comparison src/samer/core_/Agent.java @ 0:bf79fb79ee13

Initial Mercurial check in.

+/*
+ *	Agent.java	
+ *
+ *	Copyright (c) 2000, Samer Abdallah, King's College London.
+ *	All rights reserved.
+ *
+ *	This software is provided AS iS and WITHOUT ANY WARRANTY; 
+ *	without even the implied warranty of MERCHANTABILITY or 
+ *	FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+package samer.core;
+
+/**
+	An Agent is something that can handle commands.
+	It can also optionally report which commands it
+	can handle so that they can be exposed in some
+	way, eg buttons or a menu.
+ */
+
+public interface Agent
+{
+	/**
+		Bad interface name, I know, but a Registry is
+		supplied to an agent so that it can report
+		which commands it handles. The implementation
+		of the Registry can do whatever it likes with
+		the names: compile a list, create buttons or a
+		menu, or just ignore them.
+
+		<p>May eventually want to be able to supply
+		more information abdut a command, so that we
+		can, eg, put an icon on a toolbar or have a
+		tool tip
+	 */
+
+	public interface Registry {
+		Registry add( String name);
+
+		/**
+			The second form of add, with a boolean
+			second argument suggests that the command expects
+			a boolean argument and can thus be associated
+			with a checkbox or check menu item.
+		 */
+
+		Registry add( String name, boolean initialValue);
+
+		/** 
+			This means that the following commands reported
+			to add() are to be directed to a different Agent
+		 */
+
+		void     setTarget(Agent a);
+
+		/** this means start a new group */
+		void group(); 
+	}
+
+	/** Implementations can use the Registry to report which
+		commands they respond to */
+	void getCommands(Registry r);
+
+	/** This must do what the named command says using the given Environment
+		for parameters or supplimentary data. */
+	void execute( String name, Environment env) throws Exception;
+}