//: c08:GreenhouseControls.java // From 'Thinking in Java, 2nd ed.' by Bruce Eckel // www.BruceEckel.com. See copyright notice in CopyRight.txt. // 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. import c08.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 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(); } } ///:~