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
/**
	 * The escape character to use for serialization and deserialization of
	 * parameterized commands.
	 */
	static final char ESCAPE_CHAR = '%';
	/**
	 * The character that separates a parameter id from its value.
	 */
	static final char ID_VALUE_CHAR = '=';
	/**
	 * The character that indicates the end of a list of parameters.
	 */
	static final char PARAMETER_END_CHAR = ')';
	/**
	 * The character that separators parameters from each other.
	 */
	static final char PARAMETER_SEPARATOR_CHAR = ',';
	/**
	 * The character that indicates the start of a list of parameters.
	 */
	static final char PARAMETER_START_CHAR = '(';
	/**
	 * Unescapes special characters in the command id, parameter ids and
	 * parameter values for {@link #deserialize()}. The special characters
	 * {@link #PARAMETER_START_CHAR}, {@link #PARAMETER_END_CHAR},
	 * {@link #ID_VALUE_CHAR}, {@link #PARAMETER_SEPARATOR_CHAR} and
	 * {@link #ESCAPE_CHAR} are escaped by prepending an {@link #ESCAPE_CHAR}
	 * character.
	 * 
	 * @param escapedText