Return-Path: Delivered-To: apmail-ws-commons-dev-archive@minotaur.apache.org Received: (qmail 67619 invoked from network); 10 May 2009 12:07:18 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.3) by minotaur.apache.org with SMTP; 10 May 2009 12:07:18 -0000 Received: (qmail 55698 invoked by uid 500); 10 May 2009 12:07:18 -0000 Delivered-To: apmail-ws-commons-dev-archive@ws.apache.org Received: (qmail 55616 invoked by uid 500); 10 May 2009 12:07:18 -0000 Mailing-List: contact commons-dev-help@ws.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: commons-dev@ws.apache.org Delivered-To: mailing list commons-dev@ws.apache.org Received: (qmail 55606 invoked by uid 99); 10 May 2009 12:07:17 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Sun, 10 May 2009 12:07:17 +0000 X-ASF-Spam-Status: No, hits=-2000.0 required=10.0 tests=ALL_TRUSTED X-Spam-Check-By: apache.org Received: from [140.211.11.4] (HELO eris.apache.org) (140.211.11.4) by apache.org (qpsmtpd/0.29) with ESMTP; Sun, 10 May 2009 12:07:15 +0000 Received: by eris.apache.org (Postfix, from userid 65534) id 2142F23888F4; Sun, 10 May 2009 12:06:55 +0000 (UTC) Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: svn commit: r773328 - in /webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base: ./ tracker/ Date: Sun, 10 May 2009 12:06:54 -0000 To: commons-dev@ws.apache.org From: veithen@apache.org X-Mailer: svnmailer-1.0.8 Message-Id: <20090510120655.2142F23888F4@eris.apache.org> X-Virus-Checked: Checked by ClamAV on apache.org Author: veithen Date: Sun May 10 12:06:54 2009 New Revision: 773328 URL: http://svn.apache.org/viewvc?rev=773328&view=rev Log: WSCOMMONS-466: Implemented a more robust mechanism to track Axis services in AbstractTransportListener. Added: webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/ webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceFilter.java (with props) webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceTracker.java (with props) webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceTrackerListener.java (with props) webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/package-info.java (with props) Modified: webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/AbstractTransportListener.java Modified: webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/AbstractTransportListener.java URL: http://svn.apache.org/viewvc/webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/AbstractTransportListener.java?rev=773328&r1=773327&r2=773328&view=diff ============================================================================== --- webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/AbstractTransportListener.java (original) +++ webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/AbstractTransportListener.java Sun May 10 12:06:54 2009 @@ -26,16 +26,15 @@ import org.apache.axis2.util.MessageContextBuilder; import org.apache.axis2.transport.base.threads.WorkerPool; import org.apache.axis2.transport.base.threads.WorkerPoolFactory; +import org.apache.axis2.transport.base.tracker.AxisServiceFilter; +import org.apache.axis2.transport.base.tracker.AxisServiceTracker; +import org.apache.axis2.transport.base.tracker.AxisServiceTrackerListener; import org.apache.axis2.transport.TransportListener; import org.apache.axis2.engine.AxisEngine; -import org.apache.axis2.engine.AxisObserver; -import org.apache.axis2.engine.AxisConfiguration; -import org.apache.axis2.engine.AxisEvent; import org.apache.axis2.addressing.EndpointReference; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.axiom.om.util.UUIDGenerator; -import org.apache.axiom.om.OMElement; import javax.management.MBeanServer; import javax.management.ObjectName; @@ -58,8 +57,10 @@ protected int state = BaseConstants.STOPPED; /** is this transport non-blocking? */ protected boolean isNonBlocking = false; - /** the axis observer that gets notified of service life cycle events*/ - private final AxisObserver axisObserver = new GenericAxisObserver(); + /** + * Service tracker used to invoke {@link #internalStartListeningForService(AxisService)} + * and {@link #internalStopListeningForService(AxisService)}. */ + private AxisServiceTracker serviceTracker; /** the thread pool to execute actual poll invocations */ protected WorkerPool workerPool = null; @@ -101,7 +102,23 @@ } // register to receive updates on services for lifetime management - cfgCtx.getAxisConfiguration().addObservers(axisObserver); + serviceTracker = new AxisServiceTracker( + cfgCtx.getAxisConfiguration(), + new AxisServiceFilter() { + public boolean matches(AxisService service) { + return !service.getName().startsWith("__") // these are "private" services + && BaseUtils.isUsingTransport(service, getTransportName()); + } + }, + new AxisServiceTrackerListener() { + public void serviceAdded(AxisService service) { + internalStartListeningForService(service); + } + + public void serviceRemoved(AxisService service) { + internalStopListeningForService(service); + } + }); // register with JMX mbeanSupport = new TransportMBeanSupport(this, getTransportName()); @@ -132,11 +149,8 @@ if (state == BaseConstants.STARTED) { state = BaseConstants.STOPPED; // cancel receipt of service lifecycle events - cfgCtx.getAxisConfiguration().getObserversList().remove(axisObserver); log.info(getTransportName().toUpperCase() + " Listener Shutdown"); - for (AxisService service : getListeningServices()) { - internalStopListeningForService(service); - } + serviceTracker.stop(); } } @@ -147,31 +161,10 @@ // cfgCtx.getAxisConfiguration().addObservers(axisObserver); log.info(getTransportName().toUpperCase() + " Listener started"); // iterate through deployed services and start - for (AxisService service : getListeningServices()) { - internalStartListeningForService(service); - } + serviceTracker.start(); } } - /** - * Get the list of services that are listening on this transport, i.e. that are - * configured to use this transport. - * - * @return the list of listening services - */ - private List getListeningServices() { - List result = new LinkedList(); - Iterator services = cfgCtx.getAxisConfiguration().getServices().values().iterator(); - while (services.hasNext()) { - AxisService service = (AxisService) services.next(); - if (!ignoreService(service) - && BaseUtils.isUsingTransport(service, getTransportName())) { - result.add(service); - } - } - return result; - } - public EndpointReference[] getEPRsForService(String serviceName, String ip) throws AxisFault { return getEPRsForService(serviceName); } @@ -180,10 +173,6 @@ return null; } - private boolean ignoreService(AxisService service) { - return service.getName().startsWith("__"); // these are "private" services - } - public void disableTransportForService(AxisService service) { log.warn("Disabling the " + getTransportName() + " transport for the service " @@ -204,7 +193,7 @@ } } - private void internalStartListeningForService(AxisService service) { + void internalStartListeningForService(AxisService service) { String serviceName = service.getName(); try { startListeningForService(service); @@ -237,7 +226,7 @@ getEndpointMBeanName(serviceName)); } - private void internalStopListeningForService(AxisService service) { + void internalStopListeningForService(AxisService service) { unregisterMBean(getEndpointMBeanName(service.getName())); stopListeningForService(service); } @@ -352,47 +341,6 @@ return metrics; } - /** - * An AxisObserver which will start listening for newly deployed or started services, - * and stop listening when services are undeployed or stopped. - */ - class GenericAxisObserver implements AxisObserver { - - // The initilization code will go here - public void init(AxisConfiguration axisConfig) { - } - - public void serviceUpdate(AxisEvent event, AxisService service) { - - if (!ignoreService(service) - && BaseUtils.isUsingTransport(service, getTransportName())) { - switch (event.getEventType()) { - case AxisEvent.SERVICE_DEPLOY : - internalStartListeningForService(service); - break; - case AxisEvent.SERVICE_REMOVE : - internalStopListeningForService(service); - break; - case AxisEvent.SERVICE_START : - internalStartListeningForService(service); - break; - case AxisEvent.SERVICE_STOP : - internalStopListeningForService(service); - break; - } - } - } - - public void moduleUpdate(AxisEvent event, AxisModule module) {} - public void addParameter(Parameter param) throws AxisFault {} - public void removeParameter(Parameter param) throws AxisFault {} - public void deserializeParameters(OMElement parameterElement) throws AxisFault {} - public Parameter getParameter(String name) { return null; } - public ArrayList getParameters() { return null; } - public boolean isParameterLocked(String parameterName) { return false; } - public void serviceGroupUpdate(AxisEvent event, AxisServiceGroup serviceGroup) {} - } - // -- jmx/management methods-- /** * Pause the listener - Stop accepting/processing new messages, but continues processing existing Added: webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceFilter.java URL: http://svn.apache.org/viewvc/webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceFilter.java?rev=773328&view=auto ============================================================================== --- webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceFilter.java (added) +++ webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceFilter.java Sun May 10 12:06:54 2009 @@ -0,0 +1,36 @@ +/* + * 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.axis2.transport.base.tracker; + +import org.apache.axis2.description.AxisService; + +/** + * Filter for {@link AxisService} instances. This interface is used by + * {@link AxisServiceTracker}. + */ +public interface AxisServiceFilter { + /** + * Examine whether a given service matches the filter criteria. + * + * @param service the service to examine + * @return true if the service matches the filter criteria + */ + boolean matches(AxisService service); +} Propchange: webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceFilter.java ------------------------------------------------------------------------------ svn:eol-style = native Added: webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceTracker.java URL: http://svn.apache.org/viewvc/webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceTracker.java?rev=773328&view=auto ============================================================================== --- webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceTracker.java (added) +++ webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceTracker.java Sun May 10 12:06:54 2009 @@ -0,0 +1,244 @@ +/* + * 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.axis2.transport.base.tracker; + +import java.util.ArrayList; +import java.util.HashSet; +import java.util.LinkedList; +import java.util.Queue; +import java.util.Set; + +import org.apache.axiom.om.OMElement; +import org.apache.axis2.AxisFault; +import org.apache.axis2.description.AxisModule; +import org.apache.axis2.description.AxisService; +import org.apache.axis2.description.AxisServiceGroup; +import org.apache.axis2.description.Parameter; +import org.apache.axis2.engine.AxisConfiguration; +import org.apache.axis2.engine.AxisEvent; +import org.apache.axis2.engine.AxisObserver; + +/** + *

Tracks services deployed in a given {@link AxisConfiguration}. + * The tracker is configured with references to three objects:

+ *
    + *
  1. An {@link AxisConfiguration} to watch.
    2. + *
  2. An {@link AxisServiceFilter} restricting the services to track.
    3. + *
  3. An {@link AxisServiceTrackerListener} receiving tracking events.
    4. + *
+ *

An instance of this class maintains an up-to-date list of services + * satisfying all of the following criteria:

+ *
    + *
  1. The service is deployed in the given {@link AxisConfiguration}.
    2. + *
  2. The service is started, i.e. {@link AxisService#isActive()} returns true.
    3. + *
  3. The service matches the criteria specified by the given + * {@link AxisServiceFilter} instance.
    4. + *
+ *

Whenever a service appears on the list, the tracker will call + * {@link AxisServiceTrackerListener#serviceAdded(AxisService)}. When a service disappears, it + * will call {@link AxisServiceTrackerListener#serviceRemoved(AxisService)}.

+ *

When the tracker is created, it is initially in the stopped state. In this state no + * events will be sent to the listener. It can be started using {@link #start()} and stopped again + * using {@link #stop()}. The tracker list is defined to be empty when the tracker is in the + * stopped state. This implies that a call to {@link #start()} will generate + * {@link AxisServiceTrackerListener#serviceAdded(AxisService)} events for all services that meet + * the above criteria at that point in time. In the same way, {@link #stop()} will generate + * {@link AxisServiceTrackerListener#serviceRemoved(AxisService)} events for the current entries + * in the list.

+ *

As a corollary the tracker guarantees that during a complete lifecycle (start-stop), + * there will be exactly one {@link AxisServiceTrackerListener#serviceRemoved(AxisService)} event + * for every {@link AxisServiceTrackerListener#serviceAdded(AxisService)} event and vice-versa. + * This property is important when the tracker is used to allocate resources for a dynamic set + * of services.

+ * + *

Limitations

+ * + *

The tracker is not able to detect property changes on services. E.g. if a service initially + * matches the filter criteria, but later changes so that it doesn't match the criteria any more, + * the tracker will not be able to detect this and the service will not be removed from the tracker + * list.

+ */ +public class AxisServiceTracker { + private final AxisObserver observer = new AxisObserver() { + public void init(AxisConfiguration axisConfig) {} + + public void serviceUpdate(AxisEvent event, final AxisService service) { + switch (event.getEventType()) { + case AxisEvent.SERVICE_DEPLOY: + case AxisEvent.SERVICE_START: + if (filter.matches(service)) { + boolean pending; + synchronized (lock) { + if (pending = (pendingActions != null)) { + pendingActions.add(new Runnable() { + public void run() { + serviceAdded(service); + } + }); + } + } + if (!pending) { + serviceAdded(service); + } + } + break; + case AxisEvent.SERVICE_REMOVE: + case AxisEvent.SERVICE_STOP: + // Don't check filter here because the properties of the service may have + // changed in the meantime. + boolean pending; + synchronized (lock) { + if (pending = (pendingActions != null)) { + pendingActions.add(new Runnable() { + public void run() { + serviceRemoved(service); + } + }); + } + } + if (!pending) { + serviceRemoved(service); + } + } + } + + public void moduleUpdate(AxisEvent event, AxisModule module) {} + public void addParameter(Parameter param) throws AxisFault {} + public void removeParameter(Parameter param) throws AxisFault {} + public void deserializeParameters(OMElement parameterElement) throws AxisFault {} + public Parameter getParameter(String name) { return null; } + public ArrayList getParameters() { return null; } + public boolean isParameterLocked(String parameterName) { return false; } + public void serviceGroupUpdate(AxisEvent event, AxisServiceGroup serviceGroup) {} + }; + + private final AxisConfiguration config; + final AxisServiceFilter filter; + private final AxisServiceTrackerListener listener; + + /** + * Object used to synchronize access to {@link #pendingActions} and {@link #services}. + */ + final Object lock = new Object(); + + /** + * Queue for notifications received by the {@link AxisObserver} during startup of the tracker. + * We need this because the events may already be reflected in the list of services returned + * by {@link AxisConfiguration#getServices()} (getting the list of currently deployed services + * and adding the observer can't be done atomically). It also allows us to make sure that + * events are sent to the listener in the right order, e.g. when a service is being removed + * during startup of the tracker. + */ + Queue pendingActions; + + /** + * The current list of services. null if the tracker is stopped. + */ + private Set services; + + public AxisServiceTracker(AxisConfiguration config, AxisServiceFilter filter, + AxisServiceTrackerListener listener) { + this.config = config; + this.filter = filter; + this.listener = listener; + } + + /** + * Check whether the tracker is started. + * + * @return true if the tracker is started + */ + public boolean isStarted() { + return services != null; + } + + /** + * Start the tracker. + * + * @throws IllegalStateException if the tracker has already been started + */ + public void start() { + if (services != null) { + throw new IllegalStateException(); + } + synchronized (lock) { + pendingActions = new LinkedList(); + config.addObservers(observer); + services = new HashSet(); + } + for (AxisService service : config.getServices().values()) { + if (service.isActive() && filter.matches(service)) { + serviceAdded(service); + } + } + while (true) { + Runnable action; + synchronized (lock) { + action = pendingActions.poll(); + if (action == null) { + pendingActions = null; + break; + } + } + action.run(); + } + } + + void serviceAdded(AxisService service) { + // callListener may be false because the observer got an event for a service that + // was already in the initial list of services retrieved by AxisConfiguration#getServices. + boolean callListener; + synchronized (lock) { + callListener = services.add(service); + } + if (callListener) { + listener.serviceAdded(service); + } + } + + void serviceRemoved(AxisService service) { + // callListener may be false because the observer invokes this method without applying the + // filter. + boolean callListener; + synchronized (lock) { + callListener = services.remove(service); + } + if (callListener) { + listener.serviceRemoved(service); + } + } + + /** + * Stop the tracker. + * + * @throws IllegalStateException if the tracker is not started + */ + public void stop() { + if (services == null) { + throw new IllegalStateException(); + } + // TODO: This is very bad, but AxisConfiguration has no removeObserver method! + config.getObserversList().remove(observer); + for (AxisService service : services) { + listener.serviceRemoved(service); + } + services = null; + } +} Propchange: webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceTracker.java ------------------------------------------------------------------------------ svn:eol-style = native Added: webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceTrackerListener.java URL: http://svn.apache.org/viewvc/webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceTrackerListener.java?rev=773328&view=auto ============================================================================== --- webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceTrackerListener.java (added) +++ webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceTrackerListener.java Sun May 10 12:06:54 2009 @@ -0,0 +1,41 @@ +/* + * 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.axis2.transport.base.tracker; + +import org.apache.axis2.description.AxisService; + +/** + * Listener for events generated by an {@link AxisServiceTracker}. + */ +public interface AxisServiceTrackerListener { + /** + * Inform the listener that a service has been added to tracker list. + * + * @param service the service that has been added to the tracker list + */ + void serviceAdded(AxisService service); + + /** + * Inform the listener that a service has been removed from the tracker list. + * + * @param service the service that has been removed from the tracker list + */ + void serviceRemoved(AxisService service); +} Propchange: webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/AxisServiceTrackerListener.java ------------------------------------------------------------------------------ svn:eol-style = native Added: webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/package-info.java URL: http://svn.apache.org/viewvc/webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/package-info.java?rev=773328&view=auto ============================================================================== --- webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/package-info.java (added) +++ webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/package-info.java Sun May 10 12:06:54 2009 @@ -0,0 +1,26 @@ +/* + * 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. + */ + +/** + * Contains utility classes to track a dynamic set of services deployed in an + * Axis configuration. + * + * @see org.apache.axis2.transport.base.tracker.AxisServiceTracker + */ +package org.apache.axis2.transport.base.tracker; \ No newline at end of file Propchange: webservices/commons/trunk/modules/transport/modules/base/src/main/java/org/apache/axis2/transport/base/tracker/package-info.java ------------------------------------------------------------------------------ svn:eol-style = native