Bug 136763 Performance improvements to BindingManager
Build id: I20060413-0010 One of our performance tests that still shows significant regression is opening editors. With profiling I found that 0.8% of that time is in Collections.unmodifiableMap(...) called by three methods in BindingManager. Another 0.15% is from instantiating new TrigerSequence[0] in three locations in BindingManager. In the first case, the creation of an immutable map is completely unnecessary - the methods are private, the maps are never exposed across API boundaries, and there is never any risk that the maps will be modified. The creation of empty TriggerSequence arrays can also be avoided with a singleton. I will attach a patch that collectively saves about 1% of the total editor startup time (elapsed time as measured by sampling profiler). These are very simple and safe fixes that I recommend considering for RC2.
bundles/org.eclipse.jface/src/org/eclipse/jface/bindings/BindingManager.java
*/
			final String bestLocale = bestBinding.getLocale();
			final String currentLocale = currentBinding.getLocale();
			if ((bestLocale == null) && (currentLocale != null)) {
				bestBinding = currentBinding;
			}
			if (!(Util.equals(bestLocale, currentLocale))) {
				continue;
			}
			/*
			 * Bindings with a platform are given preference over those that do
			 * not.
			 */
			final String bestPlatform = bestBinding.getPlatform();
			final String currentPlatform = currentBinding.getPlatform();
			if ((bestPlatform == null) && (currentPlatform != null)) {
				bestBinding = currentBinding;
			}
			if (!(Util.equals(bestPlatform, currentPlatform))) {
				continue;
			}
			/*
			 * Check to see which has the least number of triggers in the
			 * trigger sequence.
			 */
			final TriggerSequence bestTriggerSequence = bestBinding
					.getTriggerSequence();
			final TriggerSequence currentTriggerSequence = currentBinding
					.getTriggerSequence();
			final Trigger[] bestTriggers = bestTriggerSequence.getTriggers();