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
parameterId = unescape(idEqualsValue);
				parameterValue = null;
			} else {
				parameterId = unescape(idEqualsValue.substring(0,
						equalsPosition));
				parameterValue = unescape(idEqualsValue
						.substring(equalsPosition + 1));
			}
			for (int i = 0; i < parameters.length; i++) {
				final IParameter parameter = parameters[i];
				if (parameter.getId().equals(parameterId)) {
					paramList.add(new Parameterization(parameter,
							parameterValue));
					break;
				}
			}
		} while (commaPosition != -1);
		return (Parameterization[]) paramList
				.toArray(new Parameterization[paramList.size()]);
	}
	/**
	 * Removes a listener from this command manager.
	 * 
	 * @param listener
	 *            The listener to be removed; must not be <code>null</code>.
	 */
	public final void removeCommandManagerListener(
			final ICommandManagerListener listener) {
		removeListenerObject(listener);