plugins/org.eclipse.wst.server.core/servercore/org/eclipse/wst/server/core/model/ServerBehaviourDelegate.java

/**********************************************************************
 * Copyright (c) 2005 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - Initial API and implementation
 **********************************************************************/
package org.eclipse.wst.server.core.model;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.eclipse.core.runtime.*;
import org.eclipse.debug.core.ILaunchConfigurationWorkingCopy;
import org.eclipse.osgi.util.NLS;
import org.eclipse.wst.server.core.IModule;
import org.eclipse.wst.server.core.IServer;
import org.eclipse.wst.server.core.internal.Messages;
import org.eclipse.wst.server.core.internal.ProgressUtil;
import org.eclipse.wst.server.core.internal.Server;
import org.eclipse.wst.server.core.internal.ServerPlugin;
import org.eclipse.wst.server.core.internal.Trace;
/**
 * A server delegate provides the implementation for various 
 * generic and server-type-specific operations for a specific type of server.
 * A server delegate is specified by the
 * <code>class</code> attribute of a <code>serverTypes</code> extension.
 * <p>
 * When the server instance needs to be given a delegate, the delegate class
 * specified for the server type is instantiated with a 0-argument constructor
 * and primed with <code>delegate.initialize(((IServerState)server)</code>, 
 * which it is expected to hang on to. Later, when
 * <code>delegate.dispose()</code> is called as the server instance is
 * being discarded, the delegate is expected to let go of the server instance.
 * </p>
 * <p>
 * Server delegates may keep state in instance fields, but that state is
 * transient and will not be persisted across workbench sessions.
 * </p>
 * <p>
 * This abstract class is intended to be extended only by clients
 * to extend the <code>serverTypes</code> extension point.
 * </p>
 * 
 * @see org.eclipse.wst.server.core.IServer
 * @see org.eclipse.wst.server.core.IServerWorkingCopy
 * @plannedfor 1.0
 */
public abstract class ServerBehaviourDelegate {
	private Server server;

	/**
	 * Publish kind constant (value 0) for no change.
	 * 
	 * @see #publishModule(int, int, IModule[], IProgressMonitor)
	 */
	public static final int NO_CHANGE = 0;

	/**
	 * Publish kind constant (value 1) for added resources.
	 * 
	 * @see #publishModule(int, int, IModule[], IProgressMonitor)
	 */
	public static final int ADDED = 1;

	/**
	 * Publish kind constant (value 2) for changed resources.
	 * 
	 * @see #publishModule(int, int, IModule[], IProgressMonitor)
	 */
	public static final int CHANGED = 2;

	/**
	 * Publish kind constant (value 3) for removed resources.
	 * 
	 * @see #publishModule(int, int, IModule[], IProgressMonitor)
	 */
	public static final int REMOVED = 3;

	/**
	 * Delegates must have a public 0-arg constructor.
	 */
	public ServerBehaviourDelegate() {
		// do nothing
	}

	/**
	 * Initializes this server delegate with its life-long server instance.
	 * <p>
	 * This method is called by the server core framework.
	 * Clients should never call this method.
	 * </p>
	 * 
	 * @param newServer the server instance
	 * @param monitor a progress monitor, or <code>null</code> if progress
	 *    reporting and cancellation are not desired
	 */
	final void initialize(Server newServer, IProgressMonitor monitor) {
		server = newServer;
		initialize(monitor);
	}

	/**
	 * Initializes this server delegate. This method gives delegates a chance
	 * to do their own initialization.
	 * <p>
	 * If the server state is initially unknown, this method should attempt
	 * to connect to the server and update the state. On servers where the
	 * state may change, this is also an excellent place to create a background
	 * thread that will constantly ping the server (or have a listener) to
	 * update the server state as changes occur.
	 * </p>
	 * <p>
	 * This method is called by the server core framework.
	 * Clients should never call this method.
	 * </p>
	 */
	protected void initialize(IProgressMonitor monitor) {
		// do nothing
	}

	/**
	 * Returns the server that this server delegate corresponds to.
	 * 
	 * @return the server
	 */
	public final IServer getServer() {
		return server;
	}

	/**
	 * Sets the current state of this server.
	 *
	 * @param state the current state of the server, one of the state
	 *    constants defined by {@link IServer}
	 * @see IServer#getServerState()
	 */
	protected final void setServerState(int state) {
		server.setServerState(state);
	}

	/**
	 * Sets the ILaunchManager mode that the server is running in. The server
	 * implementation will automatically return <code>null</code> to clients
	 * when the server is stopped, so you only need to update the mode when
	 * it changes.
	 * 
	 * @param mode the mode in which a server is running, one of the mode constants
	 *    defined by {@link org.eclipse.debug.core.ILaunchManager}
	 */
	protected final void setMode(String mode) {
		server.setMode(mode);
	}

	/**
	 * Sets the server restart state.
	 *
	 * @param state <code>true</code> if the server needs to be restarted,
	 *    and <code>false</code> otherwise
	 */
	protected final void setServerRestartState(boolean state) {
		server.setServerRestartState(state);
	}

	/**
	 * Sets the server publish state.
	 *
	 * @param state the current publish state of the server, one of the
	 *    publish constants defined by {@link IServer}
	 */
	protected final void setServerPublishState(int state) {
		server.setServerPublishState(state);
	}

	/**
	 * Hook to fire an event when a module state changes.
	 * 
	 * @param module the module
	 * @param state the current state of the module, one of the state
	 *    constants defined by {@link IServer}
	 */
	protected final void setModuleState(IModule[] module, int state) {
		server.setModuleState(module, state);
	}

	/**
	 * Sets the module publish state.
	 *
	 * @param module the module
	 * @param state the current publish state of the module, one of the
	 *    publish constants defined by {@link IServer}
	 */
	protected final void setModulePublishState(IModule[] module, int state) {
		server.setModulePublishState(module, state);
	}

	/**
	 * Sets the module restart state.
	 *
	 * @param module the module
	 * @param state <code>true</code> if the module needs to be restarted,
	 *    and <code>false</code> otherwise
	 */
	protected final void setModuleRestartState(IModule[] module, boolean state) {
		server.setModuleRestartState(module, state);
	}

	/**
	 * Disposes of this server delegate.
	 * <p>
	 * This method is called by the web server core framework.
	 * Clients should never call this method.
	 * </p>
	 * <p>
	 * Implementations are expected to let go of the delegate's reference
	 * to the server, deregister listeners, etc.
	 * </p>
	 */
	public void dispose() {
		// do nothing
	}

	/**
	 * Methods called to notify that publishing is about to begin.
	 * This allows the server to open a connection to the server
	 * or get any global information ready.
	 * <p>
	 * This method is called by the server core framework,
	 * in response to a call to <code>IServer.publish()</code>.
	 * Clients should never call this method.
	 * </p>
	 *
	 * @param monitor a progress monitor, or <code>null</code> if progress
	 *    reporting and cancellation are not desired
	 * @throws CoreException if there is a problem starting the publish
	 */
	protected void publishStart(IProgressMonitor monitor) throws CoreException {
		// do nothing
	}

	/**
	 * Publish the server.
	 * <p>
	 * This method is called by the server core framework,
	 * in response to a call to <code>IServer.publish()</code>.
	 * Clients should never call this method.
	 * </p>
	 * 
	 * @param kind one of the IServer.PUBLISH_XX constants. Valid values are
	 *    <ul>
	 *    <li><code>PUBLSIH_FULL</code>- indicates a full publish.</li>
	 *    <li><code>PUBLISH_INCREMENTAL</code>- indicates a incremental publish.
	 *    <li><code>PUBLSIH_AUTO</code>- indicates an automatic incremental publish.</li>
	 *    <li><code>PUBLISH_CLEAN</code>- indicates a clean request. Clean throws
	 *      out all state and cleans up the module on the server before doing a
	 *      full publish.
	 *    </ul>
	 * @param monitor a progress monitor, or <code>null</code> if progress
	 *    reporting and cancellation are not desired
	 * @throws CoreException if there is a problem publishing the server
	 */
	protected void publishServer(int kind, IProgressMonitor monitor) throws CoreException {
		// do nothing
	}

	/**
	 * Publish a single module to the server.
	 * <p>
	 * This method is called by the server core framework,
	 * in response to a call to <code>IServer.publish()</code>.
	 * Clients should never call this method directly.
	 * </p>
	 * <p>
	 * If the deltaKind is IServer.REMOVED, the module may have been completely
	 * deleted and does not exist anymore. In this case, a dummy module (with the
	 * correct id) will be passed to this method.
	 * </p>
	 * 
	 * @param kind one of the IServer.PUBLISH_XX constants. Valid values are:
	 *    <ul>
	 *    <li><code>PUBLSIH_FULL</code>- indicates a full publish.</li>
	 *    <li><code>PUBLISH_INCREMENTAL</code>- indicates a incremental publish.
	 *    <li><code>PUBLSIH_AUTO</code>- indicates an automatic incremental publish.</li>
	 *    <li><code>PUBLISH_CLEAN</code>- indicates a clean request. Clean throws
	 *      out all state and cleans up the module on the server before doing a
	 *      full publish.
	 *    </ul>
	 * @param module the module to publish
	 * @param deltaKind one of the IServer publish change constants. Valid values are:
	 *    <ul>
	 *    <li><code>ADDED</code>- indicates the module has just been added to the server
	 *      and this is the first publish.
	 *    <li><code>NO_CHANGE</code>- indicates that nothing has changed in the module
	 *      since the last publish.</li>
	 *    <li><code>CHANGED</code>- indicates that the module has been changed since
	 *      the last publish. Call <code>getPublishedResourceDelta()</code> for
	 *      details of the change.
	 *    <li><code>REMOVED</code>- indicates the module has been removed and should be
	 *      removed/cleaned up from the server.
	 *    </ul>
	 * @param monitor a progress monitor, or <code>null</code> if progress
	 *    reporting and cancellation are not desired
	 * @throws CoreException if there is a problem publishing the module
	 */
	protected void publishModule(int kind, int deltaKind, IModule[] module, IProgressMonitor monitor) throws CoreException {
		// do nothing
	}

	/**
	 * Methods called to notify that publishing has finished.
	 * The server can close any open connections to the server
	 * and do any cleanup operations.
	 * <p>
	 * This method is called by the server core framework,
	 * in response to a call to <code>IServer.publish()</code>.
	 * Clients should never call this method.
	 * </p>
	 *
	 * @param monitor a progress monitor, or <code>null</code> if progress
	 *    reporting and cancellation are not desired
	 * @throws CoreException if there is a problem stopping the publish
	 */
	protected void publishFinish(IProgressMonitor monitor) throws CoreException {
		// do nothing
	}

	/**
	 * Configure the given launch configuration to start this server. This method is called whenever
	 * the server is started to ensure that the launch configuration is accurate and up to date.
	 * This method should not blindly update the launch configuration in cases where the user has
	 * access to change the launch configuration by hand.
	 * 
	 * @param workingCopy a launch configuration working copy
	 * @param monitor a progress monitor, or <code>null</code> if progress
	 *    reporting and cancellation are not desired
	 * @throws CoreException if there is an error setting up the configuration
	 */
	public void setupLaunchConfiguration(ILaunchConfigurationWorkingCopy workingCopy, IProgressMonitor monitor) throws CoreException {
		// do nothing
	}

	/**
	 * Restart this server. The server should use the server
	 * listener to notify progress. It must use the same debug
	 * flags as was originally passed into the start() method.
	 * 
	 * This method is used if there is a quick/better way to restart
	 * the server. If it throws a CoreException, the normal stop/start
	 * actions will be used.
	 * 
	 * @param launchMode the mode to restart in, one of the mode constants
	 *    defined by {@link org.eclipse.debug.core.ILaunchManager}
	 * @throws CoreException if there was a problem restarting
	 */
	public void restart(String launchMode) throws CoreException {
		 throw new CoreException(new Status(IStatus.ERROR, ServerPlugin.PLUGIN_ID, 0, "Could not restart", null));
	}

	/**
	 * Returns whether the given module can be restarted.
	 * <p>
	 * [issue: It's unclear whether this operations is guaranteed to be fast
	 * or whether it could involve communication with any actual
	 * server. If it is not fast, the method should take a progress
	 * monitor.]
	 * </p>
	 * 
	 * @param module the module
	 * @return <code>true</code> if the given module can be
	 * restarted, and <code>false</code> otherwise 
	 */
	public boolean canControlModule(IModule[] module) {
		return false;
	}
	
	/**
	 * Starts the given module on the server. See the specification of 
	 * {@link IServer#startModule(IModule[], IServer.IOperationListener)}
	 * for further details. 
	 * <p>
	 * The implementation should update the module sync state and fire
	 * an event for the module.
	 * </p>
	 * <p>
	 * This method will throw an exception if the module does not exist on
	 * the server.
	 * </p>
	 * <p>
	 * [issue: Since this method is ascynchronous, is there
	 * any need for the progress monitor?]
	 * </p>
	 * 
	 * @param module the module to be started
	 * @param monitor a progress monitor, or <code>null</code> if progress
	 *    reporting and cancellation are not desired
	 * @exception CoreException if an error occurs while trying to restart the module
	 */
	public void startModule(IModule[] module, IProgressMonitor monitor) throws CoreException {
		// do nothing
	}

	/**
	 * Stops the given module on the server. See the specification of 
	 * {@link IServer#stopModule(IModule[], IServer.IOperationListener)}
	 * for further details. 
	 * <p>
	 * The implementation should update the module sync state and fire
	 * an event for the module.
	 * </p>
	 * <p>
	 * This method will throw an exception if the module does not exist on
	 * the server.
	 * </p>
	 * <p>
	 * [issue: Since this method is ascynchronous, is there
	 * any need for the progress monitor?]
	 * </p>
	 * 
	 * @param module the module to be stopped
	 * @param monitor a progress monitor, or <code>null</code> if progress
	 *    reporting and cancellation are not desired
	 * @exception CoreException if an error occurs while trying to restart the module
	 */
	public void stopModule(IModule[] module, IProgressMonitor monitor) throws CoreException {
		// do nothing
	}

	/**
	 * Shuts down and stops this server. The server should return from this method
	 * quickly and use the server listener to notify shutdown progress.
	 * <p> 
	 * If force is <code>false</code>, it will attempt to stop the server
	 * normally/gracefully. If force is <code>true</code>, then the server
	 * process will be terminated any way that it can.
	 * </p>
	 * <p>
	 * [issue: There is no way to communicate failure to the
	 * client. Given that this operation can go awry, there probably
	 * should be a mechanism that allows failing asynch operations
	 * to be diagnosed.]
	 * </p>
	 * @param force <code>true</code> to kill the server, or <code>false</code>
	 *    to stop normally
	 */
	public abstract void stop(boolean force);

	/**
	 * Returns the module resources that have been published to the server.
	 * 
	 * <p>
	 * If the module has just been added to the server, an empty list will
	 * be returned. If the module has never existed on the server, a CoreException
	 * will be thrown.
	 * </p>
	 * 
	 * @param module the module
	 * @return an array containing the published module resource
	 */
	protected IModuleResource[] getPublishedResources(IModule[] module) {
		return server.getPublishedResources(module);
	}

	/**
	 * Returns the delta of the current module resources that have been
	 * published compared to the current state of the module.
	 *
	 * @param module the module
	 * @return an array containing the publish resource delta
	 */
	protected IModuleResourceDelta[] getPublishedResourceDelta(IModule[] module) {
		return server.getPublishedResourceDelta(module);
	}

	/**
	 * Returns a temporary directory that the requestor can use
	 * throughout it's lifecycle. This is primary to be used by
	 * servers for working directories, server specific
	 * files, etc.
	 * <p>
	 * This method directory will return the same directory on
	 * each use of the workbench. If the directory is not requested
	 * over a period of time, the directory may be deleted and a
	 * new one will be assigned on the next request. For this
	 * reason, a server may want to request the temp directory on
	 * startup if it wants to store files there. In any case, the
	 * server should have a backup plan to refill the directory
	 * in case it has been deleted since last use.</p>
	 *
	 * @return a temporary directory
	 */
	protected IPath getTempDirectory() {
		return server.getTempDirectory();
	}

	/**
	 * Set a global status on the server.
	 *  
	 * @param status the status
	 */
	protected final void setServerStatus(IStatus status) {
		server.setServerStatus(status);
	}

	/**
	 * Set a status on a specific module.
	 * 
	 * @param module the module
	 * @param status the status
	 */
	protected final void setModuleStatus(IModule[] module, IStatus status) {
		server.setModuleStatus(module, status);
	}
	
	public IStatus publish(int kind, IProgressMonitor monitor) {
		Trace.trace(Trace.FINEST, "-->-- Publishing to server: " + toString() + " -->--");
		
		if (getServer().getServerType().hasRuntime() && getServer().getRuntime() == null)
			return new Status(IStatus.ERROR, ServerPlugin.PLUGIN_ID, 0, Messages.errorPublishNoRuntime, null);
		
		final List moduleList = getAllModules();
		final List kindList = new ArrayList();
		
		Iterator iterator = moduleList.iterator();
		while (iterator.hasNext()) {
			IModule[] module = (IModule[]) iterator.next();
			if (hasBeenPublished(module)) {
				if (getPublishedResourceDelta(module).length == 0)
					kindList.add(new Integer(ServerBehaviourDelegate.NO_CHANGE));
				else
					kindList.add(new Integer(ServerBehaviourDelegate.CHANGED));
			} else
				kindList.add(new Integer(ServerBehaviourDelegate.ADDED));
		}
		
		addRemovedModules(moduleList, kindList);
		
		while (moduleList.size() > kindList.size()) {
			kindList.add(new Integer(ServerBehaviourDelegate.REMOVED));
		}
		
		PublishOperation[] tasks = getTasks(kind, moduleList, kindList);
		int size = 2000 + 3500 * moduleList.size() + 500 * tasks.length;
		
		monitor = ProgressUtil.getMonitorFor(monitor);
		monitor.beginTask(NLS.bind(Messages.publishing, getServer().getName()), size);

		MultiStatus tempMulti = new MultiStatus(ServerPlugin.PLUGIN_ID, 0, "", null);

		if (monitor.isCanceled())
			return Status.CANCEL_STATUS;
		
		// start publishing
		Trace.trace(Trace.FINEST, "Calling publishStart()");
		try {
			publishStart(ProgressUtil.getSubMonitorFor(monitor, 1000));
		} catch (CoreException ce) {
			Trace.trace(Trace.INFO, "CoreException publishing to " + toString(), ce);
			return ce.getStatus();
		}
		
		// perform tasks
		MultiStatus taskStatus = performTasks(tasks, monitor);
		if (taskStatus != null)
			tempMulti.addAll(taskStatus);
		
		// publish the server
		try {
			if (!monitor.isCanceled()) {
				publishServer(kind, ProgressUtil.getSubMonitorFor(monitor, 1000));
			}
		} catch (CoreException ce) {
			Trace.trace(Trace.INFO, "CoreException publishing to " + toString(), ce);
			tempMulti.add(ce.getStatus());
		} catch (Exception e) {
			Trace.trace(Trace.SEVERE, "Error publishing configuration to " + toString(), e);
			tempMulti.add(new Status(IStatus.ERROR, ServerPlugin.PLUGIN_ID, 0, Messages.errorPublishing, e));
		}
		
		// publish modules
		if (!monitor.isCanceled()) {
			try {
				publishModules(kind, moduleList, kindList, tempMulti, monitor);
			} catch (Exception e) {
				Trace.trace(Trace.WARNING, "Error while publishing modules", e);
				tempMulti.add(new Status(IStatus.ERROR, ServerPlugin.PLUGIN_ID, 0, Messages.errorPublishing, e));
			}
		}
		
		// end the publishing
		Trace.trace(Trace.FINEST, "Calling publishFinish()");
		try {
			publishFinish(ProgressUtil.getSubMonitorFor(monitor, 500));
		} catch (CoreException ce) {
			Trace.trace(Trace.INFO, "CoreException publishing to " + toString(), ce);
			tempMulti.add(ce.getStatus());
		} catch (Exception e) {
			Trace.trace(Trace.SEVERE, "Error stopping publish to " + toString(), e);
			tempMulti.add(new Status(IStatus.ERROR, ServerPlugin.PLUGIN_ID, 0, Messages.errorPublishing, e));
		}
		
		if (monitor.isCanceled())
			return Status.CANCEL_STATUS;
		
		monitor.done();
		
		Trace.trace(Trace.FINEST, "--<-- Done publishing --<--");
		
		if (tempMulti.getChildren().length == 1)
			return tempMulti.getChildren()[0];
		
		MultiStatus multi = null;
		if (tempMulti.getSeverity() == IStatus.OK)
			multi = new MultiStatus(ServerPlugin.PLUGIN_ID, 0, Messages.publishingStatusOk, null);
		else if (tempMulti.getSeverity() == IStatus.INFO)
			multi = new MultiStatus(ServerPlugin.PLUGIN_ID, 0, Messages.publishingStatusInfo, null);
		else if (tempMulti.getSeverity() == IStatus.WARNING)
			multi = new MultiStatus(ServerPlugin.PLUGIN_ID, 0, Messages.publishingStatusWarning, null);
		else if (tempMulti.getSeverity() == IStatus.ERROR)
			multi = new MultiStatus(ServerPlugin.PLUGIN_ID, 0, Messages.publishingStatusError, null);
		multi.addAll(tempMulti);
		
		return multi;
	}

	/**
	 * Publish a single module.
	 */
	protected IStatus publishModule(int kind, IModule[] module, int deltaKind, IProgressMonitor monitor) {
		Trace.trace(Trace.FINEST, "Publishing module: " + module);
		
		int size = module.length;
		IModule m = module[size - 1];
		monitor.beginTask(NLS.bind(Messages.publishingModule, m.getName()), 1000);
		
		IStatus status = new Status(IStatus.OK, ServerPlugin.PLUGIN_ID, 0, NLS.bind(Messages.publishedModule, m.getName()), null);
		try {
			publishModule(kind, deltaKind, module, monitor);
		} catch (CoreException ce) {
			status = ce.getStatus();
		} catch (Exception e) {
			status = new Status(IStatus.ERROR, ServerPlugin.PLUGIN_ID, 0, Messages.errorPublishing, e);
		}
		
		/*Trace.trace(Trace.FINEST, "Delta:");
		IModuleResourceDelta[] delta = getServerPublishInfo().getDelta(parents, module);
		int size = delta.length;
		for (int i = 0; i < size; i++) {
			((ModuleResourceDelta)delta[i]).trace(">  ");
		}*/
		updatePublishInfo(deltaKind, module);
		
		monitor.done();
		
		Trace.trace(Trace.FINEST, "Done publishing: " + module);
		return status;
	}
	
	protected boolean hasBeenPublished(IModule[] module) {
		return server.getServerPublishInfo().hasModulePublishInfo(module);
	}
	
	protected void addRemovedModules(List moduleList, List kindList) {
		server.getServerPublishInfo().addRemovedModules(moduleList, kindList);
	}
	
	protected void updatePublishInfo(int deltaKind, IModule[] module) {
		if (deltaKind == ServerBehaviourDelegate.REMOVED)
			server.getServerPublishInfo().removeModulePublishInfo(module);
		else
			server.getServerPublishInfo().fill(module);
	}

	/**
	 * Publishes the given modules. Returns true if the publishing
	 * should continue, or false if publishing has failed or is cancelled.
	 * 
	 * Uses 500 ticks plus 3500 ticks per module
	 */
	protected void publishModules(int kind, List modules, List deltaKind, MultiStatus multi, IProgressMonitor monitor) {
		if (modules == null)
			return;
		
		int size = modules.size();
		if (size == 0)
			return;
		
		if (monitor.isCanceled())
			return;
		
		// publish modules
		for (int i = 0; i < size; i++) {
			IStatus status = publishModule(kind, (IModule[]) modules.get(i), ((Integer)deltaKind.get(i)).intValue(), ProgressUtil.getSubMonitorFor(monitor, 3000));
			multi.add(status);
		}
	}

	/**
	 * Returns the publish tasks that have been targetted to this server.
	 * These tasks should be run during publishing.
	 * 
	 * @param kind one of the IServer.PUBLISH_XX constants
	 * @param moduleList a list of modules
	 * @param kindList list of one of the IServer publish change constants
	 * @return a possibly empty array of IOptionalTasks
	 */
	protected final PublishOperation[] getTasks(int kind, List moduleList, List kindList) {
		return server.getTasks(kind, moduleList, kindList);
	}

	/**
	 * Returns all the modules that are on the server, including root
	 * modules and all their children.
	 * 
	 * @return a list of IModule[]s
	 */
	protected final List getAllModules() {
		return server.getAllModules();
	}

	/**
	 * Perform (execute) all the given tasks.
	 * 
	 * @param tasks an array of tasks
	 * @param monitor a progress monitor, or <code>null</code> if progress
	 *    reporting and cancellation are not desired
	 * @return the status
	 */
	protected MultiStatus performTasks(PublishOperation[] tasks, IProgressMonitor monitor) {
		int size = tasks.length;
		Trace.trace(Trace.FINEST, "Performing tasks: " + size);
		
		if (size == 0)
			return null;
		
		MultiStatus multi = new MultiStatus(ServerPlugin.PLUGIN_ID, 0, Messages.taskPerforming, null);
		
		for (int i = 0; i < size; i++) {
			PublishOperation task = tasks[i];
			monitor.subTask(NLS.bind(Messages.taskPerforming, task.toString()));
			try {
				task.execute(ProgressUtil.getSubMonitorFor(monitor, 500), null);
			} catch (CoreException ce) {
				Trace.trace(Trace.SEVERE, "Task failed", ce);
				multi.add(ce.getStatus());
			}
			
			// return early if the monitor has been cancelled
			if (monitor.isCanceled())
				return multi;
		}
		
		return multi;
	}

	/**
	 * Called when resources change within the workspace.
	 * This gives the server an opportunity to update the server or module
	 * restart state.
	 */
	public void handleResourceChange() {
		// do nothing
	}
}