bindingmanager.java

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			return true; // shortcut a common case
		}

		for (int i = 0; i < locales.length; i++) {
			if (Util.equals(locales[i], locale)) {
				matches = true;
				break;
			}
		}

		return matches;
	}

	/**
	 * <p>
	 * Tests whether the platform for the binding matches one of the active
	 * platforms.
	 * </p>
	 * <p>
	 * This method completes in <code>O(n)</code>, where <code>n</code> is
	 * the number of active platforms.
	 * </p>
	 * 
	 * @param binding
	 *            The binding with which to test; must not be <code>null</code>.
	 * @return <code>true</code> if the binding's platform matches;
	 *         <code>false</code> otherwise.
	 */
	private final boolean platformMatches(final Binding binding) {
		boolean matches = false;

		final String platform = binding.getPlatform();
		if (platform == null) {
			return true; // shortcut a common case
		}

		for (int i = 0; i < platforms.length; i++) {
			if (Util.equals(platforms[i], platform)) {
				matches = true;
				break;
			}
		}

		return matches;
	}

	/**
	 * <p>
	 * This recomputes the bindings based on changes to the state of the world.
	 * This computation can be triggered by changes to contexts, the active
	 * scheme, the locale, or the platform. This method tries to use the cache
	 * of pre-computed bindings, if possible. When this method completes,
	 * <code>activeBindings</code> will be set to the current set of bindings
	 * and <code>cachedBindings</code> will contain an instance of
	 * <code>CachedBindingSet</code> representing these bindings.
	 * </p>
	 * <p>
	 * This method completes in <code>O(n+pn)</code>, where <code>n</code>
	 * is the number of bindings, and <code>p</code> is the average number of
	 * triggers in a trigger sequence.
	 * </p>
	 */
	private final void recomputeBindings() {
		if (bindings == null) {
			// Not yet initialized. This is happening too early. Do nothing.
			setActiveBindings(Collections.EMPTY_MAP, Collections.EMPTY_MAP,
					Collections.EMPTY_MAP);
			return;
		}

		// Figure out the current state.
		final Set activeContextIds = new HashSet(contextManager
				.getActiveContextIds());
		final Map activeContextTree = createFilteredContextTreeFor(activeContextIds);

		// Build a cached binding set for that state.
		final CachedBindingSet bindingCache = new CachedBindingSet(
				activeContextTree, locales, platforms, activeSchemeIds);

		/*
		 * Check if the cached binding set already exists. If so, simply set the
		 * active bindings and return.
		 */
		CachedBindingSet existingCache = (CachedBindingSet) cachedBindings
				.get(bindingCache);
		if (existingCache == null) {
			existingCache = bindingCache;
			cachedBindings.put(existingCache, existingCache);
		}
		Map commandIdsByTrigger = existingCache.getBindingsByTrigger();
		if (commandIdsByTrigger != null) {
			if (DEBUG) {
				Tracing.printTrace("BINDINGS", "Cache hit"); //$NON-NLS-1$ //$NON-NLS-2$
			}
			setActiveBindings(commandIdsByTrigger, existingCache
					.getTriggersByCommandId(), existingCache.getPrefixTable());
			return;
		}

		// There is no cached entry for this.
		if (DEBUG) {
			Tracing.printTrace("BINDINGS", "Cache miss"); //$NON-NLS-1$ //$NON-NLS-2$
		}

		// Compute the active bindings.
		commandIdsByTrigger = new HashMap();
		final Map triggersByParameterizedCommand = new HashMap();
		computeBindings(activeContextTree, commandIdsByTrigger,
				triggersByParameterizedCommand);
		existingCache.setBindingsByTrigger(commandIdsByTrigger);
		existingCache.setTriggersByCommandId(triggersByParameterizedCommand);
		setActiveBindings(commandIdsByTrigger, triggersByParameterizedCommand,
				buildPrefixTable(commandIdsByTrigger));
		existingCache.setPrefixTable(prefixTable);
	}

	/**
	 * <p>Remove the specific binding by identity. Does nothing if the binding is
	 * not in the manager.</p>
	 * <p>
	 * This method completes in <code>O(n)</code>, where <code>n</code> is
	 * the number of bindings.
	 * </p>
	 * 
	 * @param binding
	 *            The binding to be removed; must not be <code>null</code>.
	 * @since 3.2
	 */
	public final void removeBinding(final Binding binding) {
		if (bindings == null || bindings.length < 1) {
			return;
		}

		final Binding[] newBindings = new Binding[bindings.length];
		boolean bindingsChanged = false;
		int index = 0;
		for (int i = 0; i < bindingCount; i++) {
			final Binding b = bindings[i];
			if (b == binding) {
				bindingsChanged = true;
			} else {
				newBindings[index++] = b;
			}
		}

		if (bindingsChanged) {
			this.bindings = newBindings;
			bindingCount = index;
			clearCache();
		}
	}

	/**
	 * <p>
	 * Removes a listener from this binding manager.
	 * </p>
	 * <p>
	 * This method completes in amortized <code>O(1)</code>.
	 * </p>
	 * 
	 * @param listener
	 *            The listener to be removed; must not be <code>null</code>.
	 */
	public final void removeBindingManagerListener(
			final IBindingManagerListener listener) {
		removeListenerObject(listener);
	}

	/**
	 * <p>
	 * Removes any binding that matches the given values -- regardless of
	 * command identifier.
	 * </p>
	 * <p>
	 * This method completes in <code>O(n)</code>, where <code>n</code> is
	 * the number of bindings.
	 * </p>
	 * 
	 * @param sequence
	 *            The sequence to match; may be <code>null</code>.
	 * @param schemeId
	 *            The scheme id to match; may be <code>null</code>.
	 * @param contextId
	 *            The context id to match; may be <code>null</code>.
	 * @param locale
	 *            The locale to match; may be <code>null</code>.
	 * @param platform
	 *            The platform to match; may be <code>null</code>.
	 * @param windowManager
	 *            The window manager to match; may be <code>null</code>. TODO
	 *            Currently ignored.
	 * @param type
	 *            The type to look for.
	 * 
	 */
	public final void removeBindings(final TriggerSequence sequence,
			final String schemeId, final String contextId, final String locale,
			final String platform, final String windowManager, final int type) {
		if ((bindings == null) || (bindingCount < 1)) {
			return;
		}

		final Binding[] newBindings = new Binding[bindings.length];
		boolean bindingsChanged = false;
		int index = 0;
		for (int i = 0; i < bindingCount; i++) {
			final Binding binding = bindings[i];
			boolean equals = true;
			equals &= Util.equals(sequence, binding.getTriggerSequence());
			equals &= Util.equals(schemeId, binding.getSchemeId());
			equals &= Util.equals(contextId, binding.getContextId());
			equals &= Util.equals(locale, binding.getLocale());
			equals &= Util.equals(platform, binding.getPlatform());
			equals &= (type == binding.getType());
			if (equals) {
				bindingsChanged = true;
			} else {
				newBindings[index++] = binding;
			}
		}

		if (bindingsChanged) {
			this.bindings = newBindings;
			bindingCount = index;
			clearCache();
		}
	}

	/**
	 * <p>
	 * Attempts to remove deletion markers from the collection of bindings.
	 * </p>
	 * <p>
	 * This method completes in <code>O(n)</code>, where <code>n</code> is
	 * the number of bindings.
	 * </p>
	 * 
	 * @param bindings
	 *            The bindings from which the deleted items should be removed.
	 *            This array should not be <code>null</code>, but may be
	 *            empty.
	 * @return The array of bindings with the deletions removed; never
	 *         <code>null</code>, but may be empty. Contains only instances
	 *         of <code>Binding</code>.
	 */
	private final Binding[] removeDeletions(final Binding[] bindings) {
		final Map deletions = new HashMap();
		final Binding[] bindingsCopy = new Binding[bindingCount];
		System.arraycopy(bindings, 0, bindingsCopy, 0, bindingCount);
		int deletedCount = 0;

		// Extract the deletions.
		for (int i = 0; i < bindingCount; i++) {
			final Binding binding = bindingsCopy[i];
			if ((binding.getParameterizedCommand() == null)
					&& (localeMatches(binding)) && (platformMatches(binding))) {
				final TriggerSequence sequence = binding.getTriggerSequence();
				final Object currentValue = deletions.get(sequence);
				if (currentValue instanceof Binding) {
					final Collection collection = new ArrayList(2);
					collection.add(currentValue);
					collection.add(binding);
					deletions.put(sequence, collection);
				} else if (currentValue instanceof Collection) {
					final Collection collection = (Collection) currentValue;
					collection.add(binding);
				} else {
					deletions.put(sequence, binding);
				}
				bindingsCopy[i] = null;
				deletedCount++;
			}
		}

		if (DEBUG) {
			Tracing.printTrace("BINDINGS", "There are " + deletions.size() //$NON-NLS-1$ //$NON-NLS-2$
					+ " deletion markers"); //$NON-NLS-1$
		}

		// Remove the deleted items.
		for (int i = 0; i < bindingCount; i++) {
			final Binding binding = bindingsCopy[i];
			if (binding != null) {
				final Object deletion = deletions.get(binding
						.getTriggerSequence());
				if (deletion instanceof Binding) {
					if (((Binding) deletion).deletes(binding)) {
						bindingsCopy[i] = null;
						deletedCount++;
					}

				} else if (deletion instanceof Collection) {
					final Collection collection = (Collection) deletion;
					final Iterator iterator = collection.iterator();
					while (iterator.hasNext()) {
						final Object deletionBinding = iterator.next();
						if (deletionBinding instanceof Binding) {
							if (((Binding) deletionBinding).deletes(binding)) {
								bindingsCopy[i] = null;
								deletedCount++;
								break;
							}
						}
					}

				}
			}
		}

		// Compact the array.
		final Binding[] returnValue = new Binding[bindingCount - deletedCount];
		int index = 0;
		for (int i = 0; i < bindingCount; i++) {
			final Binding binding = bindingsCopy[i];
			if (binding != null) {
				returnValue[index++] = binding;
			}
		}

		return returnValue;
	}

	/**
	 * <p>
	 * Attempts to resolve the conflicts for the given bindings -- irrespective
	 * of the currently active contexts. This means that type and scheme will be
	 * considered.
	 * </p>
	 * <p>
	 * This method completes in <code>O(n)</code>, where <code>n</code> is
	 * the number of bindings.
	 * </p>
	 * 
	 * @param bindings
	 *            The bindings which all match the same trigger sequence; must
	 *            not be <code>null</code>, and should contain at least two
	 *            items. This collection should only contain instances of
	 *            <code>Binding</code> (i.e., no <code>null</code> values).
	 * @return The collection of bindings which match the current scheme.
	 */
	private final Collection resolveConflicts(final Collection bindings) {
		final Collection matches = new ArrayList();
		final Iterator bindingItr = bindings.iterator();
		Binding bestMatch = (Binding) bindingItr.next();
		matches.add(bestMatch);

		/*
		 * Iterate over each binding and compares it with the best match. If a
		 * better match is found, then replace the best match and clear the
		 * collection. If the current binding is equivalent, then simply add it
		 * to the collection of matches. If the current binding is worse, then
		 * do nothing.
		 */
		while (bindingItr.hasNext()) {
			final Binding current = (Binding) bindingItr.next();

			/*
			 * SCHEME: Test whether the current is in a child scheme. Bindings
			 * defined in a child scheme will take priority over bindings
			 * defined in a parent scheme -- assuming that consulting their
			 * contexts led to a conflict.
			 */
			final String currentSchemeId = current.getSchemeId();
			final String bestSchemeId = bestMatch.getSchemeId();
			final int compareTo = compareSchemes(bestSchemeId, currentSchemeId);
			if (compareTo > 0) {
				bestMatch = current;
				matches.clear();
				matches.add(current);
			}
			if (compareTo != 0) {
				continue;
			}

			/*
			 * TYPE: Test for type superiority.
			 */
			if (current.getType() > bestMatch.getType()) {
				bestMatch = current;
				matches.clear();
				matches.add(current);
				continue;
			} else if (bestMatch.getType() > current.getType()) {
				continue;
			}

			// The bindings are equivalent.
			matches.add(current);
		}

		// Return all of the matches.
		return matches;
	}

	/**
	 * <p>
	 * Attempts to resolve the conflicts for the g