Bug 78666 [KeyBindings] errors: No warning if keybinding definitions collide
Using 3.1 M3, if I define a keybinding in the default "windows" context and with keybinding of "CTRL+B" or "CTRL+U", the keybindings are silently removed. In the very least, the conflict should be logged. Ideally, the user would also see the collision in the keybindings preference page. In this case, I think it's better to show some information than to just kill these mapping and not explain why. Eclipse is a dynamic platform. There are lots of scenarios where keybindings get added into a configuration and start conflicting with previously working keybindings.
bundles/org.eclipse.jface/src/org/eclipse/jface/bindings/BindingManager.java
private static final String[] expand(String string, final String separator) {
		
		if (string == null || separator == null) {
			return new String[0];
		}
		final List strings = new ArrayList();
		final StringBuffer stringBuffer = new StringBuffer();
		string = string.trim(); 
		if (string.length() > 0) {
			final StringTokenizer stringTokenizer = new StringTokenizer(string,
					separator);
			while (stringTokenizer.hasMoreElements()) {
				if (stringBuffer.length() > 0) {
					stringBuffer.append(separator);
				}
				stringBuffer.append(((String) stringTokenizer.nextElement())
						.trim());
				strings.add(stringBuffer.toString());
			}
		}
		Collections.reverse(strings);
		strings.add(Util.ZERO_LENGTH_STRING);
		strings.add(null);
		return (String[]) strings.toArray(new String[strings.size()]);
	}
	/**
	 * The active bindings. This is a map of triggers (
	 * <code>TriggerSequence</code>) to bindings (<code>Binding</code>).
	 * This value will only be <code>null</code> if the active bindings have
	 * not yet been computed. Otherwise, this value may be empty.