeout == 0) { throw e; } if (timeout > 0) { timeout -= (System.currentTimeMillis() - startTime); if (timeout < 0) { throw e; } } } } throw new ConnectException("Unable to create socket"); } public CheckedSocket getSocket() throws ConnectException, SocketException { return getSocket(null, mTimeout); } public CheckedSocket getSocket(Object session) throws ConnectException, SocketException { return getSocket(session, mTimeout); } public CheckedSocket getSocket(long timeout) throws ConnectException, SocketException { return getSocket(null, timeout); } public CheckedSocket getSocket(Object session, long timeout) throws ConnectException, SocketException { long startTime = timeout > 0 ? System.currentTimeMillis() : 0; int index = selectFactory(session); int count = mFactories.size(); for (int i=0; i<count; i++) { SocketFactory factory = null; try { factory = getFactory(index++); CheckedSocket socket = factory.getSocket(session, timeout); socket.addExceptionListener(mListener); mSocketSources.put(socket, factory); return socket; } catch (SocketException e) { deadFactory(factory); if (timeout == 0) { throw e; } if (timeout > 0) { timeout -= (System.currentTimeMillis() - startTime); if (timeout < 0) { throw e; } } } } throw new ConnectException("Unable to get socket"); } public void recycleSocket(CheckedSocket socket) throws SocketException, IllegalArgumentException { if (socket == null) { return; } SocketFactory source = (SocketFactory)mSocketSources.remove(socket); if (source == null) { throw new IllegalArgumentException ("Socket did not originate from this pool"); } socket.removeExceptionListener(mListener); source.recycleSocket(socket); } public void clear() { synchronized (mFactories) { for (int i = mFactories.size(); --i >= 0; ) { ((SocketFactory)mFactories.get(i)).clear(); } } } public int getAvailableCount() { int count = 0; synchronized (mFactories) { for (int i = mFactories.size(); --i >= 0; ) { count += ((SocketFactory)mFactories.get(i)) .getAvailableCount(); } } return count; } /** * The provided index must be positive, but it can be out of the factory * list bounds. */ private SocketFactory getFactory(int index) throws ConnectException { synchronized (mFactories) { int size = mFactories.size(); if (size <= 0) { throw new ConnectException("No SocketFactories available"); } return (SocketFactory)mFactories.get(index % size); } } /** * Returns an index which is positive, but may be out of the factory list * bounds. */ private int selectFactory(Object session) throws ConnectException { if (session != null) { return session.hashCode() & 0x7fffffff; } else { synchronized (mFactories) { return mFactoryIndex++ & 0x7fffffff; } } } private void deadFactory(SocketFactory factory) { if (factory == null) { return; } synchronized (mFactories) { // Only remove factory if its not the last one left. if (mFactories.contains(factory) && mFactories.size() > 1) { mFactories.remove(factory); Resurrector r = new Resurrector(this, factory); Thread t = new Thread(null, r, "Resurrector " + factory.getInetAddressAndPort()); t.setDaemon(true); t.start(); mResurrectors.put(factory, t); } } } private static class Resurrector implements Runnable { // Weakly references owner so that this thread won't prevent it from // being garbage collected. private final Reference mOwner; private final SocketFactory mFactory; public Resurrector(DistributedSocketFactory owner, SocketFactory factory) { mOwner = new WeakReference(owner); mFactory = factory; } public void run() { DistributedSocketFactory owner = null; try { while (!Thread.interrupted()) { owner = (DistributedSocketFactory)mOwner.get(); if (owner == null) { break; } try { mFactory.recycleSocket(mFactory.createSocket()); owner.mFactories.add(mFactory); break; } catch (IOException e) { } owner = null; // Wait at 5 seconds before trying again. try { Thread.sleep(5000); } catch (InterruptedException e) { break; } } } finally { owner = (DistributedSocketFactory)mOwner.get(); if (owner != null) { owner.mResurrectors.remove(mFactory); } } } } }