Bug 121709 [Commands] parameters: Add types
I'm going to attach a patch that adds support for typed command parameters. This addresses several issues: - parameter values are strings, but handlers may want to work on objects - multiple handlers of a command should have a consistent way of converting string parameter values to objects - tooling to construct parameterized commands that starts with object parameter values needs a way of producing string parameter values that will work when the command is executed - there should be a way to classify commands by their object parameter types so, given an object, a set of commands that may work with it can be suggested To address these issues, the patch allows parameter types to be declared in the extension-point XML. The example below defines a command for negating integers and a parameter type that works with it. <extension point="org.eclipse.ui.commands"> <command id="org.example.commands.negateInteger" defaultHandler="org.example.commands.NegateIntegerHandler" name="Negate an Integer"> <commandParameter id="param" name="the param" optional="false" typeId="org.example.commands.Integer"/> </command> <commandParameterType id="org.example.commands.Integer" converter="org.example.commands.IntegerConverter" type="java.lang.Integer"/> </extension> In addition to extending the schema for org.eclipse.ui.commands, code has been added to a number of plugins (primarily org.eclipse.core.commands) to support the notion of typed parameters.
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/CommandManager.java
* events from commands controlled by this manager to listeners on this
	 * manager.
	 */
	private IExecutionListener executionListener = null;
	/**
	 * The collection of execution listeners. This collection is
	 * <code>null</code> if there are no listeners.
	 */
	private ListenerList executionListeners = null;
	/**
	 * Adds a listener to this command manager. The listener will be notified
	 * when the set of defined commands changes. This can be used to track the
	 * global appearance and disappearance of commands.
	 * 
	 * @param listener
	 *            The listener to attach; must not be <code>null</code>.
	 */
	public final void addCommandManagerListener(
			final ICommandManagerListener listener) {
		addListenerObject(listener);
	}
	/**
	 * Adds an execution listener to this manager. This listener will be
	 * notified if any of the commands controlled by this manager execute. This
	 * can be used to support macros and instrumentation of commands.
	 * 
	 * @param listener
	 *            The listener to attach; must not be <code>null</code>.
	 */
	public final void addExecutionListener(final IExecutionListener listener) {