//: GreenhouseControls.java
//////////////////////////////////////////////////
// Copyright (c) Bruce Eckel, 1998
// Source code file from the book "Thinking in Java"
// All rights reserved EXCEPT as allowed by the
// following statements: You can freely use this file
// for your own work (personal or commercial),
// including modifications and distribution in
// executable form only. Permission is granted to use
// this file in classroom situations, including its
// use in presentation materials, as long as the book
// "Thinking in Java" is cited as the source.
// Except in classroom situations, you cannot copy
// and distribute this code; instead, the sole
// distribution point is http://www.BruceEckel.com
// (and official mirror sites) where it is
// freely available. You cannot remove this
// copyright and notice. You cannot distribute
// modified versions of the source code in this
// package. You cannot use this file in printed
// media without the express permission of the
// author. Bruce Eckel makes no representation about
// the suitability of this software for any purpose.
// It is provided "as is" without express or implied
// warranty of any kind, including any implied
// warranty of merchantability, fitness for a
// particular purpose or non-infringement. The entire
// risk as to the quality and performance of the
// software is with you. Bruce Eckel and the
// publisher shall not be liable for any damages
// suffered by you or any third party as a result of
// using or distributing software. In no event will
// Bruce Eckel or the publisher be liable for any
// lost revenue, profit, or data, or for direct,
// indirect, special, consequential, incidental, or
// punitive damages, however caused and regardless of
// the theory of liability, arising out of the use of
// or inability to use software, even if Bruce Eckel
// and the publisher have been advised of the
// possibility of such damages. Should the software
// prove defective, you assume the cost of all
// necessary servicing, repair, or correction. If you
// think you've found an error, please email all
// modified files with clearly commented changes to:
// Bruce@EckelObjects.com. (Please use the same
// address for non-code errors found in the book.)
/////////////////////////////////////////////////
// This produces a specific application of the
// control system, all in a single class. Inner
// classes allow you to encapsulate different
// functionality for each type of event.
package c07.controller;
public class GreenhouseControls
extends Controller {
private boolean light = false;
private boolean water = false;
private String thermostat = "Day";
private class LightOn extends Event {
public LightOn(long eventTime) {
super(eventTime);
}
public void action() {
// Put hardware control code here to
// physically turn on the light.
light = true;
}
public String description() {
return "Light is on";
}
}
private class LightOff extends Event {
public LightOff(long eventTime) {
super(eventTime);
}
public void action() {
// Put hardware control code here to
// physically turn off the light.
light = false;
}
public String description() {
return "Light is off";
}
}
private class WaterOn extends Event {
public WaterOn(long eventTime) {
super(eventTime);
}
public void action() {
// Put hardware control code here
water = true;
}
public String description() {
return "Greenhouse water is on";
}
}
private class WaterOff extends Event {
public WaterOff(long eventTime) {
super(eventTime);
}
public void action() {
// Put hardware control code here
water = false;
}
public String description() {
return "Greenhouse water is off";
}
}
private class ThermostatNight extends Event {
public ThermostatNight(long eventTime) {
super(eventTime);
}
public void action() {
// Put hardware control code here
thermostat = "Night";
}
public String description() {
return "Thermostat on night setting";
}
}
private class ThermostatDay extends Event {
public ThermostatDay(long eventTime) {
super(eventTime);
}
public void action() {
// Put hardware control code here
thermostat = "Day";
}
public String description() {
return "Thermostat on day setting";
}
}
// An example of an action() that inserts a
// new one of itself into the event list:
private int rings;
private class Bell extends Event {
public Bell(long eventTime) {
super(eventTime);
}
public void action() {
// Ring bell every 2 seconds, rings times:
System.out.println("Bing!");
if(--rings > 0)
addEvent(new Bell(
System.currentTimeMillis() + 2000));
}
public String description() {
return "Ring bell";
}
}
private class Restart extends Event {
public Restart(long eventTime) {
super(eventTime);
}
public void action() {
long tm = System.currentTimeMillis();
// Instead of hard-wiring, you could parse
// configuration information from a text
// file here:
rings = 5;
addEvent(new ThermostatNight(tm));
addEvent(new LightOn(tm + 1000));
addEvent(new LightOff(tm + 2000));
addEvent(new WaterOn(tm + 3000));
addEvent(new WaterOff(tm + 8000));
addEvent(new Bell(tm + 9000));
addEvent(new ThermostatDay(tm + 10000));
// Can even add a Restart object!
addEvent(new Restart(tm + 20000));
}
public String description() {
return "Restarting system";
}
}
public static void main(String[] args) {
GreenhouseControls gc =
new GreenhouseControls();
long tm = System.currentTimeMillis();
gc.addEvent(gc.new Restart(tm));
gc.run();
}
} ///:~ |