Bug 120168 [Field Assist] - should be able to specify character activation subset when auto-activating
ControlContentAdapter (initial release) When there is no triggering keystroke set on a ControlContentAdapter, auto-activation is assumed, and alpha-numerics trigger the auto-activation. It is useful to be able to specify a subset of characters that trigger auto-activation. This is done, for example, by the find/replace dialog RexExProcessor, so that only those characters involving regular expressions will auto-activate the content assist.
bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/ContentProposalAdapter.java
/*
	 * A boolean that indicates whether keystrokes received while the proposal
	 * popup is open should also be propagated to the control.
	 */
	private boolean propagateKeyStroke;
	/*
	 * The listener we install on the control.
	 */
	private Listener controlListener;
	/*
	 * The list of listeners who wish to be notified when something significant
	 * happens with the proposals.
	 */
	private ListenerList proposalListeners = new ListenerList();
	/*
	 * Flag that indicates whether the adapter is enabled. In some cases,
	 * adapters may be installed but depend upon outside state.
	 */
	private boolean isEnabled = true;
	/**
	 * Construct a content proposal adapter that can assist the user with
	 * choosing content for the field.
	 * 
	 * @param control
	 *            the control for which the adapter is providing content assist.
	 * @param controlContentAdapter
	 *            the <code>IControlContentAdapter</code> used to obtain and
	 *            update the control's contents as proposals are accepted.
	 * @param proposalProvider
	 *            the <code>IContentProposalProvider</code> used to obtain