annotate src/samer/maths/VGenerator.java @ 8:5e3cbbf173aa tip

Reorganise some more

/*
 *	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.maths;
import	samer.core.*;
import	samer.core.types.*;
import	samer.core.util.*;
import	java.awt.*;
import	java.util.*;

/**
	A Viewable random number generator.
	The Generator itself must expose any parameters
	it has, but this object allows the user to
	control what class of generator to use. 
  */

public class VGenerator extends Viewable implements Agent, Generator
{
	Generator	gen;
	String		desc;		// description of the current generator

	public VGenerator(String nm) throws Exception { this(nm,new Zero()); }
	public VGenerator(String nm, Generator g) throws Exception {
		super(nm); setAgent(this);	gen = g;
		Shell.registerViewable(this);
	}
	
	public double next() { return gen.next(); }
	public void   next(double[] x) { gen.next(x); }

	public void dispose() 
	{
		Shell.deregisterViewable(this);
		gen.dispose();
		super.dispose();
	}

	public Generator getGenerator() { return gen; }
	public void setGenerator(Generator g) {
		gen.dispose(); gen=g; changed();
	}

	public Viewer getViewer() { return new UI(); }

	private class UI extends BaseViewer {
		UI() {
			super(VGenerator.this);
			update(VGenerator.this,null);
		}

		public void update(Observable o, Object arg) {
			super.update(o,arg);
			Shell.trace("VGenerator update to "+gen.toString());
			setText(getLabel()+": "+gen.toString());
		}
	}

	public void getCommands(Registry r)	{ r.add("set").add("next"); }	

	public void execute(String cmd, Environment env) throws Exception
	{
		if (cmd.equals("set")) {
			Shell.push(getNode());
			setGenerator((Generator)X.object(env.datum()));
			Shell.pop();
		} else if (cmd.equals("next")) {
			env.add(new Double(gen.next()));
		}
	}
}